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Diffstat (limited to 'dependencies/src/imgui/imgui_impl_opengl3.cpp')
| -rw-r--r-- | dependencies/src/imgui/imgui_impl_opengl3.cpp | 910 |
1 files changed, 910 insertions, 0 deletions
diff --git a/dependencies/src/imgui/imgui_impl_opengl3.cpp b/dependencies/src/imgui/imgui_impl_opengl3.cpp new file mode 100644 index 0000000..b7587d0 --- /dev/null +++ b/dependencies/src/imgui/imgui_impl_opengl3.cpp @@ -0,0 +1,910 @@ +// dear imgui: Renderer Backend 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 Backend (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: Multi-viewport support (multiple windows). Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'. +// [x] Renderer: Large meshes support (64k+ vertices) with 16-bit indices (Desktop OpenGL only). + +// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this. +// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need. +// If you are new to Dear ImGui, read documentation from the docs/ folder + read the top of imgui.cpp. +// Read online: https://github.com/ocornut/imgui/tree/master/docs + +// CHANGELOG +// (minor and older changes stripped away, please see git history for details) +// 2022-XX-XX: Platform: Added support for multiple windows via the ImGuiPlatformIO interface. +// 2022-05-23: OpenGL: Reworking 2021-12-15 "Using buffer orphaning" so it only happens on Intel GPU, seems to cause problems otherwise. (#4468, #4825, #4832, #5127). +// 2022-05-13: OpenGL: Fix state corruption on OpenGL ES 2.0 due to not preserving GL_ELEMENT_ARRAY_BUFFER_BINDING and vertex attribute states. +// 2021-12-15: OpenGL: Using buffer orphaning + glBufferSubData(), seems to fix leaks with multi-viewports with some Intel HD drivers. +// 2021-08-23: OpenGL: Fixed ES 3.0 shader ("#version 300 es") use normal precision floats to avoid wobbly rendering at HD resolutions. +// 2021-08-19: OpenGL: Embed and use our own minimal GL loader (imgui_impl_opengl3_loader.h), removing requirement and support for third-party loader. +// 2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX). +// 2021-06-25: OpenGL: Use OES_vertex_array extension on Emscripten + backup/restore current state. +// 2021-06-21: OpenGL: Destroy individual vertex/fragment shader objects right after they are linked into the main shader. +// 2021-05-24: OpenGL: Access GL_CLIP_ORIGIN when "GL_ARB_clip_control" extension is detected, inside of just OpenGL 4.5 version. +// 2021-05-19: OpenGL: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement) +// 2021-04-06: OpenGL: Don't try to read GL_CLIP_ORIGIN unless we're OpenGL 4.5 or greater. +// 2021-02-18: OpenGL: Change blending equation to preserve alpha in output buffer. +// 2021-01-03: OpenGL: Backup, setup and restore GL_STENCIL_TEST state. +// 2020-10-23: OpenGL: Backup, setup and restore GL_PRIMITIVE_RESTART state. +// 2020-10-15: OpenGL: Use glGetString(GL_VERSION) instead of glGetIntegerv(GL_MAJOR_VERSION, ...) when the later returns zero (e.g. Desktop GL 2.x) +// 2020-09-17: OpenGL: Fix to avoid compiling/calling glBindSampler() on ES or pre 3.3 context which have the defines set by a loader. +// 2020-07-10: OpenGL: Added support for glad2 OpenGL loader. +// 2020-05-08: OpenGL: Made default GLSL version 150 (instead of 130) on OSX. +// 2020-04-21: OpenGL: Fixed handling of glClipControl(GL_UPPER_LEFT) by inverting projection matrix. +// 2020-04-12: OpenGL: Fixed context version check mistakenly testing for 4.0+ instead of 3.2+ to enable ImGuiBackendFlags_RendererHasVtxOffset. +// 2020-03-24: OpenGL: Added support for glbinding 2.x OpenGL loader. +// 2020-01-07: OpenGL: Added support for glbinding 3.x OpenGL loader. +// 2019-10-25: OpenGL: Using a combination of GL define and runtime GL version to decide whether to use glDrawElementsBaseVertex(). Fix building with pre-3.2 GL loaders. +// 2019-09-22: OpenGL: Detect default GL loader using __has_include compiler facility. +// 2019-09-16: OpenGL: Tweak initialization code to allow application calling ImGui_ImplOpenGL3_CreateFontsTexture() before the first NewFrame() call. +// 2019-05-29: OpenGL: Desktop GL only: Added support for large mesh (64K+ vertices), enable ImGuiBackendFlags_RendererHasVtxOffset flag. +// 2019-04-30: OpenGL: Added support for special ImDrawCallback_ResetRenderState callback to reset render state. +// 2019-03-29: OpenGL: Not calling glBindBuffer more than necessary in the render loop. +// 2019-03-15: OpenGL: Added a GL call + comments in ImGui_ImplOpenGL3_Init() to detect uninitialized GL function loaders early. +// 2019-03-03: OpenGL: Fix support for ES 2.0 (WebGL 1.0). +// 2019-02-20: OpenGL: Fix for OSX not supporting OpenGL 4.5, we don't try to read GL_CLIP_ORIGIN even if defined by the headers/loader. +// 2019-02-11: OpenGL: Projecting clipping rectangles correctly using draw_data->FramebufferScale to allow multi-viewports for retina display. +// 2019-02-01: OpenGL: Using GLSL 410 shaders for any version over 410 (e.g. 430, 450). +// 2018-11-30: Misc: Setting up io.BackendRendererName so it can be displayed in the About Window. +// 2018-11-13: OpenGL: Support for GL 4.5's