Update dear-imgui to v1.91.9b (#21)

* Update dear-imgui to v1.91.9b

This change bumps dear-imgui to the latest version.

* Restore IMGUI_DPF_BACKEND pragma

Author: TristanCacqueray

opengl/DearImGui/imconfig.h

@@ -1,5 +1,5 @@
 //-----------------------------------------------------------------------------
-// COMPILE-TIME OPTIONS FOR DEAR IMGUI
+// DEAR IMGUI COMPILE-TIME OPTIONS
 // 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.
 //-----------------------------------------------------------------------------
@@ -9,7 +9,7 @@
 // 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.
+// Call IMGUI_CHECKVERSION() from your .cpp file to verify that the data structures your files are using are matching the ones imgui.cpp is using.
 //-----------------------------------------------------------------------------
 
 #pragma once
@@ -21,50 +21,61 @@
 
 //---- 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.
-// DLL users: heaps and globals are not shared across DLL boundaries! You will need to call SetCurrentContext() + SetAllocatorFunctions()
-// for each static/DLL boundary you are calling from. Read "Context and Memory Allocators" section of imgui.cpp for more details.
-//#define IMGUI_API __declspec( dllexport )
-//#define IMGUI_API __declspec( dllimport )
+// - Windows DLL users: heaps and globals are not shared across DLL boundaries! You will need to call SetCurrentContext() + SetAllocatorFunctions()
+//   for each static/DLL boundary you are calling from. Read "Context and Memory Allocators" section of imgui.cpp for more details.
+//#define IMGUI_API __declspec(dllexport)                   // MSVC Windows: DLL export
+//#define IMGUI_API __declspec(dllimport)                   // MSVC Windows: DLL import
+//#define IMGUI_API __attribute__((visibility("default")))  // GCC/Clang: override visibility when set is hidden
 
-//---- 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
-#define IMGUI_DISABLE_OBSOLETE_KEYIO                      // 1.87: disable legacy io.KeyMap[]+io.KeysDown[] in favor io.AddKeyEvent(). This will be folded into IMGUI_DISABLE_OBSOLETE_FUNCTIONS in a few versions.
+//---- Don't define obsolete functions/enums/behaviors. Consider enabling from time to time after updating to clean your code of obsolete function/names.
+//#define IMGUI_DISABLE_OBSOLETE_FUNCTIONS
 
 //---- Disable all of Dear ImGui or don't implement standard windows/tools.
 // It is very strongly recommended to NOT disable the demo windows and debug tool during development. They are extremely useful in day to day work. 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.
-//#define IMGUI_DISABLE_DEBUG_TOOLS                         // Disable metrics/debugger and other debug tools: ShowMetricsWindow(), ShowDebugLogWindow() and ShowStackToolWindow() will be empty (this was called IMGUI_DISABLE_METRICS_WINDOW before 1.88).
+//#define IMGUI_DISABLE_DEBUG_TOOLS                         // Disable metrics/debugger and other debug tools: ShowMetricsWindow(), ShowDebugLogWindow() and ShowIDStackToolWindow() 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. (user32.lib/.a, kernel32.lib/.a)
 //#define IMGUI_ENABLE_WIN32_DEFAULT_IME_FUNCTIONS          // [Win32] [Default with Visual Studio] Implement default IME handler (require imm32.lib/.a, auto-link for Visual Studio, -limm32 on command-line for MinGW)
 //#define IMGUI_DISABLE_WIN32_DEFAULT_IME_FUNCTIONS         // [Win32] [Default with non-Visual Studio compilers] Don't implement default IME handler (won't require imm32.lib/.a)
-//#define IMGUI_DISABLE_WIN32_FUNCTIONS                     // [Win32] Won't use and link with any Win32 function (clipboard, ime).
+//#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_SHELL_FUNCTIONS             // Don't implement default platform_io.Platform_OpenInShellFn() handler (Win32: ShellExecute(), require shell32.lib/.a, Mac/Linux: use system("")).
 //#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_FILE_FUNCTIONS                      // Don't implement ImFileOpen/ImFileClose/ImFileRead/ImFileWrite and ImFileHandle at all (replace them with dummies)
 //#define IMGUI_DISABLE_DEFAULT_FILE_FUNCTIONS              // Don't implement ImFileOpen/ImFileClose/ImFileRead/ImFileWrite and ImFileHandle 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().
+//#define IMGUI_DISABLE_DEFAULT_FONT                        // Disable default embedded font (ProggyClean.ttf), remove ~9.5 KB from output binary. AddFontDefault() will assert.
 //#define IMGUI_DISABLE_SSE                                 // Disable use of SSE intrinsics even if available
 
