728 lines
34 KiB
C++
728 lines
34 KiB
C++
// dear imgui: Renderer Backend for modern OpenGL with shaders / programmatic pipeline
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// - Desktop GL: 2.x 3.x 4.x
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// - Embedded GL: ES 2.0 (WebGL 1.0), ES 3.0 (WebGL 2.0)
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// This needs to be used along with a Platform Backend (e.g. GLFW, SDL, Win32, custom..)
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// Implemented features:
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// [X] Renderer: User texture binding. Use 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID!
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// [X] Renderer: Multi-viewport support. Enable with 'io.ConfigFlags |= ImGuiConfigFlags_ViewportsEnable'.
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// [x] Renderer: Desktop GL only: Support for large meshes (64k+ vertices) with 16-bit indices.
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// You can copy and use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
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// If you are new to Dear ImGui, read documentation from the docs/ folder + read the top of imgui.cpp.
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// Read online: https://github.com/ocornut/imgui/tree/master/docs
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// CHANGELOG
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// (minor and older changes stripped away, please see git history for details)
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// 2020-XX-XX: Platform: Added support for multiple windows via the ImGuiPlatformIO interface.
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// 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.
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// 2020-07-10: OpenGL: Added support for glad2 OpenGL loader.
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// 2020-05-08: OpenGL: Made default GLSL version 150 (instead of 130) on OSX.
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// 2020-04-21: OpenGL: Fixed handling of glClipControl(GL_UPPER_LEFT) by inverting projection matrix.
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// 2020-04-12: OpenGL: Fixed context version check mistakenly testing for 4.0+ instead of 3.2+ to enable ImGuiBackendFlags_RendererHasVtxOffset.
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// 2020-03-24: OpenGL: Added support for glbinding 2.x OpenGL loader.
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// 2020-01-07: OpenGL: Added support for glbinding 3.x OpenGL loader.
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// 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.
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// 2019-09-22: OpenGL: Detect default GL loader using __has_include compiler facility.
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// 2019-09-16: OpenGL: Tweak initialization code to allow application calling ImGui_ImplOpenGL3_CreateFontsTexture() before the first NewFrame() call.
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// 2019-05-29: OpenGL: Desktop GL only: Added support for large mesh (64K+ vertices), enable ImGuiBackendFlags_RendererHasVtxOffset flag.
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// 2019-04-30: OpenGL: Added support for special ImDrawCallback_ResetRenderState callback to reset render state.
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// 2019-03-29: OpenGL: Not calling glBindBuffer more than necessary in the render loop.
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// 2019-03-15: OpenGL: Added a GL call + comments in ImGui_ImplOpenGL3_Init() to detect uninitialized GL function loaders early.
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// 2019-03-03: OpenGL: Fix support for ES 2.0 (WebGL 1.0).
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// 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.
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// 2019-02-11: OpenGL: Projecting clipping rectangles correctly using draw_data->FramebufferScale to allow multi-viewports for retina display.
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// 2019-02-01: OpenGL: Using GLSL 410 shaders for any version over 410 (e.g. 430, 450).
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// 2018-11-30: Misc: Setting up io.BackendRendererName so it can be displayed in the About Window.
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// 2018-11-13: OpenGL: Support for GL 4.5's glClipControl(GL_UPPER_LEFT) / GL_CLIP_ORIGIN.
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// 2018-08-29: OpenGL: Added support for more OpenGL loaders: glew and glad, with comments indicative that any loader can be used.
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// 2018-08-09: OpenGL: Default to OpenGL ES 3 on iOS and Android. GLSL version default to "#version 300 ES".
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// 2018-07-30: OpenGL: Support for GLSL 300 ES and 410 core. Fixes for Emscripten compilation.
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// 2018-07-10: OpenGL: Support for more GLSL versions (based on the GLSL version string). Added error output when shaders fail to compile/link.
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// 2018-06-08: Misc: Extracted imgui_impl_opengl3.cpp/.h away from the old combined GLFW/SDL+OpenGL3 examples.
