build/Makefile

 CXX = g++
-INCLUDE = -I/Users/pascal/framebuffer_testing/include/ -I/Users/pascal/framebuffer_testing/include/ -I/usr/local/opt/freetype/include/ -I/usr/local/opt/freetype/include/freetype2/
+INCLUDE = -I/Users/pascal/framebuffer_testing/include/ -I/Users/pascal/framebuffer_testing/include/ -I/usr/local/opt/freetype/include/ -I/usr/local/opt/freetype/include/freetype2/ -I/Users/pascal/framebuffer_testing/include/imgui/
+INCLUDE += -I/Users/pascal/framebuffer_testing/include/SDL2/
 SRC = /Users/pascal/framebuffer_testing/src/
+IMGUISRC = /Users/pascal/framebuffer_testing/src/imgui/
 LIB = -L/Users/pascal/framebuffer_testing/lib -L/usr/local/opt/freetype/lib/ -lSDL2-2.0.0 -lfreetype
 
 FRW = -framework OpenGl
-OPT = -mtune=native -march=native -O3 -finline-functions -funroll-loops -ftree-vectorize -std=c++11
+OPT = -mtune=native -march=native -O3 -finline-functions -funroll-loops -ftree-vectorize -std=c++11 -Wall -Wpedantic
+COMPAT = -mmacosx-version-min=10.13
 
 SOURCES = ${SRC}main.cpp ${SRC}glad.c ${SRC}init.cpp ${SRC}shader.cpp
-OBJS = main.o glad.o init.o shader.o
+IMGUISOURCES = ${IMGUISRC}imgui_draw.cpp ${IMGUISRC}imgui_impl_opengl3.cpp ${IMGUISRC}imgui_impl_sdl.cpp ${IMGUISRC}imgui_widgets.cpp ${IMGUISRC}imgui.cpp
+OBJS = main.o glad.o init.o shader.o imgui_draw.o imgui_impl_opengl3.o imgui_impl_sdl.o imgui_widgets.o imgui.o
 
 .PHONY: game
 game:
 	${CXX} -c ${INCLUDE} ${SOURCES} -std=c++11 ${OPT}
+	${CXX} -c ${INCLUDE} ${IMGUISOURCES} -std=c++11 ${OPT}
 	${CXX} ${LIB} ${FRW} ${INCLUDE} ${OBJS} -o program -std=c++11 -v ${OPT}
 	rm *.o
+
+.PHONY: acheron
+acheron:
+		${CXX} -c ${INCLUDE} ${SOURCES} -std=c++11 ${OPT} ${COMPAT}
+		${CXX} -c ${INCLUDE} ${IMGUISOURCES} -std=c++11 ${OPT} ${COMPAT}
+		${CXX} ${LIB} ${FRW} ${INCLUDE} ${OBJS} -o program -std=c++11 -v ${OPT} ${COMPAT}
+		rm *.o

build/imgui.ini

+[Window][Debug##Default]
+Pos=60,60
+Size=400,400
+Collapsed=0
+
+[Window][Hello World]
+Pos=1298,88
+Size=149,48
+Collapsed=0
+
+[Window][Controller]
+Pos=1296,1
+Size=340,345
+Collapsed=0
+

include/imgui/imconfig.h

+//-----------------------------------------------------------------------------
+// COMPILE-TIME OPTIONS FOR DEAR IMGUI
+// Runtime options (clipboard callbacks, enabling various features, etc.) can generally be set via the ImGuiIO structure.
+// You can use ImGui::SetAllocatorFunctions() before calling ImGui::CreateContext() to rewire memory allocation functions.
+//-----------------------------------------------------------------------------
+// A) You may edit imconfig.h (and not overwrite it when updating Dear ImGui, or maintain a patch/branch with your modifications to imconfig.h)
+// B) or add configuration directives in your own file and compile with #define IMGUI_USER_CONFIG "myfilename.h"
+// If you do so you need to make sure that configuration settings are defined consistently _everywhere_ Dear ImGui is used, which include
+// the imgui*.cpp files but also _any_ of your code that uses Dear ImGui. This is because some compile-time options have an affect on data structures.
+// Defining those options in imconfig.h will ensure every compilation unit gets to see the same data structure layouts.
+// Call IMGUI_CHECKVERSION() from your .cpp files to verify that the data structures your files are using are matching the ones imgui.cpp is using.
+//-----------------------------------------------------------------------------
+
+#pragma once
+
+//---- Define assertion handler. Defaults to calling assert().
+// If your macro uses multiple statements, make sure is enclosed in a 'do { .. } while (0)' block so it can be used as a single statement.
+//#define IM_ASSERT(_EXPR)  MyAssert(_EXPR)
+//#define IM_ASSERT(_EXPR)  ((void)(_EXPR))     // Disable asserts
+
+//---- Define attributes of all API symbols declarations, e.g. for DLL under Windows
+// Using dear imgui via a shared library is not recommended, because of function call overhead and because we don't guarantee backward nor forward ABI compatibility.
+//#define IMGUI_API __declspec( dllexport )
+//#define IMGUI_API __declspec( dllimport )
+
+//---- Don't define obsolete functions/enums/behaviors. Consider enabling from time to time after updating to avoid using soon-to-be obsolete function/names.
+//#define IMGUI_DISABLE_OBSOLETE_FUNCTIONS
+
+//---- Disable all of Dear ImGui or don't implement standard windows.
+// It is very strongly recommended to NOT disable the demo windows during development. Please read comments in imgui_demo.cpp.
+//#define IMGUI_DISABLE                                     // Disable everything: all headers and source files will be empty.
+//#define IMGUI_DISABLE_DEMO_WINDOWS                        // Disable demo windows: ShowDemoWindow()/ShowStyleEditor() will be empty. Not recommended.
+//#define IMGUI_DISABLE_METRICS_WINDOW                      // Disable debug/metrics window: ShowMetricsWindow() will be empty.
+
+//---- Don't implement some functions to reduce linkage requirements.
+//#define IMGUI_DISABLE_WIN32_DEFAULT_CLIPBOARD_FUNCTIONS   // [Win32] Don't implement default clipboard handler. Won't use and link with OpenClipboard/GetClipboardData/CloseClipboard etc.
+//#define IMGUI_DISABLE_WIN32_DEFAULT_IME_FUNCTIONS         // [Win32] Don't implement default IME handler. Won't use and link with ImmGetContext/ImmSetCompositionWindow.
+//#define IMGUI_DISABLE_WIN32_FUNCTIONS                     // [Win32] Won't use and link with any Win32 function (clipboard, ime).
+//#define IMGUI_ENABLE_OSX_DEFAULT_CLIPBOARD_FUNCTIONS      // [OSX] Implement default OSX clipboard handler (need to link with '-framework ApplicationServices', this is why this is not the default).
+//#define IMGUI_DISABLE_DEFAULT_FORMAT_FUNCTIONS            // Don't implement ImFormatString/ImFormatStringV so you can implement them yourself (e.g. if you don't want to link with vsnprintf)
+//#define IMGUI_DISABLE_DEFAULT_MATH_FUNCTIONS              // Don't implement ImFabs/ImSqrt/ImPow/ImFmod/ImCos/ImSin/ImAcos/ImAtan2 so you can implement them yourself.
+//#define IMGUI_DISABLE_DEFAULT_FILE_FUNCTIONS              // Don't implement ImFileOpen/ImFileClose/ImFileRead/ImFileWrite so you can implement them yourself if you don't want to link with fopen/fclose/fread/fwrite. This will also disable the LogToTTY() function.
+//#define IMGUI_DISABLE_DEFAULT_ALLOCATORS                  // Don't implement default allocators calling malloc()/free() to avoid linking with them. You will need to call ImGui::SetAllocatorFunctions().
+
+//---- Include imgui_user.h at the end of imgui.h as a convenience
+//#define IMGUI_INCLUDE_IMGUI_USER_H
+
+//---- Pack colors to BGRA8 instead of RGBA8 (to avoid converting from one to another)
+//#define IMGUI_USE_BGRA_PACKED_COLOR
+
+//---- Use 32-bit for ImWchar (default is 16-bit) to support full unicode code points.
+//#define IMGUI_USE_WCHAR32
+
+//---- Avoid multiple STB libraries implementations, or redefine path/filenames to prioritize another version
+// By default the embedded implementations are declared static and not available outside of imgui cpp files.
+//#define IMGUI_STB_TRUETYPE_FILENAME   "my_folder/stb_truetype.h"
+//#define IMGUI_STB_RECT_PACK_FILENAME  "my_folder/stb_rect_pack.h"
+//#define IMGUI_DISABLE_STB_TRUETYPE_IMPLEMENTATION
+//#define IMGUI_DISABLE_STB_RECT_PACK_IMPLEMENTATION
+
+//---- Unless IMGUI_DISABLE_DEFAULT_FORMAT_FUNCTIONS is defined, use the much faster STB sprintf library implementation of vsnprintf instead of the one from the default C library.
+// Note that stb_sprintf.h is meant to be provided by the user and available in the include path at compile time. Also, the compatibility checks of the arguments and formats done by clang and GCC will be disabled in order to support the extra formats provided by STB sprintf.
+// #define IMGUI_USE_STB_SPRINTF
+
+//---- Define constructor and implicit cast operators to convert back<>forth between your math types and ImVec2/ImVec4.
+// This will be inlined as part of ImVec2 and ImVec4 class declarations.
+/*
+#define IM_VEC2_CLASS_EXTRA                                                 \
+        ImVec2(const MyVec2& f) { x = f.x; y = f.y; }                       \
+        operator MyVec2() const { return MyVec2(x,y); }
+
+#define IM_VEC4_CLASS_EXTRA                                                 \
+        ImVec4(const MyVec4& f) { x = f.x; y = f.y; z = f.z; w = f.w; }     \
+        operator MyVec4() const { return MyVec4(x,y,z,w); }
+*/
+
+//---- Use 32-bit vertex indices (default is 16-bit) is one way to allow large meshes with more than 64K vertices.
+// Your renderer back-end will need to support it (most example renderer back-ends support both 16/32-bit indices).
+// Another way to allow large meshes while keeping 16-bit indices is to handle ImDrawCmd::VtxOffset in your renderer.
+// Read about ImGuiBackendFlags_RendererHasVtxOffset for details.
+//#define ImDrawIdx unsigned int
+
+//---- Override ImDrawCallback signature (will need to modify renderer back-ends accordingly)
+//struct ImDrawList;
+//struct ImDrawCmd;
+//typedef void (*MyImDrawCallback)(const ImDrawList* draw_list, const ImDrawCmd* cmd, void* my_renderer_user_data);
+//#define ImDrawCallback MyImDrawCallback
+
+//---- Debug Tools: Macro to break in Debugger
+// (use 'Metrics->Tools->Item Picker' to pick widgets with the mouse and break into them for easy debugging.)
+//#define IM_DEBUG_BREAK  IM_ASSERT(0)
+//#define IM_DEBUG_BREAK  __debugbreak()
+
+//---- Debug Tools: Have the Item Picker break in the ItemAdd() function instead of ItemHoverable(),
+// (which comes earlier in the code, will catch a few extra items, allow picking items other than Hovered one.)
+// This adds a small runtime cost which is why it is not enabled by default.
+//#define IMGUI_DEBUG_TOOL_ITEM_PICKER_EX
+
+//---- Debug Tools: Enable slower asserts
+//#define IMGUI_DEBUG_PARANOID
+
+//---- Tip: You can add extra functions within the ImGui:: namespace, here or in your own headers files.
+/*
+namespace ImGui
+{
+    void MyFunction(const char* name, const MyMatrix44& v);
+}
+*/

include/imgui/imgui_impl_opengl3.h

+// dear imgui: Renderer for modern OpenGL with shaders / programmatic pipeline
+// - Desktop GL: 2.x 3.x 4.x
+// - Embedded GL: ES 2.0 (WebGL 1.0), ES 3.0 (WebGL 2.0)
+// This needs to be used along with a Platform Binding (e.g. GLFW, SDL, Win32, custom..)
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID!
+//  [x] Renderer: Desktop GL only: Support for large meshes (64k+ vertices) with 16-bit indices.
+
+// You can copy and use unmodified imgui_impl_* files in your project. See main.cpp for an example of using this.
+// If you are new to dear imgui, read examples/README.txt and read the documentation at the top of imgui.cpp.
+// https://github.com/ocornut/imgui
+
+// About Desktop OpenGL function loaders:
+//  Modern desktop OpenGL doesn't have a standard portable header file to load OpenGL function pointers.
+//  Helper libraries are often used for this purpose! Here we are supporting a few common ones (gl3w, glew, glad).
+//  You may use another loader/header of your choice (glext, glLoadGen, etc.), or chose to manually implement your own.
+
+// About GLSL version:
+//  The 'glsl_version' initialization parameter should be NULL (default) or a "#version XXX" string.
+//  On computer platform the GLSL version default to "#version 130". On OpenGL ES 3 platform it defaults to "#version 300 es"
+//  Only override if your GL version doesn't handle this GLSL version. See GLSL version table at the top of imgui_impl_opengl3.cpp.
+
+#pragma once
+#include "imgui.h"      // IMGUI_IMPL_API
+
+// Backend API
+IMGUI_IMPL_API bool     ImGui_ImplOpenGL3_Init(const char* glsl_version = NULL);
+IMGUI_IMPL_API void     ImGui_ImplOpenGL3_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplOpenGL3_NewFrame();
+IMGUI_IMPL_API void     ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data);
+
+// (Optional) Called by Init/NewFrame/Shutdown
+IMGUI_IMPL_API bool     ImGui_ImplOpenGL3_CreateFontsTexture();
+IMGUI_IMPL_API void     ImGui_ImplOpenGL3_DestroyFontsTexture();
+IMGUI_IMPL_API bool     ImGui_ImplOpenGL3_CreateDeviceObjects();
+IMGUI_IMPL_API void     ImGui_ImplOpenGL3_DestroyDeviceObjects();
+
+// Specific OpenGL versions
+//#define IMGUI_IMPL_OPENGL_ES2     // Auto-detected on Emscripten
+//#define IMGUI_IMPL_OPENGL_ES3     // Auto-detected on iOS/Android
+
+// Desktop OpenGL: attempt to detect default GL loader based on available header files.
+// If auto-detection fails or doesn't select the same GL loader file as used by your application,
+// you are likely to get a crash in ImGui_ImplOpenGL3_Init().
+// You can explicitly select a loader by using '#define IMGUI_IMPL_OPENGL_LOADER_XXX' in imconfig.h or compiler command-line.
+#if !defined(IMGUI_IMPL_OPENGL_LOADER_GL3W) \
+ && !defined(IMGUI_IMPL_OPENGL_LOADER_GLEW) \
+ && !defined(IMGUI_IMPL_OPENGL_LOADER_GLAD) \
+ && !defined(IMGUI_IMPL_OPENGL_LOADER_GLBINDING2) \
+ && !defined(IMGUI_IMPL_OPENGL_LOADER_GLBINDING3) \
+ && !defined(IMGUI_IMPL_OPENGL_LOADER_CUSTOM)
+    #if defined(__has_include)
+        #if __has_include(<GL/glew.h>)
+            #define IMGUI_IMPL_OPENGL_LOADER_GLEW
+        #elif __has_include(<glad/glad.h>)
+            #define IMGUI_IMPL_OPENGL_LOADER_GLAD
+        #elif __has_include(<GL/gl3w.h>)
+            #define IMGUI_IMPL_OPENGL_LOADER_GL3W
+        #elif __has_include(<glbinding/glbinding.h>)
+            #define IMGUI_IMPL_OPENGL_LOADER_GLBINDING3
+        #elif __has_include(<glbinding/Binding.h>)
+            #define IMGUI_IMPL_OPENGL_LOADER_GLBINDING2
+        #else
+            #error "Cannot detect OpenGL loader!"
+        #endif
+    #else
+        #define IMGUI_IMPL_OPENGL_LOADER_GL3W       // Default to GL3W
+    #endif
+#endif
+

include/imgui/imgui_impl_sdl.h

+// dear imgui: Platform Binding for SDL2
+// This needs to be used along with a Renderer (e.g. DirectX11, OpenGL3, Vulkan..)
+// (Info: SDL2 is a cross-platform general purpose library for handling windows, inputs, graphics context creation, etc.)
+
+// Implemented features:
+//  [X] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'.
+//  [X] Platform: Clipboard support.
+//  [X] Platform: Keyboard arrays indexed using SDL_SCANCODE_* codes, e.g. ImGui::IsKeyPressed(SDL_SCANCODE_SPACE).
+//  [X] Platform: Gamepad support. Enabled with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
+// Missing features:
+//  [ ] Platform: SDL2 handling of IME under Windows appears to be broken and it explicitly disable the regular Windows IME. You can restore Windows IME by compiling SDL with SDL_DISABLE_WINDOWS_IME.
+
+// You can copy and use unmodified imgui_impl_* files in your project. See main.cpp for an example of using this.
+// If you are new to dear imgui, read examples/README.txt and read the documentation at the top of imgui.cpp.
+// https://github.com/ocornut/imgui
+
+#pragma once
+#include "imgui.h"      // IMGUI_IMPL_API
+
+struct SDL_Window;
+typedef union SDL_Event SDL_Event;
+
+IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForOpenGL(SDL_Window* window, void* sdl_gl_context);
+IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForVulkan(SDL_Window* window);
+IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForD3D(SDL_Window* window);
+IMGUI_IMPL_API bool     ImGui_ImplSDL2_InitForMetal(SDL_Window* window);
+IMGUI_IMPL_API void     ImGui_ImplSDL2_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplSDL2_NewFrame(SDL_Window* window);
+IMGUI_IMPL_API bool     ImGui_ImplSDL2_ProcessEvent(const SDL_Event* event);