glClipControl(GL_UPPER_LEFT) / GL_CLIP_ORIGIN. +// 2018-08-29: OpenGL: Added support for more OpenGL loaders: glew and glad, with comments indicative that any loader can be used. +// 2018-08-09: OpenGL: Default to OpenGL ES 3 on iOS and Android. GLSL version default to "#version 300 ES". +// 2018-07-30: OpenGL: Support for GLSL 300 ES and 410 core. Fixes for Emscripten compilation. +// 2018-07-10: OpenGL: Support for more GLSL versions (based on the GLSL version string). Added error output when shaders fail to compile/link. +// 2018-06-08: Misc: Extracted imgui_impl_opengl3.cpp/.h away from the old combined GLFW/SDL+OpenGL3 examples. +// 2018-06-08: OpenGL: Use draw_data->DisplayPos and draw_data->DisplaySize to setup projection matrix and clipping rectangle. +// 2018-05-25: OpenGL: Removed unnecessary backup/restore of GL_ELEMENT_ARRAY_BUFFER_BINDING since this is part of the VAO state. +// 2018-05-14: OpenGL: Making the call to glBindSampler() optional so 3.2 context won't fail if the function is a NULL pointer. +// 2018-03-06: OpenGL: Added const char* glsl_version parameter to ImGui_ImplOpenGL3_Init() so user can override the GLSL version e.g. "#version 150". +// 2018-02-23: OpenGL: Create the VAO in the render function so the setup can more easily be used with multiple shared GL context. +// 2018-02-16: Misc: Obsoleted the io.RenderDrawListsFn callback and exposed ImGui_ImplSdlGL3_RenderDrawData() in the .h file so you can call it yourself. +// 2018-01-07: OpenGL: Changed GLSL shader version from 330 to 150. +// 2017-09-01: OpenGL: Save and restore current bound sampler. Save and restore current polygon mode. +// 2017-05-01: OpenGL: Fixed save and restore of current blend func state. +// 2017-05-01: OpenGL: Fixed save and restore of current GL_ACTIVE_TEXTURE. +// 2016-09-05: OpenGL: Fixed save and restore of current scissor rectangle. +// 2016-07-29: OpenGL: Explicitly setting GL_UNPACK_ROW_LENGTH to reduce issues because SDL changes it. (#752) + +//---------------------------------------- +// OpenGL GLSL GLSL +// version version string +//---------------------------------------- +// 2.0 110 "#version 110" +// 2.1 120 "#version 120" +// 3.0 130 "#version 130" +// 3.1 140 "#version 140" +// 3.2 150 "#version 150" +// 3.3 330 "#version 330 core" +// 4.0 400 "#version 400 core" +// 4.1 410 "#version 410 core" +// 4.2 420 "#version 410 core" +// 4.3 430 "#version 430 core" +// ES 2.0 100 "#version 100" = WebGL 1.0 +// ES 3.0 300 "#version 300 es" = WebGL 2.0 +//---------------------------------------- + +#if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_WARNINGS) +#define _CRT_SECURE_NO_WARNINGS +#endif + +#include "imgui.h" +#include "imgui_impl_opengl3.h" +#include <stdio.h> +#if defined(_MSC_VER) && _MSC_VER <= 1500 // MSVC 2008 or earlier +#include <stddef.h> // intptr_t +#else +#include <stdint.h> // intptr_t +#endif +#if defined(__APPLE__) +#include <TargetConditionals.h> +#endif + +// Clang warnings with -Weverything +#if defined(__clang__) +#pragma clang diagnostic push +#pragma clang diagnostic ignored "-Wold-style-cast" // warning: use of old-style cast +#pragma clang diagnostic ignored "-Wsign-conversion" // warning: implicit conversion changes signedness +#if __has_warning("-Wzero-as-null-pointer-constant") +#pragma clang diagnostic ignored "-Wzero-as-null-pointer-constant" +#endif +#endif + +// GL includes +#if defined(IMGUI_IMPL_OPENGL_ES2) +#if (defined(__APPLE__) && (TARGET_OS_IOS || TARGET_OS_TV)) +#include <OpenGLES/ES2/gl.h> // Use GL ES 2 +#else +#include <GLES2/gl2.h> // Use GL ES 2 +#endif +#if defined(__EMSCRIPTEN__) +#ifndef GL_GLEXT_PROTOTYPES +#define GL_GLEXT_PROTOTYPES +#endif +#include <GLES2/gl2ext.h> +#endif +#elif defined(IMGUI_IMPL_OPENGL_ES3) +#if (defined(__APPLE__) && (TARGET_OS_IOS || TARGET_OS_TV)) +#include <OpenGLES/ES3/gl.h> // Use GL ES 3 +#else +#include <GLES3/gl3.h> // Use GL ES 3 +#endif +#elif !defined(IMGUI_IMPL_OPENGL_LOADER_CUSTOM) +// 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 using our own minimal custom loader based on gl3w. +// In the rest of your app/engine, you can use another loader of your choice (gl3w, glew, glad, glbinding, glext, glLoadGen, etc.). +// If you happen to be developing a new feature for this backend (imgui_impl_opengl3.cpp): +// - You may need to regenerate imgui_impl_opengl3_loader.h to add new symbols. See https://github.com/dearimgui/gl3w_stripped +// - You can temporarily use an unstripped version. See https://github.com/dearimgui/gl3w_stripped/releases +// Changes to this backend using new APIs should be accompanied by a regenerated stripped loader version. +#define IMGL3W_IMPL +#include "imgui_impl_opengl3_loader.h" +#endif + +// Vertex arrays are not supported on ES2/WebGL1 unless Emscripten which uses an extension +#ifndef IMGUI_IMPL_OPENGL_ES2 +#define IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY +#elif defined(__EMSCRIPTEN__) +#define IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY +#define glBindVertexArray glBindVertexArrayOES +#define glGenVertexArrays glGenVertexArraysOES +#define glDeleteVertexArrays glDeleteVertexArraysOES +#define