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// 2018-06-08: OpenGL: Use draw_data->DisplayPos and draw_data->DisplaySize to setup projection matrix and clipping rectangle.
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// 2018-05-25: OpenGL: Removed unnecessary backup/restore of GL_ELEMENT_ARRAY_BUFFER_BINDING since this is part of the VAO state.
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// 2018-05-14: OpenGL: Making the call to glBindSampler() optional so 3.2 context won't fail if the function is a NULL pointer.
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// 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".
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// 2018-02-23: OpenGL: Create the VAO in the render function so the setup can more easily be used with multiple shared GL context.
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// 2018-02-16: Misc: Obsoleted the io.RenderDrawListsFn callback and exposed ImGui_ImplSdlGL3_RenderDrawData() in the .h file so you can call it yourself.
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// 2018-01-07: OpenGL: Changed GLSL shader version from 330 to 150.
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// 2017-09-01: OpenGL: Save and restore current bound sampler. Save and restore current polygon mode.
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// 2017-05-01: OpenGL: Fixed save and restore of current blend func state.
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// 2017-05-01: OpenGL: Fixed save and restore of current GL_ACTIVE_TEXTURE.
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// 2016-09-05: OpenGL: Fixed save and restore of current scissor rectangle.
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// 2016-07-29: OpenGL: Explicitly setting GL_UNPACK_ROW_LENGTH to reduce issues because SDL changes it. (#752)
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//----------------------------------------
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// OpenGL GLSL GLSL
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// version version string
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//----------------------------------------
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// 2.0 110 "#version 110"
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// 2.1 120 "#version 120"
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// 3.0 130 "#version 130"
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// 3.1 140 "#version 140"
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// 3.2 150 "#version 150"
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// 3.3 330 "#version 330 core"
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// 4.0 400 "#version 400 core"
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// 4.1 410 "#version 410 core"
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// 4.2 420 "#version 410 core"
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// 4.3 430 "#version 430 core"
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// ES 2.0 100 "#version 100" = WebGL 1.0
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// ES 3.0 300 "#version 300 es" = WebGL 2.0
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//----------------------------------------
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#if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_WARNINGS)
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#define _CRT_SECURE_NO_WARNINGS
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#endif
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#include "imgui.h"
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#include "imgui_impl_opengl3.h"
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#include <stdio.h>
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#if defined(_MSC_VER) && _MSC_VER <= 1500 // MSVC 2008 or earlier
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#include <stddef.h> // intptr_t
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#else
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#include <stdint.h> // intptr_t
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#endif
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// GL includes
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#if defined(IMGUI_IMPL_OPENGL_ES2)
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#include <GLES2/gl2.h>
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#elif defined(IMGUI_IMPL_OPENGL_ES3)
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#if (defined(__APPLE__) && (TARGET_OS_IOS || TARGET_OS_TV))
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#include <OpenGLES/ES3/gl.h> // Use GL ES 3
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#else
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#include <GLES3/gl3.h> // Use GL ES 3
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#endif
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#else
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// About Desktop OpenGL function loaders:
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// Modern desktop OpenGL doesn't have a standard portable header file to load OpenGL function pointers.
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// Helper libraries are often used for this purpose! Here we are supporting a few common ones (gl3w, glew, glad).
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// You may use another loader/header of your choice (glext, glLoadGen, etc.), or chose to manually implement your own.
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#if defined(IMGUI_IMPL_OPENGL_LOADER_GL3W)
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#include <GL/gl3w.h> // Needs to be initialized with gl3wInit() in user's code
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#elif defined(IMGUI_IMPL_OPENGL_LOADER_GLEW)
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#include <GL/glew.h> // Needs to be initialized with glewInit() in user's code.
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#elif defined(IMGUI_IMPL_OPENGL_LOADER_GLAD)
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#include <glad/glad.h> // Needs to be initialized with gladLoadGL() in user's code.
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#elif defined(IMGUI_IMPL_OPENGL_LOADER_GLAD2)
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#include <glad/gl.h> // Needs to be initialized with gladLoadGL(...) or gladLoaderLoadGL() in user's code.
