minor tweaks

.gitignore

@@ -9,6 +9,7 @@
 *.user
 *.userosscache
 *.sln.docstates
+*.json
 
 # User-specific files (MonoDevelop/Xamarin Studio)
 *.userprefs
@@ -32,6 +33,7 @@ bld/
 [Oo]ut/
 [Ll]og/
 [Ll]ogs/
+[Bb]uild/
 
 # Visual Studio 2015/2017 cache/options directory
 .vs/

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "vendor/SDL"]
+	path = vendor/SDL
+	url = https://github.com/libsdl-org/SDL

CMakeLists.txt

@@ -8,15 +8,9 @@ set(CMAKE_CXX_STANDARD 17)
 
 add_compile_definitions(_CRT_SECURE_NO_WARNINGS)
 
-find_package(SDL2 CONFIG REQUIRED)
-find_package(glad CONFIG REQUIRED)
-find_package(imgui CONFIG REQUIRED)
-
-file(GLOB_RECURSE HEADER_FILES 
-	"include/*.hpp"
-)
+add_subdirectory("vendor/SDL")
 
 # Add source to this project's executable.
-add_subdirectory(src)
+add_subdirectory("src")
 
 # TODO: Add tests and install targets if needed.

CMakeSettings.json

@@ -1,29 +0,0 @@
-{
-  "configurations": [
-    {
-      "name": "x64-Debug",
-      "generator": "Ninja",
-      "configurationType": "Debug",
-      "inheritEnvironments": [ "clang_cl_x64" ],
-      "buildRoot": "${projectDir}\\out\\build\\${name}",
-      "installRoot": "${projectDir}\\out\\install\\${name}",
-      "cmakeCommandArgs": "",
-      "buildCommandArgs": "",
-      "ctestCommandArgs": "",
-      "cmakeToolchain": "C:/Users/Robert/source/repos/vcpkg/scripts/buildsystems/vcpkg.cmake"
-    },
-    {
-      "name": "x64-Clang-Release",
-      "generator": "Ninja",
-      "configurationType": "RelWithDebInfo",
-      "buildRoot": "${projectDir}\\out\\build\\${name}",
-      "installRoot": "${projectDir}\\out\\install\\${name}",
-      "cmakeCommandArgs": "",
-      "buildCommandArgs": "",
-      "ctestCommandArgs": "",
-      "cmakeToolchain": "C:/Users/Robert/source/repos/vcpkg/scripts/buildsystems/vcpkg.cmake",
-      "inheritEnvironments": [ "clang_cl_x64_x64" ],
-      "variables": []
-    }
-  ]
-}

src/CMakeLists.txt

@@ -1,26 +1,24 @@
-file(GLOB_RECURSE IMGUI_SRC
-	"${CMAKE_SOURCE_DIR}/vendor/imgui/src/*.cpp"
-)
+add_executable(yabgbe "main.cpp" "bus.cpp" "cpu.cpp" "rom.cpp" "lcd.cpp")
 
-add_executable(yabgbe)
-target_sources(yabgbe 
-	PRIVATE 
-		"main.cpp" "bus.cpp" "cpu.cpp" "rom.cpp" "lcd.cpp" 
-		${IMGUI_SRC}
-	PUBLIC 
-		${HEADER_FILES}
+file(GLOB_RECURSE OTHER_SOURCES
+	"${CMAKE_SOURCE_DIR}/vendor/imgui/*.cpp"
+	"${CMAKE_SOURCE_DIR}/vendor/glad/*.c"
 )
+target_sources(yabgbe PUBLIC ${OTHER_SOURCES})
 
 target_include_directories(yabgbe 
 	PUBLIC 
-		"${CMAKE_SOURCE_DIR}/include"
 		"${CMAKE_SOURCE_DIR}/vendor/imgui/include"
-		SDL2::SDL2 glad::glad
+		"${CMAKE_SOURCE_DIR}/vendor/glad/include"
+		SDL2
 )
 
 target_link_libraries(yabgbe 
-	SDL2::SDL2 SDL2::SDL2main
-	glad::glad
+	SDL2
 )
 