GL_VERTEX_ARRAY_BINDING GL_VERTEX_ARRAY_BINDING_OES +#endif + +// Desktop GL 2.0+ has glPolygonMode() which GL ES and WebGL don't have. +#ifdef GL_POLYGON_MODE +#define IMGUI_IMPL_HAS_POLYGON_MODE +#endif + +// Desktop GL 3.2+ has glDrawElementsBaseVertex() which GL ES and WebGL don't have. +#if !defined(IMGUI_IMPL_OPENGL_ES2) && !defined(IMGUI_IMPL_OPENGL_ES3) && defined(GL_VERSION_3_2) +#define IMGUI_IMPL_OPENGL_MAY_HAVE_VTX_OFFSET +#endif + +// Desktop GL 3.3+ has glBindSampler() +#if !defined(IMGUI_IMPL_OPENGL_ES2) && !defined(IMGUI_IMPL_OPENGL_ES3) && defined(GL_VERSION_3_3) +#define IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_SAMPLER +#endif + +// Desktop GL 3.1+ has GL_PRIMITIVE_RESTART state +#if !defined(IMGUI_IMPL_OPENGL_ES2) && !defined(IMGUI_IMPL_OPENGL_ES3) && defined(GL_VERSION_3_1) +#define IMGUI_IMPL_OPENGL_MAY_HAVE_PRIMITIVE_RESTART +#endif + +// Desktop GL use extension detection +#if !defined(IMGUI_IMPL_OPENGL_ES2) && !defined(IMGUI_IMPL_OPENGL_ES3) +#define IMGUI_IMPL_OPENGL_MAY_HAVE_EXTENSIONS +#endif + +// OpenGL Data +struct ImGui_ImplOpenGL3_Data +{ + GLuint GlVersion; // Extracted at runtime using GL_MAJOR_VERSION, GL_MINOR_VERSION queries (e.g. 320 for GL 3.2) + char GlslVersionString[32]; // Specified by user or detected based on compile time GL settings. + GLuint FontTexture; + GLuint ShaderHandle; + GLint AttribLocationTex; // Uniforms location + GLint AttribLocationProjMtx; + GLuint AttribLocationVtxPos; // Vertex attributes location + GLuint AttribLocationVtxUV; + GLuint AttribLocationVtxColor; + unsigned int VboHandle, ElementsHandle; + GLsizeiptr VertexBufferSize; + GLsizeiptr IndexBufferSize; + bool HasClipOrigin; + bool UseBufferSubData; + + ImGui_ImplOpenGL3_Data() { memset((void*)this, 0, sizeof(*this)); } +}; + +// Backend data stored in io.BackendRendererUserData to allow support for multiple Dear ImGui contexts +// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts. +static ImGui_ImplOpenGL3_Data* ImGui_ImplOpenGL3_GetBackendData() +{ + return ImGui::GetCurrentContext() ? (ImGui_ImplOpenGL3_Data*)ImGui::GetIO().BackendRendererUserData : NULL; +} + +// Forward Declarations +static void ImGui_ImplOpenGL3_InitPlatformInterface(); +static void ImGui_ImplOpenGL3_ShutdownPlatformInterface(); + +// OpenGL vertex attribute state (for ES 1.0 and ES 2.0 only) +#ifndef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY +struct ImGui_ImplOpenGL3_VtxAttribState +{ + GLint Enabled, Size, Type, Normalized, Stride; + GLvoid* Ptr; + + void GetState(GLint index) + { + glGetVertexAttribiv(index, GL_VERTEX_ATTRIB_ARRAY_ENABLED, &Enabled); + glGetVertexAttribiv(index, GL_VERTEX_ATTRIB_ARRAY_SIZE, &Size); + glGetVertexAttribiv(index, GL_VERTEX_ATTRIB_ARRAY_TYPE, &Type); + glGetVertexAttribiv(index, GL_VERTEX_ATTRIB_ARRAY_NORMALIZED, &Normalized); + glGetVertexAttribiv(index, GL_VERTEX_ATTRIB_ARRAY_STRIDE, &Stride); + glGetVertexAttribPointerv(index, GL_VERTEX_ATTRIB_ARRAY_POINTER, &Ptr); + } + void SetState(GLint index) + { + glVertexAttribPointer(index, Size, Type, (GLboolean)Normalized, Stride, Ptr); + if (Enabled) glEnableVertexAttribArray(index); else glDisableVertexAttribArray(index); + } +}; +#endif + +// Functions +bool ImGui_ImplOpenGL3_Init(const char* glsl_version) +{ + ImGuiIO& io = ImGui::GetIO(); + IM_ASSERT(io.BackendRendererUserData == NULL && "Already initialized a renderer backend!"); + + // Initialize our loader +#if !defined(IMGUI_IMPL_OPENGL_ES2) && !defined(IMGUI_IMPL_OPENGL_ES3) && !defined(IMGUI_IMPL_OPENGL_LOADER_CUSTOM) + if (imgl3wInit() != 0) + { + fprintf(stderr, "Failed to initialize OpenGL loader!\n"); + return false; + } +#endif + + // Setup backend capabilities flags + ImGui_ImplOpenGL3_Data* bd = IM_NEW(ImGui_ImplOpenGL3_Data)(); + io.BackendRendererUserData = (void*)bd; + io.BackendRendererName = "imgui_impl_opengl3"; + + // Query for GL version (e.g. 320 for GL 3.2) +#if !defined(IMGUI_IMPL_OPENGL_ES2) + GLint major = 0; + GLint minor = 0; + glGetIntegerv(GL_MAJOR_VERSION, &major); + glGetIntegerv(GL_MINOR_VERSION, &minor); + if (major == 0 && minor == 0) + { + // Query GL_VERSION in desktop GL 2.x, the string will start with "<major>.<minor>" + const char* gl_version = (const char*)glGetString(GL_VERSION); + sscanf(gl_version, "%d.%d", &major, &minor); + } + bd->GlVersion = (GLuint)(major * 100 + minor * 10); + + // Query vendor to enable glBufferSubData kludge +#ifdef _WIN32 + if (const char* vendor = (const char*)glGetString(GL_VENDOR)) + if (strncmp(vendor, "Intel", 5) == 0) + bd->UseBufferSubData = true; +#endif + //printf("GL_MAJOR_VERSION = %d\nGL_MINOR_VERSION = %d\nGL_VENDOR = '%s'\nGL_RENDERER = '%s'\n", major, minor, (const char*)glGetString(GL_VENDOR), (const char*)glGetString(GL_RENDERER)); // [DEBUG] +#else + bd->GlVersion = 200; // GLES 2 +#endif + +#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_VTX_OFFSET + if (bd->GlVersion >= 320) + io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset; // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes. +#endif + io.BackendFlags |= ImGuiBackendFlags_RendererHasViewports; // We can create multi-viewports on the Renderer