include/imgui/imgui_internal.h

+// dear imgui, v1.77 WIP
+// (internal structures/api)
+
+// You may use this file to debug, understand or extend ImGui features but we don't provide any guarantee of forward compatibility!
+// Set:
+//   #define IMGUI_DEFINE_MATH_OPERATORS
+// To implement maths operators for ImVec2 (disabled by default to not collide with using IM_VEC2_CLASS_EXTRA along with your own math types+operators)
+
+/*
+
+Index of this file:
+// Header mess
+// Forward declarations
+// STB libraries includes
+// Context pointer
+// Generic helpers
+// Misc data structures
+// Main imgui context
+// Tab bar, tab item
+// Internal API
+
+*/
+
+#pragma once
+#ifndef IMGUI_DISABLE
+
+//-----------------------------------------------------------------------------
+// Header mess
+//-----------------------------------------------------------------------------
+
+#ifndef IMGUI_VERSION
+#error Must include imgui.h before imgui_internal.h
+#endif
+
+#include <stdio.h>      // FILE*, sscanf
+#include <stdlib.h>     // NULL, malloc, free, qsort, atoi, atof
+#include <math.h>       // sqrtf, fabsf, fmodf, powf, floorf, ceilf, cosf, sinf
+#include <limits.h>     // INT_MIN, INT_MAX
+
+// Visual Studio warnings
+#ifdef _MSC_VER
+#pragma warning (push)
+#pragma warning (disable: 4251) // class 'xxx' needs to have dll-interface to be used by clients of struct 'xxx' // when IMGUI_API is set to__declspec(dllexport)
+#endif
+
+// Clang/GCC warnings with -Weverything
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"        // for stb_textedit.h
+#pragma clang diagnostic ignored "-Wmissing-prototypes"     // for stb_textedit.h
+#pragma clang diagnostic ignored "-Wold-style-cast"
+#if __has_warning("-Wzero-as-null-pointer-constant")
+#pragma clang diagnostic ignored "-Wzero-as-null-pointer-constant"
+#endif
+#if __has_warning("-Wdouble-promotion")
+#pragma clang diagnostic ignored "-Wdouble-promotion"
+#endif
+#elif defined(__GNUC__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wpragmas"                  // warning: unknown option after '#pragma GCC diagnostic' kind
+#pragma GCC diagnostic ignored "-Wclass-memaccess"          // [__GNUC__ >= 8] warning: 'memset/memcpy' clearing/writing an object of type 'xxxx' with no trivial copy-assignment; use assignment or value-initialization instead
+#endif
+
+// Legacy defines
+#ifdef IMGUI_DISABLE_FORMAT_STRING_FUNCTIONS                // Renamed in 1.74
+#error Use IMGUI_DISABLE_DEFAULT_FORMAT_FUNCTIONS
+#endif
+#ifdef IMGUI_DISABLE_MATH_FUNCTIONS                         // Renamed in 1.74
+#error Use IMGUI_DISABLE_DEFAULT_MATH_FUNCTIONS
+#endif
+
+//-----------------------------------------------------------------------------
+// Forward declarations
+//-----------------------------------------------------------------------------
+
+struct ImBitVector;                 // Store 1-bit per value
+struct ImRect;                      // An axis-aligned rectangle (2 points)
+struct ImDrawDataBuilder;           // Helper to build a ImDrawData instance
+struct ImDrawListSharedData;        // Data shared between all ImDrawList instances
+struct ImGuiColorMod;               // Stacked color modifier, backup of modified data so we can restore it
+struct ImGuiColumnData;             // Storage data for a single column
+struct ImGuiColumns;                // Storage data for a columns set
+struct ImGuiContext;                // Main Dear ImGui context
+struct ImGuiDataTypeInfo;           // Type information associated to a ImGuiDataType enum
+struct ImGuiGroupData;              // Stacked storage data for BeginGroup()/EndGroup()
+struct ImGuiInputTextState;         // Internal state of the currently focused/edited text input box
+struct ImGuiItemHoveredDataBackup;  // Backup and restore IsItemHovered() internal data
+struct ImGuiMenuColumns;            // Simple column measurement, currently used for MenuItem() only
+struct ImGuiNavMoveResult;          // Result of a gamepad/keyboard directional navigation move query result
+struct ImGuiNextWindowData;         // Storage for SetNextWindow** functions
+struct ImGuiNextItemData;           // Storage for SetNextItem** functions
+struct ImGuiPopupData;              // Storage for current popup stack
+struct ImGuiSettingsHandler;        // Storage for one type registered in the .ini file
+struct ImGuiStyleMod;               // Stacked style modifier, backup of modified data so we can restore it
+struct ImGuiTabBar;                 // Storage for a tab bar
+struct ImGuiTabItem;                // Storage for a tab item (within a tab bar)
+struct ImGuiWindow;                 // Storage for one window
+struct ImGuiWindowTempData;         // Temporary storage for one window (that's the data which in theory we could ditch at the end of the frame)
+struct ImGuiWindowSettings;         // Storage for a window .ini settings (we keep one of those even if the actual window wasn't instanced during this session)
+
+// Use your programming IDE "Go to definition" facility on the names of the center columns to find the actual flags/enum lists.
+typedef int ImGuiLayoutType;            // -> enum ImGuiLayoutType_         // Enum: Horizontal or vertical
+typedef int ImGuiButtonFlags;           // -> enum ImGuiButtonFlags_        // Flags: for ButtonEx(), ButtonBehavior()
+typedef int ImGuiColumnsFlags;          // -> enum ImGuiColumnsFlags_       // Flags: BeginColumns()
+typedef int ImGuiDragFlags;             // -> enum ImGuiDragFlags_          // Flags: for DragBehavior()
+typedef int ImGuiItemFlags;             // -> enum ImGuiItemFlags_          // Flags: for PushItemFlag()
+typedef int ImGuiItemStatusFlags;       // -> enum ImGuiItemStatusFlags_    // Flags: for DC.LastItemStatusFlags
+typedef int ImGuiNavHighlightFlags;     // -> enum ImGuiNavHighlightFlags_  // Flags: for RenderNavHighlight()
+typedef int ImGuiNavDirSourceFlags;     // -> enum ImGuiNavDirSourceFlags_  // Flags: for GetNavInputAmount2d()
+typedef int ImGuiNavMoveFlags;          // -> enum ImGuiNavMoveFlags_       // Flags: for navigation requests
+typedef int ImGuiNextItemDataFlags;     // -> enum ImGuiNextItemDataFlags_  // Flags: for SetNextItemXXX() functions
+typedef int ImGuiNextWindowDataFlags;   // -> enum ImGuiNextWindowDataFlags_// Flags: for SetNextWindowXXX() functions
+typedef int ImGuiSeparatorFlags;        // -> enum ImGuiSeparatorFlags_     // Flags: for SeparatorEx()
+typedef int ImGuiSliderFlags;           // -> enum ImGuiSliderFlags_        // Flags: for SliderBehavior()
+typedef int ImGuiTextFlags;             // -> enum ImGuiTextFlags_          // Flags: for TextEx()
+typedef int ImGuiTooltipFlags;          // -> enum ImGuiTooltipFlags_       // Flags: for BeginTooltipEx()
+
+//-------------------------------------------------------------------------
+// STB libraries includes
+//-------------------------------------------------------------------------
+
+namespace ImStb
+{
+
+#undef STB_TEXTEDIT_STRING
+#undef STB_TEXTEDIT_CHARTYPE
+#define STB_TEXTEDIT_STRING             ImGuiInputTextState
+#define STB_TEXTEDIT_CHARTYPE           ImWchar
+#define STB_TEXTEDIT_GETWIDTH_NEWLINE   -1.0f
+#define STB_TEXTEDIT_UNDOSTATECOUNT     99
+#define STB_TEXTEDIT_UNDOCHARCOUNT      999
+#include "imstb_textedit.h"
+
+} // namespace ImStb
+
+//-----------------------------------------------------------------------------
+// Context pointer
+//-----------------------------------------------------------------------------
+
+#ifndef GImGui
+extern IMGUI_API ImGuiContext* GImGui;  // Current implicit context pointer
+#endif
+
+//-----------------------------------------------------------------------------
+// Macros
+//-----------------------------------------------------------------------------
+
+// Debug Logging
+#ifndef IMGUI_DEBUG_LOG
+#define IMGUI_DEBUG_LOG(_FMT,...)       printf("[%05d] " _FMT, GImGui->FrameCount, __VA_ARGS__)
+#endif
+
+// Static Asserts
+#if (__cplusplus >= 201100)
+#define IM_STATIC_ASSERT(_COND)         static_assert(_COND, "")
+#else
+#define IM_STATIC_ASSERT(_COND)         typedef char static_assertion_##__line__[(_COND)?1:-1]
+#endif
+
+// "Paranoid" Debug Asserts are meant to only be enabled during specific debugging/work, otherwise would slow down the code too much.
+// We currently don't have many of those so the effect is currently negligible, but onward intent to add more aggressive ones in the code.
+//#define IMGUI_DEBUG_PARANOID
+#ifdef IMGUI_DEBUG_PARANOID
+#define IM_ASSERT_PARANOID(_EXPR)       IM_ASSERT(_EXPR)
+#else
+#define IM_ASSERT_PARANOID(_EXPR)
+#endif
+
+// Error handling
+// Down the line in some frameworks/languages we would like to have a way to redirect those to the programmer and recover from more faults.
+#ifndef IM_ASSERT_USER_ERROR
+#define IM_ASSERT_USER_ERROR(_EXP,_MSG) IM_ASSERT((_EXP) && _MSG)   // Recoverable User Error
+#endif
+
+// Misc Macros
+#define IM_PI                           3.14159265358979323846f
+#ifdef _WIN32
+#define IM_NEWLINE                      "\r\n"   // Play it nice with Windows users (Update: since 2018-05, Notepad finally appears to support Unix-style carriage returns!)
+#else
+#define IM_NEWLINE                      "\n"
+#endif
+#define IM_TABSIZE                      (4)
+#define IM_F32_TO_INT8_UNBOUND(_VAL)    ((int)((_VAL) * 255.0f + ((_VAL)>=0 ? 0.5f : -0.5f)))   // Unsaturated, for display purpose
+#define IM_F32_TO_INT8_SAT(_VAL)        ((int)(ImSaturate(_VAL) * 255.0f + 0.5f))               // Saturated, always output 0..255
+#define IM_FLOOR(_VAL)                  ((float)(int)(_VAL))                                    // ImFloor() is not inlined in MSVC debug builds
+#define IM_ROUND(_VAL)                  ((float)(int)((_VAL) + 0.5f))                           //
+
+// Enforce cdecl calling convention for functions called by the standard library, in case compilation settings changed the default to e.g. __vectorcall
+#ifdef _MSC_VER
+#define IMGUI_CDECL __cdecl
+#else
+#define IMGUI_CDECL
+#endif
+
+//-----------------------------------------------------------------------------
+// Generic helpers
+// Note that the ImXXX helpers functions are lower-level than ImGui functions.
+// ImGui functions or the ImGui context are never called/used from other ImXXX functions.
+//-----------------------------------------------------------------------------
+// - Helpers: Misc
+// - Helpers: Bit manipulation
+// - Helpers: String, Formatting
+// - Helpers: UTF-8 <> wchar conversions
+// - Helpers: ImVec2/ImVec4 operators
+// - Helpers: Maths
+// - Helpers: Geometry
+// - Helpers: Bit arrays
+// - Helper: ImBitVector
+// - Helper: ImPool<>
+// - Helper: ImChunkStream<>
+//-----------------------------------------------------------------------------
+
+// Helpers: Misc
+#define ImQsort         qsort
+IMGUI_API ImU32         ImHashData(const void* data, size_t data_size, ImU32 seed = 0);
+IMGUI_API ImU32         ImHashStr(const char* data, size_t data_size = 0, ImU32 seed = 0);
+#ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
+static inline ImU32     ImHash(const void* data, int size, ImU32 seed = 0) { return size ? ImHashData(data, (size_t)size, seed) : ImHashStr((const char*)data, 0, seed); } // [moved to ImHashStr/ImHashData in 1.68]
+#endif
+
+// Helpers: Color Blending
+IMGUI_API ImU32         ImAlphaBlendColors(ImU32 col_a, ImU32 col_b);
+
+// Helpers: Bit manipulation
+static inline bool      ImIsPowerOfTwo(int v)           { return v != 0 && (v & (v - 1)) == 0; }
+static inline int       ImUpperPowerOfTwo(int v)        { v--; v |= v >> 1; v |= v >> 2; v |= v >> 4; v |= v >> 8; v |= v >> 16; v++; return v; }
+
+// Helpers: String, Formatting
+IMGUI_API int           ImStricmp(const char* str1, const char* str2);
+IMGUI_API int           ImStrnicmp(const char* str1, const char* str2, size_t count);
+IMGUI_API void          ImStrncpy(char* dst, const char* src, size_t count);
+IMGUI_API char*         ImStrdup(const char* str);
+IMGUI_API char*         ImStrdupcpy(char* dst, size_t* p_dst_size, const char* str);
+IMGUI_API const char*   ImStrchrRange(const char* str_begin, const char* str_end, char c);
+IMGUI_API int           ImStrlenW(const ImWchar* str);
+IMGUI_API const char*   ImStreolRange(const char* str, const char* str_end);                // End end-of-line
+IMGUI_API const ImWchar*ImStrbolW(const ImWchar* buf_mid_line, const ImWchar* buf_begin);   // Find beginning-of-line
+IMGUI_API const char*   ImStristr(const char* haystack, const char* haystack_end, const char* needle, const char* needle_end);
+IMGUI_API void          ImStrTrimBlanks(char* str);
+IMGUI_API const char*   ImStrSkipBlank(const char* str);
+IMGUI_API int           ImFormatString(char* buf, size_t buf_size, const char* fmt, ...) IM_FMTARGS(3);
+IMGUI_API int           ImFormatStringV(char* buf, size_t buf_size, const char* fmt, va_list args) IM_FMTLIST(3);
+IMGUI_API const char*   ImParseFormatFindStart(const char* format);
+IMGUI_API const char*   ImParseFormatFindEnd(const char* format);
+IMGUI_API const char*   ImParseFormatTrimDecorations(const char* format, char* buf, size_t buf_size);
+IMGUI_API int           ImParseFormatPrecision(const char* format, int default_value);
+static inline bool      ImCharIsBlankA(char c)          { return c == ' ' || c == '\t'; }
+static inline bool      ImCharIsBlankW(unsigned int c)  { return c == ' ' || c == '\t' || c == 0x3000; }
+
+// Helpers: UTF-8 <> wchar conversions
+IMGUI_API int           ImTextStrToUtf8(char* buf, int buf_size, const ImWchar* in_text, const ImWchar* in_text_end);      // return output UTF-8 bytes count
+IMGUI_API int           ImTextCharFromUtf8(unsigned int* out_char, const char* in_text, const char* in_text_end);          // read one character. return input UTF-8 bytes count
+IMGUI_API int           ImTextStrFromUtf8(ImWchar* buf, int buf_size, const char* in_text, const char* in_text_end, const char** in_remaining = NULL);   // return input UTF-8 bytes count
+IMGUI_API int           ImTextCountCharsFromUtf8(const char* in_text, const char* in_text_end);                            // return number of UTF-8 code-points (NOT bytes count)
+IMGUI_API int           ImTextCountUtf8BytesFromChar(const char* in_text, const char* in_text_end);                        // return number of bytes to express one char in UTF-8
+IMGUI_API int           ImTextCountUtf8BytesFromStr(const ImWchar* in_text, const ImWchar* in_text_end);                   // return number of bytes to express string in UTF-8
+
+// Helpers: ImVec2/ImVec4 operators
+// We are keeping those disabled by default so they don't leak in user space, to allow user enabling implicit cast operators between ImVec2 and their own types (using IM_VEC2_CLASS_EXTRA etc.)
+// We unfortunately don't have a unary- operator for ImVec2 because this would needs to be defined inside the class itself.
+#ifdef IMGUI_DEFINE_MATH_OPERATORS
+static inline ImVec2 operator*(const ImVec2& lhs, const float rhs)              { return ImVec2(lhs.x*rhs, lhs.y*rhs); }
+static inline ImVec2 operator/(const ImVec2& lhs, const float rhs)              { return ImVec2(lhs.x/rhs, lhs.y/rhs); }
+static inline ImVec2 operator+(const ImVec2& lhs, const ImVec2& rhs)            { return ImVec2(lhs.x+rhs.x, lhs.y+rhs.y); }
+static inline ImVec2 operator-(const ImVec2& lhs, const ImVec2& rhs)            { return ImVec2(lhs.x-rhs.x, lhs.y-rhs.y); }
+static inline ImVec2 operator*(const ImVec2& lhs, const ImVec2& rhs)            { return ImVec2(lhs.x*rhs.x, lhs.y*rhs.y); }
+static inline ImVec2 operator/(const ImVec2& lhs, const ImVec2& rhs)            { return ImVec2(lhs.x/rhs.x, lhs.y/rhs.y); }
+static inline ImVec2& operator*=(ImVec2& lhs, const float rhs)                  { lhs.x *= rhs; lhs.y *= rhs; return lhs; }
+static inline ImVec2& operator/=(ImVec2& lhs, const float rhs)                  { lhs.x /= rhs; lhs.y /= rhs; return lhs; }
+static inline ImVec2& operator+=(ImVec2& lhs, const ImVec2& rhs)                { lhs.x += rhs.x; lhs.y += rhs.y; return lhs; }
+static inline ImVec2& operator-=(ImVec2& lhs, const ImVec2& rhs)                { lhs.x -= rhs.x; lhs.y -= rhs.y; return lhs; }
+static inline ImVec2& operator*=(ImVec2& lhs, const ImVec2& rhs)                { lhs.x *= rhs.x; lhs.y *= rhs.y; return lhs; }
+static inline ImVec2& operator/=(ImVec2& lhs, const ImVec2& rhs)                { lhs.x /= rhs.x; lhs.y /= rhs.y; return lhs; }
+static inline ImVec4 operator+(const ImVec4& lhs, const ImVec4& rhs)            { return ImVec4(lhs.x+rhs.x, lhs.y+rhs.y, lhs.z+rhs.z, lhs.w+rhs.w); }
+static inline ImVec4 operator-(const ImVec4& lhs, const ImVec4& rhs)            { return ImVec4(lhs.x-rhs.x, lhs.y-rhs.y, lhs.z-rhs.z, lhs.w-rhs.w); }
+static inline ImVec4 operator*(const ImVec4& lhs, const ImVec4& rhs)            { return ImVec4(lhs.x*rhs.x, lhs.y*rhs.y, lhs.z*rhs.z, lhs.w*rhs.w); }
+#endif
+
+// Helpers: File System
+#ifdef IMGUI_DISABLE_FILE_FUNCTIONS
+#define IMGUI_DISABLE_DEFAULT_FILE_FUNCTIONS
+typedef void* ImFileHandle;
+static inline ImFileHandle  ImFileOpen(const char*, const char*)                    { return NULL; }
+static inline bool          ImFileClose(ImFileHandle)                               { return false; }
+static inline ImU64         ImFileGetSize(ImFileHandle)                             { return (ImU64)-1; }
+static inline ImU64         ImFileRead(void*, ImU64, ImU64, ImFileHandle)           { return 0; }
+static inline ImU64         ImFileWrite(const void*, ImU64, ImU64, ImFileHandle)    { return 0; }
+#endif
+
+#ifndef IMGUI_DISABLE_DEFAULT_FILE_FUNCTIONS
+typedef FILE* ImFileHandle;
+IMGUI_API ImFileHandle      ImFileOpen(const char* filename, const char* mode);
+IMGUI_API bool              ImFileClose(ImFileHandle file);
+IMGUI_API ImU64             ImFileGetSize(ImFileHandle file);
+IMGUI_API ImU64             ImFileRead(void* data, ImU64 size, ImU64 count, ImFileHandle file);
+IMGUI_API ImU64             ImFileWrite(const void* data, ImU64 size, ImU64 count, ImFileHandle file);
+#else
+#define IMGUI_DISABLE_TTY_FUNCTIONS // Can't use stdout, fflush if we are not using default file functions
+#endif
+IMGUI_API void*             ImFileLoadToMemory(const char* filename, const char* mode, size_t* out_file_size = NULL, int padding_bytes = 0);
+
+// Helpers: Maths
+// - Wrapper for standard libs functions. (Note that imgui_demo.cpp does _not_ use them to keep the code easy to copy)
+#ifndef IMGUI_DISABLE_DEFAULT_MATH_FUNCTIONS
+#define ImFabs(X)           fabsf(X)
+#define ImSqrt(X)           sqrtf(X)
+#define ImFmod(X, Y)        fmodf((X), (Y))
+#define ImCos(X)            cosf(X)
+#define ImSin(X)            sinf(X)
+#define ImAcos(X)           acosf(X)
+#define ImAtan2(Y, X)       atan2f((Y), (X))
+#define ImAtof(STR)         atof(STR)
+#define ImFloorStd(X)       floorf(X)           // We already uses our own ImFloor() { return (float)(int)v } internally so the standard one wrapper is named differently (it's used by e.g. stb_truetype)
+#define ImCeil(X)           ceilf(X)
+static inline float  ImPow(float x, float y)    { return powf(x, y); }          // DragBehaviorT/SliderBehaviorT uses ImPow with either float/double and need the precision
+static inline double ImPow(double x, double y)  { return pow(x, y); }
+#endif
+// - ImMin/ImMax/ImClamp/ImLerp/ImSwap are used by widgets which support variety of types: signed/unsigned int/long long float/double
+// (Exceptionally using templates here but we could also redefine them for those types)
+template<typename T> static inline T ImMin(T lhs, T rhs)                        { return lhs < rhs ? lhs : rhs; }
+template<typename T> static inline T ImMax(T lhs, T rhs)                        { return lhs >= rhs ? lhs : rhs; }
+template<typename T> static inline T ImClamp(T v, T mn, T mx)                   { return (v < mn) ? mn : (v > mx) ? mx : v; }
+template<typename T> static inline T ImLerp(T a, T b, float t)                  { return (T)(a + (b - a) * t); }
+template<typename T> static inline void ImSwap(T& a, T& b)                      { T tmp = a; a = b; b = tmp; }
+template<typename T> static inline T ImAddClampOverflow(T a, T b, T mn, T mx)   { if (b < 0 && (a < mn - b)) return mn; if (b > 0 && (a > mx - b)) return mx; return a + b; }
+template<typename T> static inline T ImSubClampOverflow(T a, T b, T mn, T mx)   { if (b > 0 && (a < mn + b)) return mn; if (b < 0 && (a > mx + b)) return mx; return a - b; }
+// - Misc maths helpers
+static inline ImVec2 ImMin(const ImVec2& lhs, const ImVec2& rhs)                { return ImVec2(lhs.x < rhs.x ? lhs.x : rhs.x, lhs.y < rhs.y ? lhs.y : rhs.y); }
+static inline ImVec2 ImMax(const ImVec2& lhs, const ImVec2& rhs)                { return ImVec2(lhs.x >= rhs.x ? lhs.x : rhs.x, lhs.y >= rhs.y ? lhs.y : rhs.y); }
+static inline ImVec2 ImClamp(const ImVec2& v, const ImVec2& mn, ImVec2 mx)      { return ImVec2((v.x < mn.x) ? mn.x : (v.x > mx.x) ? mx.x : v.x, (v.y < mn.y) ? mn.y : (v.y > mx.y) ? mx.y : v.y); }
+static inline ImVec2 ImLerp(const ImVec2& a, const ImVec2& b, float t)          { return ImVec2(a.x + (b.x - a.x) * t, a.y + (b.y - a.y) * t); }
+static inline ImVec2 ImLerp(const ImVec2& a, const ImVec2& b, const ImVec2& t)  { return ImVec2(a.x + (b.x - a.x) * t.x, a.y + (b.y - a.y) * t.y); }
+static inline ImVec4 ImLerp(const ImVec4& a, const ImVec4& b, float t)          { return ImVec4(a.x + (b.x - a.x) * t, a.y + (b.y - a.y) * t, a.z + (b.z - a.z) * t, a.w + (b.w - a.w) * t); }
+static inline float  ImSaturate(float f)                                        { return (f < 0.0f) ? 0.0f : (f > 1.0f) ? 1.0f : f; }
+static inline float  ImLengthSqr(const ImVec2& lhs)                             { return lhs.x*lhs.x + lhs.y*lhs.y; }
+static inline float  ImLengthSqr(const ImVec4& lhs)                             { return lhs.x*lhs.x + lhs.y*lhs.y + lhs.z*lhs.z + lhs.w*lhs.w; }
+static inline float  ImInvLength(const ImVec2& lhs, float fail_value)           { float d = lhs.x*lhs.x + lhs.y*lhs.y; if (d > 0.0f) return 1.0f / ImSqrt(d); return fail_value; }
+static inline float  ImFloor(float f)                                           { return (float)(int)(f); }
+static inline ImVec2 ImFloor(const ImVec2& v)                                   { return ImVec2((float)(int)(v.x), (float)(int)(v.y)); }
+static inline int    ImModPositive(int a, int b)                                { return (a + b) % b; }
+static inline float  ImDot(const ImVec2& a, const ImVec2& b)                    { return a.x * b.x + a.y * b.y; }
+static inline ImVec2 ImRotate(const ImVec2& v, float cos_a, float sin_a)        { return ImVec2(v.x * cos_a - v.y * sin_a, v.x * sin_a + v.y * cos_a); }
+static inline float  ImLinearSweep(float current, float target, float speed)    { if (current < target) return ImMin(current + speed, target); if (current > target) return ImMax(current - speed, target); return current; }
+static inline ImVec2 ImMul(const ImVec2& lhs, const ImVec2& rhs)                { return ImVec2(lhs.x * rhs.x, lhs.y * rhs.y); }
+
+// Helpers: Geometry
+IMGUI_API ImVec2     ImBezierCalc(const ImVec2& p1, const ImVec2& p2, const ImVec2& p3, const ImVec2& p4, float t);                                         // Cubic Bezier
+IMGUI_API ImVec2     ImBezierClosestPoint(const ImVec2& p1, const ImVec2& p2, const ImVec2& p3, const ImVec2& p4, const ImVec2& p, int num_segments);       // For curves with explicit number of segments
+IMGUI_API ImVec2     ImBezierClosestPointCasteljau(const ImVec2& p1, const ImVec2& p2, const ImVec2& p3, const ImVec2& p4, const ImVec2& p, float tess_tol);// For auto-tessellated curves you can use tess_tol = style.CurveTessellationTol
+IMGUI_API ImVec2     ImLineClosestPoint(const ImVec2& a, const ImVec2& b, const ImVec2& p);
+IMGUI_API bool       ImTriangleContainsPoint(const ImVec2& a, const ImVec2& b, const ImVec2& c, const ImVec2& p);
+IMGUI_API ImVec2     ImTriangleClosestPoint(const ImVec2& a, const ImVec2& b, const ImVec2& c, const ImVec2& p);
+IMGUI_API void       ImTriangleBarycentricCoords(const ImVec2& a, const ImVec2& b, const ImVec2& c, const ImVec2& p, float& out_u, float& out_v, float& out_w);
+inline float         ImTriangleArea(const ImVec2& a, const ImVec2& b, const ImVec2& c) { return ImFabs((a.x * (b.y - c.y)) + (b.x * (c.y - a.y)) + (c.x * (a.y - b.y))) * 0.5f; }
+IMGUI_API ImGuiDir   ImGetDirQuadrantFromDelta(float dx, float dy);
+
+// Helpers: Bit arrays
+inline bool          ImBitArrayTestBit(const ImU32* arr, int n)         { ImU32 mask = (ImU32)1 << (n & 31); return (arr[n >> 5] & mask) != 0; }
+inline void          ImBitArrayClearBit(ImU32* arr, int n)              { ImU32 mask = (ImU32)1 << (n & 31); arr[n >> 5] &= ~mask; }
+inline void          ImBitArraySetBit(ImU32* arr, int n)                { ImU32 mask = (ImU32)1 << (n & 31); arr[n >> 5] |= mask; }
+inline void          ImBitArraySetBitRange(ImU32* arr, int n, int n2)
+{
+    while (n <= n2)
+    {
+        int a_mod = (n & 31);
+        int b_mod = ((n2 >= n + 31) ? 31 : (n2 & 31)) + 1;
+        ImU32 mask = (ImU32)(((ImU64)1 << b_mod) - 1) & ~(ImU32)(((ImU64)1 << a_mod) - 1);
+        arr[n >> 5] |= mask;
+        n = (n + 32) & ~31;
+    }
+}
+
+// Helper: ImBitVector
+// Store 1-bit per value.
+struct IMGUI_API ImBitVector
+{
+    ImVector<ImU32> Storage;
+    void            Create(int sz)              { Storage.resize((sz + 31) >> 5); memset(Storage.Data, 0, (size_t)Storage.Size * sizeof(Storage.Data[0])); }
+    void            Clear()                     { Storage.clear(); }
+    bool            TestBit(int n) const        { IM_ASSERT(n < (Storage.Size << 5)); return ImBitArrayTestBit(Storage.Data, n); }
+    void            SetBit(int n)               { IM_ASSERT(n < (Storage.Size << 5)); ImBitArraySetBit(Storage.Data, n); }
+    void            ClearBit(int n)             { IM_ASSERT(n < (Storage.Size << 5)); ImBitArrayClearBit(Storage.Data, n); }
+};
+
+// Helper: ImPool<>
+// Basic keyed storage for contiguous instances, slow/amortized insertion, O(1) indexable, O(Log N) queries by ID over a dense/hot buffer,
+// Honor constructor/destructor. Add/remove invalidate all pointers. Indexes have the same lifetime as the associated object.
+typedef int ImPoolIdx;
+template<typename T>
+struct IMGUI_API ImPool
+{
+    ImVector<T>     Buf;        // Contiguous data
+    ImGuiStorage    Map;        // ID->Index
+    ImPoolIdx       FreeIdx;    // Next free idx to use
+
+    ImPool()    { FreeIdx = 0; }
+    ~ImPool()   { Clear(); }
+    T*          GetByKey(ImGuiID key)               { int idx = Map.GetInt(key, -1); return (idx != -1) ? &Buf[idx] : NULL; }
+    T*          GetByIndex(ImPoolIdx n)             { return &Buf[n]; }
+    ImPoolIdx   GetIndex(const T* p) const          { IM_ASSERT(p >= Buf.Data && p < Buf.Data + Buf.Size); return (ImPoolIdx)(p - Buf.Data); }
+    T*          GetOrAddByKey(ImGuiID key)          { int* p_idx = Map.GetIntRef(key, -1); if (*p_idx != -1) return &Buf[*p_idx]; *p_idx = FreeIdx; return Add(); }
+    bool        Contains(const T* p) const          { return (p >= Buf.Data && p < Buf.Data + Buf.Size); }
+    void        Clear()                             { for (int n = 0; n < Map.Data.Size; n++) { int idx = Map.Data[n].val_i; if (idx != -1) Buf[idx].~T(); } Map.Clear(); Buf.clear(); FreeIdx = 0; }
+    T*          Add()                               { int idx = FreeIdx; if (idx == Buf.Size) { Buf.resize(Buf.Size + 1); FreeIdx++; } else { FreeIdx = *(int*)&Buf[idx]; } IM_PLACEMENT_NEW(&Buf[idx]) T(); return &Buf[idx]; }
+    void        Remove(ImGuiID key, const T* p)     { Remove(key, GetIndex(p)); }
+    void        Remove(ImGuiID key, ImPoolIdx idx)  { Buf[idx].~T(); *(int*)&Buf[idx] = FreeIdx; FreeIdx = idx; Map.SetInt(key, -1); }
+    void        Reserve(int capacity)               { Buf.reserve(capacity); Map.Data.reserve(capacity); }
+    int         GetSize() const                     { return Buf.Size; }
+};
+
+// Helper: ImChunkStream<>
+// Build and iterate a contiguous stream of variable-sized structures.
+// This is used by Settings to store persistent data while reducing allocation count.
+// We store the chunk size first, and align the final size on 4 bytes boundaries (this what the '(X + 3) & ~3' statement is for)
+// The tedious/zealous amount of casting is to avoid -Wcast-align warnings.
+template<typename T>
+struct IMGUI_API ImChunkStream
+{
+    ImVector<char>  Buf;
+
+    void    clear()                     { Buf.clear(); }
+    bool    empty() const               { return Buf.Size == 0; }
+    int     size() const                { return Buf.Size; }
+    T*      alloc_chunk(size_t sz)      { size_t HDR_SZ = 4; sz = ((HDR_SZ + sz) + 3u) & ~3u; int off = Buf.Size; Buf.resize(off + (int)sz); ((int*)(void*)(Buf.Data + off))[0] = (int)sz; return (T*)(void*)(Buf.Data + off + (int)HDR_SZ); }
+    T*      begin()                     { size_t HDR_SZ = 4; if (!Buf.Data) return NULL; return (T*)(void*)(Buf.Data + HDR_SZ); }
+    T*      next_chunk(T* p)            { size_t HDR_SZ = 4; IM_ASSERT(p >= begin() && p < end()); p = (T*)(void*)((char*)(void*)p + chunk_size(p)); if (p == (T*)(void*)((char*)end() + HDR_SZ)) return (T*)0; IM_ASSERT(p < end()); return p; }
+    int     chunk_size(const T* p)      { return ((const int*)p)[-1]; }
+    T*      end()                       { return (T*)(void*)(Buf.Data + Buf.Size); }
+    int     offset_from_ptr(const T* p) { IM_ASSERT(p >= begin() && p < end()); const ptrdiff_t off = (const char*)p - Buf.Data; return (int)off; }
+    T*      ptr_from_offset(int off)    { IM_ASSERT(off >= 4 && off < Buf.Size); return (T*)(void*)(Buf.Data + off); }
+};
+
+//-----------------------------------------------------------------------------
+// Misc data structures
+//-----------------------------------------------------------------------------
+
+enum ImGuiButtonFlags_
+{
+    ImGuiButtonFlags_None                   = 0,
+    ImGuiButtonFlags_Repeat                 = 1 << 0,   // hold to repeat
+    ImGuiButtonFlags_PressedOnClick         = 1 << 1,   // return true on click (mouse down event)
+    ImGuiButtonFlags_PressedOnClickRelease  = 1 << 2,   // [Default] return true on click + release on same item <-- this is what the majority of Button are using
+    ImGuiButtonFlags_PressedOnClickReleaseAnywhere = 1 << 3, // return true on click + release even if the release event is not done while hovering the item
+    ImGuiButtonFlags_PressedOnRelease       = 1 << 4,   // return true on release (default requires click+release)
+    ImGuiButtonFlags_PressedOnDoubleClick   = 1 << 5,   // return true on double-click (default requires click+release)
+    ImGuiButtonFlags_PressedOnDragDropHold  = 1 << 6,   // return true when held into while we are drag and dropping another item (used by e.g. tree nodes, collapsing headers)
+    ImGuiButtonFlags_FlattenChildren        = 1 << 7,   // allow interactions even if a child window is overlapping
+    ImGuiButtonFlags_AllowItemOverlap       = 1 << 8,   // require previous frame HoveredId to either match id or be null before being usable, use along with SetItemAllowOverlap()
+    ImGuiButtonFlags_DontClosePopups        = 1 << 9,   // disable automatically closing parent popup on press // [UNUSED]
+    ImGuiButtonFlags_Disabled               = 1 << 10,  // disable interactions
+    ImGuiButtonFlags_AlignTextBaseLine      = 1 << 11,  // vertically align button to match text baseline - ButtonEx() only // FIXME: Should be removed and handled by SmallButton(), not possible currently because of DC.CursorPosPrevLine
+    ImGuiButtonFlags_NoKeyModifiers         = 1 << 12,  // disable mouse interaction if a key modifier is held
+    ImGuiButtonFlags_NoHoldingActiveId      = 1 << 13,  // don't set ActiveId while holding the mouse (ImGuiButtonFlags_PressedOnClick only)
+    ImGuiButtonFlags_NoNavFocus             = 1 << 14,  // don't override navigation focus when activated
+    ImGuiButtonFlags_NoHoveredOnFocus       = 1 << 15,  // don't report as hovered when nav focus is on this item
+    ImGuiButtonFlags_MouseButtonLeft        = 1 << 16,  // [Default] react on left mouse button
+    ImGuiButtonFlags_MouseButtonRight       = 1 << 17,  // react on right mouse button
+    ImGuiButtonFlags_MouseButtonMiddle      = 1 << 18,  // react on center mouse button
+
+    ImGuiButtonFlags_MouseButtonMask_       = ImGuiButtonFlags_MouseButtonLeft | ImGuiButtonFlags_MouseButtonRight | ImGuiButtonFlags_MouseButtonMiddle,
+    ImGuiButtonFlags_MouseButtonShift_      = 16,
+    ImGuiButtonFlags_MouseButtonDefault_    = ImGuiButtonFlags_MouseButtonLeft,
+    ImGuiButtonFlags_PressedOnMask_         = ImGuiButtonFlags_PressedOnClick | ImGuiButtonFlags_PressedOnClickRelease | ImGuiButtonFlags_PressedOnClickReleaseAnywhere | ImGuiButtonFlags_PressedOnRelease | ImGuiButtonFlags_PressedOnDoubleClick | ImGuiButtonFlags_PressedOnDragDropHold,
+    ImGuiButtonFlags_PressedOnDefault_      = ImGuiButtonFlags_PressedOnClickRelease
+};
+
+enum ImGuiSliderFlags_
+{
+    ImGuiSliderFlags_None                   = 0,
+    ImGuiSliderFlags_Vertical               = 1 << 0
+};
+
+enum ImGuiDragFlags_
+{
+    ImGuiDragFlags_None                     = 0,
+    ImGuiDragFlags_Vertical                 = 1 << 0
+};
+
+enum ImGuiColumnsFlags_
+{
+    // Default: 0
+    ImGuiColumnsFlags_None                  = 0,
+    ImGuiColumnsFlags_NoBorder              = 1 << 0,   // Disable column dividers
+    ImGuiColumnsFlags_NoResize              = 1 << 1,   // Disable resizing columns when clicking on the dividers
+    ImGuiColumnsFlags_NoPreserveWidths      = 1 << 2,   // Disable column width preservation when adjusting columns
+    ImGuiColumnsFlags_NoForceWithinWindow   = 1 << 3,   // Disable forcing columns to fit within window
+    ImGuiColumnsFlags_GrowParentContentsSize= 1 << 4    // (WIP) Restore pre-1.51 behavior of extending the parent window contents size but _without affecting the columns width at all_. Will eventually remove.
+};
+
+// Extend ImGuiSelectableFlags_
+enum ImGuiSelectableFlagsPrivate_
+{
+    // NB: need to be in sync with last value of ImGuiSelectableFlags_
+    ImGuiSelectableFlags_NoHoldingActiveID  = 1 << 20,
+    ImGuiSelectableFlags_SelectOnClick      = 1 << 21,  // Override button behavior to react on Click (default is Click+Release)
+    ImGuiSelectableFlags_SelectOnRelease    = 1 << 22,  // Override button behavior to react on Release (default is Click+Release)
+    ImGuiSelectableFlags_SpanAvailWidth     = 1 << 23,  // Span all avail width even if we declared less for layout purpose. FIXME: We may be able to remove this (added in 6251d379, 2bcafc86 for menus)
+    ImGuiSelectableFlags_DrawHoveredWhenHeld= 1 << 24,  // Always show active when held, even is not hovered. This concept could probably be renamed/formalized somehow.
+    ImGuiSelectableFlags_SetNavIdOnHover    = 1 << 25
+};
+
+// Extend ImGuiTreeNodeFlags_
+enum ImGuiTreeNodeFlagsPrivate_
+{
+    ImGuiTreeNodeFlags_ClipLabelForTrailingButton = 1 << 20
+};
+
+enum ImGuiSeparatorFlags_
+{
+    ImGuiSeparatorFlags_None                = 0,
+    ImGuiSeparatorFlags_Horizontal          = 1 << 0,   // Axis default to current layout type, so generally Horizontal unless e.g. in a menu bar
+    ImGuiSeparatorFlags_Vertical            = 1 << 1,
+    ImGuiSeparatorFlags_SpanAllColumns      = 1 << 2
+};
+
+// Transient per-window flags, reset at the beginning of the frame. For child window, inherited from parent on first Begin().
+// This is going to be exposed in imgui.h when stabilized enough.
+enum ImGuiItemFlags_
+{
+    ImGuiItemFlags_None                     = 0,
+    ImGuiItemFlags_NoTabStop                = 1 << 0,  // false
+    ImGuiItemFlags_ButtonRepeat             = 1 << 1,  // false    // Button() will return true multiple times based on io.KeyRepeatDelay and io.KeyRepeatRate settings.
+    ImGuiItemFlags_Disabled                 = 1 << 2,  // false    // [BETA] Disable interactions but doesn't affect visuals yet. See github.com/ocornut/imgui/issues/211
+    ImGuiItemFlags_NoNav                    = 1 << 3,  // false
+    ImGuiItemFlags_NoNavDefaultFocus        = 1 << 4,  // false
+    ImGuiItemFlags_SelectableDontClosePopup = 1 << 5,  // false    // MenuItem/Selectable() automatically closes current Popup window
+    ImGuiItemFlags_MixedValue               = 1 << 6,  // false    // [BETA] Represent a mixed/indeterminate value, generally multi-selection where values differ. Currently only supported by Checkbox() (later should support all sorts of widgets)
+    ImGuiItemFlags_Default_                 = 0
+};
+
+// Storage for LastItem data
+enum ImGuiItemStatusFlags_
+{
+    ImGuiItemStatusFlags_None               = 0,
+    ImGuiItemStatusFlags_HoveredRect        = 1 << 0,
+    ImGuiItemStatusFlags_HasDisplayRect     = 1 << 1,
+    ImGuiItemStatusFlags_Edited             = 1 << 2,   // Value exposed by item was edited in the current frame (should match the bool return value of most widgets)
+    ImGuiItemStatusFlags_ToggledSelection   = 1 << 3,   // Set when Selectable(), TreeNode() reports toggling a selection. We can't report "Selected" because reporting the change allows us to handle clipping with less issues.
+    ImGuiItemStatusFlags_ToggledOpen        = 1 << 4,   // Set when TreeNode() reports toggling their open state.
+    ImGuiItemStatusFlags_HasDeactivated     = 1 << 5,   // Set if the widget/group is able to provide data for the ImGuiItemStatusFlags_Deactivated flag.
+    ImGuiItemStatusFlags_Deactivated        = 1 << 6    // Only valid if ImGuiItemStatusFlags_HasDeactivated is set.
+
+#ifdef IMGUI_ENABLE_TEST_ENGINE
+    , // [imgui_tests only]
+    ImGuiItemStatusFlags_Openable           = 1 << 10,  //
+    ImGuiItemStatusFlags_Opened             = 1 << 11,  //
+    ImGuiItemStatusFlags_Checkable          = 1 << 12,  //
+    ImGuiItemStatusFlags_Checked            = 1 << 13   //
+#endif
+};
+
+enum ImGuiTextFlags_
+{
+    ImGuiTextFlags_None = 0,
+    ImGuiTextFlags_NoWidthForLargeClippedText = 1 << 0
+};
+
+enum ImGuiTooltipFlags_
+{
+    ImGuiTooltipFlags_None = 0,
+    ImGuiTooltipFlags_OverridePreviousTooltip = 1 << 0      // Override will clear/ignore previously submitted tooltip (defaults to append)
+};
+
+// FIXME: this is in development, not exposed/functional as a generic feature yet.
+// Horizontal/Vertical enums are fixed to 0/1 so they may be used to index ImVec2
+enum ImGuiLayoutType_
+{
+    ImGuiLayoutType_Horizontal = 0,
+    ImGuiLayoutType_Vertical = 1
+};
+
+enum ImGuiLogType
+{
+    ImGuiLogType_None = 0,
+    ImGuiLogType_TTY,
+    ImGuiLogType_File,
+    ImGuiLogType_Buffer,
+    ImGuiLogType_Clipboard
+};
+
+// X/Y enums are fixed to 0/1 so they may be used to index ImVec2
+enum ImGuiAxis
+{
+    ImGuiAxis_None = -1,
+    ImGuiAxis_X = 0,
+    ImGuiAxis_Y = 1
+};
+
+enum ImGuiPlotType
+{
+    ImGuiPlotType_Lines,
+    ImGuiPlotType_Histogram
+};
+
+enum ImGuiInputSource
+{
+    ImGuiInputSource_None = 0,
+    ImGuiInputSource_Mouse,
+    ImGuiInputSource_Nav,
+    ImGuiInputSource_NavKeyboard,   // Only used occasionally for storage, not tested/handled by most code
+    ImGuiInputSource_NavGamepad,    // "
+    ImGuiInputSource_COUNT
+};
+
+// FIXME-NAV: Clarify/expose various repeat delay/rate
+enum ImGuiInputReadMode
+{
+    ImGuiInputReadMode_Down,
+    ImGuiInputReadMode_Pressed,
+    ImGuiInputReadMode_Released,
+    ImGuiInputReadMode_Repeat,
+    ImGuiInputReadMode_RepeatSlow,
+    ImGuiInputReadMode_RepeatFast
+};
+
+enum ImGuiNavHighlightFlags_
+{
+    ImGuiNavHighlightFlags_None         = 0,
+    ImGuiNavHighlightFlags_TypeDefault  = 1 << 0,
+    ImGuiNavHighlightFlags_TypeThin     = 1 << 1,
+    ImGuiNavHighlightFlags_AlwaysDraw   = 1 << 2,       // Draw rectangular highlight if (g.NavId == id) _even_ when using the mouse.
+    ImGuiNavHighlightFlags_NoRounding   = 1 << 3
+};
+
+enum ImGuiNavDirSourceFlags_
+{
+    ImGuiNavDirSourceFlags_None         = 0,
+    ImGuiNavDirSourceFlags_Keyboard     = 1 << 0,
+    ImGuiNavDirSourceFlags_PadDPad      = 1 << 1,
+    ImGuiNavDirSourceFlags_PadLStick    = 1 << 2
+};
+
+enum ImGuiNavMoveFlags_
+{
+    ImGuiNavMoveFlags_None                  = 0,
+    ImGuiNavMoveFlags_LoopX                 = 1 << 0,   // On failed request, restart from opposite side
+    ImGuiNavMoveFlags_LoopY                 = 1 << 1,
+    ImGuiNavMoveFlags_WrapX                 = 1 << 2,   // On failed request, request from opposite side one line down (when NavDir==right) or one line up (when NavDir==left)
+    ImGuiNavMoveFlags_WrapY                 = 1 << 3,   // This is not super useful for provided for completeness
+    ImGuiNavMoveFlags_AllowCurrentNavId     = 1 << 4,   // Allow scoring and considering the current NavId as a move target candidate. This is used when the move source is offset (e.g. pressing PageDown actually needs to send a Up move request, if we are pressing PageDown from the bottom-most item we need to stay in place)
+    ImGuiNavMoveFlags_AlsoScoreVisibleSet   = 1 << 5,   // Store alternate result in NavMoveResultLocalVisibleSet that only comprise elements that are already fully visible.
+    ImGuiNavMoveFlags_ScrollToEdge          = 1 << 6
+};
+
+enum ImGuiNavForward
+{
+    ImGuiNavForward_None,
+    ImGuiNavForward_ForwardQueued,
+    ImGuiNavForward_ForwardActive
+};
+
+enum ImGuiNavLayer
+{
+    ImGuiNavLayer_Main  = 0,    // Main scrolling layer
+    ImGuiNavLayer_Menu  = 1,    // Menu layer (access with Alt/ImGuiNavInput_Menu)
+    ImGuiNavLayer_COUNT
+};
+
+enum ImGuiPopupPositionPolicy
+{
+    ImGuiPopupPositionPolicy_Default,
+    ImGuiPopupPositionPolicy_ComboBox
+};
+
+// 1D vector (this odd construct is used to facilitate the transition between 1D and 2D, and the maintenance of some branches/patches)
+struct ImVec1
+{
+    float   x;
+    ImVec1()         { x = 0.0f; }
+    ImVec1(float _x) { x = _x; }
+};
+
+// 2D vector (half-size integer)
+struct ImVec2ih
+{
+    short   x, y;
+    ImVec2ih()                           { x = y = 0; }
+    ImVec2ih(short _x, short _y)         { x = _x; y = _y; }
+    explicit ImVec2ih(const ImVec2& rhs) { x = (short)rhs.x; y = (short)rhs.y; }
+};
+
+// 2D axis aligned bounding-box
+// NB: we can't rely on ImVec2 math operators being available here
+struct IMGUI_API ImRect
+{
+    ImVec2      Min;    // Upper-left
+    ImVec2      Max;    // Lower-right
+
+    ImRect()                                        : Min(0.0f, 0.0f), Max(0.0f, 0.0f)              {}
+    ImRect(const ImVec2& min, const ImVec2& max)    : Min(min), Max(max)                            {}
+    ImRect(const ImVec4& v)                         : Min(v.x, v.y), Max(v.z, v.w)                  {}
+    ImRect(float x1, float y1, float x2, float y2)  : Min(x1, y1), Max(x2, y2)                      {}
+
+    ImVec2      GetCenter() const                   { return ImVec2((Min.x + Max.x) * 0.5f, (Min.y + Max.y) * 0.5f); }
+    ImVec2      GetSize() const                     { return ImVec2(Max.x - Min.x, Max.y - Min.y); }
+    float       GetWidth() const                    { return Max.x - Min.x; }
+    float       GetHeight() const                   { return Max.y - Min.y; }
+    ImVec2      GetTL() const                       { return Min; }                   // Top-left
+    ImVec2      GetTR() const                       { return ImVec2(Max.x, Min.y); }  // Top-right
+    ImVec2      GetBL() const                       { return ImVec2(Min.x, Max.y); }  // Bottom-left
+    ImVec2      GetBR() const                       { return Max; }                   // Bottom-right
+    bool        Contains(const ImVec2& p) const     { return p.x     >= Min.x && p.y     >= Min.y && p.x     <  Max.x && p.y     <  Max.y; }
+    bool        Contains(const ImRect& r) const     { return r.Min.x >= Min.x && r.Min.y >= Min.y && r.Max.x <= Max.x && r.Max.y <= Max.y; }
+    bool        Overlaps(const ImRect& r) const     { return r.Min.y <  Max.y && r.Max.y >  Min.y && r.Min.x <  Max.x && r.Max.x >  Min.x; }
+    void        Add(const ImVec2& p)                { if (Min.x > p.x)     Min.x = p.x;     if (Min.y > p.y)     Min.y = p.y;     if (Max.x < p.x)     Max.x = p.x;     if (Max.y < p.y)     Max.y = p.y; }
+    void        Add(const ImRect& r)                { if (Min.x > r.Min.x) Min.x = r.Min.x; if (Min.y > r.Min.y) Min.y = r.Min.y; if (Max.x < r.Max.x) Max.x = r.Max.x; if (Max.y < r.Max.y) Max.y = r.Max.y; }
+    void        Expand(const float amount)          { Min.x -= amount;   Min.y -= amount;   Max.x += amount;   Max.y += amount; }
+    void        Expand(const ImVec2& amount)        { Min.x -= amount.x; Min.y -= amount.y; Max.x += amount.x; Max.y += amount.y; }
+    void        Translate(const ImVec2& d)          { Min.x += d.x; Min.y += d.y; Max.x += d.x; Max.y += d.y; }
+    void        TranslateX(float dx)                { Min.x += dx; Max.x += dx; }
+    void        TranslateY(float dy)                { Min.y += dy; Max.y += dy; }
+    void        ClipWith(const ImRect& r)           { Min = ImMax(Min, r.Min); Max = ImMin(Max, r.Max); }                   // Simple version, may lead to an inverted rectangle, which is fine for Contains/Overlaps test but not for display.
+    void        ClipWithFull(const ImRect& r)       { Min = ImClamp(Min, r.Min, r.Max); Max = ImClamp(Max, r.Min, r.Max); } // Full version, ensure both points are fully clipped.
+    void        Floor()                             { Min.x = IM_FLOOR(Min.x); Min.y = IM_FLOOR(Min.y); Max.x = IM_FLOOR(Max.x); Max.y = IM_FLOOR(Max.y); }
+    bool        IsInverted() const                  { return Min.x > Max.x || Min.y > Max.y; }
+};
+
+// Type information associated to one ImGuiDataType. Retrieve with DataTypeGetInfo().
+struct ImGuiDataTypeInfo
+{
+    size_t      Size;           // Size in byte
+    const char* PrintFmt;       // Default printf format for the type
+    const char* ScanFmt;        // Default scanf format for the type
+};
+
+// Extend ImGuiDataType_
+enum ImGuiDataTypePrivate_
+{
+    ImGuiDataType_String = ImGuiDataType_COUNT + 1,
+    ImGuiDataType_Pointer,
+    ImGuiDataType_ID
+};
+
+// Stacked color modifier, backup of modified data so we can restore it
+struct ImGuiColorMod
+{
+    ImGuiCol    Col;
+    ImVec4      BackupValue;
+};
+
+// Stacked style modifier, backup of modified data so we can restore it. Data type inferred from the variable.
+struct ImGuiStyleMod
+{
+    ImGuiStyleVar   VarIdx;
+    union           { int BackupInt[2]; float BackupFloat[2]; };
+    ImGuiStyleMod(ImGuiStyleVar idx, int v)     { VarIdx = idx; BackupInt[0] = v; }
+    ImGuiStyleMod(ImGuiStyleVar idx, float v)   { VarIdx = idx; BackupFloat[0] = v; }
+    ImGuiStyleMod(ImGuiStyleVar idx, ImVec2 v)  { VarIdx = idx; BackupFloat[0] = v.x; BackupFloat[1] = v.y; }
+};
+
+// Stacked storage data for BeginGroup()/EndGroup()
+struct ImGuiGroupData
+{
+    ImVec2      BackupCursorPos;
+    ImVec2      BackupCursorMaxPos;
+    ImVec1      BackupIndent;
+    ImVec1      BackupGroupOffset;
+    ImVec2      BackupCurrLineSize;
+    float       BackupCurrLineTextBaseOffset;
+    ImGuiID     BackupActiveIdIsAlive;
+    bool        BackupActiveIdPreviousFrameIsAlive;
+    bool        EmitItem;
+};
+
+// Simple column measurement, currently used for MenuItem() only.. This is very short-sighted/throw-away code and NOT a generic helper.
+struct IMGUI_API ImGuiMenuColumns
+{
+    float       Spacing;
+    float       Width, NextWidth;
+    float       Pos[3], NextWidths[3];
+
+    ImGuiMenuColumns();
+    void        Update(int count, float spacing, bool clear);
+    float       DeclColumns(float w0, float w1, float w2);
+    float       CalcExtraSpace(float avail_w) const;
+};
+
+// Internal state of the currently focused/edited text input box
+// For a given item ID, access with ImGui::GetInputTextState()
+struct IMGUI_API ImGuiInputTextState
+{
+    ImGuiID                 ID;                     // widget id owning the text state
+    int                     CurLenW, CurLenA;       // we need to maintain our buffer length in both UTF-8 and wchar format. UTF-8 length is valid even if TextA is not.
+    ImVector<ImWchar>       TextW;                  // edit buffer, we need to persist but can't guarantee the persistence of the user-provided buffer. so we copy into own buffer.
+    ImVector<char>          TextA;                  // temporary UTF8 buffer for callbacks and other operations. this is not updated in every code-path! size=capacity.
+    ImVector<char>          InitialTextA;           // backup of end-user buffer at the time of focus (in UTF-8, unaltered)
+    bool                    TextAIsValid;           // temporary UTF8 buffer is not initially valid before we make the widget active (until then we pull the data from user argument)
+    int                     BufCapacityA;           // end-user buffer capacity
+    float                   ScrollX;                // horizontal scrolling/offset
+    ImStb::STB_TexteditState Stb;                   // state for stb_textedit.h
+    float                   CursorAnim;             // timer for cursor blink, reset on every user action so the cursor reappears immediately
+    bool                    CursorFollow;           // set when we want scrolling to follow the current cursor position (not always!)
+    bool                    SelectedAllMouseLock;   // after a double-click to select all, we ignore further mouse drags to update selection
+    ImGuiInputTextFlags     UserFlags;              // Temporarily set while we call user's callback
+    ImGuiInputTextCallback  UserCallback;           // "
+    void*                   UserCallbackData;       // "
+
+    ImGuiInputTextState()                   { memset(this, 0, sizeof(*this)); }
+    void        ClearText()                 { CurLenW = CurLenA = 0; TextW[0] = 0; TextA[0] = 0; CursorClamp(); }
+    void        ClearFreeMemory()           { TextW.clear(); TextA.clear(); InitialTextA.clear(); }
+    int         GetUndoAvailCount() const   { return Stb.undostate.undo_point; }
+    int         GetRedoAvailCount() const   { return STB_TEXTEDIT_UNDOSTATECOUNT - Stb.undostate.redo_point; }
+    void        OnKeyPressed(int key);      // Cannot be inline because we call in code in stb_textedit.h implementation
+
+    // Cursor & Selection
+    void        CursorAnimReset()           { CursorAnim = -0.30f; }                                   // After a user-input the cursor stays on for a while without blinking
+    void        CursorClamp()               { Stb.cursor = ImMin(Stb.cursor, CurLenW); Stb.select_start = ImMin(Stb.select_start, CurLenW); Stb.select_end = ImMin(Stb.select_end, CurLenW); }
+    bool        HasSelection() const        { return Stb.select_start != Stb.select_end; }
+    void        ClearSelection()            { Stb.select_start = Stb.select_end = Stb.cursor; }
+    void        SelectAll()                 { Stb.select_start = 0; Stb.cursor = Stb.select_end = CurLenW; Stb.has_preferred_x = 0; }
+};
+
+// Windows data saved in imgui.ini file
+// Because we never destroy or rename ImGuiWindowSettings, we can store the names in a separate buffer easily.
+// (this is designed to be stored in a ImChunkStream buffer, with the variable-length Name following our structure)
+struct ImGuiWindowSettings
+{
+    ImGuiID     ID;
+    ImVec2ih    Pos;
+    ImVec2ih    Size;
+    bool        Collapsed;
+
+    ImGuiWindowSettings()       { ID = 0; Pos = Size = ImVec2ih(0, 0); Collapsed = false; }
+    char* GetName()             { return (char*)(this + 1); }
+};
+
+struct ImGuiSettingsHandler
+{
+    const char* TypeName;       // Short description stored in .ini file. Disallowed characters: '[' ']'
+    ImGuiID     TypeHash;       // == ImHashStr(TypeName)
+    void*       (*ReadOpenFn)(ImGuiContext* ctx, ImGuiSettingsHandler* handler, const char* name);              // Read: Called when entering into a new ini entry e.g. "[Window][Name]"
+    void        (*ReadLineFn)(ImGuiContext* ctx, ImGuiSettingsHandler* handler, void* entry, const char* line); // Read: Called for every line of text within an ini entry
+    void        (*WriteAllFn)(ImGuiContext* ctx, ImGuiSettingsHandler* handler, ImGuiTextBuffer* out_buf);      // Write: Output every entries into 'out_buf'
+    void*       UserData;
+
+    ImGuiSettingsHandler() { memset(this, 0, sizeof(*this)); }
+};
+
+// Storage for current popup stack
+struct ImGuiPopupData
+{
+    ImGuiID             PopupId;        // Set on OpenPopup()
+    ImGuiWindow*        Window;         // Resolved on BeginPopup() - may stay unresolved if user never calls OpenPopup()
+    ImGuiWindow*        SourceWindow;   // Set on OpenPopup() copy of NavWindow at the time of opening the popup
+    int                 OpenFrameCount; // Set on OpenPopup()
+    ImGuiID             OpenParentId;   // Set on OpenPopup(), we need this to differentiate multiple menu sets from each others (e.g. inside menu bar vs loose menu items)
+    ImVec2              OpenPopupPos;   // Set on OpenPopup(), preferred popup position (typically == OpenMousePos when using mouse)
+    ImVec2              OpenMousePos;   // Set on OpenPopup(), copy of mouse position at the time of opening popup
+
+    ImGuiPopupData() { PopupId = 0; Window = SourceWindow = NULL; OpenFrameCount = -1; OpenParentId = 0; }
+};
+
+struct ImGuiColumnData
+{
+    float               OffsetNorm;         // Column start offset, normalized 0.0 (far left) -> 1.0 (far right)
+    float               OffsetNormBeforeResize;
+    ImGuiColumnsFlags   Flags;              // Not exposed
+    ImRect              ClipRect;
+
+    ImGuiColumnData()   { OffsetNorm = OffsetNormBeforeResize = 0.0f; Flags = ImGuiColumnsFlags_None; }
+};
+
+struct ImGuiColumns
+{
+    ImGuiID             ID;
+    ImGuiColumnsFlags   Flags;
+    bool                IsFirstFrame;
+    bool                IsBeingResized;
+    int                 Current;
+    int                 Count;
+    float               OffMinX, OffMaxX;       // Offsets from HostWorkRect.Min.x
+    float               LineMinY, LineMaxY;
+    float               HostCursorPosY;         // Backup of CursorPos at the time of BeginColumns()
+    float               HostCursorMaxPosX;      // Backup of CursorMaxPos at the time of BeginColumns()
+    ImRect              HostClipRect;           // Backup of ClipRect at the time of BeginColumns()
+    ImRect              HostWorkRect;           // Backup of WorkRect at the time of BeginColumns()
+    ImVector<ImGuiColumnData> Columns;
+    ImDrawListSplitter  Splitter;
+
+    ImGuiColumns()      { Clear(); }
+    void Clear()
+    {
+        ID = 0;
+        Flags = ImGuiColumnsFlags_None;
+        IsFirstFrame = false;
+        IsBeingResized = false;
+        Current = 0;
+        Count = 1;
+        OffMinX = OffMaxX = 0.0f;
+        LineMinY = LineMaxY = 0.0f;
+        HostCursorPosY = 0.0f;
+        HostCursorMaxPosX = 0.0f;
+        Columns.clear();
+    }
+};
+
+// ImDrawList: Helper function to calculate a circle's segment count given its radius and a "maximum error" value.
+#define IM_DRAWLIST_CIRCLE_AUTO_SEGMENT_MIN                     12
+#define IM_DRAWLIST_CIRCLE_AUTO_SEGMENT_MAX                     512
+#define IM_DRAWLIST_CIRCLE_AUTO_SEGMENT_CALC(_RAD,_MAXERROR)    ImClamp((int)((IM_PI * 2.0f) / ImAcos(((_RAD) - (_MAXERROR)) / (_RAD))), IM_DRAWLIST_CIRCLE_AUTO_SEGMENT_MIN, IM_DRAWLIST_CIRCLE_AUTO_SEGMENT_MAX)
+
+// ImDrawList: You may set this to higher values (e.g. 2 or 3) to increase tessellation of fast rounded corners path.
+#ifndef IM_DRAWLIST_ARCFAST_TESSELLATION_MULTIPLIER
+#define IM_DRAWLIST_ARCFAST_TESSELLATION_MULTIPLIER             1
+#endif
+
+// Data shared between all ImDrawList instances
+// You may want to create your own instance of this if you want to use ImDrawList completely without ImGui. In that case, watch out for future changes to this structure.
+struct IMGUI_API ImDrawListSharedData
+{
+    ImVec2          TexUvWhitePixel;            // UV of white pixel in the atlas
+    ImFont*         Font;                       // Current/default font (optional, for simplified AddText overload)
+    float           FontSize;                   // Current/default font size (optional, for simplified AddText overload)
+    float           CurveTessellationTol;       // Tessellation tolerance when using PathBezierCurveTo()
+    float           CircleSegmentMaxError;      // Number of circle segments to use per pixel of radius for AddCircle() etc
+    ImVec4          ClipRectFullscreen;         // Value for PushClipRectFullscreen()
+    ImDrawListFlags InitialFlags;               // Initial flags at the beginning of the frame (it is possible to alter flags on a per-drawlist basis afterwards)
+
+    // [Internal] Lookup tables
+    ImVec2          ArcFastVtx[12 * IM_DRAWLIST_ARCFAST_TESSELLATION_MULTIPLIER];  // FIXME: Bake rounded corners fill/borders in atlas
+    ImU8            CircleSegmentCounts[64];    // Precomputed segment count for given radius (array index + 1) before we calculate it dynamically (to avoid calculation overhead)
+
+    ImDrawListSharedData();
+    void SetCircleSegmentMaxError(float max_error);
+};
+
+struct ImDrawDataBuilder
+{
+    ImVector<ImDrawList*>   Layers[2];           // Global layers for: regular, tooltip
+
+    void Clear()            { for (int n = 0; n < IM_ARRAYSIZE(Layers); n++) Layers[n].resize(0); }
+    void ClearFreeMemory()  { for (int n = 0; n < IM_ARRAYSIZE(Layers); n++) Layers[n].clear(); }
+    IMGUI_API void FlattenIntoSingleLayer();
+};
+
+struct ImGuiNavMoveResult
+{
+    ImGuiWindow*    Window;             // Best candidate window
+    ImGuiID         ID;                 // Best candidate ID
+    ImGuiID         FocusScopeId;       // Best candidate focus scope ID
+    float           DistBox;            // Best candidate box distance to current NavId
+    float           DistCenter;         // Best candidate center distance to current NavId
+    float           DistAxial;
+    ImRect          RectRel;            // Best candidate bounding box in window relative space
+
+    ImGuiNavMoveResult() { Clear(); }
+    void Clear()         { Window = NULL; ID = FocusScopeId = 0; DistBox = DistCenter = DistAxial = FLT_MAX; RectRel = ImRect(); }
+};
+
+enum ImGuiNextWindowDataFlags_
+{
+    ImGuiNextWindowDataFlags_None               = 0,
+    ImGuiNextWindowDataFlags_HasPos             = 1 << 0,
+    ImGuiNextWindowDataFlags_HasSize            = 1 << 1,
+    ImGuiNextWindowDataFlags_HasContentSize     = 1 << 2,
+    ImGuiNextWindowDataFlags_HasCollapsed       = 1 << 3,
+    ImGuiNextWindowDataFlags_HasSizeConstraint  = 1 << 4,
+    ImGuiNextWindowDataFlags_HasFocus           = 1 << 5,
+    ImGuiNextWindowDataFlags_HasBgAlpha         = 1 << 6,
+    ImGuiNextWindowDataFlags_HasScroll          = 1 << 7
+};
+
+// Storage for SetNexWindow** functions
+struct ImGuiNextWindowData
+{
+    ImGuiNextWindowDataFlags    Flags;
+    ImGuiCond                   PosCond;
+    ImGuiCond                   SizeCond;
+    ImGuiCond                   CollapsedCond;
+    ImVec2                      PosVal;
+    ImVec2                      PosPivotVal;
+    ImVec2                      SizeVal;
+    ImVec2                      ContentSizeVal;
+    ImVec2                      ScrollVal;
+    bool                        CollapsedVal;
+    ImRect                      SizeConstraintRect;
+    ImGuiSizeCallback           SizeCallback;
+    void*                       SizeCallbackUserData;
+    float                       BgAlphaVal;             // Override background alpha
+    ImVec2                      MenuBarOffsetMinVal;    // *Always on* This is not exposed publicly, so we don't clear it.
+
+    ImGuiNextWindowData()       { memset(this, 0, sizeof(*this)); }
+    inline void ClearFlags()    { Flags = ImGuiNextWindowDataFlags_None; }
+};
+
+enum ImGuiNextItemDataFlags_
+{
+    ImGuiNextItemDataFlags_None     = 0,
+    ImGuiNextItemDataFlags_HasWidth = 1 << 0,
+    ImGuiNextItemDataFlags_HasOpen  = 1 << 1
+};
+
+struct ImGuiNextItemData
+{
+    ImGuiNextItemDataFlags      Flags;
+    float                       Width;          // Set by SetNextItemWidth()
+    ImGuiID                     FocusScopeId;   // Set by SetNextItemMultiSelectData() (!= 0 signify value has been set, so it's an alternate version of HasSelectionData, we don't use Flags for this because they are cleared too early. This is mostly used for debugging)
+    ImGuiCond                   OpenCond;
+    bool                        OpenVal;        // Set by SetNextItemOpen()
+
+    ImGuiNextItemData()         { memset(this, 0, sizeof(*this)); }
+    inline void ClearFlags()    { Flags = ImGuiNextItemDataFlags_None; } // Also cleared manually by ItemAdd()!
+};
+
+//-----------------------------------------------------------------------------
+// Tabs
+//-----------------------------------------------------------------------------
+
+struct ImGuiShrinkWidthItem
+{
+    int             Index;
+    float           Width;
+};
+
+struct ImGuiPtrOrIndex
+{
+    void*           Ptr;                // Either field can be set, not both. e.g. Dock node tab bars are loose while BeginTabBar() ones are in a pool.
+    int             Index;              // Usually index in a main pool.
+
+    ImGuiPtrOrIndex(void* ptr)          { Ptr = ptr; Index = -1; }
+    ImGuiPtrOrIndex(int index)          { Ptr = NULL; Index = index; }
+};
+
+//-----------------------------------------------------------------------------
+// Main Dear ImGui context
+//-----------------------------------------------------------------------------
+
+struct ImGuiContext
+{
+    bool                    Initialized;
+    bool                    FontAtlasOwnedByContext;            // IO.Fonts-> is owned by the ImGuiContext and will be destructed along with it.
+    ImGuiIO                 IO;
+    ImGuiStyle              Style;
+    ImFont*                 Font;                               // (Shortcut) == FontStack.empty() ? IO.Font : FontStack.back()
+    float                   FontSize;                           // (Shortcut) == FontBaseSize * g.CurrentWindow->FontWindowScale == window->FontSize(). Text height for current window.
+    float                   FontBaseSize;                       // (Shortcut) == IO.FontGlobalScale * Font->Scale * Font->FontSize. Base text height.
+    ImDrawListSharedData    DrawListSharedData;
+    double                  Time;
+    int                     FrameCount;
+    int                     FrameCountEnded;
+    int                     FrameCountRendered;
+    bool                    WithinFrameScope;                   // Set by NewFrame(), cleared by EndFrame()
+    bool                    WithinFrameScopeWithImplicitWindow; // Set by NewFrame(), cleared by EndFrame() when the implicit debug window has been pushed
+    bool                    WithinEndChild;                     // Set within EndChild()
+    bool                    TestEngineHookItems;                // Will call test engine hooks: ImGuiTestEngineHook_ItemAdd(), ImGuiTestEngineHook_ItemInfo(), ImGuiTestEngineHook_Log()
+    ImGuiID                 TestEngineHookIdInfo;               // Will call test engine hooks: ImGuiTestEngineHook_IdInfo() from GetID()
+    void*                   TestEngine;                         // Test engine user data
+
+    // Windows state
+    ImVector<ImGuiWindow*>  Windows;                            // Windows, sorted in display order, back to front
+    ImVector<ImGuiWindow*>  WindowsFocusOrder;                  // Windows, sorted in focus order, back to front. (FIXME: We could only store root windows here! Need to sort out the Docking equivalent which is RootWindowDockStop and is unfortunately a little more dynamic)
+    ImVector<ImGuiWindow*>  WindowsTempSortBuffer;              // Temporary buffer used in EndFrame() to reorder windows so parents are kept before their child
+    ImVector<ImGuiWindow*>  CurrentWindowStack;
+    ImGuiStorage            WindowsById;                        // Map window's ImGuiID to ImGuiWindow*
+    int                     WindowsActiveCount;                 // Number of unique windows submitted by frame
+    ImGuiWindow*            CurrentWindow;                      // Window being drawn into
+    ImGuiWindow*            HoveredWindow;                      // Will catch mouse inputs
+    ImGuiWindow*            HoveredRootWindow;                  // Will catch mouse inputs (for focus/move only)
+    ImGuiWindow*            MovingWindow;                       // Track the window we clicked on (in order to preserve focus). The actually window that is moved is generally MovingWindow->RootWindow.
+    ImGuiWindow*            WheelingWindow;                     // Track the window we started mouse-wheeling on. Until a timer elapse or mouse has moved, generally keep scrolling the same window even if during the course of scrolling the mouse ends up hovering a child window.
+    ImVec2                  WheelingWindowRefMousePos;
+    float                   WheelingWindowTimer;
+
+    // Item/widgets state and tracking information
+    ImGuiID                 HoveredId;                          // Hovered widget
+    bool                    HoveredIdAllowOverlap;
+    ImGuiID                 HoveredIdPreviousFrame;
+    float                   HoveredIdTimer;                     // Measure contiguous hovering time
+    float                   HoveredIdNotActiveTimer;            // Measure contiguous hovering time where the item has not been active
+    ImGuiID                 ActiveId;                           // Active widget
+    ImGuiID                 ActiveIdIsAlive;                    // Active widget has been seen this frame (we can't use a bool as the ActiveId may change within the frame)
+    float                   ActiveIdTimer;
+    bool                    ActiveIdIsJustActivated;            // Set at the time of activation for one frame
+    bool                    ActiveIdAllowOverlap;               // Active widget allows another widget to steal active id (generally for overlapping widgets, but not always)
+    bool                    ActiveIdHasBeenPressedBefore;       // Track whether the active id led to a press (this is to allow changing between PressOnClick and PressOnRelease without pressing twice). Used by range_select branch.
+    bool                    ActiveIdHasBeenEditedBefore;        // Was the value associated to the widget Edited over the course of the Active state.
+    bool                    ActiveIdHasBeenEditedThisFrame;
+    ImU32                   ActiveIdUsingNavDirMask;            // Active widget will want to read those nav move requests (e.g. can activate a button and move away from it)
+    ImU32                   ActiveIdUsingNavInputMask;          // Active widget will want to read those nav inputs.
+    ImU64                   ActiveIdUsingKeyInputMask;          // Active widget will want to read those key inputs. When we grow the ImGuiKey enum we'll need to either to order the enum to make useful keys come first, either redesign this into e.g. a small array.
+    ImVec2                  ActiveIdClickOffset;                // Clicked offset from upper-left corner, if applicable (currently only set by ButtonBehavior)
+    ImGuiWindow*            ActiveIdWindow;
+    ImGuiInputSource        ActiveIdSource;                     // Activating with mouse or nav (gamepad/keyboard)
+    int                     ActiveIdMouseButton;
+    ImGuiID                 ActiveIdPreviousFrame;
+    bool                    ActiveIdPreviousFrameIsAlive;
+    bool                    ActiveIdPreviousFrameHasBeenEditedBefore;
+    ImGuiWindow*            ActiveIdPreviousFrameWindow;
+    ImGuiID                 LastActiveId;                       // Store the last non-zero ActiveId, useful for animation.
+    float                   LastActiveIdTimer;                  // Store the last non-zero ActiveId timer since the beginning of activation, useful for animation.
+
+    // Next window/item data
+    ImGuiNextWindowData     NextWindowData;                     // Storage for SetNextWindow** functions
+    ImGuiNextItemData       NextItemData;                       // Storage for SetNextItem** functions
+
+    // Shared stacks
+    ImVector<ImGuiColorMod> ColorModifiers;                     // Stack for PushStyleColor()/PopStyleColor()
+    ImVector<ImGuiStyleMod> StyleModifiers;                     // Stack for PushStyleVar()/PopStyleVar()
+    ImVector<ImFont*>       FontStack;                          // Stack for PushFont()/PopFont()
+    ImVector<ImGuiPopupData>OpenPopupStack;                     // Which popups are open (persistent)