-target_compile_options(yabgbe PRIVATE -Wimplicit-fallthrough)
+if(WIN32)
+	add_custom_command(TARGET yabgbe POST_BUILD 
+		COMMAND ${CMAKE_COMMAND} -E copy $<TARGET_FILE:SDL2> $<TARGET_FILE_DIR:yabgbe>
+	)
+endif()

src/main.cpp

@@ -8,6 +8,8 @@
 
 static BYTE colormap[4] = { 0b00000000, 0b00100101, 0b01001010, 0b10010011 };
 
+#undef main
+
 int main(int argc, char** argv)
 {
 	// Calculate the size of the window? This is literally random lol

vendor/SDL

@@ -0,0 +1 @@
+Subproject commit ac54d57aa524ce2a2d392c7b794cdab31ca3e81f

vendor/glad/include/KHR/khrplatform.h

@@ -0,0 +1,290 @@
+#ifndef __khrplatform_h_
+#define __khrplatform_h_
+
+/*
+** Copyright (c) 2008-2018 The Khronos Group Inc.
+**
+** Permission is hereby granted, free of charge, to any person obtaining a
+** copy of this software and/or associated documentation files (the
+** "Materials"), to deal in the Materials without restriction, including
+** without limitation the rights to use, copy, modify, merge, publish,
+** distribute, sublicense, and/or sell copies of the Materials, and to
+** permit persons to whom the Materials are 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 Materials.
+**
+** THE MATERIALS ARE 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
+** MATERIALS OR THE USE OR OTHER DEALINGS IN THE MATERIALS.
+*/
+
+/* Khronos platform-specific types and definitions.
+ *
+ * The master copy of khrplatform.h is maintained in the Khronos EGL
+ * Registry repository at https://github.com/KhronosGroup/EGL-Registry
+ * The last semantic modification to khrplatform.h was at commit ID:
+ *      67a3e0864c2d75ea5287b9f3d2eb74a745936692
+ *
+ * Adopters may modify this file to suit their platform. Adopters are
+ * encouraged to submit platform specific modifications to the Khronos
+ * group so that they can be included in future versions of this file.
+ * Please submit changes by filing pull requests or issues on
+ * the EGL Registry repository linked above.
+ *
+ *
+ * See the Implementer's Guidelines for information about where this file
+ * should be located on your system and for more details of its use:
+ *    http://www.khronos.org/registry/implementers_guide.pdf
+ *
+ * This file should be included as
+ *        #include <KHR/khrplatform.h>
+ * by Khronos client API header files that use its types and defines.
+ *
+ * The types in khrplatform.h should only be used to define API-specific types.
+ *
+ * Types defined in khrplatform.h:
+ *    khronos_int8_t              signed   8  bit
+ *    khronos_uint8_t             unsigned 8  bit
+ *    khronos_int16_t             signed   16 bit
+ *    khronos_uint16_t            unsigned 16 bit
+ *    khronos_int32_t             signed   32 bit
+ *    khronos_uint32_t            unsigned 32 bit
+ *    khronos_int64_t             signed   64 bit
+ *    khronos_uint64_t            unsigned 64 bit
+ *    khronos_intptr_t            signed   same number of bits as a pointer
+ *    khronos_uintptr_t           unsigned same number of bits as a pointer
+ *    khronos_ssize_t             signed   size
+ *    khronos_usize_t             unsigned size
+ *    khronos_float_t             signed   32 bit floating point
+ *    khronos_time_ns_t           unsigned 64 bit time in nanoseconds
+ *    khronos_utime_nanoseconds_t unsigned time interval or absolute time in
+ *                                         nanoseconds
+ *    khronos_stime_nanoseconds_t signed time interval in nanoseconds
+ *    khronos_boolean_enum_t      enumerated boolean type. This should
+ *      only be used as a base type when a client API's boolean type is
+ *      an enum. Client APIs which use an integer or other type for
+ *      booleans cannot use this as the base type for their boolean.