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#elif defined(IMGUI_IMPL_OPENGL_LOADER_GLBINDING2)
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#ifndef GLFW_INCLUDE_NONE
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#define GLFW_INCLUDE_NONE // GLFW including OpenGL headers causes ambiguity or multiple definition errors.
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#endif
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#include <glbinding/Binding.h> // Needs to be initialized with glbinding::Binding::initialize() in user's code.
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#include <glbinding/gl/gl.h>
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using namespace gl;
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#elif defined(IMGUI_IMPL_OPENGL_LOADER_GLBINDING3)
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#ifndef GLFW_INCLUDE_NONE
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#define GLFW_INCLUDE_NONE // GLFW including OpenGL headers causes ambiguity or multiple definition errors.
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#endif
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#include <glbinding/glbinding.h>// Needs to be initialized with glbinding::initialize() in user's code.
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#include <glbinding/gl/gl.h>
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using namespace gl;
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#else
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#include IMGUI_IMPL_OPENGL_LOADER_CUSTOM
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#endif
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#endif
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// Desktop GL 3.2+ has glDrawElementsBaseVertex() which GL ES and WebGL don't have.
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#if !defined(IMGUI_IMPL_OPENGL_ES2) && !defined(IMGUI_IMPL_OPENGL_ES3) && defined(GL_VERSION_3_2)
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#define IMGUI_IMPL_OPENGL_MAY_HAVE_VTX_OFFSET
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#endif
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// Desktop GL 3.3+ has glBindSampler()
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#if !defined(IMGUI_IMPL_OPENGL_ES2) && !defined(IMGUI_IMPL_OPENGL_ES3) && defined(GL_VERSION_3_3)
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#define IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_SAMPLER
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#endif
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// OpenGL Data
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static GLuint g_GlVersion = 0; // Extracted at runtime using GL_MAJOR_VERSION, GL_MINOR_VERSION queries (e.g. 320 for GL 3.2)
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static char g_GlslVersionString[32] = ""; // Specified by user or detected based on compile time GL settings.
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static GLuint g_FontTexture = 0;
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static GLuint g_ShaderHandle = 0, g_VertHandle = 0, g_FragHandle = 0;
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static GLint g_AttribLocationTex = 0, g_AttribLocationProjMtx = 0; // Uniforms location
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static GLuint g_AttribLocationVtxPos = 0, g_AttribLocationVtxUV = 0, g_AttribLocationVtxColor = 0; // Vertex attributes location
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static unsigned int g_VboHandle = 0, g_ElementsHandle = 0;
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// Forward Declarations
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static void ImGui_ImplOpenGL3_InitPlatformInterface();
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static void ImGui_ImplOpenGL3_ShutdownPlatformInterface();
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// Functions
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bool ImGui_ImplOpenGL3_Init(const char* glsl_version)
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{
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// Query for GL version (e.g. 320 for GL 3.2)
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#if !defined(IMGUI_IMPL_OPENGL_ES2)
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GLint major, minor;
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glGetIntegerv(GL_MAJOR_VERSION, &major);
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glGetIntegerv(GL_MINOR_VERSION, &minor);
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g_GlVersion = (GLuint)(major * 100 + minor * 10);
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#else
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g_GlVersion = 200; // GLES 2
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#endif
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// Setup backend capabilities flags
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ImGuiIO& io = ImGui::GetIO();
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io.BackendRendererName = "imgui_impl_opengl3";
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#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_VTX_OFFSET
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if (g_GlVersion >= 320)
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io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset; // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
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#endif
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io.BackendFlags |= ImGuiBackendFlags_RendererHasViewports; // We can create multi-viewports on the Renderer side (optional)
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// Store GLSL version string so we can refer to it later in case we recreate shaders.
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// Note: GLSL version is NOT the same as GL version. Leave this to NULL if unsure.