+    ImVector<ImGuiPopupData>BeginPopupStack;                    // Which level of BeginPopup() we are in (reset every frame)
+
+    // Gamepad/keyboard Navigation
+    ImGuiWindow*            NavWindow;                          // Focused window for navigation. Could be called 'FocusWindow'
+    ImGuiID                 NavId;                              // Focused item for navigation
+    ImGuiID                 NavFocusScopeId;
+    ImGuiID                 NavActivateId;                      // ~~ (g.ActiveId == 0) && IsNavInputPressed(ImGuiNavInput_Activate) ? NavId : 0, also set when calling ActivateItem()
+    ImGuiID                 NavActivateDownId;                  // ~~ IsNavInputDown(ImGuiNavInput_Activate) ? NavId : 0
+    ImGuiID                 NavActivatePressedId;               // ~~ IsNavInputPressed(ImGuiNavInput_Activate) ? NavId : 0
+    ImGuiID                 NavInputId;                         // ~~ IsNavInputPressed(ImGuiNavInput_Input) ? NavId : 0
+    ImGuiID                 NavJustTabbedId;                    // Just tabbed to this id.
+    ImGuiID                 NavJustMovedToId;                   // Just navigated to this id (result of a successfully MoveRequest).
+    ImGuiID                 NavJustMovedToFocusScopeId;         // Just navigated to this focus scope id (result of a successfully MoveRequest).
+    ImGuiKeyModFlags        NavJustMovedToKeyMods;
+    ImGuiID                 NavNextActivateId;                  // Set by ActivateItem(), queued until next frame.
+    ImGuiInputSource        NavInputSource;                     // Keyboard or Gamepad mode? THIS WILL ONLY BE None or NavGamepad or NavKeyboard.
+    ImRect                  NavScoringRect;                     // Rectangle used for scoring, in screen space. Based of window->DC.NavRefRectRel[], modified for directional navigation scoring.
+    int                     NavScoringCount;                    // Metrics for debugging
+    ImGuiNavLayer           NavLayer;                           // Layer we are navigating on. For now the system is hard-coded for 0=main contents and 1=menu/title bar, may expose layers later.
+    int                     NavIdTabCounter;                    // == NavWindow->DC.FocusIdxTabCounter at time of NavId processing
+    bool                    NavIdIsAlive;                       // Nav widget has been seen this frame ~~ NavRefRectRel is valid
+    bool                    NavMousePosDirty;                   // When set we will update mouse position if (io.ConfigFlags & ImGuiConfigFlags_NavEnableSetMousePos) if set (NB: this not enabled by default)
+    bool                    NavDisableHighlight;                // When user starts using mouse, we hide gamepad/keyboard highlight (NB: but they are still available, which is why NavDisableHighlight isn't always != NavDisableMouseHover)
+    bool                    NavDisableMouseHover;               // When user starts using gamepad/keyboard, we hide mouse hovering highlight until mouse is touched again.
+    bool                    NavAnyRequest;                      // ~~ NavMoveRequest || NavInitRequest
+    bool                    NavInitRequest;                     // Init request for appearing window to select first item
+    bool                    NavInitRequestFromMove;
+    ImGuiID                 NavInitResultId;
+    ImRect                  NavInitResultRectRel;
+    bool                    NavMoveFromClampedRefRect;          // Set by manual scrolling, if we scroll to a point where NavId isn't visible we reset navigation from visible items
+    bool                    NavMoveRequest;                     // Move request for this frame
+    ImGuiNavMoveFlags       NavMoveRequestFlags;
+    ImGuiNavForward         NavMoveRequestForward;              // None / ForwardQueued / ForwardActive (this is used to navigate sibling parent menus from a child menu)
+    ImGuiKeyModFlags        NavMoveRequestKeyMods;
+    ImGuiDir                NavMoveDir, NavMoveDirLast;         // Direction of the move request (left/right/up/down), direction of the previous move request
+    ImGuiDir                NavMoveClipDir;                     // FIXME-NAV: Describe the purpose of this better. Might want to rename?
+    ImGuiNavMoveResult      NavMoveResultLocal;                 // Best move request candidate within NavWindow
+    ImGuiNavMoveResult      NavMoveResultLocalVisibleSet;       // Best move request candidate within NavWindow that are mostly visible (when using ImGuiNavMoveFlags_AlsoScoreVisibleSet flag)
+    ImGuiNavMoveResult      NavMoveResultOther;                 // Best move request candidate within NavWindow's flattened hierarchy (when using ImGuiWindowFlags_NavFlattened flag)
+
+    // Navigation: Windowing (CTRL+TAB, holding Menu button + directional pads to move/resize)
+    ImGuiWindow*            NavWindowingTarget;                 // When selecting a window (holding Menu+FocusPrev/Next, or equivalent of CTRL-TAB) this window is temporarily displayed top-most.
+    ImGuiWindow*            NavWindowingTargetAnim;             // Record of last valid NavWindowingTarget until DimBgRatio and NavWindowingHighlightAlpha becomes 0.0f
+    ImGuiWindow*            NavWindowingList;
+    float                   NavWindowingTimer;
+    float                   NavWindowingHighlightAlpha;
+    bool                    NavWindowingToggleLayer;
+
+    // Legacy Focus/Tabbing system (older than Nav, active even if Nav is disabled, misnamed. FIXME-NAV: This needs a redesign!)
+    ImGuiWindow*            FocusRequestCurrWindow;             //
+    ImGuiWindow*            FocusRequestNextWindow;             //
+    int                     FocusRequestCurrCounterRegular;     // Any item being requested for focus, stored as an index (we on layout to be stable between the frame pressing TAB and the next frame, semi-ouch)
+    int                     FocusRequestCurrCounterTabStop;     // Tab item being requested for focus, stored as an index
+    int                     FocusRequestNextCounterRegular;     // Stored for next frame
+    int                     FocusRequestNextCounterTabStop;     // "
+    bool                    FocusTabPressed;                    //
+
+    // Render
+    ImDrawData              DrawData;                           // Main ImDrawData instance to pass render information to the user
+    ImDrawDataBuilder       DrawDataBuilder;
+    float                   DimBgRatio;                         // 0.0..1.0 animation when fading in a dimming background (for modal window and CTRL+TAB list)
+    ImDrawList              BackgroundDrawList;                 // First draw list to be rendered.
+    ImDrawList              ForegroundDrawList;                 // Last draw list to be rendered. This is where we the render software mouse cursor (if io.MouseDrawCursor is set) and most debug overlays.
+    ImGuiMouseCursor        MouseCursor;
+
+    // Drag and Drop
+    bool                    DragDropActive;
+    bool                    DragDropWithinSource;               // Set when within a BeginDragDropXXX/EndDragDropXXX block for a drag source.
+    bool                    DragDropWithinTarget;               // Set when within a BeginDragDropXXX/EndDragDropXXX block for a drag target.
+    ImGuiDragDropFlags      DragDropSourceFlags;
+    int                     DragDropSourceFrameCount;
+    int                     DragDropMouseButton;
+    ImGuiPayload            DragDropPayload;
+    ImRect                  DragDropTargetRect;                 // Store rectangle of current target candidate (we favor small targets when overlapping)
+    ImGuiID                 DragDropTargetId;
+    ImGuiDragDropFlags      DragDropAcceptFlags;
+    float                   DragDropAcceptIdCurrRectSurface;    // Target item surface (we resolve overlapping targets by prioritizing the smaller surface)
+    ImGuiID                 DragDropAcceptIdCurr;               // Target item id (set at the time of accepting the payload)
+    ImGuiID                 DragDropAcceptIdPrev;               // Target item id from previous frame (we need to store this to allow for overlapping drag and drop targets)
+    int                     DragDropAcceptFrameCount;           // Last time a target expressed a desire to accept the source
+    ImGuiID                 DragDropHoldJustPressedId;          // Set when holding a payload just made ButtonBehavior() return a press.
+    ImVector<unsigned char> DragDropPayloadBufHeap;             // We don't expose the ImVector<> directly, ImGuiPayload only holds pointer+size
+    unsigned char           DragDropPayloadBufLocal[16];        // Local buffer for small payloads
+
+    // Tab bars
+    ImGuiTabBar*                    CurrentTabBar;
+    ImPool<ImGuiTabBar>             TabBars;
+    ImVector<ImGuiPtrOrIndex>       CurrentTabBarStack;
+    ImVector<ImGuiShrinkWidthItem>  ShrinkWidthBuffer;
+
+    // Widget state
+    ImVec2                  LastValidMousePos;
+    ImGuiInputTextState     InputTextState;
+    ImFont                  InputTextPasswordFont;
+    ImGuiID                 TempInputId;                        // Temporary text input when CTRL+clicking on a slider, etc.
+    ImGuiColorEditFlags     ColorEditOptions;                   // Store user options for color edit widgets
+    float                   ColorEditLastHue;                   // Backup of last Hue associated to LastColor[3], so we can restore Hue in lossy RGB<>HSV round trips
+    float                   ColorEditLastSat;                   // Backup of last Saturation associated to LastColor[3], so we can restore Saturation in lossy RGB<>HSV round trips
+    float                   ColorEditLastColor[3];
+    ImVec4                  ColorPickerRef;                     // Initial/reference color at the time of opening the color picker.
+    bool                    DragCurrentAccumDirty;
+    float                   DragCurrentAccum;                   // Accumulator for dragging modification. Always high-precision, not rounded by end-user precision settings
+    float                   DragSpeedDefaultRatio;              // If speed == 0.0f, uses (max-min) * DragSpeedDefaultRatio
+    float                   ScrollbarClickDeltaToGrabCenter;    // Distance between mouse and center of grab box, normalized in parent space. Use storage?
+    int                     TooltipOverrideCount;
+    ImVector<char>          ClipboardHandlerData;               // If no custom clipboard handler is defined
+    ImVector<ImGuiID>       MenusIdSubmittedThisFrame;          // A list of menu IDs that were rendered at least once
+
+    // Platform support
+    ImVec2                  PlatformImePos;                     // Cursor position request & last passed to the OS Input Method Editor
+    ImVec2                  PlatformImeLastPos;
+
+    // Settings
+    bool                    SettingsLoaded;
+    float                   SettingsDirtyTimer;                 // Save .ini Settings to memory when time reaches zero
+    ImGuiTextBuffer         SettingsIniData;                    // In memory .ini settings
+    ImVector<ImGuiSettingsHandler>      SettingsHandlers;       // List of .ini settings handlers
+    ImChunkStream<ImGuiWindowSettings>  SettingsWindows;        // ImGuiWindow .ini settings entries
+
+    // Capture/Logging
+    bool                    LogEnabled;
+    ImGuiLogType            LogType;
+    ImFileHandle            LogFile;                            // If != NULL log to stdout/ file
+    ImGuiTextBuffer         LogBuffer;                          // Accumulation buffer when log to clipboard. This is pointer so our GImGui static constructor doesn't call heap allocators.
+    float                   LogLinePosY;
+    bool                    LogLineFirstItem;
+    int                     LogDepthRef;
+    int                     LogDepthToExpand;
+    int                     LogDepthToExpandDefault;            // Default/stored value for LogDepthMaxExpand if not specified in the LogXXX function call.
+
+    // Debug Tools
+    bool                    DebugItemPickerActive;
+    ImGuiID                 DebugItemPickerBreakId;             // Will call IM_DEBUG_BREAK() when encountering this id
+
+    // Misc
+    float                   FramerateSecPerFrame[120];          // Calculate estimate of framerate for user over the last 2 seconds.
+    int                     FramerateSecPerFrameIdx;
+    float                   FramerateSecPerFrameAccum;
+    int                     WantCaptureMouseNextFrame;          // Explicit capture via CaptureKeyboardFromApp()/CaptureMouseFromApp() sets those flags
+    int                     WantCaptureKeyboardNextFrame;
+    int                     WantTextInputNextFrame;
+    char                    TempBuffer[1024*3+1];               // Temporary text buffer
+
+    ImGuiContext(ImFontAtlas* shared_font_atlas) : BackgroundDrawList(&DrawListSharedData), ForegroundDrawList(&DrawListSharedData)
+    {
+        Initialized = false;
+        FontAtlasOwnedByContext = shared_font_atlas ? false : true;
+        Font = NULL;
+        FontSize = FontBaseSize = 0.0f;
+        IO.Fonts = shared_font_atlas ? shared_font_atlas : IM_NEW(ImFontAtlas)();
+        Time = 0.0f;
+        FrameCount = 0;
+        FrameCountEnded = FrameCountRendered = -1;
+        WithinFrameScope = WithinFrameScopeWithImplicitWindow = WithinEndChild = false;
+        TestEngineHookItems = false;
+        TestEngineHookIdInfo = 0;
+        TestEngine = NULL;
+
+        WindowsActiveCount = 0;
+        CurrentWindow = NULL;
+        HoveredWindow = NULL;
+        HoveredRootWindow = NULL;
+        MovingWindow = NULL;
+        WheelingWindow = NULL;
+        WheelingWindowTimer = 0.0f;
+
+        HoveredId = 0;
+        HoveredIdAllowOverlap = false;
+        HoveredIdPreviousFrame = 0;
+        HoveredIdTimer = HoveredIdNotActiveTimer = 0.0f;
+        ActiveId = 0;
+        ActiveIdIsAlive = 0;
+        ActiveIdTimer = 0.0f;
+        ActiveIdIsJustActivated = false;
+        ActiveIdAllowOverlap = false;
+        ActiveIdHasBeenPressedBefore = false;
+        ActiveIdHasBeenEditedBefore = false;
+        ActiveIdHasBeenEditedThisFrame = false;
+        ActiveIdUsingNavDirMask = 0x00;
+        ActiveIdUsingNavInputMask = 0x00;
+        ActiveIdUsingKeyInputMask = 0x00;
+        ActiveIdClickOffset = ImVec2(-1,-1);
+        ActiveIdWindow = NULL;
+        ActiveIdSource = ImGuiInputSource_None;
+        ActiveIdMouseButton = 0;
+        ActiveIdPreviousFrame = 0;
+        ActiveIdPreviousFrameIsAlive = false;
+        ActiveIdPreviousFrameHasBeenEditedBefore = false;
+        ActiveIdPreviousFrameWindow = NULL;
+        LastActiveId = 0;
+        LastActiveIdTimer = 0.0f;
+
+        NavWindow = NULL;
+        NavId = NavFocusScopeId = NavActivateId = NavActivateDownId = NavActivatePressedId = NavInputId = 0;
+        NavJustTabbedId = NavJustMovedToId = NavJustMovedToFocusScopeId = NavNextActivateId = 0;
+        NavJustMovedToKeyMods = ImGuiKeyModFlags_None;
+        NavInputSource = ImGuiInputSource_None;
+        NavScoringRect = ImRect();
+        NavScoringCount = 0;
+        NavLayer = ImGuiNavLayer_Main;
+        NavIdTabCounter = INT_MAX;
+        NavIdIsAlive = false;
+        NavMousePosDirty = false;
+        NavDisableHighlight = true;
+        NavDisableMouseHover = false;
+        NavAnyRequest = false;
+        NavInitRequest = false;
+        NavInitRequestFromMove = false;
+        NavInitResultId = 0;
+        NavMoveFromClampedRefRect = false;
+        NavMoveRequest = false;
+        NavMoveRequestFlags = ImGuiNavMoveFlags_None;
+        NavMoveRequestForward = ImGuiNavForward_None;
+        NavMoveRequestKeyMods = ImGuiKeyModFlags_None;
+        NavMoveDir = NavMoveDirLast = NavMoveClipDir = ImGuiDir_None;
+
+        NavWindowingTarget = NavWindowingTargetAnim = NavWindowingList = NULL;
+        NavWindowingTimer = NavWindowingHighlightAlpha = 0.0f;
+        NavWindowingToggleLayer = false;
+
+        FocusRequestCurrWindow = FocusRequestNextWindow = NULL;
+        FocusRequestCurrCounterRegular = FocusRequestCurrCounterTabStop = INT_MAX;
+        FocusRequestNextCounterRegular = FocusRequestNextCounterTabStop = INT_MAX;
+        FocusTabPressed = false;
+
+        DimBgRatio = 0.0f;
+        BackgroundDrawList._OwnerName = "##Background"; // Give it a name for debugging
+        ForegroundDrawList._OwnerName = "##Foreground"; // Give it a name for debugging
+        MouseCursor = ImGuiMouseCursor_Arrow;
+
+        DragDropActive = DragDropWithinSource = DragDropWithinTarget = false;
+        DragDropSourceFlags = ImGuiDragDropFlags_None;
+        DragDropSourceFrameCount = -1;
+        DragDropMouseButton = -1;
+        DragDropTargetId = 0;
+        DragDropAcceptFlags = ImGuiDragDropFlags_None;
+        DragDropAcceptIdCurrRectSurface = 0.0f;
+        DragDropAcceptIdPrev = DragDropAcceptIdCurr = 0;
+        DragDropAcceptFrameCount = -1;
+        DragDropHoldJustPressedId = 0;
+        memset(DragDropPayloadBufLocal, 0, sizeof(DragDropPayloadBufLocal));
+
+        CurrentTabBar = NULL;
+
+        LastValidMousePos = ImVec2(0.0f, 0.0f);
+        TempInputId = 0;
+        ColorEditOptions = ImGuiColorEditFlags__OptionsDefault;
+        ColorEditLastHue = ColorEditLastSat = 0.0f;
+        ColorEditLastColor[0] = ColorEditLastColor[1] = ColorEditLastColor[2] = FLT_MAX;
+        DragCurrentAccumDirty = false;
+        DragCurrentAccum = 0.0f;
+        DragSpeedDefaultRatio = 1.0f / 100.0f;
+        ScrollbarClickDeltaToGrabCenter = 0.0f;
+        TooltipOverrideCount = 0;
+
+        PlatformImePos = PlatformImeLastPos = ImVec2(FLT_MAX, FLT_MAX);
+
+        SettingsLoaded = false;
+        SettingsDirtyTimer = 0.0f;
+
+        LogEnabled = false;
+        LogType = ImGuiLogType_None;
+        LogFile = NULL;
+        LogLinePosY = FLT_MAX;
+        LogLineFirstItem = false;
+        LogDepthRef = 0;
+        LogDepthToExpand = LogDepthToExpandDefault = 2;
+
+        DebugItemPickerActive = false;
+        DebugItemPickerBreakId = 0;
+
+        memset(FramerateSecPerFrame, 0, sizeof(FramerateSecPerFrame));
+        FramerateSecPerFrameIdx = 0;
+        FramerateSecPerFrameAccum = 0.0f;
+        WantCaptureMouseNextFrame = WantCaptureKeyboardNextFrame = WantTextInputNextFrame = -1;
+        memset(TempBuffer, 0, sizeof(TempBuffer));
+    }
+};
+
+//-----------------------------------------------------------------------------
+// ImGuiWindow
+//-----------------------------------------------------------------------------
+
+// Transient per-window data, reset at the beginning of the frame. This used to be called ImGuiDrawContext, hence the DC variable name in ImGuiWindow.
+// FIXME: That's theory, in practice the delimitation between ImGuiWindow and ImGuiWindowTempData is quite tenuous and could be reconsidered.
+struct IMGUI_API ImGuiWindowTempData
+{
+    // Layout
+    ImVec2                  CursorPos;              // Current emitting position, in absolute coordinates.
+    ImVec2                  CursorPosPrevLine;
+    ImVec2                  CursorStartPos;         // Initial position after Begin(), generally ~ window position + WindowPadding.
+    ImVec2                  CursorMaxPos;           // Used to implicitly calculate the size of our contents, always growing during the frame. Used to calculate window->ContentSize at the beginning of next frame
+    ImVec2                  CurrLineSize;
+    ImVec2                  PrevLineSize;
+    float                   CurrLineTextBaseOffset; // Baseline offset (0.0f by default on a new line, generally == style.FramePadding.y when a framed item has been added).
+    float                   PrevLineTextBaseOffset;
+    ImVec1                  Indent;                 // Indentation / start position from left of window (increased by TreePush/TreePop, etc.)
+    ImVec1                  ColumnsOffset;          // Offset to the current column (if ColumnsCurrent > 0). FIXME: This and the above should be a stack to allow use cases like Tree->Column->Tree. Need revamp columns API.
+    ImVec1                  GroupOffset;
+
+    // Last item status
+    ImGuiID                 LastItemId;             // ID for last item
+    ImGuiItemStatusFlags    LastItemStatusFlags;    // Status flags for last item (see ImGuiItemStatusFlags_)
+    ImRect                  LastItemRect;           // Interaction rect for last item
+    ImRect                  LastItemDisplayRect;    // End-user display rect for last item (only valid if LastItemStatusFlags & ImGuiItemStatusFlags_HasDisplayRect)
+
+    // Keyboard/Gamepad navigation
+    ImGuiNavLayer           NavLayerCurrent;        // Current layer, 0..31 (we currently only use 0..1)
+    int                     NavLayerCurrentMask;    // = (1 << NavLayerCurrent) used by ItemAdd prior to clipping.
+    int                     NavLayerActiveMask;     // Which layer have been written to (result from previous frame)
+    int                     NavLayerActiveMaskNext; // Which layer have been written to (buffer for current frame)
+    ImGuiID                 NavFocusScopeIdCurrent; // Current focus scope ID while appending
+    bool                    NavHideHighlightOneFrame;
+    bool                    NavHasScroll;           // Set when scrolling can be used (ScrollMax > 0.0f)
+
+    // Miscellaneous
+    bool                    MenuBarAppending;       // FIXME: Remove this
+    ImVec2                  MenuBarOffset;          // MenuBarOffset.x is sort of equivalent of a per-layer CursorPos.x, saved/restored as we switch to the menu bar. The only situation when MenuBarOffset.y is > 0 if when (SafeAreaPadding.y > FramePadding.y), often used on TVs.
+    ImGuiMenuColumns        MenuColumns;            // Simplified columns storage for menu items measurement
+    int                     TreeDepth;              // Current tree depth.
+    ImU32                   TreeJumpToParentOnPopMask; // Store a copy of !g.NavIdIsAlive for TreeDepth 0..31.. Could be turned into a ImU64 if necessary.
+    ImVector<ImGuiWindow*>  ChildWindows;
+    ImGuiStorage*           StateStorage;           // Current persistent per-window storage (store e.g. tree node open/close state)
+    ImGuiColumns*           CurrentColumns;         // Current columns set
+    ImGuiLayoutType         LayoutType;
+    ImGuiLayoutType         ParentLayoutType;       // Layout type of parent window at the time of Begin()
+    int                     FocusCounterRegular;    // (Legacy Focus/Tabbing system) Sequential counter, start at -1 and increase as assigned via FocusableItemRegister() (FIXME-NAV: Needs redesign)
+    int                     FocusCounterTabStop;    // (Legacy Focus/Tabbing system) Same, but only count widgets which you can Tab through.
+
+    // Local parameters stacks
+    // We store the current settings outside of the vectors to increase memory locality (reduce cache misses). The vectors are rarely modified. Also it allows us to not heap allocate for short-lived windows which are not using those settings.
+    ImGuiItemFlags          ItemFlags;              // == ItemFlagsStack.back() [empty == ImGuiItemFlags_Default]
+    float                   ItemWidth;              // == ItemWidthStack.back(). 0.0: default, >0.0: width in pixels, <0.0: align xx pixels to the right of window
+    float                   TextWrapPos;            // == TextWrapPosStack.back() [empty == -1.0f]
+    ImVector<ImGuiItemFlags>ItemFlagsStack;
+    ImVector<float>         ItemWidthStack;
+    ImVector<float>         TextWrapPosStack;
+    ImVector<ImGuiGroupData>GroupStack;
+    short                   StackSizesBackup[6];    // Store size of various stacks for asserting
+
+    ImGuiWindowTempData()
+    {
+        CursorPos = CursorPosPrevLine = CursorStartPos = CursorMaxPos = ImVec2(0.0f, 0.0f);
+        CurrLineSize = PrevLineSize = ImVec2(0.0f, 0.0f);
+        CurrLineTextBaseOffset = PrevLineTextBaseOffset = 0.0f;
+        Indent = ImVec1(0.0f);
+        ColumnsOffset = ImVec1(0.0f);
+        GroupOffset = ImVec1(0.0f);
+
+        LastItemId = 0;
+        LastItemStatusFlags = ImGuiItemStatusFlags_None;
+        LastItemRect = LastItemDisplayRect = ImRect();
+
+        NavLayerActiveMask = NavLayerActiveMaskNext = 0x00;
+        NavLayerCurrent = ImGuiNavLayer_Main;
+        NavLayerCurrentMask = (1 << ImGuiNavLayer_Main);
+        NavFocusScopeIdCurrent = 0;
+        NavHideHighlightOneFrame = false;
+        NavHasScroll = false;
+
+        MenuBarAppending = false;
+        MenuBarOffset = ImVec2(0.0f, 0.0f);
+        TreeDepth = 0;
+        TreeJumpToParentOnPopMask = 0x00;
+        StateStorage = NULL;
+        CurrentColumns = NULL;
+        LayoutType = ParentLayoutType = ImGuiLayoutType_Vertical;
+        FocusCounterRegular = FocusCounterTabStop = -1;
+
+        ItemFlags = ImGuiItemFlags_Default_;
+        ItemWidth = 0.0f;
+        TextWrapPos = -1.0f;
+        memset(StackSizesBackup, 0, sizeof(StackSizesBackup));
+    }
+};
+
+// Storage for one window
+struct IMGUI_API ImGuiWindow
+{
+    char*                   Name;                               // Window name, owned by the window.
+    ImGuiID                 ID;                                 // == ImHashStr(Name)
+    ImGuiWindowFlags        Flags;                              // See enum ImGuiWindowFlags_
+    ImVec2                  Pos;                                // Position (always rounded-up to nearest pixel)
+    ImVec2                  Size;                               // Current size (==SizeFull or collapsed title bar size)
+    ImVec2                  SizeFull;                           // Size when non collapsed
+    ImVec2                  ContentSize;                        // Size of contents/scrollable client area (calculated from the extents reach of the cursor) from previous frame. Does not include window decoration or window padding.
+    ImVec2                  ContentSizeExplicit;                // Size of contents/scrollable client area explicitly request by the user via SetNextWindowContentSize().
+    ImVec2                  WindowPadding;                      // Window padding at the time of Begin().
+    float                   WindowRounding;                     // Window rounding at the time of Begin().
+    float                   WindowBorderSize;                   // Window border size at the time of Begin().
+    int                     NameBufLen;                         // Size of buffer storing Name. May be larger than strlen(Name)!
+    ImGuiID                 MoveId;                             // == window->GetID("#MOVE")
+    ImGuiID                 ChildId;                            // ID of corresponding item in parent window (for navigation to return from child window to parent window)
+    ImVec2                  Scroll;
+    ImVec2                  ScrollMax;
+    ImVec2                  ScrollTarget;                       // target scroll position. stored as cursor position with scrolling canceled out, so the highest point is always 0.0f. (FLT_MAX for no change)
+    ImVec2                  ScrollTargetCenterRatio;            // 0.0f = scroll so that target position is at top, 0.5f = scroll so that target position is centered
+    ImVec2                  ScrollbarSizes;                     // Size taken by each scrollbars on their smaller axis. Pay attention! ScrollbarSizes.x == width of the vertical scrollbar, ScrollbarSizes.y = height of the horizontal scrollbar.
+    bool                    ScrollbarX, ScrollbarY;             // Are scrollbars visible?
+    bool                    Active;                             // Set to true on Begin(), unless Collapsed
+    bool                    WasActive;
+    bool                    WriteAccessed;                      // Set to true when any widget access the current window
+    bool                    Collapsed;                          // Set when collapsing window to become only title-bar
+    bool                    WantCollapseToggle;
+    bool                    SkipItems;                          // Set when items can safely be all clipped (e.g. window not visible or collapsed)
+    bool                    Appearing;                          // Set during the frame where the window is appearing (or re-appearing)
+    bool                    Hidden;                             // Do not display (== (HiddenFrames*** > 0))
+    bool                    IsFallbackWindow;                   // Set on the "Debug##Default" window.
+    bool                    HasCloseButton;                     // Set when the window has a close button (p_open != NULL)
+    signed char             ResizeBorderHeld;                   // Current border being held for resize (-1: none, otherwise 0-3)
+    short                   BeginCount;                         // Number of Begin() during the current frame (generally 0 or 1, 1+ if appending via multiple Begin/End pairs)
+    short                   BeginOrderWithinParent;             // Order within immediate parent window, if we are a child window. Otherwise 0.
+    short                   BeginOrderWithinContext;            // Order within entire imgui context. This is mostly used for debugging submission order related issues.
+    ImGuiID                 PopupId;                            // ID in the popup stack when this window is used as a popup/menu (because we use generic Name/ID for recycling)
+    ImS8                    AutoFitFramesX, AutoFitFramesY;
+    ImS8                    AutoFitChildAxises;
+    bool                    AutoFitOnlyGrows;
+    ImGuiDir                AutoPosLastDirection;
+    int                     HiddenFramesCanSkipItems;           // Hide the window for N frames
+    int                     HiddenFramesCannotSkipItems;        // Hide the window for N frames while allowing items to be submitted so we can measure their size
+    ImGuiCond               SetWindowPosAllowFlags;             // store acceptable condition flags for SetNextWindowPos() use.
+    ImGuiCond               SetWindowSizeAllowFlags;            // store acceptable condition flags for SetNextWindowSize() use.
+    ImGuiCond               SetWindowCollapsedAllowFlags;       // store acceptable condition flags for SetNextWindowCollapsed() use.
+    ImVec2                  SetWindowPosVal;                    // store window position when using a non-zero Pivot (position set needs to be processed when we know the window size)
+    ImVec2                  SetWindowPosPivot;                  // store window pivot for positioning. ImVec2(0,0) when positioning from top-left corner; ImVec2(0.5f,0.5f) for centering; ImVec2(1,1) for bottom right.
+
+    ImVector<ImGuiID>       IDStack;                            // ID stack. ID are hashes seeded with the value at the top of the stack. (In theory this should be in the TempData structure)
+    ImGuiWindowTempData     DC;                                 // Temporary per-window data, reset at the beginning of the frame. This used to be called ImGuiDrawContext, hence the "DC" variable name.
+
+    // The best way to understand what those rectangles are is to use the 'Metrics -> Tools -> Show windows rectangles' viewer.
+    // The main 'OuterRect', omitted as a field, is window->Rect().
+    ImRect                  OuterRectClipped;                   // == Window->Rect() just after setup in Begin(). == window->Rect() for root window.
+    ImRect                  InnerRect;                          // Inner rectangle (omit title bar, menu bar, scroll bar)
+    ImRect                  InnerClipRect;                      // == InnerRect shrunk by WindowPadding*0.5f on each side, clipped within viewport or parent clip rect.
+    ImRect                  WorkRect;                           // Cover the whole scrolling region, shrunk by WindowPadding*1.0f on each side. This is meant to replace ContentRegionRect over time (from 1.71+ onward).
+    ImRect                  ClipRect;                           // Current clipping/scissoring rectangle, evolve as we are using PushClipRect(), etc. == DrawList->clip_rect_stack.back().
+    ImRect                  ContentRegionRect;                  // FIXME: This is currently confusing/misleading. It is essentially WorkRect but not handling of scrolling. We currently rely on it as right/bottom aligned sizing operation need some size to rely on.
+
+    int                     LastFrameActive;                    // Last frame number the window was Active.
+    float                   LastTimeActive;                     // Last timestamp the window was Active (using float as we don't need high precision there)
+    float                   ItemWidthDefault;
+    ImGuiStorage            StateStorage;
+    ImVector<ImGuiColumns>  ColumnsStorage;
+    float                   FontWindowScale;                    // User scale multiplier per-window, via SetWindowFontScale()
+    int                     SettingsOffset;                     // Offset into SettingsWindows[] (offsets are always valid as we only grow the array from the back)
+
+    ImDrawList*             DrawList;                           // == &DrawListInst (for backward compatibility reason with code using imgui_internal.h we keep this a pointer)
+    ImDrawList              DrawListInst;
+    ImGuiWindow*            ParentWindow;                       // If we are a child _or_ popup window, this is pointing to our parent. Otherwise NULL.
+    ImGuiWindow*            RootWindow;                         // Point to ourself or first ancestor that is not a child window.
+    ImGuiWindow*            RootWindowForTitleBarHighlight;     // Point to ourself or first ancestor which will display TitleBgActive color when this window is active.
+    ImGuiWindow*            RootWindowForNav;                   // Point to ourself or first ancestor which doesn't have the NavFlattened flag.
+
+    ImGuiWindow*            NavLastChildNavWindow;              // When going to the menu bar, we remember the child window we came from. (This could probably be made implicit if we kept g.Windows sorted by last focused including child window.)
+    ImGuiID                 NavLastIds[ImGuiNavLayer_COUNT];    // Last known NavId for this window, per layer (0/1)
+    ImRect                  NavRectRel[ImGuiNavLayer_COUNT];    // Reference rectangle, in window relative space
+
+    bool                    MemoryCompacted;
+    int                     MemoryDrawListIdxCapacity;
+    int                     MemoryDrawListVtxCapacity;
+
+public:
+    ImGuiWindow(ImGuiContext* context, const char* name);
+    ~ImGuiWindow();
+
+    ImGuiID     GetID(const char* str, const char* str_end = NULL);
+    ImGuiID     GetID(const void* ptr);
+    ImGuiID     GetID(int n);
+    ImGuiID     GetIDNoKeepAlive(const char* str, const char* str_end = NULL);
+    ImGuiID     GetIDNoKeepAlive(const void* ptr);
+    ImGuiID     GetIDNoKeepAlive(int n);
+    ImGuiID     GetIDFromRectangle(const ImRect& r_abs);
+
+    // We don't use g.FontSize because the window may be != g.CurrentWidow.
+    ImRect      Rect() const                { return ImRect(Pos.x, Pos.y, Pos.x+Size.x, Pos.y+Size.y); }
+    float       CalcFontSize() const        { ImGuiContext& g = *GImGui; float scale = g.FontBaseSize * FontWindowScale; if (ParentWindow) scale *= ParentWindow->FontWindowScale; return scale; }
+    float       TitleBarHeight() const      { ImGuiContext& g = *GImGui; return (Flags & ImGuiWindowFlags_NoTitleBar) ? 0.0f : CalcFontSize() + g.Style.FramePadding.y * 2.0f; }
+    ImRect      TitleBarRect() const        { return ImRect(Pos, ImVec2(Pos.x + SizeFull.x, Pos.y + TitleBarHeight())); }
+    float       MenuBarHeight() const       { ImGuiContext& g = *GImGui; return (Flags & ImGuiWindowFlags_MenuBar) ? DC.MenuBarOffset.y + CalcFontSize() + g.Style.FramePadding.y * 2.0f : 0.0f; }
+    ImRect      MenuBarRect() const         { float y1 = Pos.y + TitleBarHeight(); return ImRect(Pos.x, y1, Pos.x + SizeFull.x, y1 + MenuBarHeight()); }
+};
+
+// Backup and restore just enough data to be able to use IsItemHovered() on item A after another B in the same window has overwritten the data.
+struct ImGuiItemHoveredDataBackup
+{
+    ImGuiID                 LastItemId;
+    ImGuiItemStatusFlags    LastItemStatusFlags;
+    ImRect                  LastItemRect;
+    ImRect                  LastItemDisplayRect;
+
+    ImGuiItemHoveredDataBackup() { Backup(); }
+    void Backup()           { ImGuiWindow* window = GImGui->CurrentWindow; LastItemId = window->DC.LastItemId; LastItemStatusFlags = window->DC.LastItemStatusFlags; LastItemRect = window->DC.LastItemRect; LastItemDisplayRect = window->DC.LastItemDisplayRect; }
+    void Restore() const    { ImGuiWindow* window = GImGui->CurrentWindow; window->DC.LastItemId = LastItemId; window->DC.LastItemStatusFlags = LastItemStatusFlags; window->DC.LastItemRect = LastItemRect; window->DC.LastItemDisplayRect = LastItemDisplayRect; }
+};
+
+//-----------------------------------------------------------------------------
+// Tab bar, tab item
+//-----------------------------------------------------------------------------
+
+// Extend ImGuiTabBarFlags_
+enum ImGuiTabBarFlagsPrivate_
+{
+    ImGuiTabBarFlags_DockNode                   = 1 << 20,  // Part of a dock node [we don't use this in the master branch but it facilitate branch syncing to keep this around]
+    ImGuiTabBarFlags_IsFocused                  = 1 << 21,
+    ImGuiTabBarFlags_SaveSettings               = 1 << 22   // FIXME: Settings are handled by the docking system, this only request the tab bar to mark settings dirty when reordering tabs
+};
+
+// Extend ImGuiTabItemFlags_
+enum ImGuiTabItemFlagsPrivate_
+{
+    ImGuiTabItemFlags_NoCloseButton             = 1 << 20   // Track whether p_open was set or not (we'll need this info on the next frame to recompute ContentWidth during layout)
+};
+
+// Storage for one active tab item (sizeof() 26~32 bytes)
+struct ImGuiTabItem
+{
+    ImGuiID             ID;
+    ImGuiTabItemFlags   Flags;
+    int                 LastFrameVisible;
+    int                 LastFrameSelected;      // This allows us to infer an ordered list of the last activated tabs with little maintenance
+    int                 NameOffset;             // When Window==NULL, offset to name within parent ImGuiTabBar::TabsNames
+    float               Offset;                 // Position relative to beginning of tab
+    float               Width;                  // Width currently displayed
+    float               ContentWidth;           // Width of actual contents, stored during BeginTabItem() call
+
+    ImGuiTabItem()      { ID = 0; Flags = ImGuiTabItemFlags_None; LastFrameVisible = LastFrameSelected = -1; NameOffset = -1; Offset = Width = ContentWidth = 0.0f; }
+};
+
+// Storage for a tab bar (sizeof() 92~96 bytes)
+struct ImGuiTabBar
+{
+    ImVector<ImGuiTabItem> Tabs;
+    ImGuiID             ID;                     // Zero for tab-bars used by docking
+    ImGuiID             SelectedTabId;          // Selected tab/window
+    ImGuiID             NextSelectedTabId;
+    ImGuiID             VisibleTabId;           // Can occasionally be != SelectedTabId (e.g. when previewing contents for CTRL+TAB preview)
+    int                 CurrFrameVisible;
+    int                 PrevFrameVisible;
+    ImRect              BarRect;
+    float               LastTabContentHeight;   // Record the height of contents submitted below the tab bar
+    float               OffsetMax;              // Distance from BarRect.Min.x, locked during layout
+    float               OffsetMaxIdeal;         // Ideal offset if all tabs were visible and not clipped
+    float               OffsetNextTab;          // Distance from BarRect.Min.x, incremented with each BeginTabItem() call, not used if ImGuiTabBarFlags_Reorderable if set.
+    float               ScrollingAnim;
+    float               ScrollingTarget;
+    float               ScrollingTargetDistToVisibility;
+    float               ScrollingSpeed;
+    ImGuiTabBarFlags    Flags;
+    ImGuiID             ReorderRequestTabId;
+    ImS8                ReorderRequestDir;
+    bool                WantLayout;
+    bool                VisibleTabWasSubmitted;
+    short               LastTabItemIdx;         // For BeginTabItem()/EndTabItem()
+    ImVec2              FramePadding;           // style.FramePadding locked at the time of BeginTabBar()
+    ImGuiTextBuffer     TabsNames;              // For non-docking tab bar we re-append names in a contiguous buffer.
+
+    ImGuiTabBar();
+    int                 GetTabOrder(const ImGuiTabItem* tab) const  { return Tabs.index_from_ptr(tab); }
+    const char*         GetTabName(const ImGuiTabItem* tab) const
+    {
+        IM_ASSERT(tab->NameOffset != -1 && tab->NameOffset < TabsNames.Buf.Size);
+        return TabsNames.Buf.Data + tab->NameOffset;
+    }
+};
+
+//-----------------------------------------------------------------------------
+// Internal API
+// No guarantee of forward compatibility here.
+//-----------------------------------------------------------------------------
+
+namespace ImGui
+{
+    // Windows
+    // We should always have a CurrentWindow in the stack (there is an implicit "Debug" window)
+    // If this ever crash because g.CurrentWindow is NULL it means that either
+    // - ImGui::NewFrame() has never been called, which is illegal.
+    // - You are calling ImGui functions after ImGui::EndFrame()/ImGui::Render() and before the next ImGui::NewFrame(), which is also illegal.
+    inline    ImGuiWindow*  GetCurrentWindowRead()      { ImGuiContext& g = *GImGui; return g.CurrentWindow; }
+    inline    ImGuiWindow*  GetCurrentWindow()          { ImGuiContext& g = *GImGui; g.CurrentWindow->WriteAccessed = true; return g.CurrentWindow; }
+    IMGUI_API ImGuiWindow*  FindWindowByID(ImGuiID id);
+    IMGUI_API ImGuiWindow*  FindWindowByName(const char* name);
+    IMGUI_API void          UpdateWindowParentAndRootLinks(ImGuiWindow* window, ImGuiWindowFlags flags, ImGuiWindow* parent_window);
+    IMGUI_API ImVec2        CalcWindowExpectedSize(ImGuiWindow* window);
+    IMGUI_API bool          IsWindowChildOf(ImGuiWindow* window, ImGuiWindow* potential_parent);
+    IMGUI_API bool          IsWindowNavFocusable(ImGuiWindow* window);
+    IMGUI_API ImRect        GetWindowAllowedExtentRect(ImGuiWindow* window);
+    IMGUI_API void          SetWindowPos(ImGuiWindow* window, const ImVec2& pos, ImGuiCond cond = 0);
+    IMGUI_API void          SetWindowSize(ImGuiWindow* window, const ImVec2& size, ImGuiCond cond = 0);
+    IMGUI_API void          SetWindowCollapsed(ImGuiWindow* window, bool collapsed, ImGuiCond cond = 0);
+
+    // Windows: Display Order and Focus Order
+    IMGUI_API void          FocusWindow(ImGuiWindow* window);
+    IMGUI_API void          FocusTopMostWindowUnderOne(ImGuiWindow* under_this_window, ImGuiWindow* ignore_window);
+    IMGUI_API void          BringWindowToFocusFront(ImGuiWindow* window);
+    IMGUI_API void          BringWindowToDisplayFront(ImGuiWindow* window);
+    IMGUI_API void          BringWindowToDisplayBack(ImGuiWindow* window);
+
+    // Fonts, drawing
+    IMGUI_API void          SetCurrentFont(ImFont* font);
+    inline ImFont*          GetDefaultFont() { ImGuiContext& g = *GImGui; return g.IO.FontDefault ? g.IO.FontDefault : g.IO.Fonts->Fonts[0]; }
+    inline ImDrawList*      GetForegroundDrawList(ImGuiWindow* window) { IM_UNUSED(window); ImGuiContext& g = *GImGui; return &g.ForegroundDrawList; } // This seemingly unnecessary wrapper simplifies compatibility between the 'master' and 'docking' branches.
+
+    // Init
+    IMGUI_API void          Initialize(ImGuiContext* context);
+    IMGUI_API void          Shutdown(ImGuiContext* context);    // Since 1.60 this is a _private_ function. You can call DestroyContext() to destroy the context created by CreateContext().
+
+    // NewFrame
+    IMGUI_API void          UpdateHoveredWindowAndCaptureFlags();
+    IMGUI_API void          StartMouseMovingWindow(ImGuiWindow* window);
+    IMGUI_API void          UpdateMouseMovingWindowNewFrame();
+    IMGUI_API void          UpdateMouseMovingWindowEndFrame();
+
+    // Settings
+    IMGUI_API void                  MarkIniSettingsDirty();
+    IMGUI_API void                  MarkIniSettingsDirty(ImGuiWindow* window);
+    IMGUI_API ImGuiWindowSettings*  CreateNewWindowSettings(const char* name);
+    IMGUI_API ImGuiWindowSettings*  FindWindowSettings(ImGuiID id);
+    IMGUI_API ImGuiWindowSettings*  FindOrCreateWindowSettings(const char* name);
+    IMGUI_API ImGuiSettingsHandler* FindSettingsHandler(const char* type_name);
+
+    // Scrolling
+    IMGUI_API void          SetNextWindowScroll(const ImVec2& scroll); // Use -1.0f on one axis to leave as-is
+    IMGUI_API void          SetScrollX(ImGuiWindow* window, float new_scroll_x);
+    IMGUI_API void          SetScrollY(ImGuiWindow* window, float new_scroll_y);
+    IMGUI_API void          SetScrollFromPosX(ImGuiWindow* window, float local_x, float center_x_ratio = 0.5f);
+    IMGUI_API void          SetScrollFromPosY(ImGuiWindow* window, float local_y, float center_y_ratio = 0.5f);
+    IMGUI_API ImVec2        ScrollToBringRectIntoView(ImGuiWindow* window, const ImRect& item_rect);
+
+    // Basic Accessors
+    inline ImGuiID          GetItemID()     { ImGuiContext& g = *GImGui; return g.CurrentWindow->DC.LastItemId; }
+    inline ImGuiItemStatusFlags GetItemStatusFlags() { ImGuiContext& g = *GImGui; return g.CurrentWindow->DC.LastItemStatusFlags; }
+    inline ImGuiID          GetActiveID()   { ImGuiContext& g = *GImGui; return g.ActiveId; }
+    inline ImGuiID          GetFocusID()    { ImGuiContext& g = *GImGui; return g.NavId; }
+    IMGUI_API void          SetActiveID(ImGuiID id, ImGuiWindow* window);
+    IMGUI_API void          SetFocusID(ImGuiID id, ImGuiWindow* window);
+    IMGUI_API void          ClearActiveID();
+    IMGUI_API ImGuiID       GetHoveredID();
+    IMGUI_API void          SetHoveredID(ImGuiID id);
+    IMGUI_API void          KeepAliveID(ImGuiID id);
+    IMGUI_API void          MarkItemEdited(ImGuiID id);     // Mark data associated to given item as "edited", used by IsItemDeactivatedAfterEdit() function.
+    IMGUI_API void          PushOverrideID(ImGuiID id);     // Push given value at the top of the ID stack (whereas PushID combines old and new hashes)
+
+    // Basic Helpers for widget code
+    IMGUI_API void          ItemSize(const ImVec2& size, float text_baseline_y = -1.0f);
+    IMGUI_API void          ItemSize(const ImRect& bb, float text_baseline_y = -1.0f);
+    IMGUI_API bool          ItemAdd(const ImRect& bb, ImGuiID id, const ImRect* nav_bb = NULL);
+    IMGUI_API bool          ItemHoverable(const ImRect& bb, ImGuiID id);
+    IMGUI_API bool          IsClippedEx(const ImRect& bb, ImGuiID id, bool clip_even_when_logged);
+    IMGUI_API bool          FocusableItemRegister(ImGuiWindow* window, ImGuiID id);   // Return true if focus is requested
+    IMGUI_API void          FocusableItemUnregister(ImGuiWindow* window);
+    IMGUI_API ImVec2        CalcItemSize(ImVec2 size, float default_w, float default_h);
+    IMGUI_API float         CalcWrapWidthForPos(const ImVec2& pos, float wrap_pos_x);
+    IMGUI_API void          PushMultiItemsWidths(int components, float width_full);
+    IMGUI_API void          PushItemFlag(ImGuiItemFlags option, bool enabled);
+    IMGUI_API void          PopItemFlag();
+    IMGUI_API bool          IsItemToggledSelection();                           // Was the last item selection toggled? (after Selectable(), TreeNode() etc. We only returns toggle _event_ in order to handle clipping correctly)
+    IMGUI_API ImVec2        GetContentRegionMaxAbs();
+    IMGUI_API void          ShrinkWidths(ImGuiShrinkWidthItem* items, int count, float width_excess);
+
+    // Logging/Capture
+    IMGUI_API void          LogBegin(ImGuiLogType type, int auto_open_depth);   // -> BeginCapture() when we design v2 api, for now stay under the radar by using the old name.
+    IMGUI_API void          LogToBuffer(int auto_open_depth = -1);              // Start logging/capturing to internal buffer
+
+    // Popups, Modals, Tooltips
+    IMGUI_API bool          BeginChildEx(const char* name, ImGuiID id, const ImVec2& size_arg, bool border, ImGuiWindowFlags flags);
+    IMGUI_API void          OpenPopupEx(ImGuiID id);
+    IMGUI_API void          ClosePopupToLevel(int remaining, bool restore_focus_to_window_under_popup);
+    IMGUI_API void          ClosePopupsOverWindow(ImGuiWindow* ref_window, bool restore_focus_to_window_under_popup);
+    IMGUI_API bool          IsPopupOpen(ImGuiID id); // Test for id within current popup stack level (currently begin-ed into); this doesn't scan the whole popup stack!
+    IMGUI_API bool          BeginPopupEx(ImGuiID id, ImGuiWindowFlags extra_flags);
+    IMGUI_API void          BeginTooltipEx(ImGuiWindowFlags extra_flags, ImGuiTooltipFlags tooltip_flags);
+    IMGUI_API ImGuiWindow*  GetTopMostPopupModal();
+    IMGUI_API ImVec2        FindBestWindowPosForPopup(ImGuiWindow* window);
+    IMGUI_API ImVec2        FindBestWindowPosForPopupEx(const ImVec2& ref_pos, const ImVec2& size, ImGuiDir* last_dir, const ImRect& r_outer, const ImRect& r_avoid, ImGuiPopupPositionPolicy policy = ImGuiPopupPositionPolicy_Default);
+
+    // Navigation
+    IMGUI_API void          NavInitWindow(ImGuiWindow* window, bool force_reinit);
+    IMGUI_API bool          NavMoveRequestButNoResultYet();
+    IMGUI_API void          NavMoveRequestCancel();
+    IMGUI_API void          NavMoveRequestForward(ImGuiDir move_dir, ImGuiDir clip_dir, const ImRect& bb_rel, ImGuiNavMoveFlags move_flags);
+    IMGUI_API void          NavMoveRequestTryWrapping(ImGuiWindow* window, ImGuiNavMoveFlags move_flags);
+    IMGUI_API float         GetNavInputAmount(ImGuiNavInput n, ImGuiInputReadMode mode);
+    IMGUI_API ImVec2        GetNavInputAmount2d(ImGuiNavDirSourceFlags dir_sources, ImGuiInputReadMode mode, float slow_factor = 0.0f, float fast_factor = 0.0f);
+    IMGUI_API int           CalcTypematicRepeatAmount(float t0, float t1, float repeat_delay, float repeat_rate);
+    IMGUI_API void          ActivateItem(ImGuiID id);   // Remotely activate a button, checkbox, tree node etc. given its unique ID. activation is queued and processed on the next frame when the item is encountered again.
+    IMGUI_API void          SetNavID(ImGuiID id, int nav_layer, ImGuiID focus_scope_id);
+    IMGUI_API void          SetNavIDWithRectRel(ImGuiID id, int nav_layer, ImGuiID focus_scope_id, const ImRect& rect_rel);
+
+    // Focus scope (WIP)
+    IMGUI_API void          PushFocusScope(ImGuiID id);     // Note: this is storing in same stack as IDStack, so Push/Pop mismatch will be reported there.
+    IMGUI_API void          PopFocusScope();
+    inline ImGuiID          GetFocusScopeID()               { ImGuiContext& g = *GImGui; return g.NavFocusScopeId; }
+
+    // Inputs
+    // FIXME: Eventually we should aim to move e.g. IsActiveIdUsingKey() into IsKeyXXX functions.
+    inline bool             IsActiveIdUsingNavDir(ImGuiDir dir)                         { ImGuiContext& g = *GImGui; return (g.ActiveIdUsingNavDirMask & (1 << dir)) != 0; }
+    inline bool             IsActiveIdUsingNavInput(ImGuiNavInput input)                { ImGuiContext& g = *GImGui; return (g.ActiveIdUsingNavInputMask & (1 << input)) != 0; }
+    inline bool             IsActiveIdUsingKey(ImGuiKey key)                            { ImGuiContext& g = *GImGui; IM_ASSERT(key < 64); return (g.ActiveIdUsingKeyInputMask & ((ImU64)1 << key)) != 0; }
+    IMGUI_API bool          IsMouseDragPastThreshold(ImGuiMouseButton button, float lock_threshold = -1.0f);
+    inline bool             IsKeyPressedMap(ImGuiKey key, bool repeat = true)           { ImGuiContext& g = *GImGui; const int key_index = g.IO.KeyMap[key]; return (key_index >= 0) ? IsKeyPressed(key_index, repeat) : false; }
+    inline bool             IsNavInputDown(ImGuiNavInput n)                             { ImGuiContext& g = *GImGui; return g.IO.NavInputs[n] > 0.0f; }
+    inline bool             IsNavInputTest(ImGuiNavInput n, ImGuiInputReadMode rm)      { return (GetNavInputAmount(n, rm) > 0.0f); }
+    IMGUI_API ImGuiKeyModFlags GetMergedKeyModFlags();
+
+    // Drag and Drop
+    IMGUI_API bool          BeginDragDropTargetCustom(const ImRect& bb, ImGuiID id);
+    IMGUI_API void          ClearDragDrop();
+    IMGUI_API bool          IsDragDropPayloadBeingAccepted();
+
+    // Internal Columns API (this is not exposed because we will encourage transitioning to the Tables api)
+    IMGUI_API void          BeginColumns(const char* str_id, int count, ImGuiColumnsFlags flags = 0); // setup number of columns. use an identifier to distinguish multiple column sets. close with EndColumns().
+    IMGUI_API void          EndColumns();                                                             // close columns
+    IMGUI_API void          PushColumnClipRect(int column_index);
+    IMGUI_API void          PushColumnsBackground();
+    IMGUI_API void          PopColumnsBackground();
+    IMGUI_API ImGuiID       GetColumnsID(const char* str_id, int count);
+    IMGUI_API ImGuiColumns* FindOrCreateColumns(ImGuiWindow* window, ImGuiID id);
+    IMGUI_API float         GetColumnOffsetFromNorm(const ImGuiColumns* columns, float offset_norm);
+    IMGUI_API float         GetColumnNormFromOffset(const ImGuiColumns* columns, float offset);
+
+    // Tab Bars
+    IMGUI_API bool          BeginTabBarEx(ImGuiTabBar* tab_bar, const ImRect& bb, ImGuiTabBarFlags flags);
+    IMGUI_API ImGuiTabItem* TabBarFindTabByID(ImGuiTabBar* tab_bar, ImGuiID tab_id);
+    IMGUI_API void          TabBarRemoveTab(ImGuiTabBar* tab_bar, ImGuiID tab_id);
+    IMGUI_API void          TabBarCloseTab(ImGuiTabBar* tab_bar, ImGuiTabItem* tab);
+    IMGUI_API void          TabBarQueueChangeTabOrder(ImGuiTabBar* tab_bar, const ImGuiTabItem* tab, int dir);
+    IMGUI_API bool          TabItemEx(ImGuiTabBar* tab_bar, const char* label, bool* p_open, ImGuiTabItemFlags flags);
+    IMGUI_API ImVec2        TabItemCalcSize(const char* label, bool has_close_button);
+    IMGUI_API void          TabItemBackground(ImDrawList* draw_list, const ImRect& bb, ImGuiTabItemFlags flags, ImU32 col);
+    IMGUI_API bool          TabItemLabelAndCloseButton(ImDrawList* draw_list, const ImRect& bb, ImGuiTabItemFlags flags, ImVec2 frame_padding, const char* label, ImGuiID tab_id, ImGuiID close_button_id);
+
+    // Render helpers
+    // AVOID USING OUTSIDE OF IMGUI.CPP! NOT FOR PUBLIC CONSUMPTION. THOSE FUNCTIONS ARE A MESS. THEIR SIGNATURE AND BEHAVIOR WILL CHANGE, THEY NEED TO BE REFACTORED INTO SOMETHING DECENT.
+    // NB: All position are in absolute pixels coordinates (we are never using window coordinates internally)
+    IMGUI_API void          RenderText(ImVec2 pos, const char* text, const char* text_end = NULL, bool hide_text_after_hash = true);
+    IMGUI_API void          RenderTextWrapped(ImVec2 pos, const char* text, const char* text_end, float wrap_width);
+    IMGUI_API void          RenderTextClipped(const ImVec2& pos_min, const ImVec2& pos_max, const char* text, const char* text_end, const ImVec2* text_size_if_known, const ImVec2& align = ImVec2(0,0), const ImRect* clip_rect = NULL);
+    IMGUI_API void          RenderTextClippedEx(ImDrawList* draw_list, const ImVec2& pos_min, const ImVec2& pos_max, const char* text, const char* text_end, const ImVec2* text_size_if_known, const ImVec2& align = ImVec2(0, 0), const ImRect* clip_rect = NULL);
+    IMGUI_API void          RenderTextEllipsis(ImDrawList* draw_list, const ImVec2& pos_min, const ImVec2& pos_max, float clip_max_x, float ellipsis_max_x, const char* text, const char* text_end, const ImVec2* text_size_if_known);
+    IMGUI_API void          RenderFrame(ImVec2 p_min, ImVec2 p_max, ImU32 fill_col, bool border = true, float rounding = 0.0f);
+    IMGUI_API void          RenderFrameBorder(ImVec2 p_min, ImVec2 p_max, float rounding = 0.0f);
+    IMGUI_API void          RenderColorRectWithAlphaCheckerboard(ImDrawList* draw_list, ImVec2 p_min, ImVec2 p_max, ImU32 fill_col, float grid_step, ImVec2 grid_off, float rounding = 0.0f, int rounding_corners_flags = ~0);
+    IMGUI_API void          RenderNavHighlight(const ImRect& bb, ImGuiID id, ImGuiNavHighlightFlags flags = ImGuiNavHighlightFlags_TypeDefault); // Navigation highlight
+    IMGUI_API const char*   FindRenderedTextEnd(const char* text, const char* text_end = NULL); // Find the optional ## from which we stop displaying text.
+    IMGUI_API void          LogRenderedText(const ImVec2* ref_pos, const char* text, const char* text_end = NULL);
+
+    // Render helpers (those functions don't access any ImGui state!)
+    IMGUI_API void          RenderArrow(ImDrawList* draw_list, ImVec2 pos, ImU32 col, ImGuiDir dir, float scale = 1.0f);
+    IMGUI_API void          RenderBullet(ImDrawList* draw_list, ImVec2 pos, ImU32 col);
+    IMGUI_API void          RenderCheckMark(ImDrawList* draw_list, ImVec2 pos, ImU32 col, float sz);
+    IMGUI_API void          RenderMouseCursor(ImDrawList* draw_list, ImVec2 pos, float scale, ImGuiMouseCursor mouse_cursor, ImU32 col_fill, ImU32 col_border, ImU32 col_shadow);
+    IMGUI_API void          RenderArrowPointingAt(ImDrawList* draw_list, ImVec2 pos, ImVec2 half_sz, ImGuiDir direction, ImU32 col);
+    IMGUI_API void          RenderRectFilledRangeH(ImDrawList* draw_list, const ImRect& rect, ImU32 col, float x_start_norm, float x_end_norm, float rounding);
+
+#ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
+    // [1.71: 2019/06/07: Updating prototypes of some of the internal functions. Leaving those for reference for a short while]
+    inline void RenderArrow(ImVec2 pos, ImGuiDir dir, float scale=1.0f) { ImGuiWindow* window = GetCurrentWindow(); RenderArrow(window->DrawList, pos, GetColorU32(ImGuiCol_Text), dir, scale); }
+    inline void RenderBullet(ImVec2 pos)                                { ImGuiWindow* window = GetCurrentWindow(); RenderBullet(window->DrawList, pos, GetColorU32(ImGuiCol_Text)); }
+#endif
+
+    // Widgets
+    IMGUI_API void          TextEx(const char* text, const char* text_end = NULL, ImGuiTextFlags flags = 0);
+    IMGUI_API bool          ButtonEx(const char* label, const ImVec2& size_arg = ImVec2(0,0), ImGuiButtonFlags flags = 0);
+    IMGUI_API bool          CloseButton(ImGuiID id, const ImVec2& pos);
+    IMGUI_API bool          CollapseButton(ImGuiID id, const ImVec2& pos);
+    IMGUI_API bool          ArrowButtonEx(const char* str_id, ImGuiDir dir, ImVec2 size_arg, ImGuiButtonFlags flags = 0);
+    IMGUI_API void          Scrollbar(ImGuiAxis axis);
+    IMGUI_API bool          ScrollbarEx(const ImRect& bb, ImGuiID id, ImGuiAxis axis, float* p_scroll_v, float avail_v, float contents_v, ImDrawCornerFlags rounding_corners);
+    IMGUI_API ImRect        GetWindowScrollbarRect(ImGuiWindow* window, ImGuiAxis axis);
+    IMGUI_API ImGuiID       GetWindowScrollbarID(ImGuiWindow* window, ImGuiAxis axis);
+    IMGUI_API ImGuiID       GetWindowResizeID(ImGuiWindow* window, int n); // 0..3: corners, 4..7: borders
+    IMGUI_API void          SeparatorEx(ImGuiSeparatorFlags flags);
+
+    // Widgets low-level behaviors
+    IMGUI_API bool          ButtonBehavior(const ImRect& bb, ImGuiID id, bool* out_hovered, bool* out_held, ImGuiButtonFlags flags = 0);
+    IMGUI_API bool          DragBehavior(ImGuiID id, ImGuiDataType data_type, void* p_v, float v_speed, const void* p_min, const void* p_max, const char* format, float power, ImGuiDragFlags flags);
+    IMGUI_API bool          SliderBehavior(const ImRect& bb, ImGuiID id, ImGuiDataType data_type, void* p_v, const void* p_min, const void* p_max, const char* format, float power, ImGuiSliderFlags flags, ImRect* out_grab_bb);
+    IMGUI_API bool          SplitterBehavior(const ImRect& bb, ImGuiID id, ImGuiAxis axis, float* size1, float* size2, float min_size1, float min_size2, float hover_extend = 0.0f, float hover_visibility_delay = 0.0f);
+    IMGUI_API bool          TreeNodeBehavior(ImGuiID id, ImGuiTreeNodeFlags flags, const char* label, const char* label_end = NULL);
+    IMGUI_API bool          TreeNodeBehaviorIsOpen(ImGuiID id, ImGuiTreeNodeFlags flags = 0);                     // Consume previous SetNextItemOpen() data, if any. May return true when logging
+    IMGUI_API void          TreePushOverrideID(ImGuiID id);
+
+    // Template functions are instantiated in imgui_widgets.cpp for a finite number of types.
+    // To use them externally (for custom widget) you may need an "extern template" statement in your code in order to link to existing instances and silence Clang warnings (see #2036).
+    // e.g. " extern template IMGUI_API float RoundScalarWithFormatT<float, float>(const char* format, ImGuiDataType data_type, float v); "
+    template<typename T, typename SIGNED_T, typename FLOAT_T>   IMGUI_API bool  DragBehaviorT(ImGuiDataType data_type, T* v, float v_speed, T v_min, T v_max, const char* format, float power, ImGuiDragFlags flags);
+    template<typename T, typename SIGNED_T, typename FLOAT_T>   IMGUI_API bool  SliderBehaviorT(const ImRect& bb, ImGuiID id, ImGuiDataType data_type, T* v, T v_min, T v_max, const char* format, float power, ImGuiSliderFlags flags, ImRect* out_grab_bb);
+    template<typename T, typename FLOAT_T>                      IMGUI_API float SliderCalcRatioFromValueT(ImGuiDataType data_type, T v, T v_min, T v_max, float power, float linear_zero_pos);
+    template<typename T, typename SIGNED_T>                     IMGUI_API T     RoundScalarWithFormatT(const char* format, ImGuiDataType data_type, T v);
+
+    // Data type helpers
+    IMGUI_API const ImGuiDataTypeInfo*  DataTypeGetInfo(ImGuiDataType data_type);
+    IMGUI_API int           DataTypeFormatString(char* buf, int buf_size, ImGuiDataType data_type, const void* p_data, const char* format);
+    IMGUI_API void          DataTypeApplyOp(ImGuiDataType data_type, int op, void* output, void* arg_1, const void* arg_2);
+    IMGUI_API bool          DataTypeApplyOpFromText(const char* buf, const char* initial_value_buf, ImGuiDataType data_type, void* p_data, const char* format);
+
+    // InputText
+    IMGUI_API bool          InputTextEx(const char* label, const char* hint, char* buf, int buf_size, const ImVec2& size_arg, ImGuiInputTextFlags flags, ImGuiInputTextCallback callback = NULL, void* user_data = NULL);
+    IMGUI_API bool          TempInputText(const ImRect& bb, ImGuiID id, const char* label, char* buf, int buf_size, ImGuiInputTextFlags flags);
+    IMGUI_API bool          TempInputScalar(const ImRect& bb, ImGuiID id, const char* label, ImGuiDataType data_type, void* p_data, const char* format);
+    inline bool             TempInputIsActive(ImGuiID id)       { ImGuiContext& g = *GImGui; return (g.ActiveId == id && g.TempInputId == id); }
+    inline ImGuiInputTextState* GetInputTextState(ImGuiID id)   { ImGuiContext& g = *GImGui; return (g.InputTextState.ID == id) ? &g.InputTextState : NULL; } // Get input text state if active
+
+    // Color
+    IMGUI_API void          ColorTooltip(const char* text, const float* col, ImGuiColorEditFlags flags);
+    IMGUI_API void          ColorEditOptionsPopup(const float* col, ImGuiColorEditFlags flags);
+    IMGUI_API void          ColorPickerOptionsPopup(const float* ref_col, ImGuiColorEditFlags flags);
+
+    // Plot
+    IMGUI_API int           PlotEx(ImGuiPlotType plot_type, const char* label, float (*values_getter)(void* data, int idx), void* data, int values_count, int values_offset, const char* overlay_text, float scale_min, float scale_max, ImVec2 frame_size);
+
+    // Shade functions (write over already created vertices)
+    IMGUI_API void          ShadeVertsLinearColorGradientKeepAlpha(ImDrawList* draw_list, int vert_start_idx, int vert_end_idx, ImVec2 gradient_p0, ImVec2 gradient_p1, ImU32 col0, ImU32 col1);
+    IMGUI_API void          ShadeVertsLinearUV(ImDrawList* draw_list, int vert_start_idx, int vert_end_idx, const ImVec2& a, const ImVec2& b, const ImVec2& uv_a, const ImVec2& uv_b, bool clamp);
+
+    // Garbage collection
+    IMGUI_API void          GcCompactTransientWindowBuffers(ImGuiWindow* window);
+    IMGUI_API void          GcAwakeTransientWindowBuffers(ImGuiWindow* window);
+
+    // Debug Tools
+    inline void             DebugDrawItemRect(ImU32 col = IM_COL32(255,0,0,255))    { ImGuiContext& g = *GImGui; ImGuiWindow* window = g.CurrentWindow; GetForegroundDrawList(window)->AddRect(window->DC.LastItemRect.Min, window->DC.LastItemRect.Max, col); }
+    inline void             DebugStartItemPicker()                                  { ImGuiContext& g = *GImGui; g.DebugItemPickerActive = true; }
+
+} // namespace ImGui
+
+// ImFontAtlas internals
+IMGUI_API bool              ImFontAtlasBuildWithStbTruetype(ImFontAtlas* atlas);
+IMGUI_API void              ImFontAtlasBuildInit(ImFontAtlas* atlas);
+IMGUI_API void              ImFontAtlasBuildSetupFont(ImFontAtlas* atlas, ImFont* font, ImFontConfig* font_config, float ascent, float descent);
+IMGUI_API void              ImFontAtlasBuildPackCustomRects(ImFontAtlas* atlas, void* stbrp_context_opaque);
+IMGUI_API void              ImFontAtlasBuildFinish(ImFontAtlas* atlas);
+IMGUI_API void              ImFontAtlasBuildMultiplyCalcLookupTable(unsigned char out_table[256], float in_multiply_factor);
+IMGUI_API void              ImFontAtlasBuildMultiplyRectAlpha8(const unsigned char table[256], unsigned char* pixels, int x, int y, int w, int h, int stride);
+
+// Debug Tools
+// Use 'Metrics->Tools->Item Picker' to break into the call-stack of a specific item.
+#ifndef IM_DEBUG_BREAK
+#if defined(__clang__)
+#define IM_DEBUG_BREAK()    __builtin_debugtrap()
+#elif defined (_MSC_VER)
+#define IM_DEBUG_BREAK()    __debugbreak()
+#else
+#define IM_DEBUG_BREAK()    IM_ASSERT(0)    // It is expected that you define IM_DEBUG_BREAK() into something that will break nicely in a debugger!
+#endif
+#endif // #ifndef IM_DEBUG_BREAK
+
+// Test Engine Hooks (imgui_tests)
+//#define IMGUI_ENABLE_TEST_ENGINE
+#ifdef IMGUI_ENABLE_TEST_ENGINE
+extern void                 ImGuiTestEngineHook_PreNewFrame(ImGuiContext* ctx);
+extern void                 ImGuiTestEngineHook_PostNewFrame(ImGuiContext* ctx);
+extern void                 ImGuiTestEngineHook_ItemAdd(ImGuiContext* ctx, const ImRect& bb, ImGuiID id);
+extern void                 ImGuiTestEngineHook_ItemInfo(ImGuiContext* ctx, ImGuiID id, const char* label, ImGuiItemStatusFlags flags);
+extern void                 ImGuiTestEngineHook_IdInfo(ImGuiContext* ctx, ImGuiDataType data_type, ImGuiID id, const void* data_id);
+extern void                 ImGuiTestEngineHook_IdInfo(ImGuiContext* ctx, ImGuiDataType data_type, ImGuiID id, const void* data_id, const void* data_id_end);
+extern void                 ImGuiTestEngineHook_Log(ImGuiContext* ctx, const char* fmt, ...);
+#define IMGUI_TEST_ENGINE_ITEM_ADD(_BB,_ID)                 if (g.TestEngineHookItems) ImGuiTestEngineHook_ItemAdd(&g, _BB, _ID)               // Register item bounding box
+#define IMGUI_TEST_ENGINE_ITEM_INFO(_ID,_LABEL,_FLAGS)      if (g.TestEngineHookItems) ImGuiTestEngineHook_ItemInfo(&g, _ID, _LABEL, _FLAGS)   // Register item label and status flags (optional)
+#define IMGUI_TEST_ENGINE_LOG(_FMT,...)                     if (g.TestEngineHookItems) ImGuiTestEngineHook_Log(&g, _FMT, __VA_ARGS__)          // Custom log entry from user land into test log
+#define IMGUI_TEST_ENGINE_ID_INFO(_ID,_TYPE,_DATA)          if (g.TestEngineHookIdInfo == id) ImGuiTestEngineHook_IdInfo(&g, _TYPE, _ID, (const void*)(_DATA));
+#define IMGUI_TEST_ENGINE_ID_INFO2(_ID,_TYPE,_DATA,_DATA2)  if (g.TestEngineHookIdInfo == id) ImGuiTestEngineHook_IdInfo(&g, _TYPE, _ID, (const void*)(_DATA), (const void*)(_DATA2));
+#else
+#define IMGUI_TEST_ENGINE_ITEM_ADD(_BB,_ID)                 do { } while (0)
+#define IMGUI_TEST_ENGINE_ITEM_INFO(_ID,_LABEL,_FLAGS)      do { } while (0)
+#define IMGUI_TEST_ENGINE_LOG(_FMT,...)                     do { } while (0)
+#define IMGUI_TEST_ENGINE_ID_INFO(_ID,_TYPE,_DATA)          do { } while (0)
+#define IMGUI_TEST_ENGINE_ID_INFO2(_ID,_TYPE,_DATA,_DATA2)  do { } while (0)
+#endif
+
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#elif defined(__GNUC__)
+#pragma GCC diagnostic pop
+#endif
+
+#ifdef _MSC_VER
+#pragma warning (pop)
+#endif
+
+#endif // #ifndef IMGUI_DISABLE