side (optional) + + // Store GLSL version string so we can refer to it later in case we recreate shaders. + // Note: GLSL version is NOT the same as GL version. Leave this to NULL if unsure. + if (glsl_version == NULL) + { +#if defined(IMGUI_IMPL_OPENGL_ES2) + glsl_version = "#version 100"; +#elif defined(IMGUI_IMPL_OPENGL_ES3) + glsl_version = "#version 300 es"; +#elif defined(__APPLE__) + glsl_version = "#version 150"; +#else + glsl_version = "#version 130"; +#endif + } + IM_ASSERT((int)strlen(glsl_version) + 2 < IM_ARRAYSIZE(bd->GlslVersionString)); + strcpy(bd->GlslVersionString, glsl_version); + strcat(bd->GlslVersionString, "\n"); + + // Make an arbitrary GL call (we don't actually need the result) + // IF YOU GET A CRASH HERE: it probably means the OpenGL function loader didn't do its job. Let us know! + GLint current_texture; + glGetIntegerv(GL_TEXTURE_BINDING_2D, ¤t_texture); + + // Detect extensions we support + bd->HasClipOrigin = (bd->GlVersion >= 450); +#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_EXTENSIONS + GLint num_extensions = 0; + glGetIntegerv(GL_NUM_EXTENSIONS, &num_extensions); + for (GLint i = 0; i < num_extensions; i++) + { + const char* extension = (const char*)glGetStringi(GL_EXTENSIONS, i); + if (extension != NULL && strcmp(extension, "GL_ARB_clip_control") == 0) + bd->HasClipOrigin = true; + } +#endif + + if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable) + ImGui_ImplOpenGL3_InitPlatformInterface(); + + return true; +} + +void ImGui_ImplOpenGL3_Shutdown() +{ + ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData(); + IM_ASSERT(bd != NULL && "No renderer backend to shutdown, or already shutdown?"); + ImGuiIO& io = ImGui::GetIO(); + + ImGui_ImplOpenGL3_ShutdownPlatformInterface(); + ImGui_ImplOpenGL3_DestroyDeviceObjects(); + io.BackendRendererName = NULL; + io.BackendRendererUserData = NULL; + IM_DELETE(bd); +} + +void ImGui_ImplOpenGL3_NewFrame() +{ + ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData(); + IM_ASSERT(bd != NULL && "Did you call ImGui_ImplOpenGL3_Init()?"); + + if (!bd->ShaderHandle) + ImGui_ImplOpenGL3_CreateDeviceObjects(); +} + +static void ImGui_ImplOpenGL3_SetupRenderState(ImDrawData* draw_data, int fb_width, int fb_height, GLuint vertex_array_object) +{ + ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData(); + + // Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled, polygon fill + glEnable(GL_BLEND); + glBlendEquation(GL_FUNC_ADD); + glBlendFuncSeparate(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA, GL_ONE, GL_ONE_MINUS_SRC_ALPHA); + glDisable(GL_CULL_FACE); + glDisable(GL_DEPTH_TEST); + glDisable(GL_STENCIL_TEST); + glEnable(GL_SCISSOR_TEST); +#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_PRIMITIVE_RESTART + if (bd->GlVersion >= 310) + glDisable(GL_PRIMITIVE_RESTART); +#endif +#ifdef IMGUI_IMPL_HAS_POLYGON_MODE + glPolygonMode(GL_FRONT_AND_BACK, GL_FILL); +#endif + + // Support for GL 4.5 rarely used glClipControl(GL_UPPER_LEFT) +#if defined(GL_CLIP_ORIGIN) + bool clip_origin_lower_left = true; + if (bd->HasClipOrigin) + { + GLenum current_clip_origin = 0; glGetIntegerv(GL_CLIP_ORIGIN, (GLint*)¤t_clip_origin); + if (current_clip_origin == GL_UPPER_LEFT) + clip_origin_lower_left = false; + } +#endif + + // Setup viewport, orthographic projection matrix + // Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right). DisplayPos is (0,0) for single viewport apps. + glViewport(0, 0, (GLsizei)fb_width, (GLsizei)fb_height); + float L = draw_data->DisplayPos.x; + float R = draw_data->DisplayPos.x + draw_data->DisplaySize.x; + float T = draw_data->DisplayPos.y; + float B = draw_data->DisplayPos.y + draw_data->DisplaySize.y; +#if defined(GL_CLIP_ORIGIN) + if (!clip_origin_lower_left) { float tmp = T; T = B; B = tmp; } // Swap top and bottom if origin is upper left +#endif + const float ortho_projection[4][4] = + { + { 2.0f/(R-L), 0.0f, 0.0f, 0.0f }, + { 0.0f, 2.0f/(T-B), 0.0f, 0.0f }, + { 0.0f, 0.0f, -1.0f, 0.0f }, + { (R+L)/(L-R), (T+B)/(B-T), 0.0f, 1.0f }, + }; + glUseProgram(bd->ShaderHandle); + glUniform1i(bd->AttribLocationTex, 0); + glUniformMatrix4fv(bd->AttribLocationProjMtx, 1, GL_FALSE, &ortho_projection[0][0]); + +#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_SAMPLER + if (bd->GlVersion >= 330) + glBindSampler(0, 0); // We use combined texture/sampler state. Applications using GL 3.3 may set that otherwise. +#endif + + (void)vertex_array_object; +#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY + glBindVertexArray(vertex_array_object); +#endif + + // Bind vertex/index buffers and setup attributes for ImDrawVert + glBindBuffer(GL_ARRAY_BUFFER, bd->VboHandle); + glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, bd->ElementsHandle); + glEnableVertexAttribArray(bd->AttribLocationVtxPos); + glEnableVertexAttribArray(bd->AttribLocationVtxUV); + glEnableVertexAttribArray(bd->AttribLocationVtxColor); + glVertexAttribPointer(bd->AttribLocationVtxPos, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)IM_OFFSETOF(ImDrawVert, pos)); + glVertexAttribPointer(bd->AttribLocationVtxUV, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)IM_OFFSETOF(ImDrawVert, uv)); + glVertexAttribPointer(bd->AttribLocationVtxColor, 