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#if defined(IMGUI_IMPL_OPENGL_ES2)
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if (glsl_version == NULL)
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glsl_version = "#version 100";
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#elif defined(IMGUI_IMPL_OPENGL_ES3)
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if (glsl_version == NULL)
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glsl_version = "#version 300 es";
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#elif defined(__APPLE__)
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if (glsl_version == NULL)
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glsl_version = "#version 150";
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#else
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if (glsl_version == NULL)
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glsl_version = "#version 130";
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#endif
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IM_ASSERT((int)strlen(glsl_version) + 2 < IM_ARRAYSIZE(g_GlslVersionString));
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strcpy(g_GlslVersionString, glsl_version);
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strcat(g_GlslVersionString, "\n");
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// Debugging construct to make it easily visible in the IDE and debugger which GL loader has been selected.
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// The code actually never uses the 'gl_loader' variable! It is only here so you can read it!
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// If auto-detection fails or doesn't select the same GL loader file as used by your application,
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// you are likely to get a crash below.
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// You can explicitly select a loader by using '#define IMGUI_IMPL_OPENGL_LOADER_XXX' in imconfig.h or compiler command-line.
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const char* gl_loader = "Unknown";
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IM_UNUSED(gl_loader);
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#if defined(IMGUI_IMPL_OPENGL_LOADER_GL3W)
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gl_loader = "GL3W";
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#elif defined(IMGUI_IMPL_OPENGL_LOADER_GLEW)
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gl_loader = "GLEW";
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#elif defined(IMGUI_IMPL_OPENGL_LOADER_GLAD)
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gl_loader = "GLAD";
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#elif defined(IMGUI_IMPL_OPENGL_LOADER_GLAD2)
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gl_loader = "GLAD2";
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#elif defined(IMGUI_IMPL_OPENGL_LOADER_GLBINDING2)
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gl_loader = "glbinding2";
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#elif defined(IMGUI_IMPL_OPENGL_LOADER_GLBINDING3)
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gl_loader = "glbinding3";
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#elif defined(IMGUI_IMPL_OPENGL_LOADER_CUSTOM)
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gl_loader = "custom";
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#else
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gl_loader = "none";
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#endif
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// Make an arbitrary GL call (we don't actually need the result)
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// IF YOU GET A CRASH HERE: it probably means that you haven't initialized the OpenGL function loader used by this code.
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// Desktop OpenGL 3/4 need a function loader. See the IMGUI_IMPL_OPENGL_LOADER_xxx explanation above.
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GLint current_texture;
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glGetIntegerv(GL_TEXTURE_BINDING_2D, ¤t_texture);
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if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
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ImGui_ImplOpenGL3_InitPlatformInterface();
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return true;
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}
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void ImGui_ImplOpenGL3_Shutdown()
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{
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ImGui_ImplOpenGL3_ShutdownPlatformInterface();
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ImGui_ImplOpenGL3_DestroyDeviceObjects();
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}
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void ImGui_ImplOpenGL3_NewFrame()
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{
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if (!g_ShaderHandle)
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ImGui_ImplOpenGL3_CreateDeviceObjects();
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}
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static void ImGui_ImplOpenGL3_SetupRenderState(ImDrawData* draw_data, int fb_width, int fb_height, GLuint vertex_array_object)
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{
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// Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled, polygon fill
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glEnable(GL_BLEND);
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glBlendEquation(GL_FUNC_ADD);
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glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
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glDisable(GL_CULL_FACE);
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glDisable(GL_DEPTH_TEST);
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glEnable(GL_SCISSOR_TEST);
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#ifdef GL_POLYGON_MODE
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glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
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#endif
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// Support for GL 4.5 rarely used glClipControl(GL_UPPER_LEFT)
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bool clip_origin_lower_left = true;
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#if defined(GL_CLIP_ORIGIN) && !defined(__APPLE__)
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GLenum current_clip_origin = 0; glGetIntegerv(GL_CLIP_ORIGIN, (GLint*)¤t_clip_origin);
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if (current_clip_origin == GL_UPPER_LEFT)
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clip_origin_lower_left = false;
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#endif
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// Setup viewport, orthographic projection matrix
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// 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.