include/imgui/imstb_rectpack.h

+// [DEAR IMGUI]
+// This is a slightly modified version of stb_rect_pack.h 1.00.
+// Those changes would need to be pushed into nothings/stb:
+// - Added STBRP__CDECL
+// Grep for [DEAR IMGUI] to find the changes.
+
+// stb_rect_pack.h - v1.00 - public domain - rectangle packing
+// Sean Barrett 2014
+//
+// Useful for e.g. packing rectangular textures into an atlas.
+// Does not do rotation.
+//
+// Not necessarily the awesomest packing method, but better than
+// the totally naive one in stb_truetype (which is primarily what
+// this is meant to replace).
+//
+// Has only had a few tests run, may have issues.
+//
+// More docs to come.
+//
+// No memory allocations; uses qsort() and assert() from stdlib.
+// Can override those by defining STBRP_SORT and STBRP_ASSERT.
+//
+// This library currently uses the Skyline Bottom-Left algorithm.
+//
+// Please note: better rectangle packers are welcome! Please
+// implement them to the same API, but with a different init
+// function.
+//
+// Credits
+//
+//  Library
+//    Sean Barrett
+//  Minor features
+//    Martins Mozeiko
+//    github:IntellectualKitty
+//    
+//  Bugfixes / warning fixes
+//    Jeremy Jaussaud
+//    Fabian Giesen
+//
+// Version history:
+//
+//     1.00  (2019-02-25)  avoid small space waste; gracefully fail too-wide rectangles
+//     0.99  (2019-02-07)  warning fixes
+//     0.11  (2017-03-03)  return packing success/fail result
+//     0.10  (2016-10-25)  remove cast-away-const to avoid warnings
+//     0.09  (2016-08-27)  fix compiler warnings
+//     0.08  (2015-09-13)  really fix bug with empty rects (w=0 or h=0)
+//     0.07  (2015-09-13)  fix bug with empty rects (w=0 or h=0)
+//     0.06  (2015-04-15)  added STBRP_SORT to allow replacing qsort
+//     0.05:  added STBRP_ASSERT to allow replacing assert
+//     0.04:  fixed minor bug in STBRP_LARGE_RECTS support
+//     0.01:  initial release
+//
+// LICENSE
+//
+//   See end of file for license information.
+
+//////////////////////////////////////////////////////////////////////////////
+//
+//       INCLUDE SECTION
+//
+
+#ifndef STB_INCLUDE_STB_RECT_PACK_H
+#define STB_INCLUDE_STB_RECT_PACK_H
+
+#define STB_RECT_PACK_VERSION  1
+
+#ifdef STBRP_STATIC
+#define STBRP_DEF static
+#else
+#define STBRP_DEF extern
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct stbrp_context stbrp_context;
+typedef struct stbrp_node    stbrp_node;
+typedef struct stbrp_rect    stbrp_rect;
+
+#ifdef STBRP_LARGE_RECTS
+typedef int            stbrp_coord;
+#else
+typedef unsigned short stbrp_coord;
+#endif
+
+STBRP_DEF int stbrp_pack_rects (stbrp_context *context, stbrp_rect *rects, int num_rects);
+// Assign packed locations to rectangles. The rectangles are of type
+// 'stbrp_rect' defined below, stored in the array 'rects', and there
+// are 'num_rects' many of them.
+//
+// Rectangles which are successfully packed have the 'was_packed' flag
+// set to a non-zero value and 'x' and 'y' store the minimum location
+// on each axis (i.e. bottom-left in cartesian coordinates, top-left
+// if you imagine y increasing downwards). Rectangles which do not fit
+// have the 'was_packed' flag set to 0.
+//
+// You should not try to access the 'rects' array from another thread
+// while this function is running, as the function temporarily reorders
+// the array while it executes.
+//
+// To pack into another rectangle, you need to call stbrp_init_target
+// again. To continue packing into the same rectangle, you can call
+// this function again. Calling this multiple times with multiple rect
+// arrays will probably produce worse packing results than calling it
+// a single time with the full rectangle array, but the option is
+// available.
+//
+// The function returns 1 if all of the rectangles were successfully
+// packed and 0 otherwise.
+
+struct stbrp_rect
+{
+   // reserved for your use:
+   int            id;
+
+   // input:
+   stbrp_coord    w, h;
+
+   // output:
+   stbrp_coord    x, y;
+   int            was_packed;  // non-zero if valid packing
+
+}; // 16 bytes, nominally
+
+
+STBRP_DEF void stbrp_init_target (stbrp_context *context, int width, int height, stbrp_node *nodes, int num_nodes);
+// Initialize a rectangle packer to:
+//    pack a rectangle that is 'width' by 'height' in dimensions
+//    using temporary storage provided by the array 'nodes', which is 'num_nodes' long
+//
+// You must call this function every time you start packing into a new target.
+//
+// There is no "shutdown" function. The 'nodes' memory must stay valid for
+// the following stbrp_pack_rects() call (or calls), but can be freed after
+// the call (or calls) finish.
+//
+// Note: to guarantee best results, either:
+//       1. make sure 'num_nodes' >= 'width'
+//   or  2. call stbrp_allow_out_of_mem() defined below with 'allow_out_of_mem = 1'
+//
+// If you don't do either of the above things, widths will be quantized to multiples
+// of small integers to guarantee the algorithm doesn't run out of temporary storage.
+//
+// If you do #2, then the non-quantized algorithm will be used, but the algorithm
+// may run out of temporary storage and be unable to pack some rectangles.
+
+STBRP_DEF void stbrp_setup_allow_out_of_mem (stbrp_context *context, int allow_out_of_mem);
+// Optionally call this function after init but before doing any packing to
+// change the handling of the out-of-temp-memory scenario, described above.
+// If you call init again, this will be reset to the default (false).
+
+
+STBRP_DEF void stbrp_setup_heuristic (stbrp_context *context, int heuristic);
+// Optionally select which packing heuristic the library should use. Different
+// heuristics will produce better/worse results for different data sets.
+// If you call init again, this will be reset to the default.
+
+enum
+{
+   STBRP_HEURISTIC_Skyline_default=0,
+   STBRP_HEURISTIC_Skyline_BL_sortHeight = STBRP_HEURISTIC_Skyline_default,
+   STBRP_HEURISTIC_Skyline_BF_sortHeight
+};
+
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// the details of the following structures don't matter to you, but they must
+// be visible so you can handle the memory allocations for them
+
+struct stbrp_node
+{
+   stbrp_coord  x,y;
+   stbrp_node  *next;
+};
+
+struct stbrp_context
+{
+   int width;
+   int height;
+   int align;
+   int init_mode;
+   int heuristic;
+   int num_nodes;
+   stbrp_node *active_head;
+   stbrp_node *free_head;
+   stbrp_node extra[2]; // we allocate two extra nodes so optimal user-node-count is 'width' not 'width+2'
+};
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+
+//////////////////////////////////////////////////////////////////////////////
+//
+//     IMPLEMENTATION SECTION
+//
+
+#ifdef STB_RECT_PACK_IMPLEMENTATION
+#ifndef STBRP_SORT
+#include <stdlib.h>
+#define STBRP_SORT qsort
+#endif
+
+#ifndef STBRP_ASSERT
+#include <assert.h>
+#define STBRP_ASSERT assert
+#endif
+
+// [DEAR IMGUI] Added STBRP__CDECL
+#ifdef _MSC_VER
+#define STBRP__NOTUSED(v)  (void)(v)
+#define STBRP__CDECL __cdecl
+#else
+#define STBRP__NOTUSED(v)  (void)sizeof(v)
+#define STBRP__CDECL
+#endif
+
+enum
+{
+   STBRP__INIT_skyline = 1
+};
+
+STBRP_DEF void stbrp_setup_heuristic(stbrp_context *context, int heuristic)
+{
+   switch (context->init_mode) {
+      case STBRP__INIT_skyline:
+         STBRP_ASSERT(heuristic == STBRP_HEURISTIC_Skyline_BL_sortHeight || heuristic == STBRP_HEURISTIC_Skyline_BF_sortHeight);
+         context->heuristic = heuristic;
+         break;
+      default:
+         STBRP_ASSERT(0);
+   }
+}
+
+STBRP_DEF void stbrp_setup_allow_out_of_mem(stbrp_context *context, int allow_out_of_mem)
+{
+   if (allow_out_of_mem)
+      // if it's ok to run out of memory, then don't bother aligning them;
+      // this gives better packing, but may fail due to OOM (even though
+      // the rectangles easily fit). @TODO a smarter approach would be to only
+      // quantize once we've hit OOM, then we could get rid of this parameter.
+      context->align = 1;
+   else {
+      // if it's not ok to run out of memory, then quantize the widths
+      // so that num_nodes is always enough nodes.
+      //
+      // I.e. num_nodes * align >= width
+      //                  align >= width / num_nodes
+      //                  align = ceil(width/num_nodes)
+
+      context->align = (context->width + context->num_nodes-1) / context->num_nodes;
+   }
+}
+
+STBRP_DEF void stbrp_init_target(stbrp_context *context, int width, int height, stbrp_node *nodes, int num_nodes)
+{
+   int i;
+#ifndef STBRP_LARGE_RECTS
+   STBRP_ASSERT(width <= 0xffff && height <= 0xffff);
+#endif
+
+   for (i=0; i < num_nodes-1; ++i)
+      nodes[i].next = &nodes[i+1];
+   nodes[i].next = NULL;
+   context->init_mode = STBRP__INIT_skyline;
+   context->heuristic = STBRP_HEURISTIC_Skyline_default;
+   context->free_head = &nodes[0];
+   context->active_head = &context->extra[0];
+   context->width = width;
+   context->height = height;
+   context->num_nodes = num_nodes;
+   stbrp_setup_allow_out_of_mem(context, 0);
+
+   // node 0 is the full width, node 1 is the sentinel (lets us not store width explicitly)
+   context->extra[0].x = 0;
+   context->extra[0].y = 0;
+   context->extra[0].next = &context->extra[1];
+   context->extra[1].x = (stbrp_coord) width;
+#ifdef STBRP_LARGE_RECTS
+   context->extra[1].y = (1<<30);
+#else
+   context->extra[1].y = 65535;
+#endif
+   context->extra[1].next = NULL;
+}
+
+// find minimum y position if it starts at x1
+static int stbrp__skyline_find_min_y(stbrp_context *c, stbrp_node *first, int x0, int width, int *pwaste)
+{
+   stbrp_node *node = first;
+   int x1 = x0 + width;
+   int min_y, visited_width, waste_area;
+
+   STBRP__NOTUSED(c);
+
+   STBRP_ASSERT(first->x <= x0);
+
+   #if 0
+   // skip in case we're past the node
+   while (node->next->x <= x0)
+      ++node;
+   #else
+   STBRP_ASSERT(node->next->x > x0); // we ended up handling this in the caller for efficiency
+   #endif
+
+   STBRP_ASSERT(node->x <= x0);
+
+   min_y = 0;
+   waste_area = 0;
+   visited_width = 0;
+   while (node->x < x1) {
+      if (node->y > min_y) {
+         // raise min_y higher.
+         // we've accounted for all waste up to min_y,
+         // but we'll now add more waste for everything we've visted
+         waste_area += visited_width * (node->y - min_y);
+         min_y = node->y;
+         // the first time through, visited_width might be reduced
+         if (node->x < x0)
+            visited_width += node->next->x - x0;
+         else
+            visited_width += node->next->x - node->x;
+      } else {
+         // add waste area
+         int under_width = node->next->x - node->x;
+         if (under_width + visited_width > width)
+            under_width = width - visited_width;
+         waste_area += under_width * (min_y - node->y);
+         visited_width += under_width;
+      }
+      node = node->next;
+   }
+
+   *pwaste = waste_area;
+   return min_y;
+}
+
+typedef struct
+{
+   int x,y;
+   stbrp_node **prev_link;
+} stbrp__findresult;
+
+static stbrp__findresult stbrp__skyline_find_best_pos(stbrp_context *c, int width, int height)
+{
+   int best_waste = (1<<30), best_x, best_y = (1 << 30);
+   stbrp__findresult fr;
+   stbrp_node **prev, *node, *tail, **best = NULL;
+
+   // align to multiple of c->align
+   width = (width + c->align - 1);
+   width -= width % c->align;
+   STBRP_ASSERT(width % c->align == 0);
+
+   // if it can't possibly fit, bail immediately
+   if (width > c->width || height > c->height) {
+      fr.prev_link = NULL;
+      fr.x = fr.y = 0;
+      return fr;
+   }
+
+   node = c->active_head;
+   prev = &c->active_head;
+   while (node->x + width <= c->width) {
+      int y,waste;
+      y = stbrp__skyline_find_min_y(c, node, node->x, width, &waste);
+      if (c->heuristic == STBRP_HEURISTIC_Skyline_BL_sortHeight) { // actually just want to test BL
+         // bottom left
+         if (y < best_y) {
+            best_y = y;
+            best = prev;
+         }
+      } else {
+         // best-fit
+         if (y + height <= c->height) {
+            // can only use it if it first vertically
+            if (y < best_y || (y == best_y && waste < best_waste)) {
+               best_y = y;
+               best_waste = waste;
+               best = prev;
+            }
+         }
+      }
+      prev = &node->next;
+      node = node->next;
+   }
+
+   best_x = (best == NULL) ? 0 : (*best)->x;
+
+   // if doing best-fit (BF), we also have to try aligning right edge to each node position
+   //
+   // e.g, if fitting
+   //
+   //     ____________________
+   //    |____________________|
+   //
+   //            into
+   //
+   //   |                         |
+   //   |             ____________|
+   //   |____________|
+   //
+   // then right-aligned reduces waste, but bottom-left BL is always chooses left-aligned
+   //
+   // This makes BF take about 2x the time
+
+   if (c->heuristic == STBRP_HEURISTIC_Skyline_BF_sortHeight) {
+      tail = c->active_head;
+      node = c->active_head;
+      prev = &c->active_head;
+      // find first node that's admissible
+      while (tail->x < width)
+         tail = tail->next;
+      while (tail) {
+         int xpos = tail->x - width;
+         int y,waste;
+         STBRP_ASSERT(xpos >= 0);
+         // find the left position that matches this
+         while (node->next->x <= xpos) {
+            prev = &node->next;
+            node = node->next;
+         }
+         STBRP_ASSERT(node->next->x > xpos && node->x <= xpos);
+         y = stbrp__skyline_find_min_y(c, node, xpos, width, &waste);
+         if (y + height <= c->height) {
+            if (y <= best_y) {
+               if (y < best_y || waste < best_waste || (waste==best_waste && xpos < best_x)) {
+                  best_x = xpos;
+                  STBRP_ASSERT(y <= best_y);
+                  best_y = y;
+                  best_waste = waste;
+                  best = prev;
+               }
+            }
+         }
+         tail = tail->next;
+      }         
+   }
+
+   fr.prev_link = best;
+   fr.x = best_x;
+   fr.y = best_y;
+   return fr;
+}
+
+static stbrp__findresult stbrp__skyline_pack_rectangle(stbrp_context *context, int width, int height)
+{
+   // find best position according to heuristic
+   stbrp__findresult res = stbrp__skyline_find_best_pos(context, width, height);
+   stbrp_node *node, *cur;
+
+   // bail if:
+   //    1. it failed
+   //    2. the best node doesn't fit (we don't always check this)
+   //    3. we're out of memory
+   if (res.prev_link == NULL || res.y + height > context->height || context->free_head == NULL) {
+      res.prev_link = NULL;
+      return res;
+   }
+
+   // on success, create new node
+   node = context->free_head;
+   node->x = (stbrp_coord) res.x;
+   node->y = (stbrp_coord) (res.y + height);
+
+   context->free_head = node->next;
+
+   // insert the new node into the right starting point, and
+   // let 'cur' point to the remaining nodes needing to be
+   // stiched back in
+
+   cur = *res.prev_link;
+   if (cur->x < res.x) {
+      // preserve the existing one, so start testing with the next one
+      stbrp_node *next = cur->next;
+      cur->next = node;
+      cur = next;
+   } else {
+      *res.prev_link = node;
+   }
+
+   // from here, traverse cur and free the nodes, until we get to one
+   // that shouldn't be freed
+   while (cur->next && cur->next->x <= res.x + width) {
+      stbrp_node *next = cur->next;
+      // move the current node to the free list
+      cur->next = context->free_head;
+      context->free_head = cur;
+      cur = next;
+   }
+
+   // stitch the list back in
+   node->next = cur;
+
+   if (cur->x < res.x + width)
+      cur->x = (stbrp_coord) (res.x + width);
+
+#ifdef _DEBUG
+   cur = context->active_head;
+   while (cur->x < context->width) {
+      STBRP_ASSERT(cur->x < cur->next->x);
+      cur = cur->next;
+   }
+   STBRP_ASSERT(cur->next == NULL);
+
+   {
+      int count=0;
+      cur = context->active_head;
+      while (cur) {
+         cur = cur->next;
+         ++count;
+      }
+      cur = context->free_head;
+      while (cur) {
+         cur = cur->next;
+         ++count;
+      }
+      STBRP_ASSERT(count == context->num_nodes+2);
+   }
+#endif
+
+   return res;
+}
+
+// [DEAR IMGUI] Added STBRP__CDECL
+static int STBRP__CDECL rect_height_compare(const void *a, const void *b)
+{
+   const stbrp_rect *p = (const stbrp_rect *) a;
+   const stbrp_rect *q = (const stbrp_rect *) b;
+   if (p->h > q->h)
+      return -1;
+   if (p->h < q->h)
+      return  1;
+   return (p->w > q->w) ? -1 : (p->w < q->w);
+}
+
+// [DEAR IMGUI] Added STBRP__CDECL
+static int STBRP__CDECL rect_original_order(const void *a, const void *b)
+{
+   const stbrp_rect *p = (const stbrp_rect *) a;
+   const stbrp_rect *q = (const stbrp_rect *) b;
+   return (p->was_packed < q->was_packed) ? -1 : (p->was_packed > q->was_packed);
+}
+
+#ifdef STBRP_LARGE_RECTS
+#define STBRP__MAXVAL  0xffffffff
+#else
+#define STBRP__MAXVAL  0xffff
+#endif
+
+STBRP_DEF int stbrp_pack_rects(stbrp_context *context, stbrp_rect *rects, int num_rects)
+{
+   int i, all_rects_packed = 1;
+
+   // we use the 'was_packed' field internally to allow sorting/unsorting
+   for (i=0; i < num_rects; ++i) {
+      rects[i].was_packed = i;
+   }
+
+   // sort according to heuristic
+   STBRP_SORT(rects, num_rects, sizeof(rects[0]), rect_height_compare);
+
+   for (i=0; i < num_rects; ++i) {
+      if (rects[i].w == 0 || rects[i].h == 0) {
+         rects[i].x = rects[i].y = 0;  // empty rect needs no space
+      } else {
+         stbrp__findresult fr = stbrp__skyline_pack_rectangle(context, rects[i].w, rects[i].h);
+         if (fr.prev_link) {
+            rects[i].x = (stbrp_coord) fr.x;
+            rects[i].y = (stbrp_coord) fr.y;
+         } else {
+            rects[i].x = rects[i].y = STBRP__MAXVAL;
+         }
+      }
+   }
+
+   // unsort
+   STBRP_SORT(rects, num_rects, sizeof(rects[0]), rect_original_order);
+
+   // set was_packed flags and all_rects_packed status
+   for (i=0; i < num_rects; ++i) {
+      rects[i].was_packed = !(rects[i].x == STBRP__MAXVAL && rects[i].y == STBRP__MAXVAL);
+      if (!rects[i].was_packed)
+         all_rects_packed = 0;
+   }
+
+   // return the all_rects_packed status
+   return all_rects_packed;
+}
+#endif
+
+/*
+------------------------------------------------------------------------------
+This software is available under 2 licenses -- choose whichever you prefer.
+------------------------------------------------------------------------------
+ALTERNATIVE A - MIT License
+Copyright (c) 2017 Sean Barrett
+Permission is hereby granted, free of charge, to any person obtaining a copy of 
+this software and associated documentation files (the "Software"), to deal in 
+the Software without restriction, including without limitation the rights to 
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies 
+of the Software, and to permit persons to whom the Software is furnished to do 
+so, subject to the following conditions:
+The above copyright notice and this permission notice shall be included in all 
+copies or substantial portions of the Software.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 
+SOFTWARE.
+------------------------------------------------------------------------------
+ALTERNATIVE B - Public Domain (www.unlicense.org)
+This is free and unencumbered software released into the public domain.
+Anyone is free to copy, modify, publish, use, compile, sell, or distribute this 
+software, either in source code form or as a compiled binary, for any purpose, 
+commercial or non-commercial, and by any means.
+In jurisdictions that recognize copyright laws, the author or authors of this 
+software dedicate any and all copyright interest in the software to the public 
+domain. We make this dedication for the benefit of the public at large and to 
+the detriment of our heirs and successors. We intend this dedication to be an 
+overt act of relinquishment in perpetuity of all present and future rights to 
+this software under copyright law.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
+AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 
+ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+------------------------------------------------------------------------------
+*/

include/imgui/imstb_textedit.h

+// [DEAR IMGUI]
+// This is a slightly modified version of stb_textedit.h 1.13. 
+// Those changes would need to be pushed into nothings/stb:
+// - Fix in stb_textedit_discard_redo (see https://github.com/nothings/stb/issues/321)
+// Grep for [DEAR IMGUI] to find the changes.
+
+// stb_textedit.h - v1.13  - public domain - Sean Barrett
+// Development of this library was sponsored by RAD Game Tools
+//
+// This C header file implements the guts of a multi-line text-editing
+// widget; you implement display, word-wrapping, and low-level string
+// insertion/deletion, and stb_textedit will map user inputs into
+// insertions & deletions, plus updates to the cursor position,
+// selection state, and undo state.
+//
+// It is intended for use in games and other systems that need to build
+// their own custom widgets and which do not have heavy text-editing
+// requirements (this library is not recommended for use for editing large
+// texts, as its performance does not scale and it has limited undo).
+//
+// Non-trivial behaviors are modelled after Windows text controls.
+// 
+//
+// LICENSE
+//
+// See end of file for license information.
+//
+//
+// DEPENDENCIES
+//
+// Uses the C runtime function 'memmove', which you can override
+// by defining STB_TEXTEDIT_memmove before the implementation.
+// Uses no other functions. Performs no runtime allocations.
+//
+//
+// VERSION HISTORY
+//
+//   1.13 (2019-02-07) fix bug in undo size management
+//   1.12 (2018-01-29) user can change STB_TEXTEDIT_KEYTYPE, fix redo to avoid crash
+//   1.11 (2017-03-03) fix HOME on last line, dragging off single-line textfield
+//   1.10 (2016-10-25) supress warnings about casting away const with -Wcast-qual
+//   1.9  (2016-08-27) customizable move-by-word
+//   1.8  (2016-04-02) better keyboard handling when mouse button is down
+//   1.7  (2015-09-13) change y range handling in case baseline is non-0
+//   1.6  (2015-04-15) allow STB_TEXTEDIT_memmove
+//   1.5  (2014-09-10) add support for secondary keys for OS X
+//   1.4  (2014-08-17) fix signed/unsigned warnings
+//   1.3  (2014-06-19) fix mouse clicking to round to nearest char boundary
+//   1.2  (2014-05-27) fix some RAD types that had crept into the new code
+//   1.1  (2013-12-15) move-by-word (requires STB_TEXTEDIT_IS_SPACE )
+//   1.0  (2012-07-26) improve documentation, initial public release
+//   0.3  (2012-02-24) bugfixes, single-line mode; insert mode
+//   0.2  (2011-11-28) fixes to undo/redo
+//   0.1  (2010-07-08) initial version
+//
+// ADDITIONAL CONTRIBUTORS
+//
+//   Ulf Winklemann: move-by-word in 1.1
+//   Fabian Giesen: secondary key inputs in 1.5
+//   Martins Mozeiko: STB_TEXTEDIT_memmove in 1.6
+//
+//   Bugfixes:
+//      Scott Graham
+//      Daniel Keller
+//      Omar Cornut
+//      Dan Thompson
+//
+// USAGE
+//
+// This file behaves differently depending on what symbols you define
+// before including it.
+//
+//
+// Header-file mode:
+//
+//   If you do not define STB_TEXTEDIT_IMPLEMENTATION before including this,
+//   it will operate in "header file" mode. In this mode, it declares a
+//   single public symbol, STB_TexteditState, which encapsulates the current
+//   state of a text widget (except for the string, which you will store
+//   separately).
+//
+//   To compile in this mode, you must define STB_TEXTEDIT_CHARTYPE to a
+//   primitive type that defines a single character (e.g. char, wchar_t, etc).
+//
+//   To save space or increase undo-ability, you can optionally define the
+//   following things that are used by the undo system:
+//
+//      STB_TEXTEDIT_POSITIONTYPE         small int type encoding a valid cursor position
+//      STB_TEXTEDIT_UNDOSTATECOUNT       the number of undo states to allow
+//      STB_TEXTEDIT_UNDOCHARCOUNT        the number of characters to store in the undo buffer
+//
+//   If you don't define these, they are set to permissive types and
+//   moderate sizes. The undo system does no memory allocations, so
+//   it grows STB_TexteditState by the worst-case storage which is (in bytes):
+//
+//        [4 + 3 * sizeof(STB_TEXTEDIT_POSITIONTYPE)] * STB_TEXTEDIT_UNDOSTATE_COUNT
+//      +          sizeof(STB_TEXTEDIT_CHARTYPE)      * STB_TEXTEDIT_UNDOCHAR_COUNT
+//
+//
+// Implementation mode:
+//
+//   If you define STB_TEXTEDIT_IMPLEMENTATION before including this, it
+//   will compile the implementation of the text edit widget, depending
+//   on a large number of symbols which must be defined before the include.
+//
+//   The implementation is defined only as static functions. You will then
+//   need to provide your own APIs in the same file which will access the
+//   static functions.
+//
+//   The basic concept is that you provide a "string" object which
+//   behaves like an array of characters. stb_textedit uses indices to
+//   refer to positions in the string, implicitly representing positions
+//   in the displayed textedit. This is true for both plain text and
+//   rich text; even with rich text stb_truetype interacts with your
+//   code as if there was an array of all the displayed characters.
+//
+// Symbols that must be the same in header-file and implementation mode:
+//
+//     STB_TEXTEDIT_CHARTYPE             the character type
+//     STB_TEXTEDIT_POSITIONTYPE         small type that is a valid cursor position
+//     STB_TEXTEDIT_UNDOSTATECOUNT       the number of undo states to allow
+//     STB_TEXTEDIT_UNDOCHARCOUNT        the number of characters to store in the undo buffer
+//
+// Symbols you must define for implementation mode:
+//
+//    STB_TEXTEDIT_STRING               the type of object representing a string being edited,
+//                                      typically this is a wrapper object with other data you need
+//
+//    STB_TEXTEDIT_STRINGLEN(obj)       the length of the string (ideally O(1))
+//    STB_TEXTEDIT_LAYOUTROW(&r,obj,n)  returns the results of laying out a line of characters
+//                                        starting from character #n (see discussion below)
+//    STB_TEXTEDIT_GETWIDTH(obj,n,i)    returns the pixel delta from the xpos of the i'th character
+//                                        to the xpos of the i+1'th char for a line of characters
+//                                        starting at character #n (i.e. accounts for kerning
+//                                        with previous char)
+//    STB_TEXTEDIT_KEYTOTEXT(k)         maps a keyboard input to an insertable character
+//                                        (return type is int, -1 means not valid to insert)
+//    STB_TEXTEDIT_GETCHAR(obj,i)       returns the i'th character of obj, 0-based
+//    STB_TEXTEDIT_NEWLINE              the character returned by _GETCHAR() we recognize
+//                                        as manually wordwrapping for end-of-line positioning
+//
+//    STB_TEXTEDIT_DELETECHARS(obj,i,n)      delete n characters starting at i
+//    STB_TEXTEDIT_INSERTCHARS(obj,i,c*,n)   insert n characters at i (pointed to by STB_TEXTEDIT_CHARTYPE*)
+//
+//    STB_TEXTEDIT_K_SHIFT       a power of two that is or'd in to a keyboard input to represent the shift key
+//
+//    STB_TEXTEDIT_K_LEFT        keyboard input to move cursor left
+//    STB_TEXTEDIT_K_RIGHT       keyboard input to move cursor right
+//    STB_TEXTEDIT_K_UP          keyboard input to move cursor up
+//    STB_TEXTEDIT_K_DOWN        keyboard input to move cursor down
+//    STB_TEXTEDIT_K_LINESTART   keyboard input to move cursor to start of line  // e.g. HOME
+//    STB_TEXTEDIT_K_LINEEND     keyboard input to move cursor to end of line    // e.g. END
+//    STB_TEXTEDIT_K_TEXTSTART   keyboard input to move cursor to start of text  // e.g. ctrl-HOME
+//    STB_TEXTEDIT_K_TEXTEND     keyboard input to move cursor to end of text    // e.g. ctrl-END
+//    STB_TEXTEDIT_K_DELETE      keyboard input to delete selection or character under cursor
+//    STB_TEXTEDIT_K_BACKSPACE   keyboard input to delete selection or character left of cursor
+//    STB_TEXTEDIT_K_UNDO        keyboard input to perform undo
+//    STB_TEXTEDIT_K_REDO        keyboard input to perform redo
+//
+// Optional:
+//    STB_TEXTEDIT_K_INSERT              keyboard input to toggle insert mode
+//    STB_TEXTEDIT_IS_SPACE(ch)          true if character is whitespace (e.g. 'isspace'),
+//                                          required for default WORDLEFT/WORDRIGHT handlers
+//    STB_TEXTEDIT_MOVEWORDLEFT(obj,i)   custom handler for WORDLEFT, returns index to move cursor to
+//    STB_TEXTEDIT_MOVEWORDRIGHT(obj,i)  custom handler for WORDRIGHT, returns index to move cursor to
+//    STB_TEXTEDIT_K_WORDLEFT            keyboard input to move cursor left one word // e.g. ctrl-LEFT
+//    STB_TEXTEDIT_K_WORDRIGHT           keyboard input to move cursor right one word // e.g. ctrl-RIGHT
+//    STB_TEXTEDIT_K_LINESTART2          secondary keyboard input to move cursor to start of line
+//    STB_TEXTEDIT_K_LINEEND2            secondary keyboard input to move cursor to end of line
+//    STB_TEXTEDIT_K_TEXTSTART2          secondary keyboard input to move cursor to start of text
+//    STB_TEXTEDIT_K_TEXTEND2            secondary keyboard input to move cursor to end of text
+//
+// Todo:
+//    STB_TEXTEDIT_K_PGUP        keyboard input to move cursor up a page
+//    STB_TEXTEDIT_K_PGDOWN      keyboard input to move cursor down a page
+//
+// Keyboard input must be encoded as a single integer value; e.g. a character code
+// and some bitflags that represent shift states. to simplify the interface, SHIFT must
+// be a bitflag, so we can test the shifted state of cursor movements to allow selection,
+// i.e. (STB_TEXTED_K_RIGHT|STB_TEXTEDIT_K_SHIFT) should be shifted right-arrow.
+//
+// You can encode other things, such as CONTROL or ALT, in additional bits, and
+// then test for their presence in e.g. STB_TEXTEDIT_K_WORDLEFT. For example,
+// my Windows implementations add an additional CONTROL bit, and an additional KEYDOWN
+// bit. Then all of the STB_TEXTEDIT_K_ values bitwise-or in the KEYDOWN bit,
+// and I pass both WM_KEYDOWN and WM_CHAR events to the "key" function in the
+// API below. The control keys will only match WM_KEYDOWN events because of the
+// keydown bit I add, and STB_TEXTEDIT_KEYTOTEXT only tests for the KEYDOWN
+// bit so it only decodes WM_CHAR events.
+//
+// STB_TEXTEDIT_LAYOUTROW returns information about the shape of one displayed
+// row of characters assuming they start on the i'th character--the width and
+// the height and the number of characters consumed. This allows this library
+// to traverse the entire layout incrementally. You need to compute word-wrapping
+// here.
+//
+// Each textfield keeps its own insert mode state, which is not how normal
+// applications work. To keep an app-wide insert mode, update/copy the
+// "insert_mode" field of STB_TexteditState before/after calling API functions.
+//
+// API
+//
+//    void stb_textedit_initialize_state(STB_TexteditState *state, int is_single_line)
+//
+//    void stb_textedit_click(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, float x, float y)
+//    void stb_textedit_drag(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, float x, float y)
+//    int  stb_textedit_cut(STB_TEXTEDIT_STRING *str, STB_TexteditState *state)
+//    int  stb_textedit_paste(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, STB_TEXTEDIT_CHARTYPE *text, int len)
+//    void stb_textedit_key(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, STB_TEXEDIT_KEYTYPE key)
+//
+//    Each of these functions potentially updates the string and updates the
+//    state.
+//
+//      initialize_state:
+//          set the textedit state to a known good default state when initially
+//          constructing the textedit.
+//
+//      click:
+//          call this with the mouse x,y on a mouse down; it will update the cursor
+//          and reset the selection start/end to the cursor point. the x,y must
+//          be relative to the text widget, with (0,0) being the top left.
+//     
+//      drag:
+//          call this with the mouse x,y on a mouse drag/up; it will update the
+//          cursor and the selection end point
+//     
+//      cut:
+//          call this to delete the current selection; returns true if there was
+//          one. you should FIRST copy the current selection to the system paste buffer.
+//          (To copy, just copy the current selection out of the string yourself.)
+//     
+//      paste:
+//          call this to paste text at the current cursor point or over the current
+//          selection if there is one.
+//     
+//      key:
+//          call this for keyboard inputs sent to the textfield. you can use it
+//          for "key down" events or for "translated" key events. if you need to
+//          do both (as in Win32), or distinguish Unicode characters from control
+//          inputs, set a high bit to distinguish the two; then you can define the
+//          various definitions like STB_TEXTEDIT_K_LEFT have the is-key-event bit
+//          set, and make STB_TEXTEDIT_KEYTOCHAR check that the is-key-event bit is
+//          clear. STB_TEXTEDIT_KEYTYPE defaults to int, but you can #define it to
+//          anything other type you wante before including.
+//
+//     
+//   When rendering, you can read the cursor position and selection state from
+//   the STB_TexteditState.
+//
+//
+// Notes:
+//
+// This is designed to be usable in IMGUI, so it allows for the possibility of
+// running in an IMGUI that has NOT cached the multi-line layout. For this
+// reason, it provides an interface that is compatible with computing the
+// layout incrementally--we try to make sure we make as few passes through
+// as possible. (For example, to locate the mouse pointer in the text, we
+// could define functions that return the X and Y positions of characters
+// and binary search Y and then X, but if we're doing dynamic layout this
+// will run the layout algorithm many times, so instead we manually search
+// forward in one pass. Similar logic applies to e.g. up-arrow and
+// down-arrow movement.)
+//
+// If it's run in a widget that *has* cached the layout, then this is less
+// efficient, but it's not horrible on modern computers. But you wouldn't
+// want to edit million-line files with it.
+
+
+////////////////////////////////////////////////////////////////////////////
+////////////////////////////////////////////////////////////////////////////
+////
+////   Header-file mode
+////
+////
+
+#ifndef INCLUDE_STB_TEXTEDIT_H
+#define INCLUDE_STB_TEXTEDIT_H
+
+////////////////////////////////////////////////////////////////////////
+//
+//     STB_TexteditState
+//
+// Definition of STB_TexteditState which you should store
+// per-textfield; it includes cursor position, selection state,
+// and undo state.
+//
+
+#ifndef STB_TEXTEDIT_UNDOSTATECOUNT
+#define STB_TEXTEDIT_UNDOSTATECOUNT   99
+#endif
+#ifndef STB_TEXTEDIT_UNDOCHARCOUNT
+#define STB_TEXTEDIT_UNDOCHARCOUNT   999
+#endif
+#ifndef STB_TEXTEDIT_CHARTYPE
+#define STB_TEXTEDIT_CHARTYPE        int
+#endif
+#ifndef STB_TEXTEDIT_POSITIONTYPE
+#define STB_TEXTEDIT_POSITIONTYPE    int
+#endif
+
+typedef struct
+{
+   // private data
+   STB_TEXTEDIT_POSITIONTYPE  where;
+   STB_TEXTEDIT_POSITIONTYPE  insert_length;
+   STB_TEXTEDIT_POSITIONTYPE  delete_length;
+   int                        char_storage;
+} StbUndoRecord;
+
+typedef struct
+{
+   // private data
+   StbUndoRecord          undo_rec [STB_TEXTEDIT_UNDOSTATECOUNT];
+   STB_TEXTEDIT_CHARTYPE  undo_char[STB_TEXTEDIT_UNDOCHARCOUNT];
+   short undo_point, redo_point;
+   int undo_char_point, redo_char_point;
+} StbUndoState;
+
+typedef struct
+{
+   /////////////////////
+   //
+   // public data
+   //
+
+   int cursor;
+   // position of the text cursor within the string
+
+   int select_start;          // selection start point
+   int select_end;
+   // selection start and end point in characters; if equal, no selection.
+   // note that start may be less than or greater than end (e.g. when
+   // dragging the mouse, start is where the initial click was, and you
+   // can drag in either direction)
+
+   unsigned char insert_mode;
+   // each textfield keeps its own insert mode state. to keep an app-wide
+   // insert mode, copy this value in/out of the app state
+
+   /////////////////////
+   //
+   // private data
+   //
+   unsigned char cursor_at_end_of_line; // not implemented yet
+   unsigned char initialized;
+   unsigned char has_preferred_x;
+   unsigned char single_line;
+   unsigned char padding1, padding2, padding3;
+   float preferred_x; // this determines where the cursor up/down tries to seek to along x
+   StbUndoState undostate;
+} STB_TexteditState;
+
+
+////////////////////////////////////////////////////////////////////////
+//
+//     StbTexteditRow
+//
+// Result of layout query, used by stb_textedit to determine where
+// the text in each row is.
+
+// result of layout query
+typedef struct
+{
+   float x0,x1;             // starting x location, end x location (allows for align=right, etc)
+   float baseline_y_delta;  // position of baseline relative to previous row's baseline
+   float ymin,ymax;         // height of row above and below baseline
+   int num_chars;
+} StbTexteditRow;
+#endif //INCLUDE_STB_TEXTEDIT_H
+
+
+////////////////////////////////////////////////////////////////////////////
+////////////////////////////////////////////////////////////////////////////
+////
+////   Implementation mode
+////
+////
+
+
+// implementation isn't include-guarded, since it might have indirectly
+// included just the "header" portion
+#ifdef STB_TEXTEDIT_IMPLEMENTATION
+
+#ifndef STB_TEXTEDIT_memmove
+#include <string.h>
+#define STB_TEXTEDIT_memmove memmove
+#endif
+
+
+/////////////////////////////////////////////////////////////////////////////
+//
+//      Mouse input handling
+//
+
+// traverse the layout to locate the nearest character to a display position
+static int stb_text_locate_coord(STB_TEXTEDIT_STRING *str, float x, float y)
+{
+   StbTexteditRow r;
+   int n = STB_TEXTEDIT_STRINGLEN(str);
+   float base_y = 0, prev_x;
+   int i=0, k;
+
+   r.x0 = r.x1 = 0;
+   r.ymin = r.ymax = 0;
+   r.num_chars = 0;
+
+   // search rows to find one that straddles 'y'
+   while (i < n) {
+      STB_TEXTEDIT_LAYOUTROW(&r, str, i);
+      if (r.num_chars <= 0)
+         return n;
+
+      if (i==0 && y < base_y + r.ymin)
+         return 0;
+
+      if (y < base_y + r.ymax)
+         break;
+
+      i += r.num_chars;
+      base_y += r.baseline_y_delta;
+   }
+
+   // below all text, return 'after' last character
+   if (i >= n)
+      return n;
+
+   // check if it's before the beginning of the line
+   if (x < r.x0)
+      return i;
+
+   // check if it's before the end of the line
+   if (x < r.x1) {
+      // search characters in row for one that straddles 'x'
+      prev_x = r.x0;
+      for (k=0; k < r.num_chars; ++k) {
+         float w = STB_TEXTEDIT_GETWIDTH(str, i, k);
+         if (x < prev_x+w) {
+            if (x < prev_x+w/2)
+               return k+i;
+            else
+               return k+i+1;
+         }
+         prev_x += w;
+      }
+      // shouldn't happen, but if it does, fall through to end-of-line case
+   }
+
+   // if the last character is a newline, return that. otherwise return 'after' the last character
+   if (STB_TEXTEDIT_GETCHAR(str, i+r.num_chars-1) == STB_TEXTEDIT_NEWLINE)
+      return i+r.num_chars-1;
+   else
+      return i+r.num_chars;
+}
+
+// API click: on mouse down, move the cursor to the clicked location, and reset the selection
+static void stb_textedit_click(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, float x, float y)
+{
+   // In single-line mode, just always make y = 0. This lets the drag keep working if the mouse
+   // goes off the top or bottom of the text
+   if( state->single_line )
+   {
+      StbTexteditRow r;
+      STB_TEXTEDIT_LAYOUTROW(&r, str, 0);
+      y = r.ymin;
+   }
+
+   state->cursor = stb_text_locate_coord(str, x, y);
+   state->select_start = state->cursor;
+   state->select_end = state->cursor;
+   state->has_preferred_x = 0;
+}
+
+// API drag: on mouse drag, move the cursor and selection endpoint to the clicked location
+static void stb_textedit_drag(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, float x, float y)
+{
+   int p = 0;
+
+   // In single-line mode, just always make y = 0. This lets the drag keep working if the mouse
+   // goes off the top or bottom of the text
+   if( state->single_line )
+   {
+      StbTexteditRow r;
+      STB_TEXTEDIT_LAYOUTROW(&r, str, 0);
+      y = r.ymin;
+   }
+
+   if (state->select_start == state->select_end)
+      state->select_start = state->cursor;
+
+   p = stb_text_locate_coord(str, x, y);
+   state->cursor = state->select_end = p;
+}
+
+/////////////////////////////////////////////////////////////////////////////
+//
+//      Keyboard input handling
+//
+
+// forward declarations
+static void stb_text_undo(STB_TEXTEDIT_STRING *str, STB_TexteditState *state);
+static void stb_text_redo(STB_TEXTEDIT_STRING *str, STB_TexteditState *state);
+static void stb_text_makeundo_delete(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, int where, int length);
+static void stb_text_makeundo_insert(STB_TexteditState *state, int where, int length);
+static void stb_text_makeundo_replace(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, int where, int old_length, int new_length);
+
+typedef struct
+{
+   float x,y;    // position of n'th character
+   float height; // height of line
+   int first_char, length; // first char of row, and length
+   int prev_first;  // first char of previous row
+} StbFindState;
+
+// find the x/y location of a character, and remember info about the previous row in
+// case we get a move-up event (for page up, we'll have to rescan)
+static void stb_textedit_find_charpos(StbFindState *find, STB_TEXTEDIT_STRING *str, int n, int single_line)
+{
+   StbTexteditRow r;
+   int prev_start = 0;
+   int z = STB_TEXTEDIT_STRINGLEN(str);
+   int i=0, first;
+
+   if (n == z) {
+      // if it's at the end, then find the last line -- simpler than trying to
+      // explicitly handle this case in the regular code
+      if (single_line) {
+         STB_TEXTEDIT_LAYOUTROW(&r, str, 0);
+         find->y = 0;
+         find->first_char = 0;
+         find->length = z;
+         find->height = r.ymax - r.ymin;
+         find->x = r.x1;
+      } else {
+         find->y = 0;
+         find->x = 0;
+         find->height = 1;
+         while (i < z) {
+            STB_TEXTEDIT_LAYOUTROW(&r, str, i);
+            prev_start = i;
+            i += r.num_chars;
+         }
+         find->first_char = i;
+         find->length = 0;
+         find->prev_first = prev_start;
+      }
+      return;
+   }
+
+   // search rows to find the one that straddles character n
+   find->y = 0;
+
+   for(;;) {
+      STB_TEXTEDIT_LAYOUTROW(&r, str, i);
+      if (n < i + r.num_chars)
+         break;
+      prev_start = i;
+      i += r.num_chars;
+      find->y += r.baseline_y_delta;
+   }
+
+   find->first_char = first = i;
+   find->length = r.num_chars;
+   find->height = r.ymax - r.ymin;
+   find->prev_first = prev_start;
+
+   // now scan to find xpos
+   find->x = r.x0;
+   for (i=0; first+i < n; ++i)
+      find->x += STB_TEXTEDIT_GETWIDTH(str, first, i);
+}
+
+#define STB_TEXT_HAS_SELECTION(s)   ((s)->select_start != (s)->select_end)
+
+// make the selection/cursor state valid if client altered the string
+static void stb_textedit_clamp(STB_TEXTEDIT_STRING *str, STB_TexteditState *state)
+{
+   int n = STB_TEXTEDIT_STRINGLEN(str);
+   if (STB_TEXT_HAS_SELECTION(state)) {
+      if (state->select_start > n) state->select_start = n;
+      if (state->select_end   > n) state->select_end = n;
+      // if clamping forced them to be equal, move the cursor to match
+      if (state->select_start == state->select_end)
+         state->cursor = state->select_start;
+   }
+   if (state->cursor > n) state->cursor = n;
+}
+
+// delete characters while updating undo
+static void stb_textedit_delete(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, int where, int len)
+{
+   stb_text_makeundo_delete(str, state, where, len);
+   STB_TEXTEDIT_DELETECHARS(str, where, len);
+   state->has_preferred_x = 0;
+}
+
+// delete the section
+static void stb_textedit_delete_selection(STB_TEXTEDIT_STRING *str, STB_TexteditState *state)
+{
+   stb_textedit_clamp(str, state);
+   if (STB_TEXT_HAS_SELECTION(state)) {
+      if (state->select_start < state->select_end) {
+         stb_textedit_delete(str, state, state->select_start, state->select_end - state->select_start);
+         state->select_end = state->cursor = state->select_start;
+      } else {
+         stb_textedit_delete(str, state, state->select_end, state->select_start - state->select_end);
+         state->select_start = state->cursor = state->select_end;
+      }
+      state->has_preferred_x = 0;
+   }
+}
+
+// canoncialize the selection so start <= end
+static void stb_textedit_sortselection(STB_TexteditState *state)
+{
+   if (state->select_end < state->select_start) {
+      int temp = state->select_end;
+      state->select_end = state->select_start;
+      state->select_start = temp;
+   }
+}
+
+// move cursor to first character of selection
+static void stb_textedit_move_to_first(STB_TexteditState *state)
+{
+   if (STB_TEXT_HAS_SELECTION(state)) {
+      stb_textedit_sortselection(state);
+      state->cursor = state->select_start;
+      state->select_end = state->select_start;
+      state->has_preferred_x = 0;
+   }
+}
+
+// move cursor to last character of selection
+static void stb_textedit_move_to_last(STB_TEXTEDIT_STRING *str, STB_TexteditState *state)
+{
+   if (STB_TEXT_HAS_SELECTION(state)) {
+      stb_textedit_sortselection(state);
+      stb_textedit_clamp(str, state);
+      state->cursor = state->select_end;
+      state->select_start = state->select_end;
+      state->has_preferred_x = 0;
+   }
+}
+
+#ifdef STB_TEXTEDIT_IS_SPACE
+static int is_word_boundary( STB_TEXTEDIT_STRING *str, int idx )
+{
+   return idx > 0 ? (STB_TEXTEDIT_IS_SPACE( STB_TEXTEDIT_GETCHAR(str,idx-1) ) && !STB_TEXTEDIT_IS_SPACE( STB_TEXTEDIT_GETCHAR(str, idx) ) ) : 1;
+}
+
+#ifndef STB_TEXTEDIT_MOVEWORDLEFT
+static int stb_textedit_move_to_word_previous( STB_TEXTEDIT_STRING *str, int c )
+{
+   --c; // always move at least one character
+   while( c >= 0 && !is_word_boundary( str, c ) )
+      --c;
+
+   if( c < 0 )
+      c = 0;
+
+   return c;
+}
+#define STB_TEXTEDIT_MOVEWORDLEFT stb_textedit_move_to_word_previous
+#endif
+
+#ifndef STB_TEXTEDIT_MOVEWORDRIGHT
+static int stb_textedit_move_to_word_next( STB_TEXTEDIT_STRING *str, int c )
+{
+   const int len = STB_TEXTEDIT_STRINGLEN(str);
+   ++c; // always move at least one character
+   while( c < len && !is_word_boundary( str, c ) )
+      ++c;
+
+   if( c > len )
+      c = len;
+
+   return c;
+}
+#define STB_TEXTEDIT_MOVEWORDRIGHT stb_textedit_move_to_word_next
+#endif
+
+#endif
+
+// update selection and cursor to match each other
+static void stb_textedit_prep_selection_at_cursor(STB_TexteditState *state)
+{
+   if (!STB_TEXT_HAS_SELECTION(state))
+      state->select_start = state->select_end = state->cursor;
+   else
+      state->cursor = state->select_end;
+}
+
+// API cut: delete selection
+static int stb_textedit_cut(STB_TEXTEDIT_STRING *str, STB_TexteditState *state)
+{
+   if (STB_TEXT_HAS_SELECTION(state)) {
+      stb_textedit_delete_selection(str,state); // implicitly clamps
+      state->has_preferred_x = 0;
+      return 1;
+   }
+   return 0;
+}
+
+// API paste: replace existing selection with passed-in text
+static int stb_textedit_paste_internal(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, STB_TEXTEDIT_CHARTYPE *text, int len)
+{
+   // if there's a selection, the paste should delete it
+   stb_textedit_clamp(str, state);
+   stb_textedit_delete_selection(str,state);
+   // try to insert the characters
+   if (STB_TEXTEDIT_INSERTCHARS(str, state->cursor, text, len)) {
+      stb_text_makeundo_insert(state, state->cursor, len);
+      state->cursor += len;
+      state->has_preferred_x = 0;
+      return 1;
+   }
+   // remove the undo since we didn't actually insert the characters
+   if (state->undostate.undo_point)
+      --state->undostate.undo_point;
+   return 0;
+}
+
+#ifndef STB_TEXTEDIT_KEYTYPE
+#define STB_TEXTEDIT_KEYTYPE int
+#endif
+
+// API key: process a keyboard input
+static void stb_textedit_key(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, STB_TEXTEDIT_KEYTYPE key)
+{
+retry:
+   switch (key) {
+      default: {
+         int c = STB_TEXTEDIT_KEYTOTEXT(key);
+         if (c > 0) {
+            STB_TEXTEDIT_CHARTYPE ch = (STB_TEXTEDIT_CHARTYPE) c;
+
+            // can't add newline in single-line mode
+            if (c == '\n' && state->single_line)
+               break;
+
+            if (state->insert_mode && !STB_TEXT_HAS_SELECTION(state) && state->cursor < STB_TEXTEDIT_STRINGLEN(str)) {
+               stb_text_makeundo_replace(str, state, state->cursor, 1, 1);
+               STB_TEXTEDIT_DELETECHARS(str, state->cursor, 1);
+               if (STB_TEXTEDIT_INSERTCHARS(str, state->cursor, &ch, 1)) {
+                  ++state->cursor;
+                  state->has_preferred_x = 0;
+               }
+            } else {
+               stb_textedit_delete_selection(str,state); // implicitly clamps
+               if (STB_TEXTEDIT_INSERTCHARS(str, state->cursor, &ch, 1)) {
+                  stb_text_makeundo_insert(state, state->cursor, 1);
+                  ++state->cursor;
+                  state->has_preferred_x = 0;
+               }
+            }
+         }
+         break;
+      }
+
+#ifdef STB_TEXTEDIT_K_INSERT
+      case STB_TEXTEDIT_K_INSERT:
+         state->insert_mode = !state->insert_mode;
+         break;
+#endif
+         
+      case STB_TEXTEDIT_K_UNDO:
+         stb_text_undo(str, state);
+         state->has_preferred_x = 0;
+         break;
+
+      case STB_TEXTEDIT_K_REDO:
+         stb_text_redo(str, state);
+         state->has_preferred_x = 0;
+         break;
+
+      case STB_TEXTEDIT_K_LEFT:
+         // if currently there's a selection, move cursor to start of selection
+         if (STB_TEXT_HAS_SELECTION(state))
+            stb_textedit_move_to_first(state);
+         else 
+            if (state->cursor > 0)
+               --state->cursor;
+         state->has_preferred_x = 0;
+         break;
+
+      case STB_TEXTEDIT_K_RIGHT:
+         // if currently there's a selection, move cursor to end of selection
+         if (STB_TEXT_HAS_SELECTION(state))
+            stb_textedit_move_to_last(str, state);
+         else
+            ++state->cursor;
+         stb_textedit_clamp(str, state);
+         state->has_preferred_x = 0;
+         break;
+
+      case STB_TEXTEDIT_K_LEFT | STB_TEXTEDIT_K_SHIFT:
+         stb_textedit_clamp(str, state);
+         stb_textedit_prep_selection_at_cursor(state);
+         // move selection left
+         if (state->select_end > 0)
+            --state->select_end;
+         state->cursor = state->select_end;
+         state->has_preferred_x = 0;
+         break;
+
+#ifdef STB_TEXTEDIT_MOVEWORDLEFT
+      case STB_TEXTEDIT_K_WORDLEFT:
+         if (STB_TEXT_HAS_SELECTION(state))
+            stb_textedit_move_to_first(state);
+         else {
+            state->cursor = STB_TEXTEDIT_MOVEWORDLEFT(str, state->cursor);
+            stb_textedit_clamp( str, state );
+         }
+         break;
+
+      case STB_TEXTEDIT_K_WORDLEFT | STB_TEXTEDIT_K_SHIFT:
+         if( !STB_TEXT_HAS_SELECTION( state ) )
+            stb_textedit_prep_selection_at_cursor(state);
+
+         state->cursor = STB_TEXTEDIT_MOVEWORDLEFT(str, state->cursor);
+         state->select_end = state->cursor;
+
+         stb_textedit_clamp( str, state );
+         break;
+#endif
+
+#ifdef STB_TEXTEDIT_MOVEWORDRIGHT
+      case STB_TEXTEDIT_K_WORDRIGHT:
+         if (STB_TEXT_HAS_SELECTION(state)) 
+            stb_textedit_move_to_last(str, state);
+         else {
+            state->cursor = STB_TEXTEDIT_MOVEWORDRIGHT(str, state->cursor);
+            stb_textedit_clamp( str, state );
+         }
+         break;
+
+      case STB_TEXTEDIT_K_WORDRIGHT | STB_TEXTEDIT_K_SHIFT:
+         if( !STB_TEXT_HAS_SELECTION( state ) )
+            stb_textedit_prep_selection_at_cursor(state);
+
+         state->cursor = STB_TEXTEDIT_MOVEWORDRIGHT(str, state->cursor);
+         state->select_end = state->cursor;
+
+         stb_textedit_clamp( str, state );
+         break;
+#endif
+
+      case STB_TEXTEDIT_K_RIGHT | STB_TEXTEDIT_K_SHIFT:
+         stb_textedit_prep_selection_at_cursor(state);
+         // move selection right
+         ++state->select_end;
+         stb_textedit_clamp(str, state);
+         state->cursor = state->select_end;
+         state->has_preferred_x = 0;
+         break;
+
+      case STB_TEXTEDIT_K_DOWN:
+      case STB_TEXTEDIT_K_DOWN | STB_TEXTEDIT_K_SHIFT: {
+         StbFindState find;
+         StbTexteditRow row;
+         int i, sel = (key & STB_TEXTEDIT_K_SHIFT) != 0;
+
+         if (state->single_line) {
+            // on windows, up&down in single-line behave like left&right
+            key = STB_TEXTEDIT_K_RIGHT | (key & STB_TEXTEDIT_K_SHIFT);
+            goto retry;
+         }
+
+         if (sel)
+            stb_textedit_prep_selection_at_cursor(state);
+         else if (STB_TEXT_HAS_SELECTION(state))
+            stb_textedit_move_to_last(str,state);
+
+         // compute current position of cursor point
+         stb_textedit_clamp(str, state);
+         stb_textedit_find_charpos(&find, str, state->cursor, state->single_line);
+
+         // now find character position down a row
+         if (find.length) {
+            float goal_x = state->has_preferred_x ? state->preferred_x : find.x;
+            float x;
+            int start = find.first_char + find.length;
+            state->cursor = start;
+            STB_TEXTEDIT_LAYOUTROW(&row, str, state->cursor);
+            x = row.x0;
+            for (i=0; i < row.num_chars; ++i) {
+               float dx = STB_TEXTEDIT_GETWIDTH(str, start, i);
+               #ifdef STB_TEXTEDIT_GETWIDTH_NEWLINE
+               if (dx == STB_TEXTEDIT_GETWIDTH_NEWLINE)
+                  break;
+               #endif
+               x += dx;
+               if (x > goal_x)
+                  break;
+               ++state->cursor;
+            }
+            stb_textedit_clamp(str, state);
+
+            state->has_preferred_x = 1;
+            state->preferred_x = goal_x;
+
+            if (sel)
+               state->select_end = state->cursor;
+         }
+         break;
+      }
+         
+      case STB_TEXTEDIT_K_UP:
+      case STB_TEXTEDIT_K_UP | STB_TEXTEDIT_K_SHIFT: {
+         StbFindState find;
+         StbTexteditRow row;
+         int i, sel = (key & STB_TEXTEDIT_K_SHIFT) != 0;
+
+         if (state->single_line) {
+            // on windows, up&down become left&right
+            key = STB_TEXTEDIT_K_LEFT | (key & STB_TEXTEDIT_K_SHIFT);
+            goto retry;
+         }
+
+         if (sel)
+            stb_textedit_prep_selection_at_cursor(state);
+         else if (STB_TEXT_HAS_SELECTION(state))
+            stb_textedit_move_to_first(state);
+
+         // compute current position of cursor point
+         stb_textedit_clamp(str, state);
+         stb_textedit_find_charpos(&find, str, state->cursor, state->single_line);
+
+         // can only go up if there's a previous row
+         if (find.prev_first != find.first_char) {
+            // now find character position up a row
+            float goal_x = state->has_preferred_x ? state->preferred_x : find.x;
+            float x;
+            state->cursor = find.prev_first;
+            STB_TEXTEDIT_LAYOUTROW(&row, str, state->cursor);
+            x = row.x0;
+            for (i=0; i < row.num_chars; ++i) {
+               float dx = STB_TEXTEDIT_GETWIDTH(str, find.prev_first, i);
+               #ifdef STB_TEXTEDIT_GETWIDTH_NEWLINE
+               if (dx == STB_TEXTEDIT_GETWIDTH_NEWLINE)
+                  break;
+               #endif
+               x += dx;
+               if (x > goal_x)
+                  break;
+               ++state->cursor;
+            }
+            stb_textedit_clamp(str, state);
+
+            state->has_preferred_x = 1;
+            state->preferred_x = goal_x;
+
+            if (sel)
+               state->select_end = state->cursor;
+         }
+         break;
+      }
+
+      case STB_TEXTEDIT_K_DELETE:
+      case STB_TEXTEDIT_K_DELETE | STB_TEXTEDIT_K_SHIFT:
+         if (STB_TEXT_HAS_SELECTION(state))
+            stb_textedit_delete_selection(str, state);
+         else {
+            int n = STB_TEXTEDIT_STRINGLEN(str);
+            if (state->cursor < n)
+               stb_textedit_delete(str, state, state->cursor, 1);
+         }
+         state->has_preferred_x = 0;
+         break;
+
+      case STB_TEXTEDIT_K_BACKSPACE:
+      case STB_TEXTEDIT_K_BACKSPACE | STB_TEXTEDIT_K_SHIFT:
+         if (STB_TEXT_HAS_SELECTION(state))
+            stb_textedit_delete_selection(str, state);
+         else {
+            stb_textedit_clamp(str, state);
+            if (state->cursor > 0) {
+               stb_textedit_delete(str, state, state->cursor-1, 1);
+               --state->cursor;
+            }
+         }
+         state->has_preferred_x = 0;
+         break;
+         
+#ifdef STB_TEXTEDIT_K_TEXTSTART2
+      case STB_TEXTEDIT_K_TEXTSTART2:
+#endif
+      case STB_TEXTEDIT_K_TEXTSTART:
+         state->cursor = state->select_start = state->select_end = 0;
+         state->has_preferred_x = 0;
+         break;
+
+#ifdef STB_TEXTEDIT_K_TEXTEND2
+      case STB_TEXTEDIT_K_TEXTEND2:
+#endif
+      case STB_TEXTEDIT_K_TEXTEND:
+         state->cursor = STB_TEXTEDIT_STRINGLEN(str);
+         state->select_start = state->select_end = 0;
+         state->has_preferred_x = 0;
+         break;
+        
+#ifdef STB_TEXTEDIT_K_TEXTSTART2
+      case STB_TEXTEDIT_K_TEXTSTART2 | STB_TEXTEDIT_K_SHIFT:
+#endif
+      case STB_TEXTEDIT_K_TEXTSTART | STB_TEXTEDIT_K_SHIFT:
+         stb_textedit_prep_selection_at_cursor(state);
+         state->cursor = state->select_end = 0;
+         state->has_preferred_x = 0;
+         break;
+
+#ifdef STB_TEXTEDIT_K_TEXTEND2
+      case STB_TEXTEDIT_K_TEXTEND2 | STB_TEXTEDIT_K_SHIFT:
+#endif
+      case STB_TEXTEDIT_K_TEXTEND | STB_TEXTEDIT_K_SHIFT:
+         stb_textedit_prep_selection_at_cursor(state);
+         state->cursor = state->select_end = STB_TEXTEDIT_STRINGLEN(str);
+         state->has_preferred_x = 0;
+         break;
+
+
+#ifdef STB_TEXTEDIT_K_LINESTART2
+      case STB_TEXTEDIT_K_LINESTART2:
+#endif
+      case STB_TEXTEDIT_K_LINESTART:
+         stb_textedit_clamp(str, state);
+         stb_textedit_move_to_first(state);
+         if (state->single_line)
+            state->cursor = 0;
+         else while (state->cursor > 0 && STB_TEXTEDIT_GETCHAR(str, state->cursor-1) != STB_TEXTEDIT_NEWLINE)
+            --state->cursor;
+         state->has_preferred_x = 0;
+         break;
+
+#ifdef STB_TEXTEDIT_K_LINEEND2
+      case STB_TEXTEDIT_K_LINEEND2:
+#endif
+      case STB_TEXTEDIT_K_LINEEND: {
+         int n = STB_TEXTEDIT_STRINGLEN(str);
+         stb_textedit_clamp(str, state);
+         stb_textedit_move_to_first(state);
+         if (state->single_line)
+             state->cursor = n;
+         else while (state->cursor < n && STB_TEXTEDIT_GETCHAR(str, state->cursor) != STB_TEXTEDIT_NEWLINE)
+             ++state->cursor;
+         state->has_preferred_x = 0;
+         break;
+      }
+
+#ifdef STB_TEXTEDIT_K_LINESTART2
+      case STB_TEXTEDIT_K_LINESTART2 | STB_TEXTEDIT_K_SHIFT:
+#endif
+      case STB_TEXTEDIT_K_LINESTART | STB_TEXTEDIT_K_SHIFT:
+         stb_textedit_clamp(str, state);
+         stb_textedit_prep_selection_at_cursor(state);
+         if (state->single_line)
+            state->cursor = 0;
+         else while (state->cursor > 0 && STB_TEXTEDIT_GETCHAR(str, state->cursor-1) != STB_TEXTEDIT_NEWLINE)
+            --state->cursor;
+         state->select_end = state->cursor;
+         state->has_preferred_x = 0;
+         break;
+
+#ifdef STB_TEXTEDIT_K_LINEEND2
+      case STB_TEXTEDIT_K_LINEEND2 | STB_TEXTEDIT_K_SHIFT:
+#endif
+      case STB_TEXTEDIT_K_LINEEND | STB_TEXTEDIT_K_SHIFT: {
+         int n = STB_TEXTEDIT_STRINGLEN(str);
+         stb_textedit_clamp(str, state);
+         stb_textedit_prep_selection_at_cursor(state);
+         if (state->single_line)
+             state->cursor = n;
+         else while (state->cursor < n && STB_TEXTEDIT_GETCHAR(str, state->cursor) != STB_TEXTEDIT_NEWLINE)
+            ++state->cursor;
+         state->select_end = state->cursor;
+         state->has_preferred_x = 0;
+         break;
+      }
+
+// @TODO:
+//    STB_TEXTEDIT_K_PGUP      - move cursor up a page
+//    STB_TEXTEDIT_K_PGDOWN    - move cursor down a page
+   }
+}
+
+/////////////////////////////////////////////////////////////////////////////
+//
+//      Undo processing
+//
+// @OPTIMIZE: the undo/redo buffer should be circular
+
+static void stb_textedit_flush_redo(StbUndoState *state)
+{
+   state->redo_point = STB_TEXTEDIT_UNDOSTATECOUNT;
+   state->redo_char_point = STB_TEXTEDIT_UNDOCHARCOUNT;
+}
+
+// discard the oldest entry in the undo list
+static void stb_textedit_discard_undo(StbUndoState *state)
+{
+   if (state->undo_point > 0) {
+      // if the 0th undo state has characters, clean those up
+      if (state->undo_rec[0].char_storage >= 0) {
+         int n = state->undo_rec[0].insert_length, i;
+         // delete n characters from all other records
+         state->undo_char_point -= n;
+         STB_TEXTEDIT_memmove(state->undo_char, state->undo_char + n, (size_t) (state->undo_char_point*sizeof(STB_TEXTEDIT_CHARTYPE)));
+         for (i=0; i < state->undo_point; ++i)
+            if (state->undo_rec[i].char_storage >= 0)
+               state->undo_rec[i].char_storage -= n; // @OPTIMIZE: get rid of char_storage and infer it
+      }
+      --state->undo_point;
+      STB_TEXTEDIT_memmove(state->undo_rec, state->undo_rec+1, (size_t) (state->undo_point*sizeof(state->undo_rec[0])));
+   }
+}
+
+// discard the oldest entry in the redo list--it's bad if this
+// ever happens, but because undo & redo have to store the actual
+// characters in different cases, the redo character buffer can
+// fill up even though the undo buffer didn't
+static void stb_textedit_discard_redo(StbUndoState *state)
+{
+   int k = STB_TEXTEDIT_UNDOSTATECOUNT-1;
+
+   if (state->redo_point <= k) {
+      // if the k'th undo state has characters, clean those up
+      if (state->undo_rec[k].char_storage >= 0) {
+         int n = state->undo_rec[k].insert_length, i;
+         // move the remaining redo character data to the end of the buffer
+         state->redo_char_point += n;
+         STB_TEXTEDIT_memmove(state->undo_char + state->redo_char_point, state->undo_char + state->redo_char_point-n, (size_t) ((STB_TEXTEDIT_UNDOCHARCOUNT - state->redo_char_point)*sizeof(STB_TEXTEDIT_CHARTYPE)));
+         // adjust the position of all the other records to account for above memmove
+         for (i=state->redo_point; i < k; ++i)
+            if (state->undo_rec[i].char_storage >= 0)
+               state->undo_rec[i].char_storage += n;
+      }
+      // now move all the redo records towards the end of the buffer; the first one is at 'redo_point'
+      // {DEAR IMGUI]
+      size_t move_size = (size_t)((STB_TEXTEDIT_UNDOSTATECOUNT - state->redo_point - 1) * sizeof(state->undo_rec[0]));
+      const char* buf_begin = (char*)state->undo_rec; (void)buf_begin;
+      const char* buf_end   = (char*)state->undo_rec + sizeof(state->undo_rec); (void)buf_end;
+      IM_ASSERT(((char*)(state->undo_rec + state->redo_point)) >= buf_begin);
+      IM_ASSERT(((char*)(state->undo_rec + state->redo_point + 1) + move_size) <= buf_end);
+      STB_TEXTEDIT_memmove(state->undo_rec + state->redo_point+1, state->undo_rec + state->redo_point, move_size);
+
+      // now move redo_point to point to the new one
+      ++state->redo_point;
+   }
+}
+
+static StbUndoRecord *stb_text_create_undo_record(StbUndoState *state, int numchars)
+{
+   // any time we create a new undo record, we discard redo
+   stb_textedit_flush_redo(state);
+
+   // if we have no free records, we have to make room, by sliding the
+   // existing records down
+   if (state->undo_point == STB_TEXTEDIT_UNDOSTATECOUNT)
+      stb_textedit_discard_undo(state);
+
+   // if the characters to store won't possibly fit in the buffer, we can't undo
+   if (numchars > STB_TEXTEDIT_UNDOCHARCOUNT) {
+      state->undo_point = 0;
+      state->undo_char_point = 0;
+      return NULL;
+   }
+
+   // if we don't have enough free characters in the buffer, we have to make room
+   while (state->undo_char_point + numchars > STB_TEXTEDIT_UNDOCHARCOUNT)
+      stb_textedit_discard_undo(state);
+
+   return &state->undo_rec[state->undo_point++];
+}
+
+static STB_TEXTEDIT_CHARTYPE *stb_text_createundo(StbUndoState *state, int pos, int insert_len, int delete_len)
+{
+   StbUndoRecord *r = stb_text_create_undo_record(state, insert_len);
+   if (r == NULL)
+      return NULL;
+
+   r->where = pos;
+   r->insert_length = (STB_TEXTEDIT_POSITIONTYPE) insert_len;
+   r->delete_length = (STB_TEXTEDIT_POSITIONTYPE) delete_len;
+
+   if (insert_len == 0) {
+      r->char_storage = -1;
+      return NULL;
+   } else {
+      r->char_storage = state->undo_char_point;
+      state->undo_char_point += insert_len;
+      return &state->undo_char[r->char_storage];
+   }
+}
+
+static void stb_text_undo(STB_TEXTEDIT_STRING *str, STB_TexteditState *state)
+{
+   StbUndoState *s = &state->undostate;
+   StbUndoRecord u, *r;
+   if (s->undo_point == 0)
+      return;
+
+   // we need to do two things: apply the undo record, and create a redo record
+   u = s->undo_rec[s->undo_point-1];
+   r = &s->undo_rec[s->redo_point-1];
+   r->char_storage = -1;
+
+   r->insert_length = u.delete_length;
+   r->delete_length = u.insert_length;
+   r->where = u.where;
+
+   if (u.delete_length) {
+      // if the undo record says to delete characters, then the redo record will
+      // need to re-insert the characters that get deleted, so we need to store
+      // them.
+
+      // there are three cases:
+      //    there's enough room to store the characters
+      //    characters stored for *redoing* don't leave room for redo
+      //    characters stored for *undoing* don't leave room for redo
+      // if the last is true, we have to bail
+
+      if (s->undo_char_point + u.delete_length >= STB_TEXTEDIT_UNDOCHARCOUNT) {
+         // the undo records take up too much character space; there's no space to store the redo characters
+         r->insert_length = 0;
+      } else {
+         int i;
+
+         // there's definitely room to store the characters eventually
+         while (s->undo_char_point + u.delete_length > s->redo_char_point) {
+            // should never happen:
+            if (s->redo_point == STB_TEXTEDIT_UNDOSTATECOUNT)
+               return;
+            // there's currently not enough room, so discard a redo record
+            stb_textedit_discard_redo(s);
+         }
+         r = &s->undo_rec[s->redo_point-1];
+
+         r->char_storage = s->redo_char_point - u.delete_length;
+         s->redo_char_point = s->redo_char_point - u.delete_length;
+
+         // now save the characters
+         for (i=0; i < u.delete_length; ++i)
+            s->undo_char[r->char_storage + i] = STB_TEXTEDIT_GETCHAR(str, u.where + i);
+      }
+
+      // now we can carry out the deletion
+      STB_TEXTEDIT_DELETECHARS(str, u.where, u.delete_length);
+   }
+
+   // check type of recorded action:
+   if (u.insert_length) {
+      // easy case: was a deletion, so we need to insert n characters
+      STB_TEXTEDIT_INSERTCHARS(str, u.where, &s->undo_char[u.char_storage], u.insert_length);
+      s->undo_char_point -= u.insert_length;
+   }
+
+   state->cursor = u.where + u.insert_length;
+
+   s->undo_point--;
+   s->redo_point--;
+}
+
+static void stb_text_redo(STB_TEXTEDIT_STRING *str, STB_TexteditState *state)
+{
+   StbUndoState *s = &state->undostate;
+   StbUndoRecord *u, r;
+   if (s->redo_point == STB_TEXTEDIT_UNDOSTATECOUNT)
+      return;
+
+   // we need to do two things: apply the redo record, and create an undo record
+   u = &s->undo_rec[s->undo_point];
+   r = s->undo_rec[s->redo_point];
+
+   // we KNOW there must be room for the undo record, because the redo record
+   // was derived from an undo record
+
+   u->delete_length = r.insert_length;
+   u->insert_length = r.delete_length;
+   u->where = r.where;
+   u->char_storage = -1;
+
+   if (r.delete_length) {
+      // the redo record requires us to delete characters, so the undo record
+      // needs to store the characters
+
+      if (s->undo_char_point + u->insert_length > s->redo_char_point) {
+         u->insert_length = 0;
+         u->delete_length = 0;
+      } else {
+         int i;
+         u->char_storage = s->undo_char_point;
+         s->undo_char_point = s->undo_char_point + u->insert_length;
+
+         // now save the characters
+         for (i=0; i < u->insert_length; ++i)
+            s->undo_char[u->char_storage + i] = STB_TEXTEDIT_GETCHAR(str, u->where + i);
+      }
+
+      STB_TEXTEDIT_DELETECHARS(str, r.where, r.delete_length);
+   }
+
+   if (r.insert_length) {
+      // easy case: need to insert n characters
+      STB_TEXTEDIT_INSERTCHARS(str, r.where, &s->undo_char[r.char_storage], r.insert_length);
+      s->redo_char_point += r.insert_length;
+   }
+
+   state->cursor = r.where + r.insert_length;
+
+   s->undo_point++;
+   s->redo_point++;
+}
+
+static void stb_text_makeundo_insert(STB_TexteditState *state, int where, int length)
+{
+   stb_text_createundo(&state->undostate, where, 0, length);
+}
+
+static void stb_text_makeundo_delete(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, int where, int length)
+{
+   int i;
+   STB_TEXTEDIT_CHARTYPE *p = stb_text_createundo(&state->undostate, where, length, 0);
+   if (p) {
+      for (i=0; i < length; ++i)
+         p[i] = STB_TEXTEDIT_GETCHAR(str, where+i);
+   }
+}
+
+static void stb_text_makeundo_replace(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, int where, int old_length, int new_length)
+{
+   int i;
+   STB_TEXTEDIT_CHARTYPE *p = stb_text_createundo(&state->undostate, where, old_length, new_length);
+   if (p) {
+      for (i=0; i < old_length; ++i)
+         p[i] = STB_TEXTEDIT_GETCHAR(str, where+i);
+   }
+}
+
+// reset the state to default
+static void stb_textedit_clear_state(STB_TexteditState *state, int is_single_line)
+{
+   state->undostate.undo_point = 0;
+   state->undostate.undo_char_point = 0;
+   state->undostate.redo_point = STB_TEXTEDIT_UNDOSTATECOUNT;
+   state->undostate.redo_char_point = STB_TEXTEDIT_UNDOCHARCOUNT;
+   state->select_end = state->select_start = 0;
+   state->cursor = 0;
+   state->has_preferred_x = 0;
+   state->preferred_x = 0;
+   state->cursor_at_end_of_line = 0;
+   state->initialized = 1;
+   state->single_line = (unsigned char) is_single_line;
+   state->insert_mode = 0;
+}
+
+// API initialize
+static void stb_textedit_initialize_state(STB_TexteditState *state, int is_single_line)
+{
+   stb_textedit_clear_state(state, is_single_line);
+}
+
+#if defined(__GNUC__) || defined(__clang__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wcast-qual"
+#endif
+
+static int stb_textedit_paste(STB_TEXTEDIT_STRING *str, STB_TexteditState *state, STB_TEXTEDIT_CHARTYPE const *ctext, int len)
+{
+   return stb_textedit_paste_internal(str, state, (STB_TEXTEDIT_CHARTYPE *) ctext, len);
+}
+
+#if defined(__GNUC__) || defined(__clang__)
+#pragma GCC diagnostic pop
+#endif
+
+#endif//STB_TEXTEDIT_IMPLEMENTATION
+
+/*
+------------------------------------------------------------------------------
+This software is available under 2 licenses -- choose whichever you prefer.
+------------------------------------------------------------------------------
+ALTERNATIVE A - MIT License
+Copyright (c) 2017 Sean Barrett
+Permission is hereby granted, free of charge, to any person obtaining a copy of 
+this software and associated documentation files (the "Software"), to deal in 
+the Software without restriction, including without limitation the rights to 
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies 
+of the Software, and to permit persons to whom the Software is furnished to do 
+so, subject to the following conditions:
+The above copyright notice and this permission notice shall be included in all 
+copies or substantial portions of the Software.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 
+SOFTWARE.
+------------------------------------------------------------------------------
+ALTERNATIVE B - Public Domain (www.unlicense.org)
+This is free and unencumbered software released into the public domain.
+Anyone is free to copy, modify, publish, use, compile, sell, or distribute this 
+software, either in source code form or as a compiled binary, for any purpose, 
+commercial or non-commercial, and by any means.
+In jurisdictions that recognize copyright laws, the author or authors of this 
+software dedicate any and all copyright interest in the software to the public 
+domain. We make this dedication for the benefit of the public at large and to 
+the detriment of our heirs and successors. We intend this dedication to be an 
+overt act of relinquishment in perpetuity of all present and future rights to 
+this software under copyright law.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
+AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 
+ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+------------------------------------------------------------------------------
+*/