4, GL_UNSIGNED_BYTE, GL_TRUE, sizeof(ImDrawVert), (GLvoid*)IM_OFFSETOF(ImDrawVert, col)); +} + +// OpenGL3 Render function. +// Note that this implementation is little overcomplicated because we are saving/setting up/restoring every OpenGL state explicitly. +// This is in order to be able to run within an OpenGL engine that doesn't do so. +void ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data) +{ + // Avoid rendering when minimized, scale coordinates for retina displays (screen coordinates != framebuffer coordinates) + int fb_width = (int)(draw_data->DisplaySize.x * draw_data->FramebufferScale.x); + int fb_height = (int)(draw_data->DisplaySize.y * draw_data->FramebufferScale.y); + if (fb_width <= 0 || fb_height <= 0) + return; + + ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData(); + + // Backup GL state + GLenum last_active_texture; glGetIntegerv(GL_ACTIVE_TEXTURE, (GLint*)&last_active_texture); + glActiveTexture(GL_TEXTURE0); + GLuint last_program; glGetIntegerv(GL_CURRENT_PROGRAM, (GLint*)&last_program); + GLuint last_texture; glGetIntegerv(GL_TEXTURE_BINDING_2D, (GLint*)&last_texture); +#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_SAMPLER + GLuint last_sampler; if (bd->GlVersion >= 330) { glGetIntegerv(GL_SAMPLER_BINDING, (GLint*)&last_sampler); } else { last_sampler = 0; } +#endif + GLuint last_array_buffer; glGetIntegerv(GL_ARRAY_BUFFER_BINDING, (GLint*)&last_array_buffer); +#ifndef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY + // This is part of VAO on OpenGL 3.0+ and OpenGL ES 3.0+. + GLint last_element_array_buffer; glGetIntegerv(GL_ELEMENT_ARRAY_BUFFER_BINDING, &last_element_array_buffer); + ImGui_ImplOpenGL3_VtxAttribState last_vtx_attrib_state_pos; last_vtx_attrib_state_pos.GetState(bd->AttribLocationVtxPos); + ImGui_ImplOpenGL3_VtxAttribState last_vtx_attrib_state_uv; last_vtx_attrib_state_uv.GetState(bd->AttribLocationVtxUV); + ImGui_ImplOpenGL3_VtxAttribState last_vtx_attrib_state_color; last_vtx_attrib_state_color.GetState(bd->AttribLocationVtxColor); +#endif +#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY + GLuint last_vertex_array_object; glGetIntegerv(GL_VERTEX_ARRAY_BINDING, (GLint*)&last_vertex_array_object); +#endif +#ifdef IMGUI_IMPL_HAS_POLYGON_MODE + GLint last_polygon_mode[2]; glGetIntegerv(GL_POLYGON_MODE, last_polygon_mode); +#endif + GLint last_viewport[4]; glGetIntegerv(GL_VIEWPORT, last_viewport); + GLint last_scissor_box[4]; glGetIntegerv(GL_SCISSOR_BOX, last_scissor_box); + GLenum last_blend_src_rgb; glGetIntegerv(GL_BLEND_SRC_RGB, (GLint*)&last_blend_src_rgb); + GLenum last_blend_dst_rgb; glGetIntegerv(GL_BLEND_DST_RGB, (GLint*)&last_blend_dst_rgb); + GLenum last_blend_src_alpha; glGetIntegerv(GL_BLEND_SRC_ALPHA, (GLint*)&last_blend_src_alpha); + GLenum last_blend_dst_alpha; glGetIntegerv(GL_BLEND_DST_ALPHA, (GLint*)&last_blend_dst_alpha); + GLenum last_blend_equation_rgb; glGetIntegerv(GL_BLEND_EQUATION_RGB, (GLint*)&last_blend_equation_rgb); + GLenum last_blend_equation_alpha; glGetIntegerv(GL_BLEND_EQUATION_ALPHA, (GLint*)&last_blend_equation_alpha); + GLboolean last_enable_blend = glIsEnabled(GL_BLEND); + GLboolean last_enable_cull_face = glIsEnabled(GL_CULL_FACE); + GLboolean last_enable_depth_test = glIsEnabled(GL_DEPTH_TEST); + GLboolean last_enable_stencil_test = glIsEnabled(GL_STENCIL_TEST); + GLboolean last_enable_scissor_test = glIsEnabled(GL_SCISSOR_TEST); +#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_PRIMITIVE_RESTART + GLboolean last_enable_primitive_restart = (bd->GlVersion >= 310) ? glIsEnabled(GL_PRIMITIVE_RESTART) : GL_FALSE; +#endif + + // Setup desired GL state + // Recreate the VAO every time (this is to easily allow multiple GL contexts to be rendered to. VAO are not shared among GL contexts) + // The renderer would actually work without any VAO bound, but then our VertexAttrib calls would overwrite the default one currently bound. + GLuint vertex_array_object = 0; +#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY + glGenVertexArrays(1, &vertex_array_object); +#endif + ImGui_ImplOpenGL3_SetupRenderState(draw_data, fb_width, fb_height, vertex_array_object); + + // Will project scissor/clipping rectangles into framebuffer space + ImVec2 clip_off = draw_data->DisplayPos; // (0,0) unless using multi-viewports + ImVec2 clip_scale = draw_data->FramebufferScale; // (1,1) unless using retina display which are often (2,2) + + // Render command lists + for (int n = 0; n < draw_data->CmdListsCount; n++) + { + const ImDrawList* cmd_list = draw_data->CmdLists[n]; + + // Upload vertex/index buffers + // - On Intel windows drivers we got reports that regular glBufferData() led to accumulating leaks when using multi-viewports, so we started using orphaning + glBufferSubData(). (See https://github.com/ocornut/imgui/issues/4468) + // - On NVIDIA drivers we got reports that using orphaning + glBufferSubData() led to glitches when using multi-viewports. + // - OpenGL drivers are in a very sorry state in 2022, for now we are switching code path based on vendors. + const GLsizeiptr