+ *
+ * Tokens defined in khrplatform.h:
+ *
+ *    KHRONOS_FALSE, KHRONOS_TRUE Enumerated boolean false/true values.
+ *
+ *    KHRONOS_SUPPORT_INT64 is 1 if 64 bit integers are supported; otherwise 0.
+ *    KHRONOS_SUPPORT_FLOAT is 1 if floats are supported; otherwise 0.
+ *
+ * Calling convention macros defined in this file:
+ *    KHRONOS_APICALL
+ *    KHRONOS_APIENTRY
+ *    KHRONOS_APIATTRIBUTES
+ *
+ * These may be used in function prototypes as:
+ *
+ *      KHRONOS_APICALL void KHRONOS_APIENTRY funcname(
+ *                                  int arg1,
+ *                                  int arg2) KHRONOS_APIATTRIBUTES;
+ */
+
+#if defined(__SCITECH_SNAP__) && !defined(KHRONOS_STATIC)
+#   define KHRONOS_STATIC 1
+#endif
+
+/*-------------------------------------------------------------------------
+ * Definition of KHRONOS_APICALL
+ *-------------------------------------------------------------------------
+ * This precedes the return type of the function in the function prototype.
+ */
+#if defined(KHRONOS_STATIC)
+    /* If the preprocessor constant KHRONOS_STATIC is defined, make the
+     * header compatible with static linking. */
+#   define KHRONOS_APICALL
+#elif defined(_WIN32)
+#   define KHRONOS_APICALL __declspec(dllimport)
+#elif defined (__SYMBIAN32__)
+#   define KHRONOS_APICALL IMPORT_C
+#elif defined(__ANDROID__)
+#   define KHRONOS_APICALL __attribute__((visibility("default")))
+#else
+#   define KHRONOS_APICALL
+#endif
+
+/*-------------------------------------------------------------------------
+ * Definition of KHRONOS_APIENTRY
+ *-------------------------------------------------------------------------
+ * This follows the return type of the function  and precedes the function
+ * name in the function prototype.
+ */
+#if defined(_WIN32) && !defined(_WIN32_WCE) && !defined(__SCITECH_SNAP__)
+    /* Win32 but not WinCE */
+#   define KHRONOS_APIENTRY __stdcall
+#else
+#   define KHRONOS_APIENTRY
+#endif
+
+/*-------------------------------------------------------------------------
+ * Definition of KHRONOS_APIATTRIBUTES
+ *-------------------------------------------------------------------------
+ * This follows the closing parenthesis of the function prototype arguments.
+ */
+#if defined (__ARMCC_2__)
+#define KHRONOS_APIATTRIBUTES __softfp
+#else
+#define KHRONOS_APIATTRIBUTES
+#endif
+
+/*-------------------------------------------------------------------------
+ * basic type definitions
+ *-----------------------------------------------------------------------*/
+#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || defined(__GNUC__) || defined(__SCO__) || defined(__USLC__)
+
+
+/*
+ * Using <stdint.h>
+ */
+#include <stdint.h>
+typedef int32_t                 khronos_int32_t;
+typedef uint32_t                khronos_uint32_t;
+typedef int64_t                 khronos_int64_t;
+typedef uint64_t                khronos_uint64_t;
+#define KHRONOS_SUPPORT_INT64   1
+#define KHRONOS_SUPPORT_FLOAT   1
+
+#elif defined(__VMS ) || defined(__sgi)
+
+/*
+ * Using <inttypes.h>
+ */
+#include <inttypes.h>
+typedef int32_t                 khronos_int32_t;
+typedef uint32_t                khronos_uint32_t;
+typedef int64_t                 khronos_int64_t;
+typedef uint64_t                khronos_uint64_t;
+#define KHRONOS_SUPPORT_INT64   1
+#define KHRONOS_SUPPORT_FLOAT   1
+
+#elif defined(_WIN32) && !defined(__SCITECH_SNAP__)
+
+/*
+ * Win32
+ */
+typedef __int32                 khronos_int32_t;
+typedef unsigned __int32        khronos_uint32_t;
+typedef __int64                 khronos_int64_t;
+typedef unsigned __int64        khronos_uint64_t;
+#define KHRONOS_SUPPORT_INT64   1
+#define KHRONOS_SUPPORT_FLOAT   1
+