include/imgui/imstb_truetype.h

+// [DEAR IMGUI]
+// This is a slightly modified version of stb_truetype.h 1.20.
+// Mostly fixing for compiler and static analyzer warnings.
+// Grep for [DEAR IMGUI] to find the changes.
+
+// stb_truetype.h - v1.20 - public domain
+// authored from 2009-2016 by Sean Barrett / RAD Game Tools
+//
+//   This library processes TrueType files:
+//        parse files
+//        extract glyph metrics
+//        extract glyph shapes
+//        render glyphs to one-channel bitmaps with antialiasing (box filter)
+//        render glyphs to one-channel SDF bitmaps (signed-distance field/function)
+//
+//   Todo:
+//        non-MS cmaps
+//        crashproof on bad data
+//        hinting? (no longer patented)
+//        cleartype-style AA?
+//        optimize: use simple memory allocator for intermediates
+//        optimize: build edge-list directly from curves
+//        optimize: rasterize directly from curves?
+//
+// ADDITIONAL CONTRIBUTORS
+//
+//   Mikko Mononen: compound shape support, more cmap formats
+//   Tor Andersson: kerning, subpixel rendering
+//   Dougall Johnson: OpenType / Type 2 font handling
+//   Daniel Ribeiro Maciel: basic GPOS-based kerning
+//
+//   Misc other:
+//       Ryan Gordon
+//       Simon Glass
+//       github:IntellectualKitty
+//       Imanol Celaya
+//       Daniel Ribeiro Maciel
+//
+//   Bug/warning reports/fixes:
+//       "Zer" on mollyrocket       Fabian "ryg" Giesen
+//       Cass Everitt               Martins Mozeiko
+//       stoiko (Haemimont Games)   Cap Petschulat
+//       Brian Hook                 Omar Cornut
+//       Walter van Niftrik         github:aloucks
+//       David Gow                  Peter LaValle
+//       David Given                Sergey Popov
+//       Ivan-Assen Ivanov          Giumo X. Clanjor
+//       Anthony Pesch              Higor Euripedes
+//       Johan Duparc               Thomas Fields
+//       Hou Qiming                 Derek Vinyard
+//       Rob Loach                  Cort Stratton
+//       Kenney Phillis Jr.         github:oyvindjam
+//       Brian Costabile            github:vassvik
+//       
+// VERSION HISTORY
+//
+//   1.20 (2019-02-07) PackFontRange skips missing codepoints; GetScaleFontVMetrics()
+//   1.19 (2018-02-11) GPOS kerning, STBTT_fmod
+//   1.18 (2018-01-29) add missing function
+//   1.17 (2017-07-23) make more arguments const; doc fix
+//   1.16 (2017-07-12) SDF support
+//   1.15 (2017-03-03) make more arguments const
+//   1.14 (2017-01-16) num-fonts-in-TTC function
+//   1.13 (2017-01-02) support OpenType fonts, certain Apple fonts
+//   1.12 (2016-10-25) suppress warnings about casting away const with -Wcast-qual
+//   1.11 (2016-04-02) fix unused-variable warning
+//   1.10 (2016-04-02) user-defined fabs(); rare memory leak; remove duplicate typedef
+//   1.09 (2016-01-16) warning fix; avoid crash on outofmem; use allocation userdata properly
+//   1.08 (2015-09-13) document stbtt_Rasterize(); fixes for vertical & horizontal edges
+//   1.07 (2015-08-01) allow PackFontRanges to accept arrays of sparse codepoints;
+//                     variant PackFontRanges to pack and render in separate phases;
+//                     fix stbtt_GetFontOFfsetForIndex (never worked for non-0 input?);
+//                     fixed an assert() bug in the new rasterizer
+//                     replace assert() with STBTT_assert() in new rasterizer
+//
+//   Full history can be found at the end of this file.
+//
+// LICENSE
+//
+//   See end of file for license information.
+//
+// USAGE
+//
+//   Include this file in whatever places need to refer to it. In ONE C/C++
+//   file, write:
+//      #define STB_TRUETYPE_IMPLEMENTATION
+//   before the #include of this file. This expands out the actual
+//   implementation into that C/C++ file.
+//
+//   To make the implementation private to the file that generates the implementation,
+//      #define STBTT_STATIC
+//
+//   Simple 3D API (don't ship this, but it's fine for tools and quick start)
+//           stbtt_BakeFontBitmap()               -- bake a font to a bitmap for use as texture
+//           stbtt_GetBakedQuad()                 -- compute quad to draw for a given char
+//
+//   Improved 3D API (more shippable):
+//           #include "stb_rect_pack.h"           -- optional, but you really want it
+//           stbtt_PackBegin()
+//           stbtt_PackSetOversampling()          -- for improved quality on small fonts
+//           stbtt_PackFontRanges()               -- pack and renders
+//           stbtt_PackEnd()
+//           stbtt_GetPackedQuad()
+//
+//   "Load" a font file from a memory buffer (you have to keep the buffer loaded)
+//           stbtt_InitFont()
+//           stbtt_GetFontOffsetForIndex()        -- indexing for TTC font collections
+//           stbtt_GetNumberOfFonts()             -- number of fonts for TTC font collections
+//
+//   Render a unicode codepoint to a bitmap
+//           stbtt_GetCodepointBitmap()           -- allocates and returns a bitmap
+//           stbtt_MakeCodepointBitmap()          -- renders into bitmap you provide
+//           stbtt_GetCodepointBitmapBox()        -- how big the bitmap must be
+//
+//   Character advance/positioning
+//           stbtt_GetCodepointHMetrics()
+//           stbtt_GetFontVMetrics()
+//           stbtt_GetFontVMetricsOS2()
+//           stbtt_GetCodepointKernAdvance()
+//
+//   Starting with version 1.06, the rasterizer was replaced with a new,
+//   faster and generally-more-precise rasterizer. The new rasterizer more
+//   accurately measures pixel coverage for anti-aliasing, except in the case
+//   where multiple shapes overlap, in which case it overestimates the AA pixel
+//   coverage. Thus, anti-aliasing of intersecting shapes may look wrong. If
+//   this turns out to be a problem, you can re-enable the old rasterizer with
+//        #define STBTT_RASTERIZER_VERSION 1
+//   which will incur about a 15% speed hit.
+//
+// ADDITIONAL DOCUMENTATION
+//
+//   Immediately after this block comment are a series of sample programs.
+//
+//   After the sample programs is the "header file" section. This section
+//   includes documentation for each API function.
+//
+//   Some important concepts to understand to use this library:
+//
+//      Codepoint
+//         Characters are defined by unicode codepoints, e.g. 65 is
+//         uppercase A, 231 is lowercase c with a cedilla, 0x7e30 is
+//         the hiragana for "ma".
+//
+//      Glyph
+//         A visual character shape (every codepoint is rendered as
+//         some glyph)
+//
+//      Glyph index
+//         A font-specific integer ID representing a glyph
+//
+//      Baseline
+//         Glyph shapes are defined relative to a baseline, which is the
+//         bottom of uppercase characters. Characters extend both above
+//         and below the baseline.
+//
+//      Current Point
+//         As you draw text to the screen, you keep track of a "current point"
+//         which is the origin of each character. The current point's vertical
+//         position is the baseline. Even "baked fonts" use this model.
+//
+//      Vertical Font Metrics
+//         The vertical qualities of the font, used to vertically position
+//         and space the characters. See docs for stbtt_GetFontVMetrics.
+//
+//      Font Size in Pixels or Points
+//         The preferred interface for specifying font sizes in stb_truetype
+//         is to specify how tall the font's vertical extent should be in pixels.
+//         If that sounds good enough, skip the next paragraph.
+//
+//         Most font APIs instead use "points", which are a common typographic
+//         measurement for describing font size, defined as 72 points per inch.
+//         stb_truetype provides a point API for compatibility. However, true
+//         "per inch" conventions don't make much sense on computer displays
+//         since different monitors have different number of pixels per
+//         inch. For example, Windows traditionally uses a convention that
+//         there are 96 pixels per inch, thus making 'inch' measurements have
+//         nothing to do with inches, and thus effectively defining a point to
+//         be 1.333 pixels. Additionally, the TrueType font data provides
+//         an explicit scale factor to scale a given font's glyphs to points,
+//         but the author has observed that this scale factor is often wrong
+//         for non-commercial fonts, thus making fonts scaled in points
+//         according to the TrueType spec incoherently sized in practice.
+//
+// DETAILED USAGE:
+//
+//  Scale:
+//    Select how high you want the font to be, in points or pixels.
+//    Call ScaleForPixelHeight or ScaleForMappingEmToPixels to compute
+//    a scale factor SF that will be used by all other functions.
+//
+//  Baseline:
+//    You need to select a y-coordinate that is the baseline of where
+//    your text will appear. Call GetFontBoundingBox to get the baseline-relative
+//    bounding box for all characters. SF*-y0 will be the distance in pixels
+//    that the worst-case character could extend above the baseline, so if
+//    you want the top edge of characters to appear at the top of the
+//    screen where y=0, then you would set the baseline to SF*-y0.
+//
+//  Current point:
+//    Set the current point where the first character will appear. The
+//    first character could extend left of the current point; this is font
+//    dependent. You can either choose a current point that is the leftmost
+//    point and hope, or add some padding, or check the bounding box or
+//    left-side-bearing of the first character to be displayed and set
+//    the current point based on that.
+//
+//  Displaying a character:
+//    Compute the bounding box of the character. It will contain signed values
+//    relative to <current_point, baseline>. I.e. if it returns x0,y0,x1,y1,
+//    then the character should be displayed in the rectangle from
+//    <current_point+SF*x0, baseline+SF*y0> to <current_point+SF*x1,baseline+SF*y1).
+//
+//  Advancing for the next character:
+//    Call GlyphHMetrics, and compute 'current_point += SF * advance'.
+// 
+//
+// ADVANCED USAGE
+//
+//   Quality:
+//
+//    - Use the functions with Subpixel at the end to allow your characters
+//      to have subpixel positioning. Since the font is anti-aliased, not
+//      hinted, this is very import for quality. (This is not possible with
+//      baked fonts.)
+//
+//    - Kerning is now supported, and if you're supporting subpixel rendering
+//      then kerning is worth using to give your text a polished look.
+//
+//   Performance:
+//
+//    - Convert Unicode codepoints to glyph indexes and operate on the glyphs;
+//      if you don't do this, stb_truetype is forced to do the conversion on
+//      every call.
+//
+//    - There are a lot of memory allocations. We should modify it to take
+//      a temp buffer and allocate from the temp buffer (without freeing),
+//      should help performance a lot.
+//
+// NOTES
+//
+//   The system uses the raw data found in the .ttf file without changing it
+//   and without building auxiliary data structures. This is a bit inefficient
+//   on little-endian systems (the data is big-endian), but assuming you're
+//   caching the bitmaps or glyph shapes this shouldn't be a big deal.
+//
+//   It appears to be very hard to programmatically determine what font a
+//   given file is in a general way. I provide an API for this, but I don't
+//   recommend it.
+//
+//
+// SOURCE STATISTICS (based on v0.6c, 2050 LOC)
+//
+//   Documentation & header file        520 LOC  \___ 660 LOC documentation
+//   Sample code                        140 LOC  /
+//   Truetype parsing                   620 LOC  ---- 620 LOC TrueType
+//   Software rasterization             240 LOC  \.
+//   Curve tessellation                 120 LOC   \__ 550 LOC Bitmap creation
+//   Bitmap management                  100 LOC   /
+//   Baked bitmap interface              70 LOC  /
+//   Font name matching & access        150 LOC  ---- 150 
+//   C runtime library abstraction       60 LOC  ----  60
+//
+//
+// PERFORMANCE MEASUREMENTS FOR 1.06:
+//
+//                      32-bit     64-bit
+//   Previous release:  8.83 s     7.68 s
+//   Pool allocations:  7.72 s     6.34 s
+//   Inline sort     :  6.54 s     5.65 s
+//   New rasterizer  :  5.63 s     5.00 s
+
+//////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////
+////
+////  SAMPLE PROGRAMS
+////
+//
+//  Incomplete text-in-3d-api example, which draws quads properly aligned to be lossless
+//
+#if 0
+#define STB_TRUETYPE_IMPLEMENTATION  // force following include to generate implementation
+#include "stb_truetype.h"
+
+unsigned char ttf_buffer[1<<20];
+unsigned char temp_bitmap[512*512];
+
+stbtt_bakedchar cdata[96]; // ASCII 32..126 is 95 glyphs
+GLuint ftex;
+
+void my_stbtt_initfont(void)
+{
+   fread(ttf_buffer, 1, 1<<20, fopen("c:/windows/fonts/times.ttf", "rb"));
+   stbtt_BakeFontBitmap(ttf_buffer,0, 32.0, temp_bitmap,512,512, 32,96, cdata); // no guarantee this fits!
+   // can free ttf_buffer at this point
+   glGenTextures(1, &ftex);
+   glBindTexture(GL_TEXTURE_2D, ftex);
+   glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA, 512,512, 0, GL_ALPHA, GL_UNSIGNED_BYTE, temp_bitmap);
+   // can free temp_bitmap at this point
+   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+}
+
+void my_stbtt_print(float x, float y, char *text)
+{
+   // assume orthographic projection with units = screen pixels, origin at top left
+   glEnable(GL_TEXTURE_2D);
+   glBindTexture(GL_TEXTURE_2D, ftex);
+   glBegin(GL_QUADS);
+   while (*text) {
+      if (*text >= 32 && *text < 128) {
+         stbtt_aligned_quad q;
+         stbtt_GetBakedQuad(cdata, 512,512, *text-32, &x,&y,&q,1);//1=opengl & d3d10+,0=d3d9
+         glTexCoord2f(q.s0,q.t1); glVertex2f(q.x0,q.y0);
+         glTexCoord2f(q.s1,q.t1); glVertex2f(q.x1,q.y0);
+         glTexCoord2f(q.s1,q.t0); glVertex2f(q.x1,q.y1);
+         glTexCoord2f(q.s0,q.t0); glVertex2f(q.x0,q.y1);
+      }
+      ++text;
+   }
+   glEnd();
+}
+#endif
+//
+//
+//////////////////////////////////////////////////////////////////////////////
+//
+// Complete program (this compiles): get a single bitmap, print as ASCII art
+//
+#if 0
+#include <stdio.h>
+#define STB_TRUETYPE_IMPLEMENTATION  // force following include to generate implementation
+#include "stb_truetype.h"
+
+char ttf_buffer[1<<25];
+
+int main(int argc, char **argv)
+{
+   stbtt_fontinfo font;
+   unsigned char *bitmap;
+   int w,h,i,j,c = (argc > 1 ? atoi(argv[1]) : 'a'), s = (argc > 2 ? atoi(argv[2]) : 20);
+
+   fread(ttf_buffer, 1, 1<<25, fopen(argc > 3 ? argv[3] : "c:/windows/fonts/arialbd.ttf", "rb"));
+
+   stbtt_InitFont(&font, ttf_buffer, stbtt_GetFontOffsetForIndex(ttf_buffer,0));
+   bitmap = stbtt_GetCodepointBitmap(&font, 0,stbtt_ScaleForPixelHeight(&font, s), c, &w, &h, 0,0);
+
+   for (j=0; j < h; ++j) {
+      for (i=0; i < w; ++i)
+         putchar(" .:ioVM@"[bitmap[j*w+i]>>5]);
+      putchar('\n');
+   }
+   return 0;
+}
+#endif 
+//
+// Output:
+//
+//     .ii.
+//    @@@@@@.
+//   V@Mio@@o
+//   :i.  V@V
+//     :oM@@M
+//   :@@@MM@M
+//   @@o  o@M
+//  :@@.  M@M
+//   @@@o@@@@
+//   :M@@V:@@.
+//  
+//////////////////////////////////////////////////////////////////////////////
+// 
+// Complete program: print "Hello World!" banner, with bugs
+//
+#if 0
+char buffer[24<<20];
+unsigned char screen[20][79];
+
+int main(int arg, char **argv)
+{
+   stbtt_fontinfo font;
+   int i,j,ascent,baseline,ch=0;
+   float scale, xpos=2; // leave a little padding in case the character extends left
+   char *text = "Heljo World!"; // intentionally misspelled to show 'lj' brokenness
+
+   fread(buffer, 1, 1000000, fopen("c:/windows/fonts/arialbd.ttf", "rb"));
+   stbtt_InitFont(&font, buffer, 0);
+
+   scale = stbtt_ScaleForPixelHeight(&font, 15);
+   stbtt_GetFontVMetrics(&font, &ascent,0,0);
+   baseline = (int) (ascent*scale);
+
+   while (text[ch]) {
+      int advance,lsb,x0,y0,x1,y1;
+      float x_shift = xpos - (float) floor(xpos);
+      stbtt_GetCodepointHMetrics(&font, text[ch], &advance, &lsb);
+      stbtt_GetCodepointBitmapBoxSubpixel(&font, text[ch], scale,scale,x_shift,0, &x0,&y0,&x1,&y1);
+      stbtt_MakeCodepointBitmapSubpixel(&font, &screen[baseline + y0][(int) xpos + x0], x1-x0,y1-y0, 79, scale,scale,x_shift,0, text[ch]);
+      // note that this stomps the old data, so where character boxes overlap (e.g. 'lj') it's wrong
+      // because this API is really for baking character bitmaps into textures. if you want to render
+      // a sequence of characters, you really need to render each bitmap to a temp buffer, then
+      // "alpha blend" that into the working buffer
+      xpos += (advance * scale);
+      if (text[ch+1])
+         xpos += scale*stbtt_GetCodepointKernAdvance(&font, text[ch],text[ch+1]);
+      ++ch;
+   }
+
+   for (j=0; j < 20; ++j) {
+      for (i=0; i < 78; ++i)
+         putchar(" .:ioVM@"[screen[j][i]>>5]);
+      putchar('\n');
+   }
+
+   return 0;
+}
+#endif
+
+
+//////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////
+////
+////   INTEGRATION WITH YOUR CODEBASE
+////
+////   The following sections allow you to supply alternate definitions
+////   of C library functions used by stb_truetype, e.g. if you don't
+////   link with the C runtime library.
+
+#ifdef STB_TRUETYPE_IMPLEMENTATION
+   // #define your own (u)stbtt_int8/16/32 before including to override this
+   #ifndef stbtt_uint8
+   typedef unsigned char   stbtt_uint8;
+   typedef signed   char   stbtt_int8;
+   typedef unsigned short  stbtt_uint16;
+   typedef signed   short  stbtt_int16;
+   typedef unsigned int    stbtt_uint32;
+   typedef signed   int    stbtt_int32;
+   #endif
+
+   typedef char stbtt__check_size32[sizeof(stbtt_int32)==4 ? 1 : -1];
+   typedef char stbtt__check_size16[sizeof(stbtt_int16)==2 ? 1 : -1];
+
+   // e.g. #define your own STBTT_ifloor/STBTT_iceil() to avoid math.h
+   #ifndef STBTT_ifloor
+   #include <math.h>
+   #define STBTT_ifloor(x)   ((int) floor(x))
+   #define STBTT_iceil(x)    ((int) ceil(x))
+   #endif
+
+   #ifndef STBTT_sqrt
+   #include <math.h>
+   #define STBTT_sqrt(x)      sqrt(x)
+   #define STBTT_pow(x,y)     pow(x,y)
+   #endif
+
+   #ifndef STBTT_fmod
+   #include <math.h>
+   #define STBTT_fmod(x,y)    fmod(x,y)
+   #endif
+
+   #ifndef STBTT_cos
+   #include <math.h>
+   #define STBTT_cos(x)       cos(x)
+   #define STBTT_acos(x)      acos(x)
+   #endif
+
+   #ifndef STBTT_fabs
+   #include <math.h>
+   #define STBTT_fabs(x)      fabs(x)
+   #endif
+
+   // #define your own functions "STBTT_malloc" / "STBTT_free" to avoid malloc.h
+   #ifndef STBTT_malloc
+   #include <stdlib.h>
+   #define STBTT_malloc(x,u)  ((void)(u),malloc(x))
+   #define STBTT_free(x,u)    ((void)(u),free(x))
+   #endif
+
+   #ifndef STBTT_assert
+   #include <assert.h>
+   #define STBTT_assert(x)    assert(x)
+   #endif
+
+   #ifndef STBTT_strlen
+   #include <string.h>
+   #define STBTT_strlen(x)    strlen(x)
+   #endif
+
+   #ifndef STBTT_memcpy
+   #include <string.h>
+   #define STBTT_memcpy       memcpy
+   #define STBTT_memset       memset
+   #endif
+#endif
+
+///////////////////////////////////////////////////////////////////////////////
+///////////////////////////////////////////////////////////////////////////////
+////
+////   INTERFACE
+////
+////
+
+#ifndef __STB_INCLUDE_STB_TRUETYPE_H__
+#define __STB_INCLUDE_STB_TRUETYPE_H__
+
+#ifdef STBTT_STATIC
+#define STBTT_DEF static
+#else
+#define STBTT_DEF extern
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// private structure
+typedef struct
+{
+   unsigned char *data;
+   int cursor;
+   int size;
+} stbtt__buf;
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// TEXTURE BAKING API
+//
+// If you use this API, you only have to call two functions ever.
+//
+
+typedef struct
+{
+   unsigned short x0,y0,x1,y1; // coordinates of bbox in bitmap
+   float xoff,yoff,xadvance;
+} stbtt_bakedchar;
+
+STBTT_DEF int stbtt_BakeFontBitmap(const unsigned char *data, int offset,  // font location (use offset=0 for plain .ttf)
+                                float pixel_height,                     // height of font in pixels
+                                unsigned char *pixels, int pw, int ph,  // bitmap to be filled in
+                                int first_char, int num_chars,          // characters to bake
+                                stbtt_bakedchar *chardata);             // you allocate this, it's num_chars long
+// if return is positive, the first unused row of the bitmap
+// if return is negative, returns the negative of the number of characters that fit
+// if return is 0, no characters fit and no rows were used
+// This uses a very crappy packing.
+
+typedef struct
+{
+   float x0,y0,s0,t0; // top-left
+   float x1,y1,s1,t1; // bottom-right
+} stbtt_aligned_quad;
+
+STBTT_DEF void stbtt_GetBakedQuad(const stbtt_bakedchar *chardata, int pw, int ph,  // same data as above
+                               int char_index,             // character to display
+                               float *xpos, float *ypos,   // pointers to current position in screen pixel space
+                               stbtt_aligned_quad *q,      // output: quad to draw
+                               int opengl_fillrule);       // true if opengl fill rule; false if DX9 or earlier
+// Call GetBakedQuad with char_index = 'character - first_char', and it
+// creates the quad you need to draw and advances the current position.
+//
+// The coordinate system used assumes y increases downwards.
+//
+// Characters will extend both above and below the current position;
+// see discussion of "BASELINE" above.
+//
+// It's inefficient; you might want to c&p it and optimize it.
+
+STBTT_DEF void stbtt_GetScaledFontVMetrics(const unsigned char *fontdata, int index, float size, float *ascent, float *descent, float *lineGap);
+// Query the font vertical metrics without having to create a font first.
+
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// NEW TEXTURE BAKING API
+//
+// This provides options for packing multiple fonts into one atlas, not
+// perfectly but better than nothing.
+
+typedef struct
+{
+   unsigned short x0,y0,x1,y1; // coordinates of bbox in bitmap
+   float xoff,yoff,xadvance;
+   float xoff2,yoff2;
+} stbtt_packedchar;
+
+typedef struct stbtt_pack_context stbtt_pack_context;
+typedef struct stbtt_fontinfo stbtt_fontinfo;
+#ifndef STB_RECT_PACK_VERSION
+typedef struct stbrp_rect stbrp_rect;
+#endif
+
+STBTT_DEF int  stbtt_PackBegin(stbtt_pack_context *spc, unsigned char *pixels, int width, int height, int stride_in_bytes, int padding, void *alloc_context);
+// Initializes a packing context stored in the passed-in stbtt_pack_context.
+// Future calls using this context will pack characters into the bitmap passed
+// in here: a 1-channel bitmap that is width * height. stride_in_bytes is
+// the distance from one row to the next (or 0 to mean they are packed tightly
+// together). "padding" is the amount of padding to leave between each
+// character (normally you want '1' for bitmaps you'll use as textures with
+// bilinear filtering).
+//
+// Returns 0 on failure, 1 on success.
+
+STBTT_DEF void stbtt_PackEnd  (stbtt_pack_context *spc);
+// Cleans up the packing context and frees all memory.
+
+#define STBTT_POINT_SIZE(x)   (-(x))
+
+STBTT_DEF int  stbtt_PackFontRange(stbtt_pack_context *spc, const unsigned char *fontdata, int font_index, float font_size,
+                                int first_unicode_char_in_range, int num_chars_in_range, stbtt_packedchar *chardata_for_range);
+// Creates character bitmaps from the font_index'th font found in fontdata (use
+// font_index=0 if you don't know what that is). It creates num_chars_in_range
+// bitmaps for characters with unicode values starting at first_unicode_char_in_range
+// and increasing. Data for how to render them is stored in chardata_for_range;
+// pass these to stbtt_GetPackedQuad to get back renderable quads.
+//
+// font_size is the full height of the character from ascender to descender,
+// as computed by stbtt_ScaleForPixelHeight. To use a point size as computed
+// by stbtt_ScaleForMappingEmToPixels, wrap the point size in STBTT_POINT_SIZE()
+// and pass that result as 'font_size':
+//       ...,                  20 , ... // font max minus min y is 20 pixels tall
+//       ..., STBTT_POINT_SIZE(20), ... // 'M' is 20 pixels tall
+
+typedef struct
+{
+   float font_size;
+   int first_unicode_codepoint_in_range;  // if non-zero, then the chars are continuous, and this is the first codepoint
+   int *array_of_unicode_codepoints;       // if non-zero, then this is an array of unicode codepoints
+   int num_chars;
+   stbtt_packedchar *chardata_for_range; // output
+   unsigned char h_oversample, v_oversample; // don't set these, they're used internally
+} stbtt_pack_range;
+
+STBTT_DEF int  stbtt_PackFontRanges(stbtt_pack_context *spc, const unsigned char *fontdata, int font_index, stbtt_pack_range *ranges, int num_ranges);
+// Creates character bitmaps from multiple ranges of characters stored in
+// ranges. This will usually create a better-packed bitmap than multiple
+// calls to stbtt_PackFontRange. Note that you can call this multiple
+// times within a single PackBegin/PackEnd.
+
+STBTT_DEF void stbtt_PackSetOversampling(stbtt_pack_context *spc, unsigned int h_oversample, unsigned int v_oversample);
+// Oversampling a font increases the quality by allowing higher-quality subpixel
+// positioning, and is especially valuable at smaller text sizes.
+//
+// This function sets the amount of oversampling for all following calls to
+// stbtt_PackFontRange(s) or stbtt_PackFontRangesGatherRects for a given
+// pack context. The default (no oversampling) is achieved by h_oversample=1
+// and v_oversample=1. The total number of pixels required is
+// h_oversample*v_oversample larger than the default; for example, 2x2
+// oversampling requires 4x the storage of 1x1. For best results, render
+// oversampled textures with bilinear filtering. Look at the readme in
+// stb/tests/oversample for information about oversampled fonts
+//
+// To use with PackFontRangesGather etc., you must set it before calls
+// call to PackFontRangesGatherRects.
+
+STBTT_DEF void stbtt_PackSetSkipMissingCodepoints(stbtt_pack_context *spc, int skip);
+// If skip != 0, this tells stb_truetype to skip any codepoints for which
+// there is no corresponding glyph. If skip=0, which is the default, then
+// codepoints without a glyph recived the font's "missing character" glyph,
+// typically an empty box by convention.
+
+STBTT_DEF void stbtt_GetPackedQuad(const stbtt_packedchar *chardata, int pw, int ph,  // same data as above
+                               int char_index,             // character to display
+                               float *xpos, float *ypos,   // pointers to current position in screen pixel space
+                               stbtt_aligned_quad *q,      // output: quad to draw
+                               int align_to_integer);
+
+STBTT_DEF int  stbtt_PackFontRangesGatherRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects);
+STBTT_DEF void stbtt_PackFontRangesPackRects(stbtt_pack_context *spc, stbrp_rect *rects, int num_rects);
+STBTT_DEF int  stbtt_PackFontRangesRenderIntoRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects);
+// Calling these functions in sequence is roughly equivalent to calling
+// stbtt_PackFontRanges(). If you more control over the packing of multiple
+// fonts, or if you want to pack custom data into a font texture, take a look
+// at the source to of stbtt_PackFontRanges() and create a custom version 
+// using these functions, e.g. call GatherRects multiple times,
+// building up a single array of rects, then call PackRects once,
+// then call RenderIntoRects repeatedly. This may result in a
+// better packing than calling PackFontRanges multiple times
+// (or it may not).
+
+// this is an opaque structure that you shouldn't mess with which holds
+// all the context needed from PackBegin to PackEnd.
+struct stbtt_pack_context {
+   void *user_allocator_context;
+   void *pack_info;
+   int   width;
+   int   height;
+   int   stride_in_bytes;
+   int   padding;
+   int   skip_missing;
+   unsigned int   h_oversample, v_oversample;
+   unsigned char *pixels;
+   void  *nodes;
+};
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// FONT LOADING
+//
+//
+
+STBTT_DEF int stbtt_GetNumberOfFonts(const unsigned char *data);
+// This function will determine the number of fonts in a font file.  TrueType
+// collection (.ttc) files may contain multiple fonts, while TrueType font
+// (.ttf) files only contain one font. The number of fonts can be used for
+// indexing with the previous function where the index is between zero and one
+// less than the total fonts. If an error occurs, -1 is returned.
+
+STBTT_DEF int stbtt_GetFontOffsetForIndex(const unsigned char *data, int index);
+// Each .ttf/.ttc file may have more than one font. Each font has a sequential
+// index number starting from 0. Call this function to get the font offset for
+// a given index; it returns -1 if the index is out of range. A regular .ttf
+// file will only define one font and it always be at offset 0, so it will
+// return '0' for index 0, and -1 for all other indices.
+
+// The following structure is defined publicly so you can declare one on
+// the stack or as a global or etc, but you should treat it as opaque.
+struct stbtt_fontinfo
+{
+   void           * userdata;
+   unsigned char  * data;              // pointer to .ttf file
+   int              fontstart;         // offset of start of font
+
+   int numGlyphs;                     // number of glyphs, needed for range checking
+
+   int loca,head,glyf,hhea,hmtx,kern,gpos; // table locations as offset from start of .ttf
+   int index_map;                     // a cmap mapping for our chosen character encoding
+   int indexToLocFormat;              // format needed to map from glyph index to glyph
+
+   stbtt__buf cff;                    // cff font data
+   stbtt__buf charstrings;            // the charstring index
+   stbtt__buf gsubrs;                 // global charstring subroutines index
+   stbtt__buf subrs;                  // private charstring subroutines index
+   stbtt__buf fontdicts;              // array of font dicts
+   stbtt__buf fdselect;               // map from glyph to fontdict
+};
+
+STBTT_DEF int stbtt_InitFont(stbtt_fontinfo *info, const unsigned char *data, int offset);
+// Given an offset into the file that defines a font, this function builds
+// the necessary cached info for the rest of the system. You must allocate
+// the stbtt_fontinfo yourself, and stbtt_InitFont will fill it out. You don't
+// need to do anything special to free it, because the contents are pure
+// value data with no additional data structures. Returns 0 on failure.
+
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// CHARACTER TO GLYPH-INDEX CONVERSIOn
+
+STBTT_DEF int stbtt_FindGlyphIndex(const stbtt_fontinfo *info, int unicode_codepoint);
+// If you're going to perform multiple operations on the same character
+// and you want a speed-up, call this function with the character you're
+// going to process, then use glyph-based functions instead of the
+// codepoint-based functions.
+// Returns 0 if the character codepoint is not defined in the font.
+
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// CHARACTER PROPERTIES
+//
+
+STBTT_DEF float stbtt_ScaleForPixelHeight(const stbtt_fontinfo *info, float pixels);
+// computes a scale factor to produce a font whose "height" is 'pixels' tall.
+// Height is measured as the distance from the highest ascender to the lowest
+// descender; in other words, it's equivalent to calling stbtt_GetFontVMetrics
+// and computing:
+//       scale = pixels / (ascent - descent)
+// so if you prefer to measure height by the ascent only, use a similar calculation.
+
+STBTT_DEF float stbtt_ScaleForMappingEmToPixels(const stbtt_fontinfo *info, float pixels);
+// computes a scale factor to produce a font whose EM size is mapped to
+// 'pixels' tall. This is probably what traditional APIs compute, but
+// I'm not positive.
+
+STBTT_DEF void stbtt_GetFontVMetrics(const stbtt_fontinfo *info, int *ascent, int *descent, int *lineGap);
+// ascent is the coordinate above the baseline the font extends; descent
+// is the coordinate below the baseline the font extends (i.e. it is typically negative)
+// lineGap is the spacing between one row's descent and the next row's ascent...
+// so you should advance the vertical position by "*ascent - *descent + *lineGap"
+//   these are expressed in unscaled coordinates, so you must multiply by
+//   the scale factor for a given size
+
+STBTT_DEF int  stbtt_GetFontVMetricsOS2(const stbtt_fontinfo *info, int *typoAscent, int *typoDescent, int *typoLineGap);
+// analogous to GetFontVMetrics, but returns the "typographic" values from the OS/2
+// table (specific to MS/Windows TTF files).
+//
+// Returns 1 on success (table present), 0 on failure.
+
+STBTT_DEF void stbtt_GetFontBoundingBox(const stbtt_fontinfo *info, int *x0, int *y0, int *x1, int *y1);
+// the bounding box around all possible characters
+
+STBTT_DEF void stbtt_GetCodepointHMetrics(const stbtt_fontinfo *info, int codepoint, int *advanceWidth, int *leftSideBearing);
+// leftSideBearing is the offset from the current horizontal position to the left edge of the character
+// advanceWidth is the offset from the current horizontal position to the next horizontal position
+//   these are expressed in unscaled coordinates
+
+STBTT_DEF int  stbtt_GetCodepointKernAdvance(const stbtt_fontinfo *info, int ch1, int ch2);
+// an additional amount to add to the 'advance' value between ch1 and ch2
+
+STBTT_DEF int stbtt_GetCodepointBox(const stbtt_fontinfo *info, int codepoint, int *x0, int *y0, int *x1, int *y1);
+// Gets the bounding box of the visible part of the glyph, in unscaled coordinates
+
+STBTT_DEF void stbtt_GetGlyphHMetrics(const stbtt_fontinfo *info, int glyph_index, int *advanceWidth, int *leftSideBearing);
+STBTT_DEF int  stbtt_GetGlyphKernAdvance(const stbtt_fontinfo *info, int glyph1, int glyph2);
+STBTT_DEF int  stbtt_GetGlyphBox(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1);
+// as above, but takes one or more glyph indices for greater efficiency
+
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// GLYPH SHAPES (you probably don't need these, but they have to go before
+// the bitmaps for C declaration-order reasons)
+//
+
+#ifndef STBTT_vmove // you can predefine these to use different values (but why?)
+   enum {
+      STBTT_vmove=1,
+      STBTT_vline,
+      STBTT_vcurve,
+      STBTT_vcubic
+   };
+#endif
+
+#ifndef stbtt_vertex // you can predefine this to use different values
+                   // (we share this with other code at RAD)
+   #define stbtt_vertex_type short // can't use stbtt_int16 because that's not visible in the header file
+   typedef struct
+   {
+      stbtt_vertex_type x,y,cx,cy,cx1,cy1;
+      unsigned char type,padding;
+   } stbtt_vertex;
+#endif
+
+STBTT_DEF int stbtt_IsGlyphEmpty(const stbtt_fontinfo *info, int glyph_index);
+// returns non-zero if nothing is drawn for this glyph
+
+STBTT_DEF int stbtt_GetCodepointShape(const stbtt_fontinfo *info, int unicode_codepoint, stbtt_vertex **vertices);
+STBTT_DEF int stbtt_GetGlyphShape(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **vertices);
+// returns # of vertices and fills *vertices with the pointer to them
+//   these are expressed in "unscaled" coordinates
+//
+// The shape is a series of contours. Each one starts with
+// a STBTT_moveto, then consists of a series of mixed
+// STBTT_lineto and STBTT_curveto segments. A lineto
+// draws a line from previous endpoint to its x,y; a curveto
+// draws a quadratic bezier from previous endpoint to
+// its x,y, using cx,cy as the bezier control point.
+
+STBTT_DEF void stbtt_FreeShape(const stbtt_fontinfo *info, stbtt_vertex *vertices);
+// frees the data allocated above
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// BITMAP RENDERING
+//
+
+STBTT_DEF void stbtt_FreeBitmap(unsigned char *bitmap, void *userdata);
+// frees the bitmap allocated below
+
+STBTT_DEF unsigned char *stbtt_GetCodepointBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int codepoint, int *width, int *height, int *xoff, int *yoff);
+// allocates a large-enough single-channel 8bpp bitmap and renders the
+// specified character/glyph at the specified scale into it, with
+// antialiasing. 0 is no coverage (transparent), 255 is fully covered (opaque).
+// *width & *height are filled out with the width & height of the bitmap,
+// which is stored left-to-right, top-to-bottom.
+//
+// xoff/yoff are the offset it pixel space from the glyph origin to the top-left of the bitmap
+
+STBTT_DEF unsigned char *stbtt_GetCodepointBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint, int *width, int *height, int *xoff, int *yoff);
+// the same as stbtt_GetCodepoitnBitmap, but you can specify a subpixel
+// shift for the character
+
+STBTT_DEF void stbtt_MakeCodepointBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int codepoint);
+// the same as stbtt_GetCodepointBitmap, but you pass in storage for the bitmap
+// in the form of 'output', with row spacing of 'out_stride' bytes. the bitmap
+// is clipped to out_w/out_h bytes. Call stbtt_GetCodepointBitmapBox to get the
+// width and height and positioning info for it first.
+
+STBTT_DEF void stbtt_MakeCodepointBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint);
+// same as stbtt_MakeCodepointBitmap, but you can specify a subpixel
+// shift for the character
+
+STBTT_DEF void stbtt_MakeCodepointBitmapSubpixelPrefilter(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int oversample_x, int oversample_y, float *sub_x, float *sub_y, int codepoint);
+// same as stbtt_MakeCodepointBitmapSubpixel, but prefiltering
+// is performed (see stbtt_PackSetOversampling)
+
+STBTT_DEF void stbtt_GetCodepointBitmapBox(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1);
+// get the bbox of the bitmap centered around the glyph origin; so the
+// bitmap width is ix1-ix0, height is iy1-iy0, and location to place
+// the bitmap top left is (leftSideBearing*scale,iy0).
+// (Note that the bitmap uses y-increases-down, but the shape uses
+// y-increases-up, so CodepointBitmapBox and CodepointBox are inverted.)
+
+STBTT_DEF void stbtt_GetCodepointBitmapBoxSubpixel(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1);
+// same as stbtt_GetCodepointBitmapBox, but you can specify a subpixel
+// shift for the character
+
+// the following functions are equivalent to the above functions, but operate
+// on glyph indices instead of Unicode codepoints (for efficiency)
+STBTT_DEF unsigned char *stbtt_GetGlyphBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int glyph, int *width, int *height, int *xoff, int *yoff);
+STBTT_DEF unsigned char *stbtt_GetGlyphBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int glyph, int *width, int *height, int *xoff, int *yoff);
+STBTT_DEF void stbtt_MakeGlyphBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int glyph);
+STBTT_DEF void stbtt_MakeGlyphBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int glyph);
+STBTT_DEF void stbtt_MakeGlyphBitmapSubpixelPrefilter(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int oversample_x, int oversample_y, float *sub_x, float *sub_y, int glyph);
+STBTT_DEF void stbtt_GetGlyphBitmapBox(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1);
+STBTT_DEF void stbtt_GetGlyphBitmapBoxSubpixel(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y,float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1);
+
+
+// @TODO: don't expose this structure
+typedef struct
+{
+   int w,h,stride;
+   unsigned char *pixels;
+} stbtt__bitmap;
+
+// rasterize a shape with quadratic beziers into a bitmap
+STBTT_DEF void stbtt_Rasterize(stbtt__bitmap *result,        // 1-channel bitmap to draw into
+                               float flatness_in_pixels,     // allowable error of curve in pixels
+                               stbtt_vertex *vertices,       // array of vertices defining shape
+                               int num_verts,                // number of vertices in above array
+                               float scale_x, float scale_y, // scale applied to input vertices
+                               float shift_x, float shift_y, // translation applied to input vertices
+                               int x_off, int y_off,         // another translation applied to input
+                               int invert,                   // if non-zero, vertically flip shape
+                               void *userdata);              // context for to STBTT_MALLOC
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// Signed Distance Function (or Field) rendering
+
+STBTT_DEF void stbtt_FreeSDF(unsigned char *bitmap, void *userdata);
+// frees the SDF bitmap allocated below
+
+STBTT_DEF unsigned char * stbtt_GetGlyphSDF(const stbtt_fontinfo *info, float scale, int glyph, int padding, unsigned char onedge_value, float pixel_dist_scale, int *width, int *height, int *xoff, int *yoff);
+STBTT_DEF unsigned char * stbtt_GetCodepointSDF(const stbtt_fontinfo *info, float scale, int codepoint, int padding, unsigned char onedge_value, float pixel_dist_scale, int *width, int *height, int *xoff, int *yoff);
+// These functions compute a discretized SDF field for a single character, suitable for storing
+// in a single-channel texture, sampling with bilinear filtering, and testing against
+// larger than some threshold to produce scalable fonts.
+//        info              --  the font
+//        scale             --  controls the size of the resulting SDF bitmap, same as it would be creating a regular bitmap
+//        glyph/codepoint   --  the character to generate the SDF for
+//        padding           --  extra "pixels" around the character which are filled with the distance to the character (not 0),
+//                                 which allows effects like bit outlines
+//        onedge_value      --  value 0-255 to test the SDF against to reconstruct the character (i.e. the isocontour of the character)
+//        pixel_dist_scale  --  what value the SDF should increase by when moving one SDF "pixel" away from the edge (on the 0..255 scale)
+//                                 if positive, > onedge_value is inside; if negative, < onedge_value is inside
+//        width,height      --  output height & width of the SDF bitmap (including padding)
+//        xoff,yoff         --  output origin of the character
+//        return value      --  a 2D array of bytes 0..255, width*height in size
+//
+// pixel_dist_scale & onedge_value are a scale & bias that allows you to make
+// optimal use of the limited 0..255 for your application, trading off precision
+// and special effects. SDF values outside the range 0..255 are clamped to 0..255.
+//
+// Example:
+//      scale = stbtt_ScaleForPixelHeight(22)
+//      padding = 5
+//      onedge_value = 180
+//      pixel_dist_scale = 180/5.0 = 36.0
+//
+//      This will create an SDF bitmap in which the character is about 22 pixels
+//      high but the whole bitmap is about 22+5+5=32 pixels high. To produce a filled
+//      shape, sample the SDF at each pixel and fill the pixel if the SDF value
+//      is greater than or equal to 180/255. (You'll actually want to antialias,
+//      which is beyond the scope of this example.) Additionally, you can compute
+//      offset outlines (e.g. to stroke the character border inside & outside,
+//      or only outside). For example, to fill outside the character up to 3 SDF
+//      pixels, you would compare against (180-36.0*3)/255 = 72/255. The above
+//      choice of variables maps a range from 5 pixels outside the shape to
+//      2 pixels inside the shape to 0..255; this is intended primarily for apply
+//      outside effects only (the interior range is needed to allow proper
+//      antialiasing of the font at *smaller* sizes)
+//
+// The function computes the SDF analytically at each SDF pixel, not by e.g.
+// building a higher-res bitmap and approximating it. In theory the quality
+// should be as high as possible for an SDF of this size & representation, but
+// unclear if this is true in practice (perhaps building a higher-res bitmap
+// and computing from that can allow drop-out prevention).
+//
+// The algorithm has not been optimized at all, so expect it to be slow
+// if computing lots of characters or very large sizes. 
+
+
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// Finding the right font...
+//
+// You should really just solve this offline, keep your own tables
+// of what font is what, and don't try to get it out of the .ttf file.
+// That's because getting it out of the .ttf file is really hard, because
+// the names in the file can appear in many possible encodings, in many
+// possible languages, and e.g. if you need a case-insensitive comparison,
+// the details of that depend on the encoding & language in a complex way
+// (actually underspecified in truetype, but also gigantic).
+//
+// But you can use the provided functions in two possible ways:
+//     stbtt_FindMatchingFont() will use *case-sensitive* comparisons on
+//             unicode-encoded names to try to find the font you want;
+//             you can run this before calling stbtt_InitFont()
+//
+//     stbtt_GetFontNameString() lets you get any of the various strings
+//             from the file yourself and do your own comparisons on them.
+//             You have to have called stbtt_InitFont() first.
+
+
+STBTT_DEF int stbtt_FindMatchingFont(const unsigned char *fontdata, const char *name, int flags);
+// returns the offset (not index) of the font that matches, or -1 if none
+//   if you use STBTT_MACSTYLE_DONTCARE, use a font name like "Arial Bold".
+//   if you use any other flag, use a font name like "Arial"; this checks
+//     the 'macStyle' header field; i don't know if fonts set this consistently
+#define STBTT_MACSTYLE_DONTCARE     0
+#define STBTT_MACSTYLE_BOLD         1
+#define STBTT_MACSTYLE_ITALIC       2
+#define STBTT_MACSTYLE_UNDERSCORE   4
+#define STBTT_MACSTYLE_NONE         8   // <= not same as 0, this makes us check the bitfield is 0
+
+STBTT_DEF int stbtt_CompareUTF8toUTF16_bigendian(const char *s1, int len1, const char *s2, int len2);
+// returns 1/0 whether the first string interpreted as utf8 is identical to
+// the second string interpreted as big-endian utf16... useful for strings from next func
+
+STBTT_DEF const char *stbtt_GetFontNameString(const stbtt_fontinfo *font, int *length, int platformID, int encodingID, int languageID, int nameID);
+// returns the string (which may be big-endian double byte, e.g. for unicode)
+// and puts the length in bytes in *length.
+//
+// some of the values for the IDs are below; for more see the truetype spec:
+//     http://developer.apple.com/textfonts/TTRefMan/RM06/Chap6name.html
+//     http://www.microsoft.com/typography/otspec/name.htm
+
+enum { // platformID
+   STBTT_PLATFORM_ID_UNICODE   =0,
+   STBTT_PLATFORM_ID_MAC       =1,
+   STBTT_PLATFORM_ID_ISO       =2,
+   STBTT_PLATFORM_ID_MICROSOFT =3
+};
+
+enum { // encodingID for STBTT_PLATFORM_ID_UNICODE
+   STBTT_UNICODE_EID_UNICODE_1_0    =0,
+   STBTT_UNICODE_EID_UNICODE_1_1    =1,
+   STBTT_UNICODE_EID_ISO_10646      =2,
+   STBTT_UNICODE_EID_UNICODE_2_0_BMP=3,
+   STBTT_UNICODE_EID_UNICODE_2_0_FULL=4
+};
+
+enum { // encodingID for STBTT_PLATFORM_ID_MICROSOFT
+   STBTT_MS_EID_SYMBOL        =0,
+   STBTT_MS_EID_UNICODE_BMP   =1,
+   STBTT_MS_EID_SHIFTJIS      =2,
+   STBTT_MS_EID_UNICODE_FULL  =10
+};
+
+enum { // encodingID for STBTT_PLATFORM_ID_MAC; same as Script Manager codes
+   STBTT_MAC_EID_ROMAN        =0,   STBTT_MAC_EID_ARABIC       =4,
+   STBTT_MAC_EID_JAPANESE     =1,   STBTT_MAC_EID_HEBREW       =5,
+   STBTT_MAC_EID_CHINESE_TRAD =2,   STBTT_MAC_EID_GREEK        =6,
+   STBTT_MAC_EID_KOREAN       =3,   STBTT_MAC_EID_RUSSIAN      =7
+};
+
+enum { // languageID for STBTT_PLATFORM_ID_MICROSOFT; same as LCID...
+       // problematic because there are e.g. 16 english LCIDs and 16 arabic LCIDs
+   STBTT_MS_LANG_ENGLISH     =0x0409,   STBTT_MS_LANG_ITALIAN     =0x0410,
+   STBTT_MS_LANG_CHINESE     =0x0804,   STBTT_MS_LANG_JAPANESE    =0x0411,
+   STBTT_MS_LANG_DUTCH       =0x0413,   STBTT_MS_LANG_KOREAN      =0x0412,
+   STBTT_MS_LANG_FRENCH      =0x040c,   STBTT_MS_LANG_RUSSIAN     =0x0419,
+   STBTT_MS_LANG_GERMAN      =0x0407,   STBTT_MS_LANG_SPANISH     =0x0409,
+   STBTT_MS_LANG_HEBREW      =0x040d,   STBTT_MS_LANG_SWEDISH     =0x041D
+};
+
+enum { // languageID for STBTT_PLATFORM_ID_MAC
+   STBTT_MAC_LANG_ENGLISH      =0 ,   STBTT_MAC_LANG_JAPANESE     =11,
+   STBTT_MAC_LANG_ARABIC       =12,   STBTT_MAC_LANG_KOREAN       =23,
+   STBTT_MAC_LANG_DUTCH        =4 ,   STBTT_MAC_LANG_RUSSIAN      =32,
+   STBTT_MAC_LANG_FRENCH       =1 ,   STBTT_MAC_LANG_SPANISH      =6 ,
+   STBTT_MAC_LANG_GERMAN       =2 ,   STBTT_MAC_LANG_SWEDISH      =5 ,
+   STBTT_MAC_LANG_HEBREW       =10,   STBTT_MAC_LANG_CHINESE_SIMPLIFIED =33,
+   STBTT_MAC_LANG_ITALIAN      =3 ,   STBTT_MAC_LANG_CHINESE_TRAD =19
+};
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // __STB_INCLUDE_STB_TRUETYPE_H__
+
+///////////////////////////////////////////////////////////////////////////////
+///////////////////////////////////////////////////////////////////////////////
+////
+////   IMPLEMENTATION
+////
+////
+
+#ifdef STB_TRUETYPE_IMPLEMENTATION
+
+#ifndef STBTT_MAX_OVERSAMPLE
+#define STBTT_MAX_OVERSAMPLE   8
+#endif
+
+#if STBTT_MAX_OVERSAMPLE > 255
+#error "STBTT_MAX_OVERSAMPLE cannot be > 255"
+#endif
+
+typedef int stbtt__test_oversample_pow2[(STBTT_MAX_OVERSAMPLE & (STBTT_MAX_OVERSAMPLE-1)) == 0 ? 1 : -1];
+
+#ifndef STBTT_RASTERIZER_VERSION
+#define STBTT_RASTERIZER_VERSION 2
+#endif
+
+#ifdef _MSC_VER
+#define STBTT__NOTUSED(v)  (void)(v)
+#else
+#define STBTT__NOTUSED(v)  (void)sizeof(v)
+#endif
+
+//////////////////////////////////////////////////////////////////////////
+//
+// stbtt__buf helpers to parse data from file
+//
+
+static stbtt_uint8 stbtt__buf_get8(stbtt__buf *b)
+{
+   if (b->cursor >= b->size)
+      return 0;
+   return b->data[b->cursor++];
+}
+
+static stbtt_uint8 stbtt__buf_peek8(stbtt__buf *b)
+{
+   if (b->cursor >= b->size)
+      return 0;
+   return b->data[b->cursor];
+}
+
+static void stbtt__buf_seek(stbtt__buf *b, int o)
+{
+   STBTT_assert(!(o > b->size || o < 0));
+   b->cursor = (o > b->size || o < 0) ? b->size : o;
+}
+
+static void stbtt__buf_skip(stbtt__buf *b, int o)
+{
+   stbtt__buf_seek(b, b->cursor + o);
+}
+
+static stbtt_uint32 stbtt__buf_get(stbtt__buf *b, int n)
+{
+   stbtt_uint32 v = 0;
+   int i;
+   STBTT_assert(n >= 1 && n <= 4);
+   for (i = 0; i < n; i++)
+      v = (v << 8) | stbtt__buf_get8(b);
+   return v;
+}
+
+static stbtt__buf stbtt__new_buf(const void *p, size_t size)
+{
+   stbtt__buf r;
+   STBTT_assert(size < 0x40000000);
+   r.data = (stbtt_uint8*) p;
+   r.size = (int) size;
+   r.cursor = 0;
+   return r;
+}
+
+#define stbtt__buf_get16(b)  stbtt__buf_get((b), 2)
+#define stbtt__buf_get32(b)  stbtt__buf_get((b), 4)
+
+static stbtt__buf stbtt__buf_range(const stbtt__buf *b, int o, int s)
+{
+   stbtt__buf r = stbtt__new_buf(NULL, 0);
+   if (o < 0 || s < 0 || o > b->size || s > b->size - o) return r;
+   r.data = b->data + o;
+   r.size = s;
+   return r;
+}
+
+static stbtt__buf stbtt__cff_get_index(stbtt__buf *b)
+{
+   int count, start, offsize;
+   start = b->cursor;
+   count = stbtt__buf_get16(b);
+   if (count) {
+      offsize = stbtt__buf_get8(b);
+      STBTT_assert(offsize >= 1 && offsize <= 4);
+      stbtt__buf_skip(b, offsize * count);
+      stbtt__buf_skip(b, stbtt__buf_get(b, offsize) - 1);
+   }
+   return stbtt__buf_range(b, start, b->cursor - start);
+}
+
+static stbtt_uint32 stbtt__cff_int(stbtt__buf *b)
+{
+   int b0 = stbtt__buf_get8(b);
+   if (b0 >= 32 && b0 <= 246)       return b0 - 139;
+   else if (b0 >= 247 && b0 <= 250) return (b0 - 247)*256 + stbtt__buf_get8(b) + 108;
+   else if (b0 >= 251 && b0 <= 254) return -(b0 - 251)*256 - stbtt__buf_get8(b) - 108;
+   else if (b0 == 28)               return stbtt__buf_get16(b);
+   else if (b0 == 29)               return stbtt__buf_get32(b);
+   STBTT_assert(0);
+   return 0;
+}
+
+static void stbtt__cff_skip_operand(stbtt__buf *b) {
+   int v, b0 = stbtt__buf_peek8(b);
+   STBTT_assert(b0 >= 28);
+   if (b0 == 30) {
+      stbtt__buf_skip(b, 1);
+      while (b->cursor < b->size) {
+         v = stbtt__buf_get8(b);
+         if ((v & 0xF) == 0xF || (v >> 4) == 0xF)
+            break;
+      }
+   } else {
+      stbtt__cff_int(b);
+   }
+}
+
+static stbtt__buf stbtt__dict_get(stbtt__buf *b, int key)
+{
+   stbtt__buf_seek(b, 0);
+   while (b->cursor < b->size) {
+      int start = b->cursor, end, op;
+      while (stbtt__buf_peek8(b) >= 28)
+         stbtt__cff_skip_operand(b);
+      end = b->cursor;
+      op = stbtt__buf_get8(b);
+      if (op == 12)  op = stbtt__buf_get8(b) | 0x100;
+      if (op == key) return stbtt__buf_range(b, start, end-start);
+   }
+   return stbtt__buf_range(b, 0, 0);
+}
+
+static void stbtt__dict_get_ints(stbtt__buf *b, int key, int outcount, stbtt_uint32 *out)
+{
+   int i;
+   stbtt__buf operands = stbtt__dict_get(b, key);
+   for (i = 0; i < outcount && operands.cursor < operands.size; i++)
+      out[i] = stbtt__cff_int(&operands);
+}
+
+static int stbtt__cff_index_count(stbtt__buf *b)
+{
+   stbtt__buf_seek(b, 0);
+   return stbtt__buf_get16(b);
+}
+
+static stbtt__buf stbtt__cff_index_get(stbtt__buf b, int i)
+{
+   int count, offsize, start, end;
+   stbtt__buf_seek(&b, 0);
+   count = stbtt__buf_get16(&b);
+   offsize = stbtt__buf_get8(&b);
+   STBTT_assert(i >= 0 && i < count);
+   STBTT_assert(offsize >= 1 && offsize <= 4);
+   stbtt__buf_skip(&b, i*offsize);
+   start = stbtt__buf_get(&b, offsize);
+   end = stbtt__buf_get(&b, offsize);
+   return stbtt__buf_range(&b, 2+(count+1)*offsize+start, end - start);
+}
+
+//////////////////////////////////////////////////////////////////////////
+//
+// accessors to parse data from file
+//
+
+// on platforms that don't allow misaligned reads, if we want to allow
+// truetype fonts that aren't padded to alignment, define ALLOW_UNALIGNED_TRUETYPE
+
+#define ttBYTE(p)     (* (stbtt_uint8 *) (p))
+#define ttCHAR(p)     (* (stbtt_int8 *) (p))
+#define ttFixed(p)    ttLONG(p)
+
+static stbtt_uint16 ttUSHORT(stbtt_uint8 *p) { return p[0]*256 + p[1]; }
+static stbtt_int16 ttSHORT(stbtt_uint8 *p)   { return p[0]*256 + p[1]; }
+static stbtt_uint32 ttULONG(stbtt_uint8 *p)  { return (p[0]<<24) + (p[1]<<16) + (p[2]<<8) + p[3]; }
+static stbtt_int32 ttLONG(stbtt_uint8 *p)    { return (p[0]<<24) + (p[1]<<16) + (p[2]<<8) + p[3]; }
+
+#define stbtt_tag4(p,c0,c1,c2,c3) ((p)[0] == (c0) && (p)[1] == (c1) && (p)[2] == (c2) && (p)[3] == (c3))
+#define stbtt_tag(p,str)           stbtt_tag4(p,str[0],str[1],str[2],str[3])
+
+static int stbtt__isfont(stbtt_uint8 *font)
+{
+   // check the version number
+   if (stbtt_tag4(font, '1',0,0,0))  return 1; // TrueType 1
+   if (stbtt_tag(font, "typ1"))   return 1; // TrueType with type 1 font -- we don't support this!
+   if (stbtt_tag(font, "OTTO"))   return 1; // OpenType with CFF
+   if (stbtt_tag4(font, 0,1,0,0)) return 1; // OpenType 1.0
+   if (stbtt_tag(font, "true"))   return 1; // Apple specification for TrueType fonts
+   return 0;
+}
+
+// @OPTIMIZE: binary search
+static stbtt_uint32 stbtt__find_table(stbtt_uint8 *data, stbtt_uint32 fontstart, const char *tag)
+{
+   stbtt_int32 num_tables = ttUSHORT(data+fontstart+4);
+   stbtt_uint32 tabledir = fontstart + 12;
+   stbtt_int32 i;
+   for (i=0; i < num_tables; ++i) {
+      stbtt_uint32 loc = tabledir + 16*i;
+      if (stbtt_tag(data+loc+0, tag))
+         return ttULONG(data+loc+8);
+   }
+   return 0;
+}
+
+static int stbtt_GetFontOffsetForIndex_internal(unsigned char *font_collection, int index)
+{
+   // if it's just a font, there's only one valid index
+   if (stbtt__isfont(font_collection))
+      return index == 0 ? 0 : -1;
+
+   // check if it's a TTC
+   if (stbtt_tag(font_collection, "ttcf")) {
+      // version 1?
+      if (ttULONG(font_collection+4) == 0x00010000 || ttULONG(font_collection+4) == 0x00020000) {
+         stbtt_int32 n = ttLONG(font_collection+8);
+         if (index >= n)
+            return -1;
+         return ttULONG(font_collection+12+index*4);
+      }
+   }
+   return -1;
+}
+
+static int stbtt_GetNumberOfFonts_internal(unsigned char *font_collection)
+{
+   // if it's just a font, there's only one valid font
+   if (stbtt__isfont(font_collection))
+      return 1;
+
+   // check if it's a TTC
+   if (stbtt_tag(font_collection, "ttcf")) {
+      // version 1?
+      if (ttULONG(font_collection+4) == 0x00010000 || ttULONG(font_collection+4) == 0x00020000) {
+         return ttLONG(font_collection+8);
+      }
+   }
+   return 0;
+}
+
+static stbtt__buf stbtt__get_subrs(stbtt__buf cff, stbtt__buf fontdict)
+{
+   stbtt_uint32 subrsoff = 0, private_loc[2] = { 0, 0 };
+   stbtt__buf pdict;
+   stbtt__dict_get_ints(&fontdict, 18, 2, private_loc);
+   if (!private_loc[1] || !private_loc[0]) return stbtt__new_buf(NULL, 0);
+   pdict = stbtt__buf_range(&cff, private_loc[1], private_loc[0]);
+   stbtt__dict_get_ints(&pdict, 19, 1, &subrsoff);
+   if (!subrsoff) return stbtt__new_buf(NULL, 0);
+   stbtt__buf_seek(&cff, private_loc[1]+subrsoff);
+   return stbtt__cff_get_index(&cff);
+}
+
+static int stbtt_InitFont_internal(stbtt_fontinfo *info, unsigned char *data, int fontstart)
+{
+   stbtt_uint32 cmap, t;
+   stbtt_int32 i,numTables;
+
+   info->data = data;
+   info->fontstart = fontstart;
+   info->cff = stbtt__new_buf(NULL, 0);
+
+   cmap = stbtt__find_table(data, fontstart, "cmap");       // required
+   info->loca = stbtt__find_table(data, fontstart, "loca"); // required
+   info->head = stbtt__find_table(data, fontstart, "head"); // required
+   info->glyf = stbtt__find_table(data, fontstart, "glyf"); // required
+   info->hhea = stbtt__find_table(data, fontstart, "hhea"); // required
+   info->hmtx = stbtt__find_table(data, fontstart, "hmtx"); // required
+   info->kern = stbtt__find_table(data, fontstart, "kern"); // not required
+   info->gpos = stbtt__find_table(data, fontstart, "GPOS"); // not required
+
+   if (!cmap || !info->head || !info->hhea || !info->hmtx)
+      return 0;
+   if (info->glyf) {
+      // required for truetype
+      if (!info->loca) return 0;
+   } else {
+      // initialization for CFF / Type2 fonts (OTF)
+      stbtt__buf b, topdict, topdictidx;
+      stbtt_uint32 cstype = 2, charstrings = 0, fdarrayoff = 0, fdselectoff = 0;
+      stbtt_uint32 cff;
+
+      cff = stbtt__find_table(data, fontstart, "CFF ");
+      if (!cff) return 0;
+
+      info->fontdicts = stbtt__new_buf(NULL, 0);
+      info->fdselect = stbtt__new_buf(NULL, 0);
+
+      // @TODO this should use size from table (not 512MB)
+      info->cff = stbtt__new_buf(data+cff, 512*1024*1024);
+      b = info->cff;
+
+      // read the header
+      stbtt__buf_skip(&b, 2);
+      stbtt__buf_seek(&b, stbtt__buf_get8(&b)); // hdrsize
+
+      // @TODO the name INDEX could list multiple fonts,
+      // but we just use the first one.
+      stbtt__cff_get_index(&b);  // name INDEX
+      topdictidx = stbtt__cff_get_index(&b);
+      topdict = stbtt__cff_index_get(topdictidx, 0);
+      stbtt__cff_get_index(&b);  // string INDEX
+      info->gsubrs = stbtt__cff_get_index(&b);
+
+      stbtt__dict_get_ints(&topdict, 17, 1, &charstrings);
+      stbtt__dict_get_ints(&topdict, 0x100 | 6, 1, &cstype);
+      stbtt__dict_get_ints(&topdict, 0x100 | 36, 1, &fdarrayoff);
+      stbtt__dict_get_ints(&topdict, 0x100 | 37, 1, &fdselectoff);
+      info->subrs = stbtt__get_subrs(b, topdict);
+
+      // we only support Type 2 charstrings
+      if (cstype != 2) return 0;
+      if (charstrings == 0) return 0;
+
+      if (fdarrayoff) {
+         // looks like a CID font
+         if (!fdselectoff) return 0;
+         stbtt__buf_seek(&b, fdarrayoff);
+         info->fontdicts = stbtt__cff_get_index(&b);
+         info->fdselect = stbtt__buf_range(&b, fdselectoff, b.size-fdselectoff);
+      }
+
+      stbtt__buf_seek(&b, charstrings);
+      info->charstrings = stbtt__cff_get_index(&b);
+   }
+
+   t = stbtt__find_table(data, fontstart, "maxp");
+   if (t)
+      info->numGlyphs = ttUSHORT(data+t+4);
+   else
+      info->numGlyphs = 0xffff;
+
+   // find a cmap encoding table we understand *now* to avoid searching
+   // later. (todo: could make this installable)
+   // the same regardless of glyph.
+   numTables = ttUSHORT(data + cmap + 2);
+   info->index_map = 0;
+   for (i=0; i < numTables; ++i) {
+      stbtt_uint32 encoding_record = cmap + 4 + 8 * i;
+      // find an encoding we understand:
+      switch(ttUSHORT(data+encoding_record)) {
+         case STBTT_PLATFORM_ID_MICROSOFT:
+            switch (ttUSHORT(data+encoding_record+2)) {
+               case STBTT_MS_EID_UNICODE_BMP:
+               case STBTT_MS_EID_UNICODE_FULL:
+                  // MS/Unicode
+                  info->index_map = cmap + ttULONG(data+encoding_record+4);
+                  break;
+            }
+            break;
+        case STBTT_PLATFORM_ID_UNICODE:
+            // Mac/iOS has these
+            // all the encodingIDs are unicode, so we don't bother to check it
+            info->index_map = cmap + ttULONG(data+encoding_record+4);
+            break;
+      }
+   }
+   if (info->index_map == 0)
+      return 0;
+
+   info->indexToLocFormat = ttUSHORT(data+info->head + 50);
+   return 1;
+}
+
+STBTT_DEF int stbtt_FindGlyphIndex(const stbtt_fontinfo *info, int unicode_codepoint)
+{
+   stbtt_uint8 *data = info->data;
+   stbtt_uint32 index_map = info->index_map;
+
+   stbtt_uint16 format = ttUSHORT(data + index_map + 0);
+   if (format == 0) { // apple byte encoding
+      stbtt_int32 bytes = ttUSHORT(data + index_map + 2);
+      if (unicode_codepoint < bytes-6)
+         return ttBYTE(data + index_map + 6 + unicode_codepoint);
+      return 0;
+   } else if (format == 6) {
+      stbtt_uint32 first = ttUSHORT(data + index_map + 6);
+      stbtt_uint32 count = ttUSHORT(data + index_map + 8);
+      if ((stbtt_uint32) unicode_codepoint >= first && (stbtt_uint32) unicode_codepoint < first+count)
+         return ttUSHORT(data + index_map + 10 + (unicode_codepoint - first)*2);
+      return 0;
+   } else if (format == 2) {
+      STBTT_assert(0); // @TODO: high-byte mapping for japanese/chinese/korean
+      return 0;
+   } else if (format == 4) { // standard mapping for windows fonts: binary search collection of ranges
+      stbtt_uint16 segcount = ttUSHORT(data+index_map+6) >> 1;
+      stbtt_uint16 searchRange = ttUSHORT(data+index_map+8) >> 1;
+      stbtt_uint16 entrySelector = ttUSHORT(data+index_map+10);
+      stbtt_uint16 rangeShift = ttUSHORT(data+index_map+12) >> 1;
+
+      // do a binary search of the segments
+      stbtt_uint32 endCount = index_map + 14;
+      stbtt_uint32 search = endCount;
+
+      if (unicode_codepoint > 0xffff)
+         return 0;
+
+      // they lie from endCount .. endCount + segCount
+      // but searchRange is the nearest power of two, so...
+      if (unicode_codepoint >= ttUSHORT(data + search + rangeShift*2))
+         search += rangeShift*2;
+
+      // now decrement to bias correctly to find smallest
+      search -= 2;
+      while (entrySelector) {
+         stbtt_uint16 end;
+         searchRange >>= 1;
+         end = ttUSHORT(data + search + searchRange*2);
+         if (unicode_codepoint > end)
+            search += searchRange*2;
+         --entrySelector;
+      }
+      search += 2;
+
+      {
+         stbtt_uint16 offset, start;
+         stbtt_uint16 item = (stbtt_uint16) ((search - endCount) >> 1);
+
+         STBTT_assert(unicode_codepoint <= ttUSHORT(data + endCount + 2*item));
+         start = ttUSHORT(data + index_map + 14 + segcount*2 + 2 + 2*item);
+         if (unicode_codepoint < start)