vtx_buffer_size = (GLsizeiptr)cmd_list->VtxBuffer.Size * (int)sizeof(ImDrawVert); + const GLsizeiptr idx_buffer_size = (GLsizeiptr)cmd_list->IdxBuffer.Size * (int)sizeof(ImDrawIdx); + if (bd->UseBufferSubData) + { + if (bd->VertexBufferSize < vtx_buffer_size) + { + bd->VertexBufferSize = vtx_buffer_size; + glBufferData(GL_ARRAY_BUFFER, bd->VertexBufferSize, NULL, GL_STREAM_DRAW); + } + if (bd->IndexBufferSize < idx_buffer_size) + { + bd->IndexBufferSize = idx_buffer_size; + glBufferData(GL_ELEMENT_ARRAY_BUFFER, bd->IndexBufferSize, NULL, GL_STREAM_DRAW); + } + glBufferSubData(GL_ARRAY_BUFFER, 0, vtx_buffer_size, (const GLvoid*)cmd_list->VtxBuffer.Data); + glBufferSubData(GL_ELEMENT_ARRAY_BUFFER, 0, idx_buffer_size, (const GLvoid*)cmd_list->IdxBuffer.Data); + } + else + { + glBufferData(GL_ARRAY_BUFFER, vtx_buffer_size, (const GLvoid*)cmd_list->VtxBuffer.Data, GL_STREAM_DRAW); + glBufferData(GL_ELEMENT_ARRAY_BUFFER, idx_buffer_size, (const GLvoid*)cmd_list->IdxBuffer.Data, GL_STREAM_DRAW); + } + + for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++) + { + const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i]; + if (pcmd->UserCallback != NULL) + { + // User callback, registered via ImDrawList::AddCallback() + // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.) + if (pcmd->UserCallback == ImDrawCallback_ResetRenderState) + ImGui_ImplOpenGL3_SetupRenderState(draw_data, fb_width, fb_height, vertex_array_object); + else + pcmd->UserCallback(cmd_list, pcmd); + } + else + { + // Project scissor/clipping rectangles into framebuffer space + ImVec2 clip_min((pcmd->ClipRect.x - clip_off.x) * clip_scale.x, (pcmd->ClipRect.y - clip_off.y) * clip_scale.y); + ImVec2 clip_max((pcmd->ClipRect.z - clip_off.x) * clip_scale.x, (pcmd->ClipRect.w - clip_off.y) * clip_scale.y); + if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y) + continue; + + // Apply scissor/clipping rectangle (Y is inverted in OpenGL) + glScissor((int)clip_min.x, (int)((float)fb_height - clip_max.y), (int)(clip_max.x - clip_min.x), (int)(clip_max.y - clip_min.y)); + + // Bind texture, Draw + glBindTexture(GL_TEXTURE_2D, (GLuint)(intptr_t)pcmd->GetTexID()); +#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_VTX_OFFSET + if (bd->GlVersion >= 320) + glDrawElementsBaseVertex(GL_TRIANGLES, (GLsizei)pcmd->ElemCount, sizeof(ImDrawIdx) == 2 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_INT, (void*)(intptr_t)(pcmd->IdxOffset * sizeof(ImDrawIdx)), (GLint)pcmd->VtxOffset); + else +#endif + glDrawElements(GL_TRIANGLES, (GLsizei)pcmd->ElemCount, sizeof(ImDrawIdx) == 2 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_INT, (void*)(intptr_t)(pcmd->IdxOffset * sizeof(ImDrawIdx))); + } + } + } + + // Destroy the temporary VAO +#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY + glDeleteVertexArrays(1, &vertex_array_object); +#endif + + // Restore modified GL state + glUseProgram(last_program); + glBindTexture(GL_TEXTURE_2D, last_texture); +#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_SAMPLER + if (bd->GlVersion >= 330) + glBindSampler(0, last_sampler); +#endif + glActiveTexture(last_active_texture); +#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY + glBindVertexArray(last_vertex_array_object); +#endif + glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer); +#ifndef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY + glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, last_element_array_buffer); + last_vtx_attrib_state_pos.SetState(bd->AttribLocationVtxPos); + last_vtx_attrib_state_uv.SetState(bd->AttribLocationVtxUV); + last_vtx_attrib_state_color.SetState(bd->AttribLocationVtxColor); +#endif + glBlendEquationSeparate(last_blend_equation_rgb, last_blend_equation_alpha); + glBlendFuncSeparate(last_blend_src_rgb, last_blend_dst_rgb, last_blend_src_alpha, last_blend_dst_alpha); + if (last_enable_blend) glEnable(GL_BLEND); else glDisable(GL_BLEND); + if (last_enable_cull_face) glEnable(GL_CULL_FACE); else glDisable(GL_CULL_FACE); + if (last_enable_depth_test) glEnable(GL_DEPTH_TEST); else glDisable(GL_DEPTH_TEST); + if (last_enable_stencil_test) glEnable(GL_STENCIL_TEST); else glDisable(GL_STENCIL_TEST); + if (last_enable_scissor_test) glEnable(GL_SCISSOR_TEST); else glDisable(GL_SCISSOR_TEST); +#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_PRIMITIVE_RESTART + if (bd->GlVersion >= 310) { if (last_enable_primitive_restart) glEnable(GL_PRIMITIVE_RESTART); else glDisable(GL_PRIMITIVE_RESTART); } +#endif + +#ifdef IMGUI_IMPL_HAS_POLYGON_MODE + glPolygonMode(GL_FRONT_AND_BACK, (GLenum)last_polygon_mode[0]); +#endif + glViewport(last_viewport[0], last_viewport[1], (GLsizei)last_viewport[2], (GLsizei)last_viewport[3]); + glScissor(last_scissor_box[0], last_scissor_box[1], (GLsizei)last_scissor_box[2], (GLsizei)last_scissor_box[3]); + (void)bd; // Not all compilation paths use this +} + +bool ImGui_ImplOpenGL3_CreateFontsTexture() +{ + ImGuiIO& io = ImGui::GetIO(); + ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData(); + + // Build texture atlas + unsigned char* pixels; + int width, height; + io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height); // Load