+//---- Enable Test Engine / Automation features.
+//#define IMGUI_ENABLE_TEST_ENGINE                          // Enable imgui_test_engine hooks. Generally set automatically by include "imgui_te_config.h", see Test Engine for details.
+
 //---- Include imgui_user.h at the end of imgui.h as a convenience
+// May be convenient for some users to only explicitly include vanilla imgui.h and have extra stuff included.
 //#define IMGUI_INCLUDE_IMGUI_USER_H
+//#define IMGUI_USER_H_FILENAME         "my_folder/my_imgui_user.h"
 
-//---- Pack colors to BGRA8 instead of RGBA8 (to avoid converting from one to another)
+//---- Pack vertex colors as BGRA8 instead of RGBA8 (to avoid converting from one to another). Need dedicated backend support.
 //#define IMGUI_USE_BGRA_PACKED_COLOR
 
-//---- Use 32-bit for ImWchar (default is 16-bit) to support unicode planes 1-16. (e.g. point beyond 0xFFFF like emoticons, dingbats, symbols, shapes, ancient languages, etc...)
+//---- Use legacy CRC32-adler tables (used before 1.91.6), in order to preserve old .ini data that you cannot afford to invalidate.
+//#define IMGUI_USE_LEGACY_CRC32_ADLER
+
+//---- Use 32-bit for ImWchar (default is 16-bit) to support Unicode planes 1-16. (e.g. point beyond 0xFFFF like emoticons, dingbats, symbols, shapes, ancient languages, etc...)
 //#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 Dear ImGui sources 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_STB_SPRINTF_FILENAME    "my_folder/stb_sprintf.h"    // only used if enabled
+//#define IMGUI_STB_SPRINTF_FILENAME    "my_folder/stb_sprintf.h"    // only used if IMGUI_USE_STB_SPRINTF is defined.
 //#define IMGUI_DISABLE_STB_TRUETYPE_IMPLEMENTATION
 //#define IMGUI_DISABLE_STB_RECT_PACK_IMPLEMENTATION
+//#define IMGUI_DISABLE_STB_SPRINTF_IMPLEMENTATION                   // only disabled if IMGUI_USE_STB_SPRINTF is defined.
 
 //---- Use stb_sprintf.h for a faster implementation of vsnprintf instead of the one from libc (unless IMGUI_DISABLE_DEFAULT_FORMAT_FUNCTIONS is defined)
 // Compatibility checks of arguments and formats done by clang and GCC will be disabled in order to support the extra formats provided by stb_sprintf.h.
@@ -75,6 +86,14 @@
 // On Windows you may use vcpkg with 'vcpkg install freetype --triplet=x64-windows' + 'vcpkg integrate install'.
 //#define IMGUI_ENABLE_FREETYPE
 
+//---- Use FreeType + plutosvg or lunasvg to render OpenType SVG fonts (SVGinOT)
+// Only works in combination with IMGUI_ENABLE_FREETYPE.
+// - plutosvg is currently easier to install, as e.g. it is part of vcpkg. It will support more fonts and may load them faster. See misc/freetype/README for instructions.
+// - Both require headers to be available in the include path + program to be linked with the library code (not provided).
+// - (note: lunasvg implementation is based on Freetype's rsvg-port.c which is licensed under CeCILL-C Free Software License Agreement)
+//#define IMGUI_ENABLE_FREETYPE_PLUTOSVG
+//#define IMGUI_ENABLE_FREETYPE_LUNASVG
+
 //---- Use stb_truetype to build and rasterize the font atlas (default)
 // The only purpose of this define is if you want force compilation of the stb_truetype backend ALONG with the FreeType backend.
 //#define IMGUI_ENABLE_STB_TRUETYPE
@@ -105,18 +124,18 @@
 //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
+//---- Debug Tools: Macro to break in Debugger (we provide a default implementation of this in the codebase)
 // (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: Enable slower asserts
 //#define IMGUI_DEBUG_PARANOID
 
-//---- Tip: You can add extra functions within the ImGui:: namespace, here or in your own headers files.
+//---- Tip: You can add extra functions within the ImGui:: namespace from anywhere (e.g. your own sources/header files)
 /*
 namespace ImGui
 {
-    void MyFunction(const char* name, const MyMatrix44& v);
+    void MyFunction(const char* name, MyMatrix44* mtx);
 }
 */