+            return 0;
+
+         offset = ttUSHORT(data + index_map + 14 + segcount*6 + 2 + 2*item);
+         if (offset == 0)
+            return (stbtt_uint16) (unicode_codepoint + ttSHORT(data + index_map + 14 + segcount*4 + 2 + 2*item));
+
+         return ttUSHORT(data + offset + (unicode_codepoint-start)*2 + index_map + 14 + segcount*6 + 2 + 2*item);
+      }
+   } else if (format == 12 || format == 13) {
+      stbtt_uint32 ngroups = ttULONG(data+index_map+12);
+      stbtt_int32 low,high;
+      low = 0; high = (stbtt_int32)ngroups;
+      // Binary search the right group.
+      while (low < high) {
+         stbtt_int32 mid = low + ((high-low) >> 1); // rounds down, so low <= mid < high
+         stbtt_uint32 start_char = ttULONG(data+index_map+16+mid*12);
+         stbtt_uint32 end_char = ttULONG(data+index_map+16+mid*12+4);
+         if ((stbtt_uint32) unicode_codepoint < start_char)
+            high = mid;
+         else if ((stbtt_uint32) unicode_codepoint > end_char)
+            low = mid+1;
+         else {
+            stbtt_uint32 start_glyph = ttULONG(data+index_map+16+mid*12+8);
+            if (format == 12)
+               return start_glyph + unicode_codepoint-start_char;
+            else // format == 13
+               return start_glyph;
+         }
+      }
+      return 0; // not found
+   }
+   // @TODO
+   STBTT_assert(0);
+   return 0;
+}
+
+STBTT_DEF int stbtt_GetCodepointShape(const stbtt_fontinfo *info, int unicode_codepoint, stbtt_vertex **vertices)
+{
+   return stbtt_GetGlyphShape(info, stbtt_FindGlyphIndex(info, unicode_codepoint), vertices);
+}
+
+static void stbtt_setvertex(stbtt_vertex *v, stbtt_uint8 type, stbtt_int32 x, stbtt_int32 y, stbtt_int32 cx, stbtt_int32 cy)
+{
+   v->type = type;
+   v->x = (stbtt_int16) x;
+   v->y = (stbtt_int16) y;
+   v->cx = (stbtt_int16) cx;
+   v->cy = (stbtt_int16) cy;
+}
+
+static int stbtt__GetGlyfOffset(const stbtt_fontinfo *info, int glyph_index)
+{
+   int g1,g2;
+
+   STBTT_assert(!info->cff.size);
+
+   if (glyph_index >= info->numGlyphs) return -1; // glyph index out of range
+   if (info->indexToLocFormat >= 2)    return -1; // unknown index->glyph map format
+
+   if (info->indexToLocFormat == 0) {
+      g1 = info->glyf + ttUSHORT(info->data + info->loca + glyph_index * 2) * 2;
+      g2 = info->glyf + ttUSHORT(info->data + info->loca + glyph_index * 2 + 2) * 2;
+   } else {
+      g1 = info->glyf + ttULONG (info->data + info->loca + glyph_index * 4);
+      g2 = info->glyf + ttULONG (info->data + info->loca + glyph_index * 4 + 4);
+   }
+
+   return g1==g2 ? -1 : g1; // if length is 0, return -1
+}
+
+static int stbtt__GetGlyphInfoT2(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1);
+
+STBTT_DEF int stbtt_GetGlyphBox(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1)
+{
+   if (info->cff.size) {
+      stbtt__GetGlyphInfoT2(info, glyph_index, x0, y0, x1, y1);
+   } else {
+      int g = stbtt__GetGlyfOffset(info, glyph_index);
+      if (g < 0) return 0;
+
+      if (x0) *x0 = ttSHORT(info->data + g + 2);
+      if (y0) *y0 = ttSHORT(info->data + g + 4);
+      if (x1) *x1 = ttSHORT(info->data + g + 6);
+      if (y1) *y1 = ttSHORT(info->data + g + 8);
+   }
+   return 1;
+}
+
+STBTT_DEF int stbtt_GetCodepointBox(const stbtt_fontinfo *info, int codepoint, int *x0, int *y0, int *x1, int *y1)
+{
+   return stbtt_GetGlyphBox(info, stbtt_FindGlyphIndex(info,codepoint), x0,y0,x1,y1);
+}
+
+STBTT_DEF int stbtt_IsGlyphEmpty(const stbtt_fontinfo *info, int glyph_index)
+{
+   stbtt_int16 numberOfContours;
+   int g;
+   if (info->cff.size)
+      return stbtt__GetGlyphInfoT2(info, glyph_index, NULL, NULL, NULL, NULL) == 0;
+   g = stbtt__GetGlyfOffset(info, glyph_index);
+   if (g < 0) return 1;
+   numberOfContours = ttSHORT(info->data + g);
+   return numberOfContours == 0;
+}
+
+static int stbtt__close_shape(stbtt_vertex *vertices, int num_vertices, int was_off, int start_off,
+    stbtt_int32 sx, stbtt_int32 sy, stbtt_int32 scx, stbtt_int32 scy, stbtt_int32 cx, stbtt_int32 cy)
+{
+   if (start_off) {
+      if (was_off)
+         stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, (cx+scx)>>1, (cy+scy)>>1, cx,cy);
+      stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, sx,sy,scx,scy);
+   } else {
+      if (was_off)
+         stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve,sx,sy,cx,cy);
+      else
+         stbtt_setvertex(&vertices[num_vertices++], STBTT_vline,sx,sy,0,0);
+   }
+   return num_vertices;
+}
+
+static int stbtt__GetGlyphShapeTT(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **pvertices)
+{
+   stbtt_int16 numberOfContours;
+   stbtt_uint8 *endPtsOfContours;
+   stbtt_uint8 *data = info->data;
+   stbtt_vertex *vertices=0;
+   int num_vertices=0;
+   int g = stbtt__GetGlyfOffset(info, glyph_index);
+
+   *pvertices = NULL;
+
+   if (g < 0) return 0;
+
+   numberOfContours = ttSHORT(data + g);
+
+   if (numberOfContours > 0) {
+      stbtt_uint8 flags=0,flagcount;
+      stbtt_int32 ins, i,j=0,m,n, next_move, was_off=0, off, start_off=0;
+      stbtt_int32 x,y,cx,cy,sx,sy, scx,scy;
+      stbtt_uint8 *points;
+      endPtsOfContours = (data + g + 10);
+      ins = ttUSHORT(data + g + 10 + numberOfContours * 2);
+      points = data + g + 10 + numberOfContours * 2 + 2 + ins;
+
+      n = 1+ttUSHORT(endPtsOfContours + numberOfContours*2-2);
+
+      m = n + 2*numberOfContours;  // a loose bound on how many vertices we might need
+      vertices = (stbtt_vertex *) STBTT_malloc(m * sizeof(vertices[0]), info->userdata);
+      if (vertices == 0)
+         return 0;
+
+      next_move = 0;
+      flagcount=0;
+
+      // in first pass, we load uninterpreted data into the allocated array
+      // above, shifted to the end of the array so we won't overwrite it when
+      // we create our final data starting from the front
+
+      off = m - n; // starting offset for uninterpreted data, regardless of how m ends up being calculated
+
+      // first load flags
+
+      for (i=0; i < n; ++i) {
+         if (flagcount == 0) {
+            flags = *points++;
+            if (flags & 8)
+               flagcount = *points++;
+         } else
+            --flagcount;
+         vertices[off+i].type = flags;
+      }
+
+      // now load x coordinates
+      x=0;
+      for (i=0; i < n; ++i) {
+         flags = vertices[off+i].type;
+         if (flags & 2) {
+            stbtt_int16 dx = *points++;
+            x += (flags & 16) ? dx : -dx; // ???
+         } else {
+            if (!(flags & 16)) {
+               x = x + (stbtt_int16) (points[0]*256 + points[1]);
+               points += 2;
+            }
+         }
+         vertices[off+i].x = (stbtt_int16) x;
+      }
+
+      // now load y coordinates
+      y=0;
+      for (i=0; i < n; ++i) {
+         flags = vertices[off+i].type;
+         if (flags & 4) {
+            stbtt_int16 dy = *points++;
+            y += (flags & 32) ? dy : -dy; // ???
+         } else {
+            if (!(flags & 32)) {
+               y = y + (stbtt_int16) (points[0]*256 + points[1]);
+               points += 2;
+            }
+         }
+         vertices[off+i].y = (stbtt_int16) y;
+      }
+
+      // now convert them to our format
+      num_vertices=0;
+      sx = sy = cx = cy = scx = scy = 0;
+      for (i=0; i < n; ++i) {
+         flags = vertices[off+i].type;
+         x     = (stbtt_int16) vertices[off+i].x;
+         y     = (stbtt_int16) vertices[off+i].y;
+
+         if (next_move == i) {
+            if (i != 0)
+               num_vertices = stbtt__close_shape(vertices, num_vertices, was_off, start_off, sx,sy,scx,scy,cx,cy);
+
+            // now start the new one               
+            start_off = !(flags & 1);
+            if (start_off) {
+               // if we start off with an off-curve point, then when we need to find a point on the curve
+               // where we can start, and we need to save some state for when we wraparound.
+               scx = x;
+               scy = y;
+               if (!(vertices[off+i+1].type & 1)) {
+                  // next point is also a curve point, so interpolate an on-point curve
+                  sx = (x + (stbtt_int32) vertices[off+i+1].x) >> 1;
+                  sy = (y + (stbtt_int32) vertices[off+i+1].y) >> 1;
+               } else {
+                  // otherwise just use the next point as our start point
+                  sx = (stbtt_int32) vertices[off+i+1].x;
+                  sy = (stbtt_int32) vertices[off+i+1].y;
+                  ++i; // we're using point i+1 as the starting point, so skip it
+               }
+            } else {
+               sx = x;
+               sy = y;
+            }
+            stbtt_setvertex(&vertices[num_vertices++], STBTT_vmove,sx,sy,0,0);
+            was_off = 0;
+            next_move = 1 + ttUSHORT(endPtsOfContours+j*2);
+            ++j;
+         } else {
+            if (!(flags & 1)) { // if it's a curve
+               if (was_off) // two off-curve control points in a row means interpolate an on-curve midpoint
+                  stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, (cx+x)>>1, (cy+y)>>1, cx, cy);
+               cx = x;
+               cy = y;
+               was_off = 1;
+            } else {
+               if (was_off)
+                  stbtt_setvertex(&vertices[num_vertices++], STBTT_vcurve, x,y, cx, cy);
+               else
+                  stbtt_setvertex(&vertices[num_vertices++], STBTT_vline, x,y,0,0);
+               was_off = 0;
+            }
+         }
+      }
+      num_vertices = stbtt__close_shape(vertices, num_vertices, was_off, start_off, sx,sy,scx,scy,cx,cy);
+   } else if (numberOfContours == -1) {
+      // Compound shapes.
+      int more = 1;
+      stbtt_uint8 *comp = data + g + 10;
+      num_vertices = 0;
+      vertices = 0;
+      while (more) {
+         stbtt_uint16 flags, gidx;
+         int comp_num_verts = 0, i;
+         stbtt_vertex *comp_verts = 0, *tmp = 0;
+         float mtx[6] = {1,0,0,1,0,0}, m, n;
+         
+         flags = ttSHORT(comp); comp+=2;
+         gidx = ttSHORT(comp); comp+=2;
+
+         if (flags & 2) { // XY values
+            if (flags & 1) { // shorts
+               mtx[4] = ttSHORT(comp); comp+=2;
+               mtx[5] = ttSHORT(comp); comp+=2;
+            } else {
+               mtx[4] = ttCHAR(comp); comp+=1;
+               mtx[5] = ttCHAR(comp); comp+=1;
+            }
+         }
+         else {
+            // @TODO handle matching point
+            STBTT_assert(0);
+         }
+         if (flags & (1<<3)) { // WE_HAVE_A_SCALE
+            mtx[0] = mtx[3] = ttSHORT(comp)/16384.0f; comp+=2;
+            mtx[1] = mtx[2] = 0;
+         } else if (flags & (1<<6)) { // WE_HAVE_AN_X_AND_YSCALE
+            mtx[0] = ttSHORT(comp)/16384.0f; comp+=2;
+            mtx[1] = mtx[2] = 0;
+            mtx[3] = ttSHORT(comp)/16384.0f; comp+=2;
+         } else if (flags & (1<<7)) { // WE_HAVE_A_TWO_BY_TWO
+            mtx[0] = ttSHORT(comp)/16384.0f; comp+=2;
+            mtx[1] = ttSHORT(comp)/16384.0f; comp+=2;
+            mtx[2] = ttSHORT(comp)/16384.0f; comp+=2;
+            mtx[3] = ttSHORT(comp)/16384.0f; comp+=2;
+         }
+         
+         // Find transformation scales.
+         m = (float) STBTT_sqrt(mtx[0]*mtx[0] + mtx[1]*mtx[1]);
+         n = (float) STBTT_sqrt(mtx[2]*mtx[2] + mtx[3]*mtx[3]);
+
+         // Get indexed glyph.
+         comp_num_verts = stbtt_GetGlyphShape(info, gidx, &comp_verts);
+         if (comp_num_verts > 0) {
+            // Transform vertices.
+            for (i = 0; i < comp_num_verts; ++i) {
+               stbtt_vertex* v = &comp_verts[i];
+               stbtt_vertex_type x,y;
+               x=v->x; y=v->y;
+               v->x = (stbtt_vertex_type)(m * (mtx[0]*x + mtx[2]*y + mtx[4]));
+               v->y = (stbtt_vertex_type)(n * (mtx[1]*x + mtx[3]*y + mtx[5]));
+               x=v->cx; y=v->cy;
+               v->cx = (stbtt_vertex_type)(m * (mtx[0]*x + mtx[2]*y + mtx[4]));
+               v->cy = (stbtt_vertex_type)(n * (mtx[1]*x + mtx[3]*y + mtx[5]));
+            }
+            // Append vertices.
+            tmp = (stbtt_vertex*)STBTT_malloc((num_vertices+comp_num_verts)*sizeof(stbtt_vertex), info->userdata);
+            if (!tmp) {
+               if (vertices) STBTT_free(vertices, info->userdata);
+               if (comp_verts) STBTT_free(comp_verts, info->userdata);
+               return 0;
+            }
+            if (num_vertices > 0) STBTT_memcpy(tmp, vertices, num_vertices*sizeof(stbtt_vertex)); //-V595
+            STBTT_memcpy(tmp+num_vertices, comp_verts, comp_num_verts*sizeof(stbtt_vertex));
+            if (vertices) STBTT_free(vertices, info->userdata);
+            vertices = tmp;
+            STBTT_free(comp_verts, info->userdata);
+            num_vertices += comp_num_verts;
+         }
+         // More components ?
+         more = flags & (1<<5);
+      }
+   } else if (numberOfContours < 0) {
+      // @TODO other compound variations?
+      STBTT_assert(0);
+   } else {
+      // numberOfCounters == 0, do nothing
+   }
+
+   *pvertices = vertices;
+   return num_vertices;
+}
+
+typedef struct
+{
+   int bounds;
+   int started;
+   float first_x, first_y;
+   float x, y;
+   stbtt_int32 min_x, max_x, min_y, max_y;
+
+   stbtt_vertex *pvertices;
+   int num_vertices;
+} stbtt__csctx;
+
+#define STBTT__CSCTX_INIT(bounds) {bounds,0, 0,0, 0,0, 0,0,0,0, NULL, 0}
+
+static void stbtt__track_vertex(stbtt__csctx *c, stbtt_int32 x, stbtt_int32 y)
+{
+   if (x > c->max_x || !c->started) c->max_x = x;
+   if (y > c->max_y || !c->started) c->max_y = y;
+   if (x < c->min_x || !c->started) c->min_x = x;
+   if (y < c->min_y || !c->started) c->min_y = y;
+   c->started = 1;
+}
+
+static void stbtt__csctx_v(stbtt__csctx *c, stbtt_uint8 type, stbtt_int32 x, stbtt_int32 y, stbtt_int32 cx, stbtt_int32 cy, stbtt_int32 cx1, stbtt_int32 cy1)
+{
+   if (c->bounds) {
+      stbtt__track_vertex(c, x, y);
+      if (type == STBTT_vcubic) {
+         stbtt__track_vertex(c, cx, cy);
+         stbtt__track_vertex(c, cx1, cy1);
+      }
+   } else {
+      stbtt_setvertex(&c->pvertices[c->num_vertices], type, x, y, cx, cy);
+      c->pvertices[c->num_vertices].cx1 = (stbtt_int16) cx1;
+      c->pvertices[c->num_vertices].cy1 = (stbtt_int16) cy1;
+   }
+   c->num_vertices++;
+}
+
+static void stbtt__csctx_close_shape(stbtt__csctx *ctx)
+{
+   if (ctx->first_x != ctx->x || ctx->first_y != ctx->y)
+      stbtt__csctx_v(ctx, STBTT_vline, (int)ctx->first_x, (int)ctx->first_y, 0, 0, 0, 0);
+}
+
+static void stbtt__csctx_rmove_to(stbtt__csctx *ctx, float dx, float dy)
+{
+   stbtt__csctx_close_shape(ctx);
+   ctx->first_x = ctx->x = ctx->x + dx;
+   ctx->first_y = ctx->y = ctx->y + dy;
+   stbtt__csctx_v(ctx, STBTT_vmove, (int)ctx->x, (int)ctx->y, 0, 0, 0, 0);
+}
+
+static void stbtt__csctx_rline_to(stbtt__csctx *ctx, float dx, float dy)
+{
+   ctx->x += dx;
+   ctx->y += dy;
+   stbtt__csctx_v(ctx, STBTT_vline, (int)ctx->x, (int)ctx->y, 0, 0, 0, 0);
+}
+
+static void stbtt__csctx_rccurve_to(stbtt__csctx *ctx, float dx1, float dy1, float dx2, float dy2, float dx3, float dy3)
+{
+   float cx1 = ctx->x + dx1;
+   float cy1 = ctx->y + dy1;
+   float cx2 = cx1 + dx2;
+   float cy2 = cy1 + dy2;
+   ctx->x = cx2 + dx3;
+   ctx->y = cy2 + dy3;
+   stbtt__csctx_v(ctx, STBTT_vcubic, (int)ctx->x, (int)ctx->y, (int)cx1, (int)cy1, (int)cx2, (int)cy2);
+}
+
+static stbtt__buf stbtt__get_subr(stbtt__buf idx, int n)
+{
+   int count = stbtt__cff_index_count(&idx);
+   int bias = 107;
+   if (count >= 33900)
+      bias = 32768;
+   else if (count >= 1240)
+      bias = 1131;
+   n += bias;
+   if (n < 0 || n >= count)
+      return stbtt__new_buf(NULL, 0);
+   return stbtt__cff_index_get(idx, n);
+}
+
+static stbtt__buf stbtt__cid_get_glyph_subrs(const stbtt_fontinfo *info, int glyph_index)
+{
+   stbtt__buf fdselect = info->fdselect;
+   int nranges, start, end, v, fmt, fdselector = -1, i;
+
+   stbtt__buf_seek(&fdselect, 0);
+   fmt = stbtt__buf_get8(&fdselect);
+   if (fmt == 0) {
+      // untested
+      stbtt__buf_skip(&fdselect, glyph_index);
+      fdselector = stbtt__buf_get8(&fdselect);
+   } else if (fmt == 3) {
+      nranges = stbtt__buf_get16(&fdselect);
+      start = stbtt__buf_get16(&fdselect);
+      for (i = 0; i < nranges; i++) {
+         v = stbtt__buf_get8(&fdselect);
+         end = stbtt__buf_get16(&fdselect);
+         if (glyph_index >= start && glyph_index < end) {
+            fdselector = v;
+            break;
+         }
+         start = end;
+      }
+   }
+   if (fdselector == -1) stbtt__new_buf(NULL, 0);
+   return stbtt__get_subrs(info->cff, stbtt__cff_index_get(info->fontdicts, fdselector));
+}
+
+static int stbtt__run_charstring(const stbtt_fontinfo *info, int glyph_index, stbtt__csctx *c)
+{
+   int in_header = 1, maskbits = 0, subr_stack_height = 0, sp = 0, v, i, b0;
+   int has_subrs = 0, clear_stack;
+   float s[48];
+   stbtt__buf subr_stack[10], subrs = info->subrs, b;
+   float f;
+
+#define STBTT__CSERR(s) (0)
+
+   // this currently ignores the initial width value, which isn't needed if we have hmtx
+   b = stbtt__cff_index_get(info->charstrings, glyph_index);
+   while (b.cursor < b.size) {
+      i = 0;
+      clear_stack = 1;
+      b0 = stbtt__buf_get8(&b);
+      switch (b0) {
+      // @TODO implement hinting
+      case 0x13: // hintmask
+      case 0x14: // cntrmask
+         if (in_header)
+            maskbits += (sp / 2); // implicit "vstem"
+         in_header = 0;
+         stbtt__buf_skip(&b, (maskbits + 7) / 8);
+         break;
+
+      case 0x01: // hstem
+      case 0x03: // vstem
+      case 0x12: // hstemhm
+      case 0x17: // vstemhm
+         maskbits += (sp / 2);
+         break;
+
+      case 0x15: // rmoveto
+         in_header = 0;
+         if (sp < 2) return STBTT__CSERR("rmoveto stack");
+         stbtt__csctx_rmove_to(c, s[sp-2], s[sp-1]);
+         break;
+      case 0x04: // vmoveto
+         in_header = 0;
+         if (sp < 1) return STBTT__CSERR("vmoveto stack");
+         stbtt__csctx_rmove_to(c, 0, s[sp-1]);
+         break;
+      case 0x16: // hmoveto
+         in_header = 0;
+         if (sp < 1) return STBTT__CSERR("hmoveto stack");
+         stbtt__csctx_rmove_to(c, s[sp-1], 0);
+         break;
+
+      case 0x05: // rlineto
+         if (sp < 2) return STBTT__CSERR("rlineto stack");
+         for (; i + 1 < sp; i += 2)
+            stbtt__csctx_rline_to(c, s[i], s[i+1]);
+         break;
+
+      // hlineto/vlineto and vhcurveto/hvcurveto alternate horizontal and vertical
+      // starting from a different place.
+
+      case 0x07: // vlineto
+         if (sp < 1) return STBTT__CSERR("vlineto stack");
+         goto vlineto;
+      case 0x06: // hlineto
+         if (sp < 1) return STBTT__CSERR("hlineto stack");
+         for (;;) {
+            if (i >= sp) break;
+            stbtt__csctx_rline_to(c, s[i], 0);
+            i++;
+      vlineto:
+            if (i >= sp) break;
+            stbtt__csctx_rline_to(c, 0, s[i]);
+            i++;
+         }
+         break;
+
+      case 0x1F: // hvcurveto
+         if (sp < 4) return STBTT__CSERR("hvcurveto stack");
+         goto hvcurveto;
+      case 0x1E: // vhcurveto
+         if (sp < 4) return STBTT__CSERR("vhcurveto stack");
+         for (;;) {
+            if (i + 3 >= sp) break;
+            stbtt__csctx_rccurve_to(c, 0, s[i], s[i+1], s[i+2], s[i+3], (sp - i == 5) ? s[i + 4] : 0.0f);
+            i += 4;
+      hvcurveto:
+            if (i + 3 >= sp) break;
+            stbtt__csctx_rccurve_to(c, s[i], 0, s[i+1], s[i+2], (sp - i == 5) ? s[i+4] : 0.0f, s[i+3]);
+            i += 4;
+         }
+         break;
+
+      case 0x08: // rrcurveto
+         if (sp < 6) return STBTT__CSERR("rcurveline stack");
+         for (; i + 5 < sp; i += 6)
+            stbtt__csctx_rccurve_to(c, s[i], s[i+1], s[i+2], s[i+3], s[i+4], s[i+5]);
+         break;
+
+      case 0x18: // rcurveline
+         if (sp < 8) return STBTT__CSERR("rcurveline stack");
+         for (; i + 5 < sp - 2; i += 6)
+            stbtt__csctx_rccurve_to(c, s[i], s[i+1], s[i+2], s[i+3], s[i+4], s[i+5]);
+         if (i + 1 >= sp) return STBTT__CSERR("rcurveline stack");
+         stbtt__csctx_rline_to(c, s[i], s[i+1]);
+         break;
+
+      case 0x19: // rlinecurve
+         if (sp < 8) return STBTT__CSERR("rlinecurve stack");
+         for (; i + 1 < sp - 6; i += 2)
+            stbtt__csctx_rline_to(c, s[i], s[i+1]);
+         if (i + 5 >= sp) return STBTT__CSERR("rlinecurve stack");
+         stbtt__csctx_rccurve_to(c, s[i], s[i+1], s[i+2], s[i+3], s[i+4], s[i+5]);
+         break;
+
+      case 0x1A: // vvcurveto
+      case 0x1B: // hhcurveto
+         if (sp < 4) return STBTT__CSERR("(vv|hh)curveto stack");
+         f = 0.0;
+         if (sp & 1) { f = s[i]; i++; }
+         for (; i + 3 < sp; i += 4) {
+            if (b0 == 0x1B)
+               stbtt__csctx_rccurve_to(c, s[i], f, s[i+1], s[i+2], s[i+3], 0.0);
+            else
+               stbtt__csctx_rccurve_to(c, f, s[i], s[i+1], s[i+2], 0.0, s[i+3]);
+            f = 0.0;
+         }
+         break;
+
+      case 0x0A: // callsubr
+         if (!has_subrs) {
+            if (info->fdselect.size)
+               subrs = stbtt__cid_get_glyph_subrs(info, glyph_index);
+            has_subrs = 1;
+         }
+         // fallthrough
+      case 0x1D: // callgsubr
+         if (sp < 1) return STBTT__CSERR("call(g|)subr stack");
+         v = (int) s[--sp];
+         if (subr_stack_height >= 10) return STBTT__CSERR("recursion limit");
+         subr_stack[subr_stack_height++] = b;
+         b = stbtt__get_subr(b0 == 0x0A ? subrs : info->gsubrs, v);
+         if (b.size == 0) return STBTT__CSERR("subr not found");
+         b.cursor = 0;
+         clear_stack = 0;
+         break;
+
+      case 0x0B: // return
+         if (subr_stack_height <= 0) return STBTT__CSERR("return outside subr");
+         b = subr_stack[--subr_stack_height];
+         clear_stack = 0;
+         break;
+
+      case 0x0E: // endchar
+         stbtt__csctx_close_shape(c);
+         return 1;
+
+      case 0x0C: { // two-byte escape
+         float dx1, dx2, dx3, dx4, dx5, dx6, dy1, dy2, dy3, dy4, dy5, dy6;
+         float dx, dy;
+         int b1 = stbtt__buf_get8(&b);
+         switch (b1) {
+         // @TODO These "flex" implementations ignore the flex-depth and resolution,
+         // and always draw beziers.
+         case 0x22: // hflex
+            if (sp < 7) return STBTT__CSERR("hflex stack");
+            dx1 = s[0];
+            dx2 = s[1];
+            dy2 = s[2];
+            dx3 = s[3];
+            dx4 = s[4];
+            dx5 = s[5];
+            dx6 = s[6];
+            stbtt__csctx_rccurve_to(c, dx1, 0, dx2, dy2, dx3, 0);
+            stbtt__csctx_rccurve_to(c, dx4, 0, dx5, -dy2, dx6, 0);
+            break;
+
+         case 0x23: // flex
+            if (sp < 13) return STBTT__CSERR("flex stack");
+            dx1 = s[0];
+            dy1 = s[1];
+            dx2 = s[2];
+            dy2 = s[3];
+            dx3 = s[4];
+            dy3 = s[5];
+            dx4 = s[6];
+            dy4 = s[7];
+            dx5 = s[8];
+            dy5 = s[9];
+            dx6 = s[10];
+            dy6 = s[11];
+            //fd is s[12]
+            stbtt__csctx_rccurve_to(c, dx1, dy1, dx2, dy2, dx3, dy3);
+            stbtt__csctx_rccurve_to(c, dx4, dy4, dx5, dy5, dx6, dy6);
+            break;
+
+         case 0x24: // hflex1
+            if (sp < 9) return STBTT__CSERR("hflex1 stack");
+            dx1 = s[0];
+            dy1 = s[1];
+            dx2 = s[2];
+            dy2 = s[3];
+            dx3 = s[4];
+            dx4 = s[5];
+            dx5 = s[6];
+            dy5 = s[7];
+            dx6 = s[8];
+            stbtt__csctx_rccurve_to(c, dx1, dy1, dx2, dy2, dx3, 0);
+            stbtt__csctx_rccurve_to(c, dx4, 0, dx5, dy5, dx6, -(dy1+dy2+dy5));
+            break;
+
+         case 0x25: // flex1
+            if (sp < 11) return STBTT__CSERR("flex1 stack");
+            dx1 = s[0];
+            dy1 = s[1];
+            dx2 = s[2];
+            dy2 = s[3];
+            dx3 = s[4];
+            dy3 = s[5];
+            dx4 = s[6];
+            dy4 = s[7];
+            dx5 = s[8];
+            dy5 = s[9];
+            dx6 = dy6 = s[10];
+            dx = dx1+dx2+dx3+dx4+dx5;
+            dy = dy1+dy2+dy3+dy4+dy5;
+            if (STBTT_fabs(dx) > STBTT_fabs(dy))
+               dy6 = -dy;
+            else
+               dx6 = -dx;
+            stbtt__csctx_rccurve_to(c, dx1, dy1, dx2, dy2, dx3, dy3);
+            stbtt__csctx_rccurve_to(c, dx4, dy4, dx5, dy5, dx6, dy6);
+            break;
+
+         default:
+            return STBTT__CSERR("unimplemented");
+         }
+      } break;
+
+      default:
+         if (b0 != 255 && b0 != 28 && (b0 < 32 || b0 > 254)) //-V560
+            return STBTT__CSERR("reserved operator");
+
+         // push immediate
+         if (b0 == 255) {
+            f = (float)(stbtt_int32)stbtt__buf_get32(&b) / 0x10000;
+         } else {
+            stbtt__buf_skip(&b, -1);
+            f = (float)(stbtt_int16)stbtt__cff_int(&b);
+         }
+         if (sp >= 48) return STBTT__CSERR("push stack overflow");
+         s[sp++] = f;
+         clear_stack = 0;
+         break;
+      }
+      if (clear_stack) sp = 0;
+   }
+   return STBTT__CSERR("no endchar");
+
+#undef STBTT__CSERR
+}
+
+static int stbtt__GetGlyphShapeT2(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **pvertices)
+{
+   // runs the charstring twice, once to count and once to output (to avoid realloc)
+   stbtt__csctx count_ctx = STBTT__CSCTX_INIT(1);
+   stbtt__csctx output_ctx = STBTT__CSCTX_INIT(0);
+   if (stbtt__run_charstring(info, glyph_index, &count_ctx)) {
+      *pvertices = (stbtt_vertex*)STBTT_malloc(count_ctx.num_vertices*sizeof(stbtt_vertex), info->userdata);
+      output_ctx.pvertices = *pvertices;
+      if (stbtt__run_charstring(info, glyph_index, &output_ctx)) {
+         STBTT_assert(output_ctx.num_vertices == count_ctx.num_vertices);
+         return output_ctx.num_vertices;
+      }
+   }
+   *pvertices = NULL;
+   return 0;
+}
+
+static int stbtt__GetGlyphInfoT2(const stbtt_fontinfo *info, int glyph_index, int *x0, int *y0, int *x1, int *y1)
+{
+   stbtt__csctx c = STBTT__CSCTX_INIT(1);
+   int r = stbtt__run_charstring(info, glyph_index, &c);
+   if (x0)  *x0 = r ? c.min_x : 0;
+   if (y0)  *y0 = r ? c.min_y : 0;
+   if (x1)  *x1 = r ? c.max_x : 0;
+   if (y1)  *y1 = r ? c.max_y : 0;
+   return r ? c.num_vertices : 0;
+}
+
+STBTT_DEF int stbtt_GetGlyphShape(const stbtt_fontinfo *info, int glyph_index, stbtt_vertex **pvertices)
+{
+   if (!info->cff.size)
+      return stbtt__GetGlyphShapeTT(info, glyph_index, pvertices);
+   else
+      return stbtt__GetGlyphShapeT2(info, glyph_index, pvertices);
+}
+
+STBTT_DEF void stbtt_GetGlyphHMetrics(const stbtt_fontinfo *info, int glyph_index, int *advanceWidth, int *leftSideBearing)
+{
+   stbtt_uint16 numOfLongHorMetrics = ttUSHORT(info->data+info->hhea + 34);
+   if (glyph_index < numOfLongHorMetrics) {
+      if (advanceWidth)     *advanceWidth    = ttSHORT(info->data + info->hmtx + 4*glyph_index);
+      if (leftSideBearing)  *leftSideBearing = ttSHORT(info->data + info->hmtx + 4*glyph_index + 2);
+   } else {
+      if (advanceWidth)     *advanceWidth    = ttSHORT(info->data + info->hmtx + 4*(numOfLongHorMetrics-1));
+      if (leftSideBearing)  *leftSideBearing = ttSHORT(info->data + info->hmtx + 4*numOfLongHorMetrics + 2*(glyph_index - numOfLongHorMetrics));
+   }
+}
+
+static int  stbtt__GetGlyphKernInfoAdvance(const stbtt_fontinfo *info, int glyph1, int glyph2)
+{
+   stbtt_uint8 *data = info->data + info->kern;
+   stbtt_uint32 needle, straw;
+   int l, r, m;
+
+   // we only look at the first table. it must be 'horizontal' and format 0.
+   if (!info->kern)
+      return 0;
+   if (ttUSHORT(data+2) < 1) // number of tables, need at least 1
+      return 0;
+   if (ttUSHORT(data+8) != 1) // horizontal flag must be set in format
+      return 0;
+
+   l = 0;
+   r = ttUSHORT(data+10) - 1;
+   needle = glyph1 << 16 | glyph2;
+   while (l <= r) {
+      m = (l + r) >> 1;
+      straw = ttULONG(data+18+(m*6)); // note: unaligned read
+      if (needle < straw)
+         r = m - 1;
+      else if (needle > straw)
+         l = m + 1;
+      else
+         return ttSHORT(data+22+(m*6));
+   }
+   return 0;
+}
+
+static stbtt_int32  stbtt__GetCoverageIndex(stbtt_uint8 *coverageTable, int glyph)
+{
+    stbtt_uint16 coverageFormat = ttUSHORT(coverageTable);
+    switch(coverageFormat) {
+        case 1: {
+            stbtt_uint16 glyphCount = ttUSHORT(coverageTable + 2);
+
+            // Binary search.
+            stbtt_int32 l=0, r=glyphCount-1, m;
+            int straw, needle=glyph;
+            while (l <= r) {
+                stbtt_uint8 *glyphArray = coverageTable + 4;
+                stbtt_uint16 glyphID;
+                m = (l + r) >> 1;
+                glyphID = ttUSHORT(glyphArray + 2 * m);
+                straw = glyphID;
+                if (needle < straw)
+                    r = m - 1;
+                else if (needle > straw)
+                    l = m + 1;
+                else {
+                     return m;
+                }
+            }
+        } break;
+
+        case 2: {
+            stbtt_uint16 rangeCount = ttUSHORT(coverageTable + 2);
+            stbtt_uint8 *rangeArray = coverageTable + 4;
+
+            // Binary search.
+            stbtt_int32 l=0, r=rangeCount-1, m;
+            int strawStart, strawEnd, needle=glyph;
+            while (l <= r) {
+                stbtt_uint8 *rangeRecord;
+                m = (l + r) >> 1;
+                rangeRecord = rangeArray + 6 * m;
+                strawStart = ttUSHORT(rangeRecord);
+                strawEnd = ttUSHORT(rangeRecord + 2);
+                if (needle < strawStart)
+                    r = m - 1;
+                else if (needle > strawEnd)
+                    l = m + 1;
+                else {
+                    stbtt_uint16 startCoverageIndex = ttUSHORT(rangeRecord + 4);
+                    return startCoverageIndex + glyph - strawStart;
+                }
+            }
+        } break;
+
+        default: {
+            // There are no other cases.
+            STBTT_assert(0);
+        } break;
+    }
+
+    return -1;
+}
+
+static stbtt_int32  stbtt__GetGlyphClass(stbtt_uint8 *classDefTable, int glyph)
+{
+    stbtt_uint16 classDefFormat = ttUSHORT(classDefTable);
+    switch(classDefFormat)
+    {
+        case 1: {
+            stbtt_uint16 startGlyphID = ttUSHORT(classDefTable + 2);
+            stbtt_uint16 glyphCount = ttUSHORT(classDefTable + 4);
+            stbtt_uint8 *classDef1ValueArray = classDefTable + 6;
+
+            if (glyph >= startGlyphID && glyph < startGlyphID + glyphCount)
+                return (stbtt_int32)ttUSHORT(classDef1ValueArray + 2 * (glyph - startGlyphID));
+
+            // [DEAR IMGUI] Commented to fix static analyzer warning
+            //classDefTable = classDef1ValueArray + 2 * glyphCount;
+        } break;
+
+        case 2: {
+            stbtt_uint16 classRangeCount = ttUSHORT(classDefTable + 2);
+            stbtt_uint8 *classRangeRecords = classDefTable + 4;
+
+            // Binary search.
+            stbtt_int32 l=0, r=classRangeCount-1, m;
+            int strawStart, strawEnd, needle=glyph;
+            while (l <= r) {
+                stbtt_uint8 *classRangeRecord;
+                m = (l + r) >> 1;
+                classRangeRecord = classRangeRecords + 6 * m;
+                strawStart = ttUSHORT(classRangeRecord);
+                strawEnd = ttUSHORT(classRangeRecord + 2);
+                if (needle < strawStart)
+                    r = m - 1;
+                else if (needle > strawEnd)
+                    l = m + 1;
+                else
+                    return (stbtt_int32)ttUSHORT(classRangeRecord + 4);
+            }
+
+            // [DEAR IMGUI] Commented to fix static analyzer warning
+            //classDefTable = classRangeRecords + 6 * classRangeCount;
+        } break;
+
+        default: {
+            // There are no other cases.
+            STBTT_assert(0);
+        } break;
+    }
+
+    return -1;
+}
+
+// Define to STBTT_assert(x) if you want to break on unimplemented formats.
+#define STBTT_GPOS_TODO_assert(x)
+
+static stbtt_int32  stbtt__GetGlyphGPOSInfoAdvance(const stbtt_fontinfo *info, int glyph1, int glyph2)
+{
+    stbtt_uint16 lookupListOffset;
+    stbtt_uint8 *lookupList;
+    stbtt_uint16 lookupCount;
+    stbtt_uint8 *data;
+    stbtt_int32 i;
+
+    if (!info->gpos) return 0;
+
+    data = info->data + info->gpos;
+
+    if (ttUSHORT(data+0) != 1) return 0; // Major version 1
+    if (ttUSHORT(data+2) != 0) return 0; // Minor version 0
+
+    lookupListOffset = ttUSHORT(data+8);
+    lookupList = data + lookupListOffset;
+    lookupCount = ttUSHORT(lookupList);
+
+    for (i=0; i<lookupCount; ++i) {
+        stbtt_uint16 lookupOffset = ttUSHORT(lookupList + 2 + 2 * i);
+        stbtt_uint8 *lookupTable = lookupList + lookupOffset;
+
+        stbtt_uint16 lookupType = ttUSHORT(lookupTable);
+        stbtt_uint16 subTableCount = ttUSHORT(lookupTable + 4);
+        stbtt_uint8 *subTableOffsets = lookupTable + 6;
+        switch(lookupType) {
+            case 2: { // Pair Adjustment Positioning Subtable
+                stbtt_int32 sti;
+                for (sti=0; sti<subTableCount; sti++) {
+                    stbtt_uint16 subtableOffset = ttUSHORT(subTableOffsets + 2 * sti);
+                    stbtt_uint8 *table = lookupTable + subtableOffset;
+                    stbtt_uint16 posFormat = ttUSHORT(table);
+                    stbtt_uint16 coverageOffset = ttUSHORT(table + 2);
+                    stbtt_int32 coverageIndex = stbtt__GetCoverageIndex(table + coverageOffset, glyph1);
+                    if (coverageIndex == -1) continue;
+
+                    switch (posFormat) {
+                        case 1: {
+                            stbtt_int32 l, r, m;
+                            int straw, needle;
+                            stbtt_uint16 valueFormat1 = ttUSHORT(table + 4);
+                            stbtt_uint16 valueFormat2 = ttUSHORT(table + 6);
+                            stbtt_int32 valueRecordPairSizeInBytes = 2;
+                            stbtt_uint16 pairSetCount = ttUSHORT(table + 8);
+                            stbtt_uint16 pairPosOffset = ttUSHORT(table + 10 + 2 * coverageIndex);
+                            stbtt_uint8 *pairValueTable = table + pairPosOffset;
+                            stbtt_uint16 pairValueCount = ttUSHORT(pairValueTable);
+                            stbtt_uint8 *pairValueArray = pairValueTable + 2;
+                            // TODO: Support more formats.
+                            STBTT_GPOS_TODO_assert(valueFormat1 == 4);
+                            if (valueFormat1 != 4) return 0;
+                            STBTT_GPOS_TODO_assert(valueFormat2 == 0);
+                            if (valueFormat2 != 0) return 0;
+
+                            STBTT_assert(coverageIndex < pairSetCount);
+                            STBTT__NOTUSED(pairSetCount);
+
+                            needle=glyph2;
+                            r=pairValueCount-1;
+                            l=0;
+
+                            // Binary search.
+                            while (l <= r) {
+                                stbtt_uint16 secondGlyph;
+                                stbtt_uint8 *pairValue;
+                                m = (l + r) >> 1;
+                                pairValue = pairValueArray + (2 + valueRecordPairSizeInBytes) * m;
+                                secondGlyph = ttUSHORT(pairValue);
+                                straw = secondGlyph;
+                                if (needle < straw)
+                                    r = m - 1;
+                                else if (needle > straw)
+                                    l = m + 1;
+                                else {
+                                    stbtt_int16 xAdvance = ttSHORT(pairValue + 2);
+                                    return xAdvance;
+                                }
+                            }
+                        } break;
+
+                        case 2: {
+                            stbtt_uint16 valueFormat1 = ttUSHORT(table + 4);
+                            stbtt_uint16 valueFormat2 = ttUSHORT(table + 6);
+
+                            stbtt_uint16 classDef1Offset = ttUSHORT(table + 8);
+                            stbtt_uint16 classDef2Offset = ttUSHORT(table + 10);
+                            int glyph1class = stbtt__GetGlyphClass(table + classDef1Offset, glyph1);
+                            int glyph2class = stbtt__GetGlyphClass(table + classDef2Offset, glyph2);
+
+                            stbtt_uint16 class1Count = ttUSHORT(table + 12);
+                            stbtt_uint16 class2Count = ttUSHORT(table + 14);
+                            STBTT_assert(glyph1class < class1Count);
+                            STBTT_assert(glyph2class < class2Count);
+
+                            // TODO: Support more formats.
+                            STBTT_GPOS_TODO_assert(valueFormat1 == 4);
+                            if (valueFormat1 != 4) return 0;
+                            STBTT_GPOS_TODO_assert(valueFormat2 == 0);
+                            if (valueFormat2 != 0) return 0;
+
+                            if (glyph1class >= 0 && glyph1class < class1Count && glyph2class >= 0 && glyph2class < class2Count) {
+                                stbtt_uint8 *class1Records = table + 16;
+                                stbtt_uint8 *class2Records = class1Records + 2 * (glyph1class * class2Count);
+                                stbtt_int16 xAdvance = ttSHORT(class2Records + 2 * glyph2class);
+                                return xAdvance;
+                            }
+                        } break;
+
+                        default: {
+                            // There are no other cases.
+                            STBTT_assert(0);
+                            break;
+                        } // [DEAR IMGUI] removed ;
+                    }
+                }
+                break;
+            } // [DEAR IMGUI] removed ;
+
+            default:
+                // TODO: Implement other stuff.
+                break;
+        }
+    }
+
+    return 0;
+}
+
+STBTT_DEF int  stbtt_GetGlyphKernAdvance(const stbtt_fontinfo *info, int g1, int g2)
+{
+   int xAdvance = 0;
+
+   if (info->gpos)
+      xAdvance += stbtt__GetGlyphGPOSInfoAdvance(info, g1, g2);
+
+   if (info->kern)
+      xAdvance += stbtt__GetGlyphKernInfoAdvance(info, g1, g2);
+
+   return xAdvance;
+}
+
+STBTT_DEF int  stbtt_GetCodepointKernAdvance(const stbtt_fontinfo *info, int ch1, int ch2)
+{
+   if (!info->kern && !info->gpos) // if no kerning table, don't waste time looking up both codepoint->glyphs
+      return 0;
+   return stbtt_GetGlyphKernAdvance(info, stbtt_FindGlyphIndex(info,ch1), stbtt_FindGlyphIndex(info,ch2));
+}
+
+STBTT_DEF void stbtt_GetCodepointHMetrics(const stbtt_fontinfo *info, int codepoint, int *advanceWidth, int *leftSideBearing)
+{
+   stbtt_GetGlyphHMetrics(info, stbtt_FindGlyphIndex(info,codepoint), advanceWidth, leftSideBearing);
+}
+
+STBTT_DEF void stbtt_GetFontVMetrics(const stbtt_fontinfo *info, int *ascent, int *descent, int *lineGap)
+{
+   if (ascent ) *ascent  = ttSHORT(info->data+info->hhea + 4);
+   if (descent) *descent = ttSHORT(info->data+info->hhea + 6);
+   if (lineGap) *lineGap = ttSHORT(info->data+info->hhea + 8);
+}
+
+STBTT_DEF int  stbtt_GetFontVMetricsOS2(const stbtt_fontinfo *info, int *typoAscent, int *typoDescent, int *typoLineGap)
+{
+   int tab = stbtt__find_table(info->data, info->fontstart, "OS/2");
+   if (!tab)
+      return 0;
+   if (typoAscent ) *typoAscent  = ttSHORT(info->data+tab + 68);
+   if (typoDescent) *typoDescent = ttSHORT(info->data+tab + 70);
+   if (typoLineGap) *typoLineGap = ttSHORT(info->data+tab + 72);
+   return 1;
+}
+
+STBTT_DEF void stbtt_GetFontBoundingBox(const stbtt_fontinfo *info, int *x0, int *y0, int *x1, int *y1)
+{
+   *x0 = ttSHORT(info->data + info->head + 36);
+   *y0 = ttSHORT(info->data + info->head + 38);
+   *x1 = ttSHORT(info->data + info->head + 40);
+   *y1 = ttSHORT(info->data + info->head + 42);
+}
+
+STBTT_DEF float stbtt_ScaleForPixelHeight(const stbtt_fontinfo *info, float height)
+{
+   int fheight = ttSHORT(info->data + info->hhea + 4) - ttSHORT(info->data + info->hhea + 6);
+   return (float) height / fheight;
+}
+
+STBTT_DEF float stbtt_ScaleForMappingEmToPixels(const stbtt_fontinfo *info, float pixels)
+{
+   int unitsPerEm = ttUSHORT(info->data + info->head + 18);
+   return pixels / unitsPerEm;
+}
+
+STBTT_DEF void stbtt_FreeShape(const stbtt_fontinfo *info, stbtt_vertex *v)
+{
+   STBTT_free(v, info->userdata);
+}
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// antialiasing software rasterizer
+//
+
+STBTT_DEF void stbtt_GetGlyphBitmapBoxSubpixel(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y,float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1)
+{
+   int x0=0,y0=0,x1,y1; // =0 suppresses compiler warning
+   if (!stbtt_GetGlyphBox(font, glyph, &x0,&y0,&x1,&y1)) {
+      // e.g. space character
+      if (ix0) *ix0 = 0;
+      if (iy0) *iy0 = 0;
+      if (ix1) *ix1 = 0;
+      if (iy1) *iy1 = 0;
+   } else {
+      // move to integral bboxes (treating pixels as little squares, what pixels get touched)?
+      if (ix0) *ix0 = STBTT_ifloor( x0 * scale_x + shift_x);
+      if (iy0) *iy0 = STBTT_ifloor(-y1 * scale_y + shift_y);
+      if (ix1) *ix1 = STBTT_iceil ( x1 * scale_x + shift_x);
+      if (iy1) *iy1 = STBTT_iceil (-y0 * scale_y + shift_y);
+   }
+}
+
+STBTT_DEF void stbtt_GetGlyphBitmapBox(const stbtt_fontinfo *font, int glyph, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1)
+{
+   stbtt_GetGlyphBitmapBoxSubpixel(font, glyph, scale_x, scale_y,0.0f,0.0f, ix0, iy0, ix1, iy1);
+}
+
+STBTT_DEF void stbtt_GetCodepointBitmapBoxSubpixel(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, float shift_x, float shift_y, int *ix0, int *iy0, int *ix1, int *iy1)
+{
+   stbtt_GetGlyphBitmapBoxSubpixel(font, stbtt_FindGlyphIndex(font,codepoint), scale_x, scale_y,shift_x,shift_y, ix0,iy0,ix1,iy1);
+}
+
+STBTT_DEF void stbtt_GetCodepointBitmapBox(const stbtt_fontinfo *font, int codepoint, float scale_x, float scale_y, int *ix0, int *iy0, int *ix1, int *iy1)
+{
+   stbtt_GetCodepointBitmapBoxSubpixel(font, codepoint, scale_x, scale_y,0.0f,0.0f, ix0,iy0,ix1,iy1);
+}
+
+//////////////////////////////////////////////////////////////////////////////
+//
+//  Rasterizer
+
+typedef struct stbtt__hheap_chunk
+{
+   struct stbtt__hheap_chunk *next;
+} stbtt__hheap_chunk;
+
+typedef struct stbtt__hheap
+{
+   struct stbtt__hheap_chunk *head;
+   void   *first_free;
+   int    num_remaining_in_head_chunk;
+} stbtt__hheap;
+
+static void *stbtt__hheap_alloc(stbtt__hheap *hh, size_t size, void *userdata)
+{
+   if (hh->first_free) {
+      void *p = hh->first_free;
+      hh->first_free = * (void **) p;
+      return p;
+   } else {
+      if (hh->num_remaining_in_head_chunk == 0) {
+         int count = (size < 32 ? 2000 : size < 128 ? 800 : 100);
+         stbtt__hheap_chunk *c = (stbtt__hheap_chunk *) STBTT_malloc(sizeof(stbtt__hheap_chunk) + size * count, userdata);
+         if (c == NULL)
+            return NULL;
+         c->next = hh->head;
+         hh->head = c;
+         hh->num_remaining_in_head_chunk = count;
+      }
+      --hh->num_remaining_in_head_chunk;
+      return (char *) (hh->head) + sizeof(stbtt__hheap_chunk) + size * hh->num_remaining_in_head_chunk;
+   }
+}
+
+static void stbtt__hheap_free(stbtt__hheap *hh, void *p)
+{
+   *(void **) p = hh->first_free;
+   hh->first_free = p;
+}
+
+static void stbtt__hheap_cleanup(stbtt__hheap *hh, void *userdata)
+{
+   stbtt__hheap_chunk *c = hh->head;
+   while (c) {
+      stbtt__hheap_chunk *n = c->next;
+      STBTT_free(c, userdata);
+      c = n;
+   }
+}
+
+typedef struct stbtt__edge {
+   float x0,y0, x1,y1;
+   int invert;
+} stbtt__edge;
+
+
+typedef struct stbtt__active_edge
+{
+   struct stbtt__active_edge *next;
+   #if STBTT_RASTERIZER_VERSION==1
+   int x,dx;
+   float ey;
+   int direction;
+   #elif STBTT_RASTERIZER_VERSION==2
+   float fx,fdx,fdy;
+   float direction;
+   float sy;
+   float ey;
+   #else
+   #error "Unrecognized value of STBTT_RASTERIZER_VERSION"
+   #endif
+} stbtt__active_edge;
+
+#if STBTT_RASTERIZER_VERSION == 1
+#define STBTT_FIXSHIFT   10
+#define STBTT_FIX        (1 << STBTT_FIXSHIFT)
+#define STBTT_FIXMASK    (STBTT_FIX-1)
+
+static stbtt__active_edge *stbtt__new_active(stbtt__hheap *hh, stbtt__edge *e, int off_x, float start_point, void *userdata)
+{
+   stbtt__active_edge *z = (stbtt__active_edge *) stbtt__hheap_alloc(hh, sizeof(*z), userdata);
+   float dxdy = (e->x1 - e->x0) / (e->y1 - e->y0);
+   STBTT_assert(z != NULL);
+   if (!z) return z;
+   
+   // round dx down to avoid overshooting
+   if (dxdy < 0)
+      z->dx = -STBTT_ifloor(STBTT_FIX * -dxdy);
+   else
+      z->dx = STBTT_ifloor(STBTT_FIX * dxdy);
+
+   z->x = STBTT_ifloor(STBTT_FIX * e->x0 + z->dx * (start_point - e->y0)); // use z->dx so when we offset later it's by the same amount
+   z->x -= off_x * STBTT_FIX;
+
+   z->ey = e->y1;
+   z->next = 0;
+   z->direction = e->invert ? 1 : -1;
+   return z;
+}
+#elif STBTT_RASTERIZER_VERSION == 2
+static stbtt__active_edge *stbtt__new_active(stbtt__hheap *hh, stbtt__edge *e, int off_x, float start_point, void *userdata)
+{
+   stbtt__active_edge *z = (stbtt__active_edge *) stbtt__hheap_alloc(hh, sizeof(*z), userdata);
+   float dxdy = (e->x1 - e->x0) / (e->y1 - e->y0);
+   STBTT_assert(z != NULL);
+   //STBTT_assert(e->y0 <= start_point);
+   if (!z) return z;
+   z->fdx = dxdy;
+   z->fdy = dxdy != 0.0f ? (1.0f/dxdy) : 0.0f;
+   z->fx = e->x0 + dxdy * (start_point - e->y0);
+   z->fx -= off_x;
+   z->direction = e->invert ? 1.0f : -1.0f;
+   z->sy = e->y0;
+   z->ey = e->y1;
+   z->next = 0;
+   return z;
+}
+#else
+#error "Unrecognized value of STBTT_RASTERIZER_VERSION"
+#endif
+
+#if STBTT_RASTERIZER_VERSION == 1
+// note: this routine clips fills that extend off the edges... ideally this
+// wouldn't happen, but it could happen if the truetype glyph bounding boxes
+// are wrong, or if the user supplies a too-small bitmap
+static void stbtt__fill_active_edges(unsigned char *scanline, int len, stbtt__active_edge *e, int max_weight)
+{
+   // non-zero winding fill
+   int x0=0, w=0;
+
+   while (e) {
+      if (w == 0) {
+         // if we're currently at zero, we need to record the edge start point
+         x0 = e->x; w += e->direction;
+      } else {
+         int x1 = e->x; w += e->direction;
+         // if we went to zero, we need to draw
+         if (w == 0) {
+            int i = x0 >> STBTT_FIXSHIFT;
+            int j = x1 >> STBTT_FIXSHIFT;
+
+            if (i < len && j >= 0) {
+               if (i == j) {
+                  // x0,x1 are the same pixel, so compute combined coverage
+                  scanline[i] = scanline[i] + (stbtt_uint8) ((x1 - x0) * max_weight >> STBTT_FIXSHIFT);
+               } else {
+                  if (i >= 0) // add antialiasing for x0
+                     scanline[i] = scanline[i] + (stbtt_uint8) (((STBTT_FIX - (x0 & STBTT_FIXMASK)) * max_weight) >> STBTT_FIXSHIFT);
+                  else
+                     i = -1; // clip
+
+                  if (j < len) // add antialiasing for x1
+                     scanline[j] = scanline[j] + (stbtt_uint8) (((x1 & STBTT_FIXMASK) * max_weight) >> STBTT_FIXSHIFT);
+                  else
+                     j = len; // clip
+
+                  for (++i; i < j; ++i) // fill pixels between x0 and x1
+                     scanline[i] = scanline[i] + (stbtt_uint8) max_weight;
+               }
+            }
+         }
+      }
+      
+      e = e->next;
+   }
+}
+
+static void stbtt__rasterize_sorted_edges(stbtt__bitmap *result, stbtt__edge *e, int n, int vsubsample, int off_x, int off_y, void *userdata)
+{
+   stbtt__hheap hh = { 0, 0, 0 };
+   stbtt__active_edge *active = NULL;
+   int y,j=0;
+   int max_weight = (255 / vsubsample);  // weight per vertical scanline
+   int s; // vertical subsample index
+   unsigned char scanline_data[512], *scanline;
+
+   if (result->w > 512)
+      scanline = (unsigned char *) STBTT_malloc(result->w, userdata);
+   else
+      scanline = scanline_data;
+
+   y = off_y * vsubsample;
+   e[n].y0 = (off_y + result->h) * (float) vsubsample + 1;
+
+   while (j < result->h) {
+      STBTT_memset(scanline, 0, result->w);
+      for (s=0; s < vsubsample; ++s) {
+         // find center of pixel for this scanline
+         float scan_y = y + 0.5f;
+         stbtt__active_edge **step = &active;
+
+         // update all active edges;
+         // remove all active edges that terminate before the center of this scanline
+         while (*step) {
+            stbtt__active_edge * z = *step;
+            if (z->ey <= scan_y) {
+               *step = z->next; // delete from list
+               STBTT_assert(z->direction);
+               z->direction = 0;
+               stbtt__hheap_free(&hh, z);
+            } else {
+               z->x += z->dx; // advance to position for current scanline
+               step = &((*step)->next); // advance through list
+            }
+         }
+
+         // resort the list if needed
+         for(;;) {
+            int changed=0;
+            step = &active;
+            while (*step && (*step)->next) {
+               if ((*step)->x > (*step)->next->x) {
+                  stbtt__active_edge *t = *step;
+                  stbtt__active_edge *q = t->next;
+
+                  t->next = q->next;
+                  q->next = t;
+                  *step = q;
+                  changed = 1;
+               }
+               step = &(*step)->next;
+            }
+            if (!changed) break;
+         }
+
+         // insert all edges that start before the center of this scanline -- omit ones that also end on this scanline
+         while (e->y0 <= scan_y) {
+            if (e->y1 > scan_y) {
+               stbtt__active_edge *z = stbtt__new_active(&hh, e, off_x, scan_y, userdata);
+               if (z != NULL) {
+                  // find insertion point
+                  if (active == NULL)
+                     active = z;
+                  else if (z->x < active->x) {
+                     // insert at front
+                     z->next = active;
+                     active = z;
+                  } else {
+                     // find thing to insert AFTER
+                     stbtt__active_edge *p = active;
+                     while (p->next && p->next->x < z->x)
+                        p = p->next;
+                     // at this point, p->next->x is NOT < z->x
+                     z->next = p->next;
+                     p->next = z;
+                  }
+               }
+            }
+            ++e;
+         }
+
+         // now process all active edges in XOR fashion
+         if (active)
+            stbtt__fill_active_edges(scanline, result->w, active, max_weight);
+
+         ++y;
+      }
+      STBTT_memcpy(result->pixels + j * result->stride, scanline, result->w);
+      ++j;
+   }
+
+   stbtt__hheap_cleanup(&hh, userdata);
+
+   if (scanline != scanline_data)
+      STBTT_free(scanline, userdata);
+}
+
+#elif STBTT_RASTERIZER_VERSION == 2
+
+// the edge passed in here does not cross the vertical line at x or the vertical line at x+1
+// (i.e. it has already been clipped to those)
+static void stbtt__handle_clipped_edge(float *scanline, int x, stbtt__active_edge *e, float x0, float y0, float x1, float y1)
+{
+   if (y0 == y1) return;
+   STBTT_assert(y0 < y1);
+   STBTT_assert(e->sy <= e->ey);
+   if (y0 > e->ey) return;
+   if (y1 < e->sy) return;
+   if (y0 < e->sy) {
+      x0 += (x1-x0) * (e->sy - y0) / (y1-y0);
+      y0 = e->sy;
+   }
+   if (y1 > e->ey) {
+      x1 += (x1-x0) * (e->ey - y1) / (y1-y0);
+      y1 = e->ey;
+   }
+
+   if (x0 == x)
+      STBTT_assert(x1 <= x+1);
+   else if (x0 == x+1)
+      STBTT_assert(x1 >= x);
+   else if (x0 <= x)
+      STBTT_assert(x1 <= x);
+   else if (x0 >= x+1)
+      STBTT_assert(x1 >= x+1);
+   else
+      STBTT_assert(x1 >= x && x1 <= x+1);
+
+   if (x0 <= x && x1 <= x)
+      scanline[x] += e->direction * (y1-y0);
+   else if (x0 >= x+1 && x1 >= x+1)
+      ;
+   else {
+      STBTT_assert(x0 >= x && x0 <= x+1 && x1 >= x && x1 <= x+1);
+      scanline[x] += e->direction * (y1-y0) * (1-((x0-x)+(x1-x))/2); // coverage = 1 - average x position
+   }
+}
+
+static void stbtt__fill_active_edges_new(float *scanline, float *scanline_fill, int len, stbtt__active_edge *e, float y_top)
+{
+   float y_bottom = y_top+1;
+
+   while (e) {
+      // brute force every pixel
+
+      // compute intersection points with top & bottom
+      STBTT_assert(e->ey >= y_top);
+
+      if (e->fdx == 0) {
+         float x0 = e->fx;
+         if (x0 < len) {
+            if (x0 >= 0) {
+               stbtt__handle_clipped_edge(scanline,(int) x0,e, x0,y_top, x0,y_bottom);
+               stbtt__handle_clipped_edge(scanline_fill-1,(int) x0+1,e, x0,y_top, x0,y_bottom);
+            } else {
+               stbtt__handle_clipped_edge(scanline_fill-1,0,e, x0,y_top, x0,y_bottom);
+            }
+         }
+      } else {
+         float x0 = e->fx;
+         float dx = e->fdx;
+         float xb = x0 + dx;
+         float x_top, x_bottom;
+         float sy0,sy1;
+         float dy = e->fdy;
+         STBTT_assert(e->sy <= y_bottom && e->ey >= y_top);
+
+         // compute endpoints of line segment clipped to this scanline (if the
+         // line segment starts on this scanline. x0 is the intersection of the
+         // line with y_top, but that may be off the line segment.
+         if (e->sy > y_top) {
+            x_top = x0 + dx * (e->sy - y_top);
+            sy0 = e->sy;
+         } else {
+            x_top = x0;
+            sy0 = y_top;
+         }
+         if (e->ey < y_bottom) {
+            x_bottom = x0 + dx * (e->ey - y_top);
+            sy1 = e->ey;
+         } else {
+            x_bottom = xb;
+            sy1 = y_bottom;
+         }
+
+         if (x_top >= 0 && x_bottom >= 0 && x_top < len && x_bottom < len) {
+            // from here on, we don't have to range check x values
+
+            if ((int) x_top == (int) x_bottom) {
+               float height;
+               // simple case, only spans one pixel
+               int x = (int) x_top;
+               height = sy1 - sy0;
+               STBTT_assert(x >= 0 && x < len);
+               scanline[x] += e->direction * (1-((x_top - x) + (x_bottom-x))/2)  * height;
+               scanline_fill[x] += e->direction * height; // everything right of this pixel is filled
+            } else {
+               int x,x1,x2;
+               float y_crossing, step, sign, area;
+               // covers 2+ pixels
+               if (x_top > x_bottom) {
+                  // flip scanline vertically; signed area is the same
+                  float t;
+                  sy0 = y_bottom - (sy0 - y_top);
+                  sy1 = y_bottom - (sy1 - y_top);
+                  t = sy0, sy0 = sy1, sy1 = t;
+                  t = x_bottom, x_bottom = x_top, x_top = t;
+                  dx = -dx;
+                  dy = -dy;
+                  t = x0, x0 = xb, xb = t;
+                  // [DEAR IMGUI] Fix static analyzer warning
+                  (void)dx; // [ImGui: fix static analyzer warning]
+               }
+
+               x1 = (int) x_top;
+               x2 = (int) x_bottom;
+               // compute intersection with y axis at x1+1
+               y_crossing = (x1+1 - x0) * dy + y_top;
+
+               sign = e->direction;
+               // area of the rectangle covered from y0..y_crossing
+               area = sign * (y_crossing-sy0);
+               // area of the triangle (x_top,y0), (x+1,y0), (x+1,y_crossing)
+               scanline[x1] += area * (1-((x_top - x1)+(x1+1-x1))/2);
+
+               step = sign * dy;
+               for (x = x1+1; x < x2; ++x) {
+                  scanline[x] += area + step/2;
+                  area += step;
+               }
+               y_crossing += dy * (x2 - (x1+1));
+
+               STBTT_assert(STBTT_fabs(area) <= 1.01f);
+
+               scanline[x2] += area + sign * (1-((x2-x2)+(x_bottom-x2))/2) * (sy1-y_crossing);
+
+               scanline_fill[x2] += sign * (sy1-sy0);
+            }
+         } else {
+            // if edge goes outside of box we're drawing, we require
+            // clipping logic. since this does not match the intended use
+            // of this library, we use a different, very slow brute
+            // force implementation
+            int x;
+            for (x=0; x < len; ++x) {
+               // cases:
+               //
+               // there can be up to two intersections with the pixel. any intersection
+               // with left or right edges can be handled by splitting into two (or three)
+               // regions. intersections with top & bottom do not necessitate case-wise logic.
+               //
+               // the old way of doing this found the intersections with the left & right edges,
+               // then used some simple logic to produce up to three segments in sorted order
+               // from top-to-bottom. however, this had a problem: if an x edge was epsilon
+               // across the x border, then the corresponding y position might not be distinct
+               // from the other y segment, and it might ignored as an empty segment. to avoid
+               // that, we need to explicitly produce segments based on x positions.
+
+               // rename variables to clearly-defined pairs
+               float y0 = y_top;
+               float x1 = (float) (x);
+               float x2 = (float) (x+1);
+               float x3 = xb;
+               float y3 = y_bottom;
+
+               // x = e->x + e->dx * (y-y_top)
+               // (y-y_top) = (x - e->x) / e->dx
+               // y = (x - e->x) / e->dx + y_top
+               float y1 = (x - x0) / dx + y_top;
+               float y2 = (x+1 - x0) / dx + y_top;
+
+               if (x0 < x1 && x3 > x2) {         // three segments descending down-right
+                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x1,y1);
+                  stbtt__handle_clipped_edge(scanline,x,e, x1,y1, x2,y2);
+                  stbtt__handle_clipped_edge(scanline,x,e, x2,y2, x3,y3);
+               } else if (x3 < x1 && x0 > x2) {  // three segments descending down-left
+                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x2,y2);
+                  stbtt__handle_clipped_edge(scanline,x,e, x2,y2, x1,y1);
+                  stbtt__handle_clipped_edge(scanline,x,e, x1,y1, x3,y3);
+               } else if (x0 < x1 && x3 > x1) {  // two segments across x, down-right
+                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x1,y1);
+                  stbtt__handle_clipped_edge(scanline,x,e, x1,y1, x3,y3);
+               } else if (x3 < x1 && x0 > x1) {  // two segments across x, down-left
+                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x1,y1);
+                  stbtt__handle_clipped_edge(scanline,x,e, x1,y1, x3,y3);
+               } else if (x0 < x2 && x3 > x2) {  // two segments across x+1, down-right
+                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x2,y2);
+                  stbtt__handle_clipped_edge(scanline,x,e, x2,y2, x3,y3);
+               } else if (x3 < x2 && x0 > x2) {  // two segments across x+1, down-left
+                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x2,y2);
+                  stbtt__handle_clipped_edge(scanline,x,e, x2,y2, x3,y3);
+               } else {  // one segment
+                  stbtt__handle_clipped_edge(scanline,x,e, x0,y0, x3,y3);
+               }
+            }
+         }
+      }
+      e = e->next;
+   }
+}
+
+// directly AA rasterize edges w/o supersampling
+static void stbtt__rasterize_sorted_edges(stbtt__bitmap *result, stbtt__edge *e, int n, int vsubsample, int off_x, int off_y, void *userdata)
+{
+   stbtt__hheap hh = { 0, 0, 0 };
+   stbtt__active_edge *active = NULL;
+   int y,j=0, i;
+   float scanline_data[129], *scanline, *scanline2;
+
+   STBTT__NOTUSED(vsubsample);
+
+   if (result->w > 64)
+      scanline = (float *) STBTT_malloc((result->w*2+1) * sizeof(float), userdata);
+   else
+      scanline = scanline_data;
+
+   scanline2 = scanline + result->w;
+
+   y = off_y;
+   e[n].y0 = (float) (off_y + result->h) + 1;
+
+   while (j < result->h) {
+      // find center of pixel for this scanline
+      float scan_y_top    = y + 0.0f;
+      float scan_y_bottom = y + 1.0f;
+      stbtt__active_edge **step = &active;
+
+      STBTT_memset(scanline , 0, result->w*sizeof(scanline[0]));
+      STBTT_memset(scanline2, 0, (result->w+1)*sizeof(scanline[0]));
+
+      // update all active edges;
+      // remove all active edges that terminate before the top of this scanline
+      while (*step) {
+         stbtt__active_edge * z = *step;
+         if (z->ey <= scan_y_top) {
+            *step = z->next; // delete from list
+            STBTT_assert(z->direction);
+            z->direction = 0;
+            stbtt__hheap_free(&hh, z);
+         } else {
+            step = &((*step)->next); // advance through list
+         }
+      }
+
+      // insert all edges that start before the bottom of this scanline
+      while (e->y0 <= scan_y_bottom) {
+         if (e->y0 != e->y1) {
+            stbtt__active_edge *z = stbtt__new_active(&hh, e, off_x, scan_y_top, userdata);
+            if (z != NULL) {
+               if (j == 0 && off_y != 0) {
+                  if (z->ey < scan_y_top) {
+                     // this can happen due to subpixel positioning and some kind of fp rounding error i think
+                     z->ey = scan_y_top;
+                  }
+               }
+               STBTT_assert(z->ey >= scan_y_top); // if we get really unlucky a tiny bit of an edge can be out of bounds
+               // insert at front
+               z->next = active;
+               active = z;
+            }
+         }
+         ++e;
+      }
+
+      // now process all active edges
+      if (active)
+         stbtt__fill_active_edges_new(scanline, scanline2+1, result->w, active, scan_y_top);
+
+      {
+         float sum = 0;
+         for (i=0; i < result->w; ++i) {
+            float k;
+            int m;
+            sum += scanline2[i];
+            k = scanline[i] + sum;
+            k = (float) STBTT_fabs(k)*255 + 0.5f;
+            m = (int) k;
+            if (m > 255) m = 255;
+            result->pixels[j*result->stride + i] = (unsigned char) m;
+         }
+      }
+      // advance all the edges
+      step = &active;
+      while (*step) {
+         stbtt__active_edge *z = *step;
+         z->fx += z->fdx; // advance to position for current scanline
+         step = &((*step)->next); // advance through list
+      }
+
+      ++y;
+      ++j;
+   }
+
+   stbtt__hheap_cleanup(&hh, userdata);
+
+   if (scanline != scanline_data)
+      STBTT_free(scanline, userdata);
+}
+#else
+#error "Unrecognized value of STBTT_RASTERIZER_VERSION"
+#endif
+
+#define STBTT__COMPARE(a,b)  ((a)->y0 < (b)->y0)
+
+static void stbtt__sort_edges_ins_sort(stbtt__edge *p, int n)
+{
+   int i,j;
+   for (i=1; i < n; ++i) {
+      stbtt__edge t = p[i], *a = &t;
+      j = i;
+      while (j > 0) {
+         stbtt__edge *b = &p[j-1];
+         int c = STBTT__COMPARE(a,b);
+         if (!c) break;
+         p[j] = p[j-1];
+         --j;
+      }
+      if (i != j)
+         p[j] = t;
+   }
+}
+
+static void stbtt__sort_edges_quicksort(stbtt__edge *p, int n)
+{
+   /* threshold for transitioning to insertion sort */
+   while (n > 12) {
+      stbtt__edge t;
+      int c01,c12,c,m,i,j;
+
+      /* compute median of three */
+      m = n >> 1;
+      c01 = STBTT__COMPARE(&p[0],&p[m]);
+      c12 = STBTT__COMPARE(&p[m],&p[n-1]);
+      /* if 0 >= mid >= end, or 0 < mid < end, then use mid */