+#elif defined(__sun__) || defined(__digital__)
+
+/*
+ * Sun or Digital
+ */
+typedef int                     khronos_int32_t;
+typedef unsigned int            khronos_uint32_t;
+#if defined(__arch64__) || defined(_LP64)
+typedef long int                khronos_int64_t;
+typedef unsigned long int       khronos_uint64_t;
+#else
+typedef long long int           khronos_int64_t;
+typedef unsigned long long int  khronos_uint64_t;
+#endif /* __arch64__ */
+#define KHRONOS_SUPPORT_INT64   1
+#define KHRONOS_SUPPORT_FLOAT   1
+
+#elif 0
+
+/*
+ * Hypothetical platform with no float or int64 support
+ */
+typedef int                     khronos_int32_t;
+typedef unsigned int            khronos_uint32_t;
+#define KHRONOS_SUPPORT_INT64   0
+#define KHRONOS_SUPPORT_FLOAT   0
+
+#else
+
+/*
+ * Generic fallback
+ */
+#include <stdint.h>
+typedef int32_t                 khronos_int32_t;
+typedef uint32_t                khronos_uint32_t;
+typedef int64_t                 khronos_int64_t;
+typedef uint64_t                khronos_uint64_t;
+#define KHRONOS_SUPPORT_INT64   1
+#define KHRONOS_SUPPORT_FLOAT   1
+
+#endif
+
+
+/*
+ * Types that are (so far) the same on all platforms
+ */
+typedef signed   char          khronos_int8_t;
+typedef unsigned char          khronos_uint8_t;
+typedef signed   short int     khronos_int16_t;
+typedef unsigned short int     khronos_uint16_t;
+
+/*
+ * Types that differ between LLP64 and LP64 architectures - in LLP64,
+ * pointers are 64 bits, but 'long' is still 32 bits. Win64 appears
+ * to be the only LLP64 architecture in current use.
+ */
+#ifdef _WIN64
+typedef signed   long long int khronos_intptr_t;
+typedef unsigned long long int khronos_uintptr_t;
+typedef signed   long long int khronos_ssize_t;
+typedef unsigned long long int khronos_usize_t;
+#else
+typedef signed   long  int     khronos_intptr_t;
+typedef unsigned long  int     khronos_uintptr_t;
+typedef signed   long  int     khronos_ssize_t;
+typedef unsigned long  int     khronos_usize_t;
+#endif
+
+#if KHRONOS_SUPPORT_FLOAT
+/*
+ * Float type
+ */
+typedef          float         khronos_float_t;
+#endif
+
+#if KHRONOS_SUPPORT_INT64
+/* Time types
+ *
+ * These types can be used to represent a time interval in nanoseconds or
+ * an absolute Unadjusted System Time.  Unadjusted System Time is the number
+ * of nanoseconds since some arbitrary system event (e.g. since the last
+ * time the system booted).  The Unadjusted System Time is an unsigned
+ * 64 bit value that wraps back to 0 every 584 years.  Time intervals
+ * may be either signed or unsigned.
+ */
+typedef khronos_uint64_t       khronos_utime_nanoseconds_t;
+typedef khronos_int64_t        khronos_stime_nanoseconds_t;
+#endif
+
+/*
+ * Dummy value used to pad enum types to 32 bits.
+ */
+#ifndef KHRONOS_MAX_ENUM
+#define KHRONOS_MAX_ENUM 0x7FFFFFFF
+#endif
+
+/*
+ * Enumerated boolean type
+ *
+ * Values other than zero should be considered to be true.  Therefore
+ * comparisons should not be made against KHRONOS_TRUE.
+ */
+typedef enum {
+    KHRONOS_FALSE = 0,
+    KHRONOS_TRUE  = 1,
+    KHRONOS_BOOLEAN_ENUM_FORCE_SIZE = KHRONOS_MAX_ENUM
+} khronos_boolean_enum_t;
+
+#endif /* __khrplatform_h_ */

vendor/imgui/include/imconfig.h

@@ -0,0 +1,102 @@
+// B) or '#define IMGUI_USER_CONFIG "my_imgui_config.h"' in your project and then add directives in your own file without touching this template.
+//-----------------------------------------------------------------------------
+// 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);
+}
+*/

vendor/imgui/include/imstb_rectpack.h

@@ -0,0 +1,644 @@
+// [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.
+------------------------------------------------------------------------------
+*/