as RGBA 32-bit (75% of the memory is wasted, but default font is so small) because it is more likely to be compatible with user's existing shaders. If your ImTextureId represent a higher-level concept than just a GL texture id, consider calling GetTexDataAsAlpha8() instead to save on GPU memory. + + // Upload texture to graphics system + // (Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling) + GLint last_texture; + glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture); + glGenTextures(1, &bd->FontTexture); + glBindTexture(GL_TEXTURE_2D, bd->FontTexture); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); + glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); +#ifdef GL_UNPACK_ROW_LENGTH // Not on WebGL/ES + glPixelStorei(GL_UNPACK_ROW_LENGTH, 0); +#endif + glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixels); + + // Store our identifier + io.Fonts->SetTexID((ImTextureID)(intptr_t)bd->FontTexture); + + // Restore state + glBindTexture(GL_TEXTURE_2D, last_texture); + + return true; +} + +void ImGui_ImplOpenGL3_DestroyFontsTexture() +{ + ImGuiIO& io = ImGui::GetIO(); + ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData(); + if (bd->FontTexture) + { + glDeleteTextures(1, &bd->FontTexture); + io.Fonts->SetTexID(0); + bd->FontTexture = 0; + } +} + +// If you get an error please report on github. You may try different GL context version or GLSL version. See GL<>GLSL version table at the top of this file. +static bool CheckShader(GLuint handle, const char* desc) +{ + ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData(); + GLint status = 0, log_length = 0; + glGetShaderiv(handle, GL_COMPILE_STATUS, &status); + glGetShaderiv(handle, GL_INFO_LOG_LENGTH, &log_length); + if ((GLboolean)status == GL_FALSE) + fprintf(stderr, "ERROR: ImGui_ImplOpenGL3_CreateDeviceObjects: failed to compile %s! With GLSL: %s\n", desc, bd->GlslVersionString); + if (log_length > 1) + { + ImVector<char> buf; + buf.resize((int)(log_length + 1)); + glGetShaderInfoLog(handle, log_length, NULL, (GLchar*)buf.begin()); + fprintf(stderr, "%s\n", buf.begin()); + } + return (GLboolean)status == GL_TRUE; +} + +// If you get an error please report on GitHub. You may try different GL context version or GLSL version. +static bool CheckProgram(GLuint handle, const char* desc) +{ + ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData(); + GLint status = 0, log_length = 0; + glGetProgramiv(handle, GL_LINK_STATUS, &status); + glGetProgramiv(handle, GL_INFO_LOG_LENGTH, &log_length); + if ((GLboolean)status == GL_FALSE) + fprintf(stderr, "ERROR: ImGui_ImplOpenGL3_CreateDeviceObjects: failed to link %s! With GLSL %s\n", desc, bd->GlslVersionString); + if (log_length > 1) + { + ImVector<char> buf; + buf.resize((int)(log_length + 1)); + glGetProgramInfoLog(handle, log_length, NULL, (GLchar*)buf.begin()); + fprintf(stderr, "%s\n", buf.begin()); + } + return (GLboolean)status == GL_TRUE; +} + +bool ImGui_ImplOpenGL3_CreateDeviceObjects() +{ + ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData(); + + // Backup GL state + GLint last_texture, last_array_buffer; + glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture); + glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer); +#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY + GLint last_vertex_array; + glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array); +#endif + + // Parse GLSL version string + int glsl_version = 130; + sscanf(bd->GlslVersionString, "#version %d", &glsl_version); + + const GLchar* vertex_shader_glsl_120 = + "uniform mat4 ProjMtx;\n" + "attribute vec2 Position;\n" + "attribute vec2 UV;\n" + "attribute vec4 Color;\n" + "varying vec2 Frag_UV;\n" + "varying vec4 Frag_Color;\n" + "void main()\n" + "{\n" + " Frag_UV = UV;\n" + " Frag_Color = Color;\n" + " gl_Position = ProjMtx * vec4(Position.xy,0,1);\n" + "}\n"; + + const GLchar* vertex_shader_glsl_130 = + "uniform mat4 ProjMtx;\n" + "in vec2 Position;\n" + "in vec2 UV;\n" + "in vec4 Color;\n" + "out vec2 Frag_UV;\n" + "out vec4 Frag_Color;\n" + "void main()\n" + "{\n" + " Frag_UV = UV;\n" + " Frag_Color = Color;\n" + " gl_Position = ProjMtx * vec4(Position.xy,0,1);\n" + "}\n"; + + const GLchar* vertex_shader_glsl_300_es = + "precision highp float;\n" + "layout (location = 0) in vec2 Position;\n" + "layout (location = 1) in vec2 UV;\n" + "layout (location = 2) in vec4 Color;\n" + "uniform mat4 ProjMtx;\n" + "out vec2 Frag_UV;\n" + "out vec4 Frag_Color;\n" + "void main()\n" + "{\n" + " Frag_UV = UV;\n" + " Frag_Color = Color;\n" + " gl_Position = ProjMtx * vec4(Position.xy,0,1);\n" + "}\n"; + + const GLchar* vertex_shader_glsl_410_core = + "layout (location = 0) in vec2 Position;\n" + "layout (location = 1) in vec2 UV;\n" + "layout (location = 2) in vec4 Color;\n" + "uniform mat4 ProjMtx;\n" + "out vec2 Frag_UV;\n" + "out vec4 Frag_Color;\n" + "void main()\n" + "{\n" + " Frag_UV = UV;\n" + " Frag_Color = Color;\n" + " gl_Position = ProjMtx * vec4(Position.xy,0,1);\n" + "}\n"; + + const GLchar* fragment_shader_glsl_120 = + "#ifdef GL_ES\n" + " precision mediump float;\n" + "#endif\n" + "uniform