+      if (c01 != c12) {
+         /* otherwise, we'll need to swap something else to middle */
+         int z;
+         c = STBTT__COMPARE(&p[0],&p[n-1]);
+         /* 0>mid && mid<n:  0>n => n; 0<n => 0 */
+         /* 0<mid && mid>n:  0>n => 0; 0<n => n */
+         z = (c == c12) ? 0 : n-1;
+         t = p[z];
+         p[z] = p[m];
+         p[m] = t;
+      }
+      /* now p[m] is the median-of-three */
+      /* swap it to the beginning so it won't move around */
+      t = p[0];
+      p[0] = p[m];
+      p[m] = t;
+
+      /* partition loop */
+      i=1;
+      j=n-1;
+      for(;;) {
+         /* handling of equality is crucial here */
+         /* for sentinels & efficiency with duplicates */
+         for (;;++i) {
+            if (!STBTT__COMPARE(&p[i], &p[0])) break;
+         }
+         for (;;--j) {
+            if (!STBTT__COMPARE(&p[0], &p[j])) break;
+         }
+         /* make sure we haven't crossed */
+         if (i >= j) break;
+         t = p[i];
+         p[i] = p[j];
+         p[j] = t;
+
+         ++i;
+         --j;
+      }
+      /* recurse on smaller side, iterate on larger */
+      if (j < (n-i)) {
+         stbtt__sort_edges_quicksort(p,j);
+         p = p+i;
+         n = n-i;
+      } else {
+         stbtt__sort_edges_quicksort(p+i, n-i);
+         n = j;
+      }
+   }
+}
+
+static void stbtt__sort_edges(stbtt__edge *p, int n)
+{
+   stbtt__sort_edges_quicksort(p, n);
+   stbtt__sort_edges_ins_sort(p, n);
+}
+
+typedef struct
+{
+   float x,y;
+} stbtt__point;
+
+static void stbtt__rasterize(stbtt__bitmap *result, stbtt__point *pts, int *wcount, int windings, float scale_x, float scale_y, float shift_x, float shift_y, int off_x, int off_y, int invert, void *userdata)
+{
+   float y_scale_inv = invert ? -scale_y : scale_y;
+   stbtt__edge *e;
+   int n,i,j,k,m;
+#if STBTT_RASTERIZER_VERSION == 1
+   int vsubsample = result->h < 8 ? 15 : 5;
+#elif STBTT_RASTERIZER_VERSION == 2
+   int vsubsample = 1;
+#else
+   #error "Unrecognized value of STBTT_RASTERIZER_VERSION"
+#endif
+   // vsubsample should divide 255 evenly; otherwise we won't reach full opacity
+
+   // now we have to blow out the windings into explicit edge lists
+   n = 0;
+   for (i=0; i < windings; ++i)
+      n += wcount[i];
+
+   e = (stbtt__edge *) STBTT_malloc(sizeof(*e) * (n+1), userdata); // add an extra one as a sentinel
+   if (e == 0) return;
+   n = 0;
+
+   m=0;
+   for (i=0; i < windings; ++i) {
+      stbtt__point *p = pts + m;
+      m += wcount[i];
+      j = wcount[i]-1;
+      for (k=0; k < wcount[i]; j=k++) {
+         int a=k,b=j;
+         // skip the edge if horizontal
+         if (p[j].y == p[k].y)
+            continue;
+         // add edge from j to k to the list
+         e[n].invert = 0;
+         if (invert ? p[j].y > p[k].y : p[j].y < p[k].y) {
+            e[n].invert = 1;
+            a=j,b=k;
+         }
+         e[n].x0 = p[a].x * scale_x + shift_x;
+         e[n].y0 = (p[a].y * y_scale_inv + shift_y) * vsubsample;
+         e[n].x1 = p[b].x * scale_x + shift_x;
+         e[n].y1 = (p[b].y * y_scale_inv + shift_y) * vsubsample;
+         ++n;
+      }
+   }
+
+   // now sort the edges by their highest point (should snap to integer, and then by x)
+   //STBTT_sort(e, n, sizeof(e[0]), stbtt__edge_compare);
+   stbtt__sort_edges(e, n);
+
+   // now, traverse the scanlines and find the intersections on each scanline, use xor winding rule
+   stbtt__rasterize_sorted_edges(result, e, n, vsubsample, off_x, off_y, userdata);
+
+   STBTT_free(e, userdata);
+}
+
+static void stbtt__add_point(stbtt__point *points, int n, float x, float y)
+{
+   if (!points) return; // during first pass, it's unallocated
+   points[n].x = x;
+   points[n].y = y;
+}
+
+// tessellate until threshold p is happy... @TODO warped to compensate for non-linear stretching
+static int stbtt__tesselate_curve(stbtt__point *points, int *num_points, float x0, float y0, float x1, float y1, float x2, float y2, float objspace_flatness_squared, int n)
+{
+   // midpoint
+   float mx = (x0 + 2*x1 + x2)/4;
+   float my = (y0 + 2*y1 + y2)/4;
+   // versus directly drawn line
+   float dx = (x0+x2)/2 - mx;
+   float dy = (y0+y2)/2 - my;
+   if (n > 16) // 65536 segments on one curve better be enough!
+      return 1;
+   if (dx*dx+dy*dy > objspace_flatness_squared) { // half-pixel error allowed... need to be smaller if AA
+      stbtt__tesselate_curve(points, num_points, x0,y0, (x0+x1)/2.0f,(y0+y1)/2.0f, mx,my, objspace_flatness_squared,n+1);
+      stbtt__tesselate_curve(points, num_points, mx,my, (x1+x2)/2.0f,(y1+y2)/2.0f, x2,y2, objspace_flatness_squared,n+1);
+   } else {
+      stbtt__add_point(points, *num_points,x2,y2);
+      *num_points = *num_points+1;
+   }
+   return 1;
+}
+
+static void stbtt__tesselate_cubic(stbtt__point *points, int *num_points, float x0, float y0, float x1, float y1, float x2, float y2, float x3, float y3, float objspace_flatness_squared, int n)
+{
+   // @TODO this "flatness" calculation is just made-up nonsense that seems to work well enough
+   float dx0 = x1-x0;
+   float dy0 = y1-y0;
+   float dx1 = x2-x1;
+   float dy1 = y2-y1;
+   float dx2 = x3-x2;
+   float dy2 = y3-y2;
+   float dx = x3-x0;
+   float dy = y3-y0;
+   float longlen = (float) (STBTT_sqrt(dx0*dx0+dy0*dy0)+STBTT_sqrt(dx1*dx1+dy1*dy1)+STBTT_sqrt(dx2*dx2+dy2*dy2));
+   float shortlen = (float) STBTT_sqrt(dx*dx+dy*dy);
+   float flatness_squared = longlen*longlen-shortlen*shortlen;
+
+   if (n > 16) // 65536 segments on one curve better be enough!
+      return;
+
+   if (flatness_squared > objspace_flatness_squared) {
+      float x01 = (x0+x1)/2;
+      float y01 = (y0+y1)/2;
+      float x12 = (x1+x2)/2;
+      float y12 = (y1+y2)/2;
+      float x23 = (x2+x3)/2;
+      float y23 = (y2+y3)/2;
+
+      float xa = (x01+x12)/2;
+      float ya = (y01+y12)/2;
+      float xb = (x12+x23)/2;
+      float yb = (y12+y23)/2;
+
+      float mx = (xa+xb)/2;
+      float my = (ya+yb)/2;
+
+      stbtt__tesselate_cubic(points, num_points, x0,y0, x01,y01, xa,ya, mx,my, objspace_flatness_squared,n+1);
+      stbtt__tesselate_cubic(points, num_points, mx,my, xb,yb, x23,y23, x3,y3, objspace_flatness_squared,n+1);
+   } else {
+      stbtt__add_point(points, *num_points,x3,y3);
+      *num_points = *num_points+1;
+   }
+}
+
+// returns number of contours
+static stbtt__point *stbtt_FlattenCurves(stbtt_vertex *vertices, int num_verts, float objspace_flatness, int **contour_lengths, int *num_contours, void *userdata)
+{
+   stbtt__point *points=0;
+   int num_points=0;
+
+   float objspace_flatness_squared = objspace_flatness * objspace_flatness;
+   int i,n=0,start=0, pass;
+
+   // count how many "moves" there are to get the contour count
+   for (i=0; i < num_verts; ++i)
+      if (vertices[i].type == STBTT_vmove)
+         ++n;
+
+   *num_contours = n;
+   if (n == 0) return 0;
+
+   *contour_lengths = (int *) STBTT_malloc(sizeof(**contour_lengths) * n, userdata);
+
+   if (*contour_lengths == 0) {
+      *num_contours = 0;
+      return 0;
+   }
+
+   // make two passes through the points so we don't need to realloc
+   for (pass=0; pass < 2; ++pass) {
+      float x=0,y=0;
+      if (pass == 1) {
+         points = (stbtt__point *) STBTT_malloc(num_points * sizeof(points[0]), userdata);
+         if (points == NULL) goto error;
+      }
+      num_points = 0;
+      n= -1;
+      for (i=0; i < num_verts; ++i) {
+         switch (vertices[i].type) {
+            case STBTT_vmove:
+               // start the next contour
+               if (n >= 0)
+                  (*contour_lengths)[n] = num_points - start;
+               ++n;
+               start = num_points;
+
+               x = vertices[i].x, y = vertices[i].y;
+               stbtt__add_point(points, num_points++, x,y);
+               break;
+            case STBTT_vline:
+               x = vertices[i].x, y = vertices[i].y;
+               stbtt__add_point(points, num_points++, x, y);
+               break;
+            case STBTT_vcurve:
+               stbtt__tesselate_curve(points, &num_points, x,y,
+                                        vertices[i].cx, vertices[i].cy,
+                                        vertices[i].x,  vertices[i].y,
+                                        objspace_flatness_squared, 0);
+               x = vertices[i].x, y = vertices[i].y;
+               break;
+            case STBTT_vcubic:
+               stbtt__tesselate_cubic(points, &num_points, x,y,
+                                        vertices[i].cx, vertices[i].cy,
+                                        vertices[i].cx1, vertices[i].cy1,
+                                        vertices[i].x,  vertices[i].y,
+                                        objspace_flatness_squared, 0);
+               x = vertices[i].x, y = vertices[i].y;
+               break;
+         }
+      }
+      (*contour_lengths)[n] = num_points - start;
+   }
+
+   return points;
+error:
+   STBTT_free(points, userdata);
+   STBTT_free(*contour_lengths, userdata);
+   *contour_lengths = 0;
+   *num_contours = 0;
+   return NULL;
+}
+
+STBTT_DEF void stbtt_Rasterize(stbtt__bitmap *result, float flatness_in_pixels, stbtt_vertex *vertices, int num_verts, float scale_x, float scale_y, float shift_x, float shift_y, int x_off, int y_off, int invert, void *userdata)
+{
+   float scale            = scale_x > scale_y ? scale_y : scale_x;
+   int winding_count      = 0;
+   int *winding_lengths   = NULL;
+   stbtt__point *windings = stbtt_FlattenCurves(vertices, num_verts, flatness_in_pixels / scale, &winding_lengths, &winding_count, userdata);
+   if (windings) {
+      stbtt__rasterize(result, windings, winding_lengths, winding_count, scale_x, scale_y, shift_x, shift_y, x_off, y_off, invert, userdata);
+      STBTT_free(winding_lengths, userdata);
+      STBTT_free(windings, userdata);
+   }
+}
+
+STBTT_DEF void stbtt_FreeBitmap(unsigned char *bitmap, void *userdata)
+{
+   STBTT_free(bitmap, userdata);
+}
+
+STBTT_DEF unsigned char *stbtt_GetGlyphBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int glyph, int *width, int *height, int *xoff, int *yoff)
+{
+   int ix0,iy0,ix1,iy1;
+   stbtt__bitmap gbm;
+   stbtt_vertex *vertices;   
+   int num_verts = stbtt_GetGlyphShape(info, glyph, &vertices);
+
+   if (scale_x == 0) scale_x = scale_y;
+   if (scale_y == 0) {
+      if (scale_x == 0) {
+         STBTT_free(vertices, info->userdata);
+         return NULL;
+      }
+      scale_y = scale_x;
+   }
+
+   stbtt_GetGlyphBitmapBoxSubpixel(info, glyph, scale_x, scale_y, shift_x, shift_y, &ix0,&iy0,&ix1,&iy1);
+
+   // now we get the size
+   gbm.w = (ix1 - ix0);
+   gbm.h = (iy1 - iy0);
+   gbm.pixels = NULL; // in case we error
+
+   if (width ) *width  = gbm.w;
+   if (height) *height = gbm.h;
+   if (xoff  ) *xoff   = ix0;
+   if (yoff  ) *yoff   = iy0;
+   
+   if (gbm.w && gbm.h) {
+      gbm.pixels = (unsigned char *) STBTT_malloc(gbm.w * gbm.h, info->userdata);
+      if (gbm.pixels) {
+         gbm.stride = gbm.w;
+
+         stbtt_Rasterize(&gbm, 0.35f, vertices, num_verts, scale_x, scale_y, shift_x, shift_y, ix0, iy0, 1, info->userdata);
+      }
+   }
+   STBTT_free(vertices, info->userdata);
+   return gbm.pixels;
+}   
+
+STBTT_DEF unsigned char *stbtt_GetGlyphBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int glyph, int *width, int *height, int *xoff, int *yoff)
+{
+   return stbtt_GetGlyphBitmapSubpixel(info, scale_x, scale_y, 0.0f, 0.0f, glyph, width, height, xoff, yoff);
+}
+
+STBTT_DEF void stbtt_MakeGlyphBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int glyph)
+{
+   int ix0,iy0;
+   stbtt_vertex *vertices;
+   int num_verts = stbtt_GetGlyphShape(info, glyph, &vertices);
+   stbtt__bitmap gbm;   
+
+   stbtt_GetGlyphBitmapBoxSubpixel(info, glyph, scale_x, scale_y, shift_x, shift_y, &ix0,&iy0,0,0);
+   gbm.pixels = output;
+   gbm.w = out_w;
+   gbm.h = out_h;
+   gbm.stride = out_stride;
+
+   if (gbm.w && gbm.h)
+      stbtt_Rasterize(&gbm, 0.35f, vertices, num_verts, scale_x, scale_y, shift_x, shift_y, ix0,iy0, 1, info->userdata);
+
+   STBTT_free(vertices, info->userdata);
+}
+
+STBTT_DEF void stbtt_MakeGlyphBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int glyph)
+{
+   stbtt_MakeGlyphBitmapSubpixel(info, output, out_w, out_h, out_stride, scale_x, scale_y, 0.0f,0.0f, glyph);
+}
+
+STBTT_DEF unsigned char *stbtt_GetCodepointBitmapSubpixel(const stbtt_fontinfo *info, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint, int *width, int *height, int *xoff, int *yoff)
+{
+   return stbtt_GetGlyphBitmapSubpixel(info, scale_x, scale_y,shift_x,shift_y, stbtt_FindGlyphIndex(info,codepoint), width,height,xoff,yoff);
+}   
+
+STBTT_DEF void stbtt_MakeCodepointBitmapSubpixelPrefilter(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int oversample_x, int oversample_y, float *sub_x, float *sub_y, int codepoint)
+{
+   stbtt_MakeGlyphBitmapSubpixelPrefilter(info, output, out_w, out_h, out_stride, scale_x, scale_y, shift_x, shift_y, oversample_x, oversample_y, sub_x, sub_y, stbtt_FindGlyphIndex(info,codepoint));
+}
+
+STBTT_DEF void stbtt_MakeCodepointBitmapSubpixel(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int codepoint)
+{
+   stbtt_MakeGlyphBitmapSubpixel(info, output, out_w, out_h, out_stride, scale_x, scale_y, shift_x, shift_y, stbtt_FindGlyphIndex(info,codepoint));
+}
+
+STBTT_DEF unsigned char *stbtt_GetCodepointBitmap(const stbtt_fontinfo *info, float scale_x, float scale_y, int codepoint, int *width, int *height, int *xoff, int *yoff)
+{
+   return stbtt_GetCodepointBitmapSubpixel(info, scale_x, scale_y, 0.0f,0.0f, codepoint, width,height,xoff,yoff);
+}   
+
+STBTT_DEF void stbtt_MakeCodepointBitmap(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, int codepoint)
+{
+   stbtt_MakeCodepointBitmapSubpixel(info, output, out_w, out_h, out_stride, scale_x, scale_y, 0.0f,0.0f, codepoint);
+}
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// bitmap baking
+//
+// This is SUPER-CRAPPY packing to keep source code small
+
+static int stbtt_BakeFontBitmap_internal(unsigned char *data, int offset,  // font location (use offset=0 for plain .ttf)
+                                float pixel_height,                     // height of font in pixels
+                                unsigned char *pixels, int pw, int ph,  // bitmap to be filled in
+                                int first_char, int num_chars,          // characters to bake
+                                stbtt_bakedchar *chardata)
+{
+   float scale;
+   int x,y,bottom_y, i;
+   stbtt_fontinfo f;
+   f.userdata = NULL;
+   if (!stbtt_InitFont(&f, data, offset))
+      return -1;
+   STBTT_memset(pixels, 0, pw*ph); // background of 0 around pixels
+   x=y=1;
+   bottom_y = 1;
+
+   scale = stbtt_ScaleForPixelHeight(&f, pixel_height);
+
+   for (i=0; i < num_chars; ++i) {
+      int advance, lsb, x0,y0,x1,y1,gw,gh;
+      int g = stbtt_FindGlyphIndex(&f, first_char + i);
+      stbtt_GetGlyphHMetrics(&f, g, &advance, &lsb);
+      stbtt_GetGlyphBitmapBox(&f, g, scale,scale, &x0,&y0,&x1,&y1);
+      gw = x1-x0;
+      gh = y1-y0;
+      if (x + gw + 1 >= pw)
+         y = bottom_y, x = 1; // advance to next row
+      if (y + gh + 1 >= ph) // check if it fits vertically AFTER potentially moving to next row
+         return -i;
+      STBTT_assert(x+gw < pw);
+      STBTT_assert(y+gh < ph);
+      stbtt_MakeGlyphBitmap(&f, pixels+x+y*pw, gw,gh,pw, scale,scale, g);
+      chardata[i].x0 = (stbtt_int16) x;
+      chardata[i].y0 = (stbtt_int16) y;
+      chardata[i].x1 = (stbtt_int16) (x + gw);
+      chardata[i].y1 = (stbtt_int16) (y + gh);
+      chardata[i].xadvance = scale * advance;
+      chardata[i].xoff     = (float) x0;
+      chardata[i].yoff     = (float) y0;
+      x = x + gw + 1;
+      if (y+gh+1 > bottom_y)
+         bottom_y = y+gh+1;
+   }
+   return bottom_y;
+}
+
+STBTT_DEF void stbtt_GetBakedQuad(const stbtt_bakedchar *chardata, int pw, int ph, int char_index, float *xpos, float *ypos, stbtt_aligned_quad *q, int opengl_fillrule)
+{
+   float d3d_bias = opengl_fillrule ? 0 : -0.5f;
+   float ipw = 1.0f / pw, iph = 1.0f / ph;
+   const stbtt_bakedchar *b = chardata + char_index;
+   int round_x = STBTT_ifloor((*xpos + b->xoff) + 0.5f);
+   int round_y = STBTT_ifloor((*ypos + b->yoff) + 0.5f);
+
+   q->x0 = round_x + d3d_bias;
+   q->y0 = round_y + d3d_bias;
+   q->x1 = round_x + b->x1 - b->x0 + d3d_bias;
+   q->y1 = round_y + b->y1 - b->y0 + d3d_bias;
+
+   q->s0 = b->x0 * ipw;
+   q->t0 = b->y0 * iph;
+   q->s1 = b->x1 * ipw;
+   q->t1 = b->y1 * iph;
+
+   *xpos += b->xadvance;
+}
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// rectangle packing replacement routines if you don't have stb_rect_pack.h
+//
+
+#ifndef STB_RECT_PACK_VERSION
+
+typedef int stbrp_coord;
+
+////////////////////////////////////////////////////////////////////////////////////
+//                                                                                //
+//                                                                                //
+// COMPILER WARNING ?!?!?                                                         //
+//                                                                                //
+//                                                                                //
+// if you get a compile warning due to these symbols being defined more than      //
+// once, move #include "stb_rect_pack.h" before #include "stb_truetype.h"         //
+//                                                                                //
+////////////////////////////////////////////////////////////////////////////////////
+
+typedef struct
+{
+   int width,height;
+   int x,y,bottom_y;
+} stbrp_context;
+
+typedef struct
+{
+   unsigned char x;
+} stbrp_node;
+
+struct stbrp_rect
+{
+   stbrp_coord x,y;
+   int id,w,h,was_packed;
+};
+
+static void stbrp_init_target(stbrp_context *con, int pw, int ph, stbrp_node *nodes, int num_nodes)
+{
+   con->width  = pw;
+   con->height = ph;
+   con->x = 0;
+   con->y = 0;
+   con->bottom_y = 0;
+   STBTT__NOTUSED(nodes);
+   STBTT__NOTUSED(num_nodes);   
+}
+
+static void stbrp_pack_rects(stbrp_context *con, stbrp_rect *rects, int num_rects)
+{
+   int i;
+   for (i=0; i < num_rects; ++i) {
+      if (con->x + rects[i].w > con->width) {
+         con->x = 0;
+         con->y = con->bottom_y;
+      }
+      if (con->y + rects[i].h > con->height)
+         break;
+      rects[i].x = con->x;
+      rects[i].y = con->y;
+      rects[i].was_packed = 1;
+      con->x += rects[i].w;
+      if (con->y + rects[i].h > con->bottom_y)
+         con->bottom_y = con->y + rects[i].h;
+   }
+   for (   ; i < num_rects; ++i)
+      rects[i].was_packed = 0;
+}
+#endif
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// bitmap baking
+//
+// This is SUPER-AWESOME (tm Ryan Gordon) packing using stb_rect_pack.h. If
+// stb_rect_pack.h isn't available, it uses the BakeFontBitmap strategy.
+
+STBTT_DEF int stbtt_PackBegin(stbtt_pack_context *spc, unsigned char *pixels, int pw, int ph, int stride_in_bytes, int padding, void *alloc_context)
+{
+   stbrp_context *context = (stbrp_context *) STBTT_malloc(sizeof(*context)            ,alloc_context);
+   int            num_nodes = pw - padding;
+   stbrp_node    *nodes   = (stbrp_node    *) STBTT_malloc(sizeof(*nodes  ) * num_nodes,alloc_context);
+
+   if (context == NULL || nodes == NULL) {
+      if (context != NULL) STBTT_free(context, alloc_context);
+      if (nodes   != NULL) STBTT_free(nodes  , alloc_context);
+      return 0;
+   }
+
+   spc->user_allocator_context = alloc_context;
+   spc->width = pw;
+   spc->height = ph;
+   spc->pixels = pixels;
+   spc->pack_info = context;
+   spc->nodes = nodes;
+   spc->padding = padding;
+   spc->stride_in_bytes = stride_in_bytes != 0 ? stride_in_bytes : pw;
+   spc->h_oversample = 1;
+   spc->v_oversample = 1;
+   spc->skip_missing = 0;
+
+   stbrp_init_target(context, pw-padding, ph-padding, nodes, num_nodes);
+
+   if (pixels)
+      STBTT_memset(pixels, 0, pw*ph); // background of 0 around pixels
+
+   return 1;
+}
+
+STBTT_DEF void stbtt_PackEnd  (stbtt_pack_context *spc)
+{
+   STBTT_free(spc->nodes    , spc->user_allocator_context);
+   STBTT_free(spc->pack_info, spc->user_allocator_context);
+}
+
+STBTT_DEF void stbtt_PackSetOversampling(stbtt_pack_context *spc, unsigned int h_oversample, unsigned int v_oversample)
+{
+   STBTT_assert(h_oversample <= STBTT_MAX_OVERSAMPLE);
+   STBTT_assert(v_oversample <= STBTT_MAX_OVERSAMPLE);
+   if (h_oversample <= STBTT_MAX_OVERSAMPLE)
+      spc->h_oversample = h_oversample;
+   if (v_oversample <= STBTT_MAX_OVERSAMPLE)
+      spc->v_oversample = v_oversample;
+}
+
+STBTT_DEF void stbtt_PackSetSkipMissingCodepoints(stbtt_pack_context *spc, int skip)
+{
+   spc->skip_missing = skip;
+}
+
+#define STBTT__OVER_MASK  (STBTT_MAX_OVERSAMPLE-1)
+
+static void stbtt__h_prefilter(unsigned char *pixels, int w, int h, int stride_in_bytes, unsigned int kernel_width)
+{
+   unsigned char buffer[STBTT_MAX_OVERSAMPLE];
+   int safe_w = w - kernel_width;
+   int j;
+   STBTT_memset(buffer, 0, STBTT_MAX_OVERSAMPLE); // suppress bogus warning from VS2013 -analyze
+   for (j=0; j < h; ++j) {
+      int i;
+      unsigned int total;
+      STBTT_memset(buffer, 0, kernel_width);
+
+      total = 0;
+
+      // make kernel_width a constant in common cases so compiler can optimize out the divide
+      switch (kernel_width) {
+         case 2:
+            for (i=0; i <= safe_w; ++i) {
+               total += pixels[i] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i];
+               pixels[i] = (unsigned char) (total / 2);
+            }
+            break;
+         case 3:
+            for (i=0; i <= safe_w; ++i) {
+               total += pixels[i] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i];
+               pixels[i] = (unsigned char) (total / 3);
+            }
+            break;
+         case 4:
+            for (i=0; i <= safe_w; ++i) {
+               total += pixels[i] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i];
+               pixels[i] = (unsigned char) (total / 4);
+            }
+            break;
+         case 5:
+            for (i=0; i <= safe_w; ++i) {
+               total += pixels[i] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i];
+               pixels[i] = (unsigned char) (total / 5);
+            }
+            break;
+         default:
+            for (i=0; i <= safe_w; ++i) {
+               total += pixels[i] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i];
+               pixels[i] = (unsigned char) (total / kernel_width);
+            }
+            break;
+      }
+
+      for (; i < w; ++i) {
+         STBTT_assert(pixels[i] == 0);
+         total -= buffer[i & STBTT__OVER_MASK];
+         pixels[i] = (unsigned char) (total / kernel_width);
+      }
+
+      pixels += stride_in_bytes;
+   }
+}
+
+static void stbtt__v_prefilter(unsigned char *pixels, int w, int h, int stride_in_bytes, unsigned int kernel_width)
+{
+   unsigned char buffer[STBTT_MAX_OVERSAMPLE];
+   int safe_h = h - kernel_width;
+   int j;
+   STBTT_memset(buffer, 0, STBTT_MAX_OVERSAMPLE); // suppress bogus warning from VS2013 -analyze
+   for (j=0; j < w; ++j) {
+      int i;
+      unsigned int total;
+      STBTT_memset(buffer, 0, kernel_width);
+
+      total = 0;
+
+      // make kernel_width a constant in common cases so compiler can optimize out the divide
+      switch (kernel_width) {
+         case 2:
+            for (i=0; i <= safe_h; ++i) {
+               total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
+               pixels[i*stride_in_bytes] = (unsigned char) (total / 2);
+            }
+            break;
+         case 3:
+            for (i=0; i <= safe_h; ++i) {
+               total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
+               pixels[i*stride_in_bytes] = (unsigned char) (total / 3);
+            }
+            break;
+         case 4:
+            for (i=0; i <= safe_h; ++i) {
+               total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
+               pixels[i*stride_in_bytes] = (unsigned char) (total / 4);
+            }
+            break;
+         case 5:
+            for (i=0; i <= safe_h; ++i) {
+               total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
+               pixels[i*stride_in_bytes] = (unsigned char) (total / 5);
+            }
+            break;
+         default:
+            for (i=0; i <= safe_h; ++i) {
+               total += pixels[i*stride_in_bytes] - buffer[i & STBTT__OVER_MASK];
+               buffer[(i+kernel_width) & STBTT__OVER_MASK] = pixels[i*stride_in_bytes];
+               pixels[i*stride_in_bytes] = (unsigned char) (total / kernel_width);
+            }
+            break;
+      }
+
+      for (; i < h; ++i) {
+         STBTT_assert(pixels[i*stride_in_bytes] == 0);
+         total -= buffer[i & STBTT__OVER_MASK];
+         pixels[i*stride_in_bytes] = (unsigned char) (total / kernel_width);
+      }
+
+      pixels += 1;
+   }
+}
+
+static float stbtt__oversample_shift(int oversample)
+{
+   if (!oversample)
+      return 0.0f;
+
+   // The prefilter is a box filter of width "oversample",
+   // which shifts phase by (oversample - 1)/2 pixels in
+   // oversampled space. We want to shift in the opposite
+   // direction to counter this.
+   return (float)-(oversample - 1) / (2.0f * (float)oversample);
+}
+
+// rects array must be big enough to accommodate all characters in the given ranges
+STBTT_DEF int stbtt_PackFontRangesGatherRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects)
+{
+   int i,j,k;
+
+   k=0;
+   for (i=0; i < num_ranges; ++i) {
+      float fh = ranges[i].font_size;
+      float scale = fh > 0 ? stbtt_ScaleForPixelHeight(info, fh) : stbtt_ScaleForMappingEmToPixels(info, -fh);
+      ranges[i].h_oversample = (unsigned char) spc->h_oversample;
+      ranges[i].v_oversample = (unsigned char) spc->v_oversample;
+      for (j=0; j < ranges[i].num_chars; ++j) {
+         int x0,y0,x1,y1;
+         int codepoint = ranges[i].array_of_unicode_codepoints == NULL ? ranges[i].first_unicode_codepoint_in_range + j : ranges[i].array_of_unicode_codepoints[j];
+         int glyph = stbtt_FindGlyphIndex(info, codepoint);
+         if (glyph == 0 && spc->skip_missing) {
+            rects[k].w = rects[k].h = 0;
+         } else {
+            stbtt_GetGlyphBitmapBoxSubpixel(info,glyph,
+                                            scale * spc->h_oversample,
+                                            scale * spc->v_oversample,
+                                            0,0,
+                                            &x0,&y0,&x1,&y1);
+            rects[k].w = (stbrp_coord) (x1-x0 + spc->padding + spc->h_oversample-1);
+            rects[k].h = (stbrp_coord) (y1-y0 + spc->padding + spc->v_oversample-1);
+         }
+         ++k;
+      }
+   }
+
+   return k;
+}
+
+STBTT_DEF void stbtt_MakeGlyphBitmapSubpixelPrefilter(const stbtt_fontinfo *info, unsigned char *output, int out_w, int out_h, int out_stride, float scale_x, float scale_y, float shift_x, float shift_y, int prefilter_x, int prefilter_y, float *sub_x, float *sub_y, int glyph)
+{
+   stbtt_MakeGlyphBitmapSubpixel(info,
+                                 output,
+                                 out_w - (prefilter_x - 1),
+                                 out_h - (prefilter_y - 1),
+                                 out_stride,
+                                 scale_x,
+                                 scale_y,
+                                 shift_x,
+                                 shift_y,
+                                 glyph);
+
+   if (prefilter_x > 1)
+      stbtt__h_prefilter(output, out_w, out_h, out_stride, prefilter_x);
+
+   if (prefilter_y > 1)
+      stbtt__v_prefilter(output, out_w, out_h, out_stride, prefilter_y);
+
+   *sub_x = stbtt__oversample_shift(prefilter_x);
+   *sub_y = stbtt__oversample_shift(prefilter_y);
+}
+
+// rects array must be big enough to accommodate all characters in the given ranges
+STBTT_DEF int stbtt_PackFontRangesRenderIntoRects(stbtt_pack_context *spc, const stbtt_fontinfo *info, stbtt_pack_range *ranges, int num_ranges, stbrp_rect *rects)
+{
+   int i,j,k, return_value = 1;
+
+   // save current values
+   int old_h_over = spc->h_oversample;
+   int old_v_over = spc->v_oversample;
+
+   k = 0;
+   for (i=0; i < num_ranges; ++i) {
+      float fh = ranges[i].font_size;
+      float scale = fh > 0 ? stbtt_ScaleForPixelHeight(info, fh) : stbtt_ScaleForMappingEmToPixels(info, -fh);
+      float recip_h,recip_v,sub_x,sub_y;
+      spc->h_oversample = ranges[i].h_oversample;
+      spc->v_oversample = ranges[i].v_oversample;
+      recip_h = 1.0f / spc->h_oversample;
+      recip_v = 1.0f / spc->v_oversample;
+      sub_x = stbtt__oversample_shift(spc->h_oversample);
+      sub_y = stbtt__oversample_shift(spc->v_oversample);
+      for (j=0; j < ranges[i].num_chars; ++j) {
+         stbrp_rect *r = &rects[k];
+         if (r->was_packed && r->w != 0 && r->h != 0) {
+            stbtt_packedchar *bc = &ranges[i].chardata_for_range[j];
+            int advance, lsb, x0,y0,x1,y1;
+            int codepoint = ranges[i].array_of_unicode_codepoints == NULL ? ranges[i].first_unicode_codepoint_in_range + j : ranges[i].array_of_unicode_codepoints[j];
+            int glyph = stbtt_FindGlyphIndex(info, codepoint);
+            stbrp_coord pad = (stbrp_coord) spc->padding;
+
+            // pad on left and top
+            r->x += pad;
+            r->y += pad;
+            r->w -= pad;
+            r->h -= pad;
+            stbtt_GetGlyphHMetrics(info, glyph, &advance, &lsb);
+            stbtt_GetGlyphBitmapBox(info, glyph,
+                                    scale * spc->h_oversample,
+                                    scale * spc->v_oversample,
+                                    &x0,&y0,&x1,&y1);
+            stbtt_MakeGlyphBitmapSubpixel(info,
+                                          spc->pixels + r->x + r->y*spc->stride_in_bytes,
+                                          r->w - spc->h_oversample+1,
+                                          r->h - spc->v_oversample+1,
+                                          spc->stride_in_bytes,
+                                          scale * spc->h_oversample,
+                                          scale * spc->v_oversample,
+                                          0,0,
+                                          glyph);
+
+            if (spc->h_oversample > 1)
+               stbtt__h_prefilter(spc->pixels + r->x + r->y*spc->stride_in_bytes,
+                                  r->w, r->h, spc->stride_in_bytes,
+                                  spc->h_oversample);
+
+            if (spc->v_oversample > 1)
+               stbtt__v_prefilter(spc->pixels + r->x + r->y*spc->stride_in_bytes,
+                                  r->w, r->h, spc->stride_in_bytes,
+                                  spc->v_oversample);
+
+            bc->x0       = (stbtt_int16)  r->x;
+            bc->y0       = (stbtt_int16)  r->y;
+            bc->x1       = (stbtt_int16) (r->x + r->w);
+            bc->y1       = (stbtt_int16) (r->y + r->h);
+            bc->xadvance =                scale * advance;
+            bc->xoff     =       (float)  x0 * recip_h + sub_x;
+            bc->yoff     =       (float)  y0 * recip_v + sub_y;
+            bc->xoff2    =                (x0 + r->w) * recip_h + sub_x;
+            bc->yoff2    =                (y0 + r->h) * recip_v + sub_y;
+         } else {
+            return_value = 0; // if any fail, report failure
+         }
+
+         ++k;
+      }
+   }
+
+   // restore original values
+   spc->h_oversample = old_h_over;
+   spc->v_oversample = old_v_over;
+
+   return return_value;
+}
+
+STBTT_DEF void stbtt_PackFontRangesPackRects(stbtt_pack_context *spc, stbrp_rect *rects, int num_rects)
+{
+   stbrp_pack_rects((stbrp_context *) spc->pack_info, rects, num_rects);
+}
+
+STBTT_DEF int stbtt_PackFontRanges(stbtt_pack_context *spc, const unsigned char *fontdata, int font_index, stbtt_pack_range *ranges, int num_ranges)
+{
+   stbtt_fontinfo info;
+   int i,j,n, return_value; // [DEAR IMGUI] removed = 1
+   //stbrp_context *context = (stbrp_context *) spc->pack_info;
+   stbrp_rect    *rects;
+
+   // flag all characters as NOT packed
+   for (i=0; i < num_ranges; ++i)
+      for (j=0; j < ranges[i].num_chars; ++j)
+         ranges[i].chardata_for_range[j].x0 =
+         ranges[i].chardata_for_range[j].y0 =
+         ranges[i].chardata_for_range[j].x1 =
+         ranges[i].chardata_for_range[j].y1 = 0;
+
+   n = 0;
+   for (i=0; i < num_ranges; ++i)
+      n += ranges[i].num_chars;
+         
+   rects = (stbrp_rect *) STBTT_malloc(sizeof(*rects) * n, spc->user_allocator_context);
+   if (rects == NULL)
+      return 0;
+
+   info.userdata = spc->user_allocator_context;
+   stbtt_InitFont(&info, fontdata, stbtt_GetFontOffsetForIndex(fontdata,font_index));
+
+   n = stbtt_PackFontRangesGatherRects(spc, &info, ranges, num_ranges, rects);
+
+   stbtt_PackFontRangesPackRects(spc, rects, n);
+  
+   return_value = stbtt_PackFontRangesRenderIntoRects(spc, &info, ranges, num_ranges, rects);
+
+   STBTT_free(rects, spc->user_allocator_context);
+   return return_value;
+}
+
+STBTT_DEF int stbtt_PackFontRange(stbtt_pack_context *spc, const unsigned char *fontdata, int font_index, float font_size,
+            int first_unicode_codepoint_in_range, int num_chars_in_range, stbtt_packedchar *chardata_for_range)
+{
+   stbtt_pack_range range;
+   range.first_unicode_codepoint_in_range = first_unicode_codepoint_in_range;
+   range.array_of_unicode_codepoints = NULL;
+   range.num_chars                   = num_chars_in_range;
+   range.chardata_for_range          = chardata_for_range;
+   range.font_size                   = font_size;
+   return stbtt_PackFontRanges(spc, fontdata, font_index, &range, 1);
+}
+
+STBTT_DEF void stbtt_GetScaledFontVMetrics(const unsigned char *fontdata, int index, float size, float *ascent, float *descent, float *lineGap)
+{
+   int i_ascent, i_descent, i_lineGap;
+   float scale;
+   stbtt_fontinfo info;
+   stbtt_InitFont(&info, fontdata, stbtt_GetFontOffsetForIndex(fontdata, index));
+   scale = size > 0 ? stbtt_ScaleForPixelHeight(&info, size) : stbtt_ScaleForMappingEmToPixels(&info, -size);
+   stbtt_GetFontVMetrics(&info, &i_ascent, &i_descent, &i_lineGap);
+   *ascent  = (float) i_ascent  * scale;
+   *descent = (float) i_descent * scale;
+   *lineGap = (float) i_lineGap * scale;
+}
+
+STBTT_DEF void stbtt_GetPackedQuad(const stbtt_packedchar *chardata, int pw, int ph, int char_index, float *xpos, float *ypos, stbtt_aligned_quad *q, int align_to_integer)
+{
+   float ipw = 1.0f / pw, iph = 1.0f / ph;
+   const stbtt_packedchar *b = chardata + char_index;
+
+   if (align_to_integer) {
+      float x = (float) STBTT_ifloor((*xpos + b->xoff) + 0.5f);
+      float y = (float) STBTT_ifloor((*ypos + b->yoff) + 0.5f);
+      q->x0 = x;
+      q->y0 = y;
+      q->x1 = x + b->xoff2 - b->xoff;
+      q->y1 = y + b->yoff2 - b->yoff;
+   } else {
+      q->x0 = *xpos + b->xoff;
+      q->y0 = *ypos + b->yoff;
+      q->x1 = *xpos + b->xoff2;
+      q->y1 = *ypos + b->yoff2;
+   }
+
+   q->s0 = b->x0 * ipw;
+   q->t0 = b->y0 * iph;
+   q->s1 = b->x1 * ipw;
+   q->t1 = b->y1 * iph;
+
+   *xpos += b->xadvance;
+}
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// sdf computation
+//
+
+#define STBTT_min(a,b)  ((a) < (b) ? (a) : (b))
+#define STBTT_max(a,b)  ((a) < (b) ? (b) : (a))
+
+static int stbtt__ray_intersect_bezier(float orig[2], float ray[2], float q0[2], float q1[2], float q2[2], float hits[2][2])
+{
+   float q0perp = q0[1]*ray[0] - q0[0]*ray[1];
+   float q1perp = q1[1]*ray[0] - q1[0]*ray[1];
+   float q2perp = q2[1]*ray[0] - q2[0]*ray[1];
+   float roperp = orig[1]*ray[0] - orig[0]*ray[1];
+
+   float a = q0perp - 2*q1perp + q2perp;
+   float b = q1perp - q0perp;
+   float c = q0perp - roperp;
+
+   float s0 = 0., s1 = 0.;
+   int num_s = 0;
+
+   if (a != 0.0) {
+      float discr = b*b - a*c;
+      if (discr > 0.0) {
+         float rcpna = -1 / a;
+         float d = (float) STBTT_sqrt(discr);
+         s0 = (b+d) * rcpna;
+         s1 = (b-d) * rcpna;
+         if (s0 >= 0.0 && s0 <= 1.0)
+            num_s = 1;
+         if (d > 0.0 && s1 >= 0.0 && s1 <= 1.0) {
+            if (num_s == 0) s0 = s1;
+            ++num_s;
+         }
+      }
+   } else {
+      // 2*b*s + c = 0
+      // s = -c / (2*b)
+      s0 = c / (-2 * b);
+      if (s0 >= 0.0 && s0 <= 1.0)
+         num_s = 1;
+   }
+
+   if (num_s == 0)
+      return 0;
+   else {
+      float rcp_len2 = 1 / (ray[0]*ray[0] + ray[1]*ray[1]);
+      float rayn_x = ray[0] * rcp_len2, rayn_y = ray[1] * rcp_len2;
+
+      float q0d =   q0[0]*rayn_x +   q0[1]*rayn_y;
+      float q1d =   q1[0]*rayn_x +   q1[1]*rayn_y;
+      float q2d =   q2[0]*rayn_x +   q2[1]*rayn_y;
+      float rod = orig[0]*rayn_x + orig[1]*rayn_y;
+
+      float q10d = q1d - q0d;
+      float q20d = q2d - q0d;
+      float q0rd = q0d - rod;
+
+      hits[0][0] = q0rd + s0*(2.0f - 2.0f*s0)*q10d + s0*s0*q20d;
+      hits[0][1] = a*s0+b;
+
+      if (num_s > 1) {
+         hits[1][0] = q0rd + s1*(2.0f - 2.0f*s1)*q10d + s1*s1*q20d;
+         hits[1][1] = a*s1+b;
+         return 2;
+      } else {
+         return 1;
+      }
+   }
+}
+
+static int equal(float *a, float *b)
+{
+   return (a[0] == b[0] && a[1] == b[1]);
+}
+
+static int stbtt__compute_crossings_x(float x, float y, int nverts, stbtt_vertex *verts)
+{
+   int i;
+   float orig[2], ray[2] = { 1, 0 };
+   float y_frac;
+   int winding = 0;
+
+   orig[0] = x;
+   //orig[1] = y; // [DEAR IMGUI] commmented double assignment
+
+   // make sure y never passes through a vertex of the shape
+   y_frac = (float) STBTT_fmod(y, 1.0f);
+   if (y_frac < 0.01f)
+      y += 0.01f;
+   else if (y_frac > 0.99f)
+      y -= 0.01f;
+   orig[1] = y;
+
+   // test a ray from (-infinity,y) to (x,y)
+   for (i=0; i < nverts; ++i) {
+      if (verts[i].type == STBTT_vline) {
+         int x0 = (int) verts[i-1].x, y0 = (int) verts[i-1].y;
+         int x1 = (int) verts[i  ].x, y1 = (int) verts[i  ].y;
+         if (y > STBTT_min(y0,y1) && y < STBTT_max(y0,y1) && x > STBTT_min(x0,x1)) {
+            float x_inter = (y - y0) / (y1 - y0) * (x1-x0) + x0;
+            if (x_inter < x)  
+               winding += (y0 < y1) ? 1 : -1;
+         }
+      }
+      if (verts[i].type == STBTT_vcurve) {
+         int x0 = (int) verts[i-1].x , y0 = (int) verts[i-1].y ;
+         int x1 = (int) verts[i  ].cx, y1 = (int) verts[i  ].cy;
+         int x2 = (int) verts[i  ].x , y2 = (int) verts[i  ].y ;
+         int ax = STBTT_min(x0,STBTT_min(x1,x2)), ay = STBTT_min(y0,STBTT_min(y1,y2));
+         int by = STBTT_max(y0,STBTT_max(y1,y2));
+         if (y > ay && y < by && x > ax) {
+            float q0[2],q1[2],q2[2];
+            float hits[2][2];
+            q0[0] = (float)x0;
+            q0[1] = (float)y0;
+            q1[0] = (float)x1;
+            q1[1] = (float)y1;
+            q2[0] = (float)x2;
+            q2[1] = (float)y2;
+            if (equal(q0,q1) || equal(q1,q2)) {
+               x0 = (int)verts[i-1].x;
+               y0 = (int)verts[i-1].y;
+               x1 = (int)verts[i  ].x;
+               y1 = (int)verts[i  ].y;
+               if (y > STBTT_min(y0,y1) && y < STBTT_max(y0,y1) && x > STBTT_min(x0,x1)) {
+                  float x_inter = (y - y0) / (y1 - y0) * (x1-x0) + x0;
+                  if (x_inter < x)  
+                     winding += (y0 < y1) ? 1 : -1;
+               }
+            } else {
+               int num_hits = stbtt__ray_intersect_bezier(orig, ray, q0, q1, q2, hits);
+               if (num_hits >= 1)
+                  if (hits[0][0] < 0)
+                     winding += (hits[0][1] < 0 ? -1 : 1);
+               if (num_hits >= 2)
+                  if (hits[1][0] < 0)
+                     winding += (hits[1][1] < 0 ? -1 : 1);
+            }
+         } 
+      }
+   }
+   return winding;
+}
+
+static float stbtt__cuberoot( float x )
+{
+   if (x<0)
+      return -(float) STBTT_pow(-x,1.0f/3.0f);
+   else
+      return  (float) STBTT_pow( x,1.0f/3.0f);
+}
+
+// x^3 + c*x^2 + b*x + a = 0
+static int stbtt__solve_cubic(float a, float b, float c, float* r)
+{
+	float s = -a / 3;
+	float p = b - a*a / 3;
+	float q = a * (2*a*a - 9*b) / 27 + c;
+   float p3 = p*p*p;
+	float d = q*q + 4*p3 / 27;
+	if (d >= 0) {
+		float z = (float) STBTT_sqrt(d);
+		float u = (-q + z) / 2;
+		float v = (-q - z) / 2;
+		u = stbtt__cuberoot(u);
+		v = stbtt__cuberoot(v);
+		r[0] = s + u + v;
+		return 1;
+	} else {
+	   float u = (float) STBTT_sqrt(-p/3);
+	   float v = (float) STBTT_acos(-STBTT_sqrt(-27/p3) * q / 2) / 3; // p3 must be negative, since d is negative
+	   float m = (float) STBTT_cos(v);
+      float n = (float) STBTT_cos(v-3.141592/2)*1.732050808f;
+	   r[0] = s + u * 2 * m;
+	   r[1] = s - u * (m + n);
+	   r[2] = s - u * (m - n);
+
+      //STBTT_assert( STBTT_fabs(((r[0]+a)*r[0]+b)*r[0]+c) < 0.05f);  // these asserts may not be safe at all scales, though they're in bezier t parameter units so maybe?
+      //STBTT_assert( STBTT_fabs(((r[1]+a)*r[1]+b)*r[1]+c) < 0.05f);
+      //STBTT_assert( STBTT_fabs(((r[2]+a)*r[2]+b)*r[2]+c) < 0.05f);
+   	return 3;
+   }
+}
+
+STBTT_DEF unsigned char * stbtt_GetGlyphSDF(const stbtt_fontinfo *info, float scale, int glyph, int padding, unsigned char onedge_value, float pixel_dist_scale, int *width, int *height, int *xoff, int *yoff)
+{
+   float scale_x = scale, scale_y = scale;
+   int ix0,iy0,ix1,iy1;
+   int w,h;
+   unsigned char *data;
+
+   // if one scale is 0, use same scale for both
+   if (scale_x == 0) scale_x = scale_y;
+   if (scale_y == 0) {
+      if (scale_x == 0) return NULL;  // if both scales are 0, return NULL
+      scale_y = scale_x;
+   }
+
+   stbtt_GetGlyphBitmapBoxSubpixel(info, glyph, scale, scale, 0.0f,0.0f, &ix0,&iy0,&ix1,&iy1);
+
+   // if empty, return NULL
+   if (ix0 == ix1 || iy0 == iy1)
+      return NULL;
+
+   ix0 -= padding;
+   iy0 -= padding;
+   ix1 += padding;
+   iy1 += padding;
+
+   w = (ix1 - ix0);
+   h = (iy1 - iy0);
+
+   if (width ) *width  = w;
+   if (height) *height = h;
+   if (xoff  ) *xoff   = ix0;
+   if (yoff  ) *yoff   = iy0;
+
+   // invert for y-downwards bitmaps
+   scale_y = -scale_y;
+      
+   {
+      int x,y,i,j;
+      float *precompute;
+      stbtt_vertex *verts;
+      int num_verts = stbtt_GetGlyphShape(info, glyph, &verts);
+      data = (unsigned char *) STBTT_malloc(w * h, info->userdata);
+      precompute = (float *) STBTT_malloc(num_verts * sizeof(float), info->userdata);
+
+      for (i=0,j=num_verts-1; i < num_verts; j=i++) {
+         if (verts[i].type == STBTT_vline) {
+            float x0 = verts[i].x*scale_x, y0 = verts[i].y*scale_y;
+            float x1 = verts[j].x*scale_x, y1 = verts[j].y*scale_y;
+            float dist = (float) STBTT_sqrt((x1-x0)*(x1-x0) + (y1-y0)*(y1-y0));
+            precompute[i] = (dist == 0) ? 0.0f : 1.0f / dist;
+         } else if (verts[i].type == STBTT_vcurve) {
+            float x2 = verts[j].x *scale_x, y2 = verts[j].y *scale_y;
+            float x1 = verts[i].cx*scale_x, y1 = verts[i].cy*scale_y;
+            float x0 = verts[i].x *scale_x, y0 = verts[i].y *scale_y;
+            float bx = x0 - 2*x1 + x2, by = y0 - 2*y1 + y2;
+            float len2 = bx*bx + by*by;
+            if (len2 != 0.0f)
+               precompute[i] = 1.0f / (bx*bx + by*by);
+            else
+               precompute[i] = 0.0f;
+         } else
+            precompute[i] = 0.0f;
+      }
+
+      for (y=iy0; y < iy1; ++y) {
+         for (x=ix0; x < ix1; ++x) {
+            float val;
+            float min_dist = 999999.0f;
+            float sx = (float) x + 0.5f;
+            float sy = (float) y + 0.5f;
+            float x_gspace = (sx / scale_x);
+            float y_gspace = (sy / scale_y);
+
+            int winding = stbtt__compute_crossings_x(x_gspace, y_gspace, num_verts, verts); // @OPTIMIZE: this could just be a rasterization, but needs to be line vs. non-tesselated curves so a new path
+
+            for (i=0; i < num_verts; ++i) {
+               float x0 = verts[i].x*scale_x, y0 = verts[i].y*scale_y;
+
+               // check against every point here rather than inside line/curve primitives -- @TODO: wrong if multiple 'moves' in a row produce a garbage point, and given culling, probably more efficient to do within line/curve
+               float dist2 = (x0-sx)*(x0-sx) + (y0-sy)*(y0-sy);
+               if (dist2 < min_dist*min_dist)
+                  min_dist = (float) STBTT_sqrt(dist2);
+
+               if (verts[i].type == STBTT_vline) {
+                  float x1 = verts[i-1].x*scale_x, y1 = verts[i-1].y*scale_y;
+
+                  // coarse culling against bbox
+                  //if (sx > STBTT_min(x0,x1)-min_dist && sx < STBTT_max(x0,x1)+min_dist &&
+                  //    sy > STBTT_min(y0,y1)-min_dist && sy < STBTT_max(y0,y1)+min_dist)
+                  float dist = (float) STBTT_fabs((x1-x0)*(y0-sy) - (y1-y0)*(x0-sx)) * precompute[i];
+                  STBTT_assert(i != 0);
+                  if (dist < min_dist) {
+                     // check position along line
+                     // x' = x0 + t*(x1-x0), y' = y0 + t*(y1-y0)
+                     // minimize (x'-sx)*(x'-sx)+(y'-sy)*(y'-sy)
+                     float dx = x1-x0, dy = y1-y0;
+                     float px = x0-sx, py = y0-sy;
+                     // minimize (px+t*dx)^2 + (py+t*dy)^2 = px*px + 2*px*dx*t + t^2*dx*dx + py*py + 2*py*dy*t + t^2*dy*dy
+                     // derivative: 2*px*dx + 2*py*dy + (2*dx*dx+2*dy*dy)*t, set to 0 and solve
+                     float t = -(px*dx + py*dy) / (dx*dx + dy*dy);
+                     if (t >= 0.0f && t <= 1.0f)
+                        min_dist = dist;
+                  }
+               } else if (verts[i].type == STBTT_vcurve) {
+                  float x2 = verts[i-1].x *scale_x, y2 = verts[i-1].y *scale_y;
+                  float x1 = verts[i  ].cx*scale_x, y1 = verts[i  ].cy*scale_y;
+                  float box_x0 = STBTT_min(STBTT_min(x0,x1),x2);
+                  float box_y0 = STBTT_min(STBTT_min(y0,y1),y2);
+                  float box_x1 = STBTT_max(STBTT_max(x0,x1),x2);
+                  float box_y1 = STBTT_max(STBTT_max(y0,y1),y2);
+                  // coarse culling against bbox to avoid computing cubic unnecessarily
+                  if (sx > box_x0-min_dist && sx < box_x1+min_dist && sy > box_y0-min_dist && sy < box_y1+min_dist) {
+                     int num=0;
+                     float ax = x1-x0, ay = y1-y0;
+                     float bx = x0 - 2*x1 + x2, by = y0 - 2*y1 + y2;
+                     float mx = x0 - sx, my = y0 - sy;
+                     float res[3],px,py,t,it;
+                     float a_inv = precompute[i];
+                     if (a_inv == 0.0) { // if a_inv is 0, it's 2nd degree so use quadratic formula
+                        float a = 3*(ax*bx + ay*by);
+                        float b = 2*(ax*ax + ay*ay) + (mx*bx+my*by);
+                        float c = mx*ax+my*ay;
+                        if (a == 0.0) { // if a is 0, it's linear
+                           if (b != 0.0) {
+                              res[num++] = -c/b;
+                           }
+                        } else {
+                           float discriminant = b*b - 4*a*c;
+                           if (discriminant < 0)
+                              num = 0;
+                           else {
+                              float root = (float) STBTT_sqrt(discriminant);
+                              res[0] = (-b - root)/(2*a);
+                              res[1] = (-b + root)/(2*a);
+                              num = 2; // don't bother distinguishing 1-solution case, as code below will still work
+                           }
+                        }
+                     } else {
+                        float b = 3*(ax*bx + ay*by) * a_inv; // could precompute this as it doesn't depend on sample point
+                        float c = (2*(ax*ax + ay*ay) + (mx*bx+my*by)) * a_inv;
+                        float d = (mx*ax+my*ay) * a_inv;
+                        num = stbtt__solve_cubic(b, c, d, res);
+                     }
+                     if (num >= 1 && res[0] >= 0.0f && res[0] <= 1.0f) {
+                        t = res[0], it = 1.0f - t;
+                        px = it*it*x0 + 2*t*it*x1 + t*t*x2;
+                        py = it*it*y0 + 2*t*it*y1 + t*t*y2;
+                        dist2 = (px-sx)*(px-sx) + (py-sy)*(py-sy);
+                        if (dist2 < min_dist * min_dist)
+                           min_dist = (float) STBTT_sqrt(dist2);
+                     }
+                     if (num >= 2 && res[1] >= 0.0f && res[1] <= 1.0f) {
+                        t = res[1], it = 1.0f - t;
+                        px = it*it*x0 + 2*t*it*x1 + t*t*x2;
+                        py = it*it*y0 + 2*t*it*y1 + t*t*y2;
+                        dist2 = (px-sx)*(px-sx) + (py-sy)*(py-sy);
+                        if (dist2 < min_dist * min_dist)
+                           min_dist = (float) STBTT_sqrt(dist2);
+                     }
+                     if (num >= 3 && res[2] >= 0.0f && res[2] <= 1.0f) {
+                        t = res[2], it = 1.0f - t;
+                        px = it*it*x0 + 2*t*it*x1 + t*t*x2;
+                        py = it*it*y0 + 2*t*it*y1 + t*t*y2;
+                        dist2 = (px-sx)*(px-sx) + (py-sy)*(py-sy);
+                        if (dist2 < min_dist * min_dist)
+                           min_dist = (float) STBTT_sqrt(dist2);
+                     }
+                  }
+               }
+            }
+            if (winding == 0)
+               min_dist = -min_dist;  // if outside the shape, value is negative
+            val = onedge_value + pixel_dist_scale * min_dist;
+            if (val < 0)
+               val = 0;
+            else if (val > 255)
+               val = 255;
+            data[(y-iy0)*w+(x-ix0)] = (unsigned char) val;
+         }
+      }
+      STBTT_free(precompute, info->userdata);
+      STBTT_free(verts, info->userdata);
+   }
+   return data;
+}   
+
+STBTT_DEF unsigned char * stbtt_GetCodepointSDF(const stbtt_fontinfo *info, float scale, int codepoint, int padding, unsigned char onedge_value, float pixel_dist_scale, int *width, int *height, int *xoff, int *yoff)
+{
+   return stbtt_GetGlyphSDF(info, scale, stbtt_FindGlyphIndex(info, codepoint), padding, onedge_value, pixel_dist_scale, width, height, xoff, yoff);
+}
+
+STBTT_DEF void stbtt_FreeSDF(unsigned char *bitmap, void *userdata)
+{
+   STBTT_free(bitmap, userdata);
+}
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// font name matching -- recommended not to use this
+//
+
+// check if a utf8 string contains a prefix which is the utf16 string; if so return length of matching utf8 string
+static stbtt_int32 stbtt__CompareUTF8toUTF16_bigendian_prefix(stbtt_uint8 *s1, stbtt_int32 len1, stbtt_uint8 *s2, stbtt_int32 len2) 
+{
+   stbtt_int32 i=0;
+
+   // convert utf16 to utf8 and compare the results while converting
+   while (len2) {
+      stbtt_uint16 ch = s2[0]*256 + s2[1];
+      if (ch < 0x80) {
+         if (i >= len1) return -1;
+         if (s1[i++] != ch) return -1;
+      } else if (ch < 0x800) {
+         if (i+1 >= len1) return -1;
+         if (s1[i++] != 0xc0 + (ch >> 6)) return -1;
+         if (s1[i++] != 0x80 + (ch & 0x3f)) return -1;
+      } else if (ch >= 0xd800 && ch < 0xdc00) {
+         stbtt_uint32 c;
+         stbtt_uint16 ch2 = s2[2]*256 + s2[3];
+         if (i+3 >= len1) return -1;
+         c = ((ch - 0xd800) << 10) + (ch2 - 0xdc00) + 0x10000;
+         if (s1[i++] != 0xf0 + (c >> 18)) return -1;
+         if (s1[i++] != 0x80 + ((c >> 12) & 0x3f)) return -1;
+         if (s1[i++] != 0x80 + ((c >>  6) & 0x3f)) return -1;
+         if (s1[i++] != 0x80 + ((c      ) & 0x3f)) return -1;
+         s2 += 2; // plus another 2 below
+         len2 -= 2;
+      } else if (ch >= 0xdc00 && ch < 0xe000) {
+         return -1;
+      } else {
+         if (i+2 >= len1) return -1;
+         if (s1[i++] != 0xe0 + (ch >> 12)) return -1;
+         if (s1[i++] != 0x80 + ((ch >> 6) & 0x3f)) return -1;
+         if (s1[i++] != 0x80 + ((ch     ) & 0x3f)) return -1;
+      }
+      s2 += 2;
+      len2 -= 2;
+   }
+   return i;
+}
+
+static int stbtt_CompareUTF8toUTF16_bigendian_internal(char *s1, int len1, char *s2, int len2) 
+{
+   return len1 == stbtt__CompareUTF8toUTF16_bigendian_prefix((stbtt_uint8*) s1, len1, (stbtt_uint8*) s2, len2);
+}
+
+// returns results in whatever encoding you request... but note that 2-byte encodings
+// will be BIG-ENDIAN... use stbtt_CompareUTF8toUTF16_bigendian() to compare
+STBTT_DEF const char *stbtt_GetFontNameString(const stbtt_fontinfo *font, int *length, int platformID, int encodingID, int languageID, int nameID)
+{
+   stbtt_int32 i,count,stringOffset;
+   stbtt_uint8 *fc = font->data;
+   stbtt_uint32 offset = font->fontstart;
+   stbtt_uint32 nm = stbtt__find_table(fc, offset, "name");
+   if (!nm) return NULL;
+
+   count = ttUSHORT(fc+nm+2);
+   stringOffset = nm + ttUSHORT(fc+nm+4);
+   for (i=0; i < count; ++i) {
+      stbtt_uint32 loc = nm + 6 + 12 * i;
+      if (platformID == ttUSHORT(fc+loc+0) && encodingID == ttUSHORT(fc+loc+2)
+          && languageID == ttUSHORT(fc+loc+4) && nameID == ttUSHORT(fc+loc+6)) {
+         *length = ttUSHORT(fc+loc+8);
+         return (const char *) (fc+stringOffset+ttUSHORT(fc+loc+10));
+      }
+   }
+   return NULL;
+}
+
+static int stbtt__matchpair(stbtt_uint8 *fc, stbtt_uint32 nm, stbtt_uint8 *name, stbtt_int32 nlen, stbtt_int32 target_id, stbtt_int32 next_id)
+{
+   stbtt_int32 i;
+   stbtt_int32 count = ttUSHORT(fc+nm+2);
+   stbtt_int32 stringOffset = nm + ttUSHORT(fc+nm+4);
+
+   for (i=0; i < count; ++i) {
+      stbtt_uint32 loc = nm + 6 + 12 * i;
+      stbtt_int32 id = ttUSHORT(fc+loc+6);
+      if (id == target_id) {
+         // find the encoding
+         stbtt_int32 platform = ttUSHORT(fc+loc+0), encoding = ttUSHORT(fc+loc+2), language = ttUSHORT(fc+loc+4);
+
+         // is this a Unicode encoding?
+         if (platform == 0 || (platform == 3 && encoding == 1) || (platform == 3 && encoding == 10)) {
+            stbtt_int32 slen = ttUSHORT(fc+loc+8);
+            stbtt_int32 off = ttUSHORT(fc+loc+10);
+
+            // check if there's a prefix match
+            stbtt_int32 matchlen = stbtt__CompareUTF8toUTF16_bigendian_prefix(name, nlen, fc+stringOffset+off,slen);
+            if (matchlen >= 0) {
+               // check for target_id+1 immediately following, with same encoding & language
+               if (i+1 < count && ttUSHORT(fc+loc+12+6) == next_id && ttUSHORT(fc+loc+12) == platform && ttUSHORT(fc+loc+12+2) == encoding && ttUSHORT(fc+loc+12+4) == language) {
+                  slen = ttUSHORT(fc+loc+12+8);
+                  off = ttUSHORT(fc+loc+12+10);
+                  if (slen == 0) {
+                     if (matchlen == nlen)
+                        return 1;
+                  } else if (matchlen < nlen && name[matchlen] == ' ') {
+                     ++matchlen;
+                     if (stbtt_CompareUTF8toUTF16_bigendian_internal((char*) (name+matchlen), nlen-matchlen, (char*)(fc+stringOffset+off),slen))
+                        return 1;
+                  }
+               } else {
+                  // if nothing immediately following
+                  if (matchlen == nlen)
+                     return 1;
+               }
+            }
+         }
+
+         // @TODO handle other encodings
+      }
+   }
+   return 0;
+}
+
+static int stbtt__matches(stbtt_uint8 *fc, stbtt_uint32 offset, stbtt_uint8 *name, stbtt_int32 flags)
+{
+   stbtt_int32 nlen = (stbtt_int32) STBTT_strlen((char *) name);
+   stbtt_uint32 nm,hd;
+   if (!stbtt__isfont(fc+offset)) return 0;
+
+   // check italics/bold/underline flags in macStyle...
+   if (flags) {
+      hd = stbtt__find_table(fc, offset, "head");
+      if ((ttUSHORT(fc+hd+44) & 7) != (flags & 7)) return 0;
+   }
+
+   nm = stbtt__find_table(fc, offset, "name");
+   if (!nm) return 0;
+
+   if (flags) {
+      // if we checked the macStyle flags, then just check the family and ignore the subfamily
+      if (stbtt__matchpair(fc, nm, name, nlen, 16, -1))  return 1;
+      if (stbtt__matchpair(fc, nm, name, nlen,  1, -1))  return 1;
+      if (stbtt__matchpair(fc, nm, name, nlen,  3, -1))  return 1;
+   } else {
+      if (stbtt__matchpair(fc, nm, name, nlen, 16, 17))  return 1;
+      if (stbtt__matchpair(fc, nm, name, nlen,  1,  2))  return 1;
+      if (stbtt__matchpair(fc, nm, name, nlen,  3, -1))  return 1;
+   }
+
+   return 0;
+}
+
+static int stbtt_FindMatchingFont_internal(unsigned char *font_collection, char *name_utf8, stbtt_int32 flags)
+{
+   stbtt_int32 i;
+   for (i=0;;++i) {
+      stbtt_int32 off = stbtt_GetFontOffsetForIndex(font_collection, i);
+      if (off < 0) return off;
+      if (stbtt__matches((stbtt_uint8 *) font_collection, off, (stbtt_uint8*) name_utf8, flags))
+         return off;
+   }
+}
+
+#if defined(__GNUC__) || defined(__clang__)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wcast-qual"
+#endif
+
+STBTT_DEF int stbtt_BakeFontBitmap(const unsigned char *data, int offset,
+                                float pixel_height, unsigned char *pixels, int pw, int ph,
+                                int first_char, int num_chars, stbtt_bakedchar *chardata)
+{
+   return stbtt_BakeFontBitmap_internal((unsigned char *) data, offset, pixel_height, pixels, pw, ph, first_char, num_chars, chardata);
+}
+
+STBTT_DEF int stbtt_GetFontOffsetForIndex(const unsigned char *data, int index)
+{
+   return stbtt_GetFontOffsetForIndex_internal((unsigned char *) data, index);   
+}
+
+STBTT_DEF int stbtt_GetNumberOfFonts(const unsigned char *data)
+{
+   return stbtt_GetNumberOfFonts_internal((unsigned char *) data);
+}
+
+STBTT_DEF int stbtt_InitFont(stbtt_fontinfo *info, const unsigned char *data, int offset)
+{
+   return stbtt_InitFont_internal(info, (unsigned char *) data, offset);
+}
+
+STBTT_DEF int stbtt_FindMatchingFont(const unsigned char *fontdata, const char *name, int flags)
+{
+   return stbtt_FindMatchingFont_internal((unsigned char *) fontdata, (char *) name, flags);
+}
+
+STBTT_DEF int stbtt_CompareUTF8toUTF16_bigendian(const char *s1, int len1, const char *s2, int len2)
+{
+   return stbtt_CompareUTF8toUTF16_bigendian_internal((char *) s1, len1, (char *) s2, len2);
+}
+
+#if defined(__GNUC__) || defined(__clang__)
+#pragma GCC diagnostic pop
+#endif
+
+#endif // STB_TRUETYPE_IMPLEMENTATION
+
+
+// FULL VERSION HISTORY
+//
+//   1.19 (2018-02-11) OpenType GPOS kerning (horizontal only), STBTT_fmod
+//   1.18 (2018-01-29) add missing function
+//   1.17 (2017-07-23) make more arguments const; doc fix
+//   1.16 (2017-07-12) SDF support
+//   1.15 (2017-03-03) make more arguments const
+//   1.14 (2017-01-16) num-fonts-in-TTC function
+//   1.13 (2017-01-02) support OpenType fonts, certain Apple fonts
+//   1.12 (2016-10-25) suppress warnings about casting away const with -Wcast-qual
+//   1.11 (2016-04-02) fix unused-variable warning
+//   1.10 (2016-04-02) allow user-defined fabs() replacement
+//                     fix memory leak if fontsize=0.0
+//                     fix warning from duplicate typedef
+//   1.09 (2016-01-16) warning fix; avoid crash on outofmem; use alloc userdata for PackFontRanges
+//   1.08 (2015-09-13) document stbtt_Rasterize(); fixes for vertical & horizontal edges
+//   1.07 (2015-08-01) allow PackFontRanges to accept arrays of sparse codepoints;
+//                     allow PackFontRanges to pack and render in separate phases;
+//                     fix stbtt_GetFontOFfsetForIndex (never worked for non-0 input?);
+//                     fixed an assert() bug in the new rasterizer
+//                     replace assert() with STBTT_assert() in new rasterizer
+//   1.06 (2015-07-14) performance improvements (~35% faster on x86 and x64 on test machine)
+//                     also more precise AA rasterizer, except if shapes overlap
+//                     remove need for STBTT_sort
+//   1.05 (2015-04-15) fix misplaced definitions for STBTT_STATIC
+//   1.04 (2015-04-15) typo in example
+//   1.03 (2015-04-12) STBTT_STATIC, fix memory leak in new packing, various fixes
+//   1.02 (2014-12-10) fix various warnings & compile issues w/ stb_rect_pack, C++
+//   1.01 (2014-12-08) fix subpixel position when oversampling to exactly match
+//                        non-oversampled; STBTT_POINT_SIZE for packed case only
+//   1.00 (2014-12-06) add new PackBegin etc. API, w/ support for oversampling
+//   0.99 (2014-09-18) fix multiple bugs with subpixel rendering (ryg)
+//   0.9  (2014-08-07) support certain mac/iOS fonts without an MS platformID
+//   0.8b (2014-07-07) fix a warning
+//   0.8  (2014-05-25) fix a few more warnings
+//   0.7  (2013-09-25) bugfix: subpixel glyph bug fixed in 0.5 had come back
+//   0.6c (2012-07-24) improve documentation
+//   0.6b (2012-07-20) fix a few more warnings
+//   0.6  (2012-07-17) fix warnings; added stbtt_ScaleForMappingEmToPixels,
+//                        stbtt_GetFontBoundingBox, stbtt_IsGlyphEmpty
+//   0.5  (2011-12-09) bugfixes:
+//                        subpixel glyph renderer computed wrong bounding box
+//                        first vertex of shape can be off-curve (FreeSans)
+//   0.4b (2011-12-03) fixed an error in the font baking example
+//   0.4  (2011-12-01) kerning, subpixel rendering (tor)
+//                    bugfixes for:
+//                        codepoint-to-glyph conversion using table fmt=12
+//                        codepoint-to-glyph conversion using table fmt=4
+//                        stbtt_GetBakedQuad with non-square texture (Zer)
+//                    updated Hello World! sample to use kerning and subpixel
+//                    fixed some warnings
+//   0.3  (2009-06-24) cmap fmt=12, compound shapes (MM)
+//                    userdata, malloc-from-userdata, non-zero fill (stb)
+//   0.2  (2009-03-11) Fix unsigned/signed char warnings
+//   0.1  (2009-03-09) First public release
+//
+
+/*
+------------------------------------------------------------------------------
+This software is available under 2 licenses -- choose whichever you prefer.
+------------------------------------------------------------------------------
+ALTERNATIVE A - MIT License
+Copyright (c) 2017 Sean Barrett
+Permission is hereby granted, free of charge, to any person obtaining a copy of 
+this software and associated documentation files (the "Software"), to deal in 
+the Software without restriction, including without limitation the rights to 
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies 
+of the Software, and to permit persons to whom the Software is furnished to do 
+so, subject to the following conditions:
+The above copyright notice and this permission notice shall be included in all 
+copies or substantial portions of the Software.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 
+SOFTWARE.
+------------------------------------------------------------------------------
+ALTERNATIVE B - Public Domain (www.unlicense.org)
+This is free and unencumbered software released into the public domain.
+Anyone is free to copy, modify, publish, use, compile, sell, or distribute this 
+software, either in source code form or as a compiled binary, for any purpose, 
+commercial or non-commercial, and by any means.
+In jurisdictions that recognize copyright laws, the author or authors of this 
+software dedicate any and all copyright interest in the software to the public 
+domain. We make this dedication for the benefit of the public at large and to 
+the detriment of our heirs and successors. We intend this dedication to be an 
+overt act of relinquishment in perpetuity of all present and future rights to 
+this software under copyright law.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
+AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 
+ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+------------------------------------------------------------------------------
+*/