sampler2D Texture;\n" + "varying vec2 Frag_UV;\n" + "varying vec4 Frag_Color;\n" + "void main()\n" + "{\n" + " gl_FragColor = Frag_Color * texture2D(Texture, Frag_UV.st);\n" + "}\n"; + + const GLchar* fragment_shader_glsl_130 = + "uniform sampler2D Texture;\n" + "in vec2 Frag_UV;\n" + "in vec4 Frag_Color;\n" + "out vec4 Out_Color;\n" + "void main()\n" + "{\n" + " Out_Color = Frag_Color * texture(Texture, Frag_UV.st);\n" + "}\n"; + + const GLchar* fragment_shader_glsl_300_es = + "precision mediump float;\n" + "uniform sampler2D Texture;\n" + "in vec2 Frag_UV;\n" + "in vec4 Frag_Color;\n" + "layout (location = 0) out vec4 Out_Color;\n" + "void main()\n" + "{\n" + " Out_Color = Frag_Color * texture(Texture, Frag_UV.st);\n" + "}\n"; + + const GLchar* fragment_shader_glsl_410_core = + "in vec2 Frag_UV;\n" + "in vec4 Frag_Color;\n" + "uniform sampler2D Texture;\n" + "layout (location = 0) out vec4 Out_Color;\n" + "void main()\n" + "{\n" + " Out_Color = Frag_Color * texture(Texture, Frag_UV.st);\n" + "}\n"; + + // Select shaders matching our GLSL versions + const GLchar* vertex_shader = NULL; + const GLchar* fragment_shader = NULL; + if (glsl_version < 130) + { + vertex_shader = vertex_shader_glsl_120; + fragment_shader = fragment_shader_glsl_120; + } + else if (glsl_version >= 410) + { + vertex_shader = vertex_shader_glsl_410_core; + fragment_shader = fragment_shader_glsl_410_core; + } + else if (glsl_version == 300) + { + vertex_shader = vertex_shader_glsl_300_es; + fragment_shader = fragment_shader_glsl_300_es; + } + else + { + vertex_shader = vertex_shader_glsl_130; + fragment_shader = fragment_shader_glsl_130; + } + + // Create shaders + const GLchar* vertex_shader_with_version[2] = { bd->GlslVersionString, vertex_shader }; + GLuint vert_handle = glCreateShader(GL_VERTEX_SHADER); + glShaderSource(vert_handle, 2, vertex_shader_with_version, NULL); + glCompileShader(vert_handle); + CheckShader(vert_handle, "vertex shader"); + + const GLchar* fragment_shader_with_version[2] = { bd->GlslVersionString, fragment_shader }; + GLuint frag_handle = glCreateShader(GL_FRAGMENT_SHADER); + glShaderSource(frag_handle, 2, fragment_shader_with_version, NULL); + glCompileShader(frag_handle); + CheckShader(frag_handle, "fragment shader"); + + // Link + bd->ShaderHandle = glCreateProgram(); + glAttachShader(bd->ShaderHandle, vert_handle); + glAttachShader(bd->ShaderHandle, frag_handle); + glLinkProgram(bd->ShaderHandle); + CheckProgram(bd->ShaderHandle, "shader program"); + + glDetachShader(bd->ShaderHandle, vert_handle); + glDetachShader(bd->ShaderHandle, frag_handle); + glDeleteShader(vert_handle); + glDeleteShader(frag_handle); + + bd->AttribLocationTex = glGetUniformLocation(bd->ShaderHandle, "Texture"); + bd->AttribLocationProjMtx = glGetUniformLocation(bd->ShaderHandle, "ProjMtx"); + bd->AttribLocationVtxPos = (GLuint)glGetAttribLocation(bd->ShaderHandle, "Position"); + bd->AttribLocationVtxUV = (GLuint)glGetAttribLocation(bd->ShaderHandle, "UV"); + bd->AttribLocationVtxColor = (GLuint)glGetAttribLocation(bd->ShaderHandle, "Color"); + + // Create buffers + glGenBuffers(1, &bd->VboHandle); + glGenBuffers(1, &bd->ElementsHandle); + + ImGui_ImplOpenGL3_CreateFontsTexture(); + + // Restore modified GL state + glBindTexture(GL_TEXTURE_2D, last_texture); + glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer); +#ifdef IMGUI_IMPL_OPENGL_USE_VERTEX_ARRAY + glBindVertexArray(last_vertex_array); +#endif + + return true; +} + +void ImGui_ImplOpenGL3_DestroyDeviceObjects() +{ + ImGui_ImplOpenGL3_Data* bd = ImGui_ImplOpenGL3_GetBackendData(); + if (bd->VboHandle) { glDeleteBuffers(1, &bd->VboHandle); bd->VboHandle = 0; } + if (bd->ElementsHandle) { glDeleteBuffers(1, &bd->ElementsHandle); bd->ElementsHandle = 0; } + if (bd->ShaderHandle) { glDeleteProgram(bd->ShaderHandle); bd->ShaderHandle = 0; } + ImGui_ImplOpenGL3_DestroyFontsTexture(); +} + +//-------------------------------------------------------------------------------------------------------- +// MULTI-VIEWPORT / PLATFORM INTERFACE SUPPORT +// This is an _advanced_ and _optional_ feature, allowing the backend to create and handle multiple viewports simultaneously. +// If you are new to dear imgui or creating a new binding for dear imgui, it is recommended that you completely ignore this section first.. +//-------------------------------------------------------------------------------------------------------- + +static void ImGui_ImplOpenGL3_RenderWindow(ImGuiViewport* viewport, void*) +{ + if (!(viewport->Flags & ImGuiViewportFlags_NoRendererClear)) + { + ImVec4 clear_color = ImVec4(0.0f, 0.0f, 0.0f, 1.0f); + glClearColor(clear_color.x, clear_color.y, clear_color.z, clear_color.w); + glClear(GL_COLOR_BUFFER_BIT); + } + ImGui_ImplOpenGL3_RenderDrawData(viewport->DrawData); +} + +static void ImGui_ImplOpenGL3_InitPlatformInterface() +{ + ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO(); + platform_io.Renderer_RenderWindow = ImGui_ImplOpenGL3_RenderWindow; +} + +static void ImGui_ImplOpenGL3_ShutdownPlatformInterface() +{ + ImGui::DestroyPlatformWindows(); +} + +#if defined(__clang__) +#pragma clang diagnostic pop +#endif |