include/imgui/misc/README.txt

+
+misc/cpp/
+  InputText() wrappers for C++ standard library (STL) type: std::string.
+  This is also an example of how you may wrap your own similar types.
+
+misc/fonts/
+  Fonts loading/merging instructions (e.g. How to handle glyph ranges, how to merge icons fonts).
+  Command line tool "binary_to_compressed_c" to create compressed arrays to embed data in source code.
+  Suggested fonts and links.
+
+misc/freetype/
+  Font atlas builder/rasterizer using FreeType instead of stb_truetype.
+  Benefit from better FreeType rasterization, in particular for small fonts.
+
+misc/natvis/
+  Natvis file to describe dear imgui types in the Visual Studio debugger.
+  With this, types like ImVector<> will be displayed nicely in the debugger.
+  You can include this file a Visual Studio project file, or install it in Visual Studio folder.
+
+misc/single_file/
+  Single-file header stub.
+  We use this to validate compiling all *.cpp files in a same compilation unit.
+  Users of that technique (also called "Unity builds") can generally provide this themselves,
+  so we don't really recommend you use this in your projects.

include/imgui/misc/cpp/README.txt

+
+imgui_stdlib.h + imgui_stdlib.cpp
+  InputText() wrappers for C++ standard library (STL) type: std::string.
+  This is also an example of how you may wrap your own similar types.
+
+imgui_scoped.h
+  [Experimental, not currently in main repository]
+  Additional header file with some RAII-style wrappers for common Dear ImGui functions.
+  Try by merging: https://github.com/ocornut/imgui/pull/2197
+  Discuss at: https://github.com/ocornut/imgui/issues/2096

include/imgui/misc/cpp/imgui_stdlib.cpp

+// dear imgui: wrappers for C++ standard library (STL) types (std::string, etc.)
+// This is also an example of how you may wrap your own similar types.
+
+// Compatibility:
+// - std::string support is only guaranteed to work from C++11.
+//   If you try to use it pre-C++11, please share your findings (w/ info about compiler/architecture)
+
+// Changelog:
+// - v0.10: Initial version. Added InputText() / InputTextMultiline() calls with std::string
+
+#include "imgui.h"
+#include "imgui_stdlib.h"
+
+struct InputTextCallback_UserData
+{
+    std::string*            Str;
+    ImGuiInputTextCallback  ChainCallback;
+    void*                   ChainCallbackUserData;
+};
+
+static int InputTextCallback(ImGuiInputTextCallbackData* data)
+{
+    InputTextCallback_UserData* user_data = (InputTextCallback_UserData*)data->UserData;
+    if (data->EventFlag == ImGuiInputTextFlags_CallbackResize)
+    {
+        // Resize string callback
+        // If for some reason we refuse the new length (BufTextLen) and/or capacity (BufSize) we need to set them back to what we want.
+        std::string* str = user_data->Str;
+        IM_ASSERT(data->Buf == str->c_str());
+        str->resize(data->BufTextLen);
+        data->Buf = (char*)str->c_str();
+    }
+    else if (user_data->ChainCallback)
+    {
+        // Forward to user callback, if any
+        data->UserData = user_data->ChainCallbackUserData;
+        return user_data->ChainCallback(data);
+    }
+    return 0;
+}
+
+bool ImGui::InputText(const char* label, std::string* str, ImGuiInputTextFlags flags, ImGuiInputTextCallback callback, void* user_data)
+{
+    IM_ASSERT((flags & ImGuiInputTextFlags_CallbackResize) == 0);
+    flags |= ImGuiInputTextFlags_CallbackResize;
+
+    InputTextCallback_UserData cb_user_data;
+    cb_user_data.Str = str;
+    cb_user_data.ChainCallback = callback;
+    cb_user_data.ChainCallbackUserData = user_data;
+    return InputText(label, (char*)str->c_str(), str->capacity() + 1, flags, InputTextCallback, &cb_user_data);
+}
+
+bool ImGui::InputTextMultiline(const char* label, std::string* str, const ImVec2& size, ImGuiInputTextFlags flags, ImGuiInputTextCallback callback, void* user_data)
+{
+    IM_ASSERT((flags & ImGuiInputTextFlags_CallbackResize) == 0);
+    flags |= ImGuiInputTextFlags_CallbackResize;
+
+    InputTextCallback_UserData cb_user_data;
+    cb_user_data.Str = str;
+    cb_user_data.ChainCallback = callback;
+    cb_user_data.ChainCallbackUserData = user_data;
+    return InputTextMultiline(label, (char*)str->c_str(), str->capacity() + 1, size, flags, InputTextCallback, &cb_user_data);
+}
+
+bool ImGui::InputTextWithHint(const char* label, const char* hint, std::string* str, ImGuiInputTextFlags flags, ImGuiInputTextCallback callback, void* user_data)
+{
+    IM_ASSERT((flags & ImGuiInputTextFlags_CallbackResize) == 0);
+    flags |= ImGuiInputTextFlags_CallbackResize;
+
+    InputTextCallback_UserData cb_user_data;
+    cb_user_data.Str = str;
+    cb_user_data.ChainCallback = callback;
+    cb_user_data.ChainCallbackUserData = user_data;
+    return InputTextWithHint(label, hint, (char*)str->c_str(), str->capacity() + 1, flags, InputTextCallback, &cb_user_data);
+}

include/imgui/misc/cpp/imgui_stdlib.h

+// dear imgui: wrappers for C++ standard library (STL) types (std::string, etc.)
+// This is also an example of how you may wrap your own similar types.
+
+// Compatibility:
+// - std::string support is only guaranteed to work from C++11.
+//   If you try to use it pre-C++11, please share your findings (w/ info about compiler/architecture)
+
+// Changelog:
+// - v0.10: Initial version. Added InputText() / InputTextMultiline() calls with std::string
+
+#pragma once
+
+#include <string>
+
+namespace ImGui
+{
+    // ImGui::InputText() with std::string
+    // Because text input needs dynamic resizing, we need to setup a callback to grow the capacity
+    IMGUI_API bool  InputText(const char* label, std::string* str, ImGuiInputTextFlags flags = 0, ImGuiInputTextCallback callback = NULL, void* user_data = NULL);
+    IMGUI_API bool  InputTextMultiline(const char* label, std::string* str, const ImVec2& size = ImVec2(0, 0), ImGuiInputTextFlags flags = 0, ImGuiInputTextCallback callback = NULL, void* user_data = NULL);
+    IMGUI_API bool  InputTextWithHint(const char* label, const char* hint, std::string* str, ImGuiInputTextFlags flags = 0, ImGuiInputTextCallback callback = NULL, void* user_data = NULL);
+}