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glViewport(0, 0, (GLsizei)fb_width, (GLsizei)fb_height);
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float L = draw_data->DisplayPos.x;
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float R = draw_data->DisplayPos.x + draw_data->DisplaySize.x;
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float T = draw_data->DisplayPos.y;
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float B = draw_data->DisplayPos.y + draw_data->DisplaySize.y;
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if (!clip_origin_lower_left) { float tmp = T; T = B; B = tmp; } // Swap top and bottom if origin is upper left
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const float ortho_projection[4][4] =
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{
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{ 2.0f/(R-L), 0.0f, 0.0f, 0.0f },
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{ 0.0f, 2.0f/(T-B), 0.0f, 0.0f },
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{ 0.0f, 0.0f, -1.0f, 0.0f },
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{ (R+L)/(L-R), (T+B)/(B-T), 0.0f, 1.0f },
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};
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glUseProgram(g_ShaderHandle);
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glUniform1i(g_AttribLocationTex, 0);
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glUniformMatrix4fv(g_AttribLocationProjMtx, 1, GL_FALSE, &ortho_projection[0][0]);
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#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_SAMPLER
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if (g_GlVersion >= 330)
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glBindSampler(0, 0); // We use combined texture/sampler state. Applications using GL 3.3 may set that otherwise.
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#endif
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(void)vertex_array_object;
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#ifndef IMGUI_IMPL_OPENGL_ES2
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glBindVertexArray(vertex_array_object);
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#endif
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// Bind vertex/index buffers and setup attributes for ImDrawVert
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glBindBuffer(GL_ARRAY_BUFFER, g_VboHandle);
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glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, g_ElementsHandle);
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glEnableVertexAttribArray(g_AttribLocationVtxPos);
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glEnableVertexAttribArray(g_AttribLocationVtxUV);
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glEnableVertexAttribArray(g_AttribLocationVtxColor);
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glVertexAttribPointer(g_AttribLocationVtxPos, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)IM_OFFSETOF(ImDrawVert, pos));
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glVertexAttribPointer(g_AttribLocationVtxUV, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)IM_OFFSETOF(ImDrawVert, uv));
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glVertexAttribPointer(g_AttribLocationVtxColor, 4, GL_UNSIGNED_BYTE, GL_TRUE, sizeof(ImDrawVert), (GLvoid*)IM_OFFSETOF(ImDrawVert, col));
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}
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// OpenGL3 Render function.
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// Note that this implementation is little overcomplicated because we are saving/setting up/restoring every OpenGL state explicitly.
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// This is in order to be able to run within an OpenGL engine that doesn't do so.
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void ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data)
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{
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// Avoid rendering when minimized, scale coordinates for retina displays (screen coordinates != framebuffer coordinates)
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int fb_width = (int)(draw_data->DisplaySize.x * draw_data->FramebufferScale.x);
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int fb_height = (int)(draw_data->DisplaySize.y * draw_data->FramebufferScale.y);
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if (fb_width <= 0 || fb_height <= 0)
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return;
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// Backup GL state
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GLenum last_active_texture; glGetIntegerv(GL_ACTIVE_TEXTURE, (GLint*)&last_active_texture);
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glActiveTexture(GL_TEXTURE0);
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GLuint last_program; glGetIntegerv(GL_CURRENT_PROGRAM, (GLint*)&last_program);
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GLuint last_texture; glGetIntegerv(GL_TEXTURE_BINDING_2D, (GLint*)&last_texture);
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#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_SAMPLER
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GLuint last_sampler; if (g_GlVersion >= 330) { glGetIntegerv(GL_SAMPLER_BINDING, (GLint*)&last_sampler); } else { last_sampler = 0; }
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#endif
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GLuint last_array_buffer; glGetIntegerv(GL_ARRAY_BUFFER_BINDING, (GLint*)&last_array_buffer);
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#ifndef IMGUI_IMPL_OPENGL_ES2
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GLuint last_vertex_array_object; glGetIntegerv(GL_VERTEX_ARRAY_BINDING, (GLint*)&last_vertex_array_object);
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#endif
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#ifdef GL_POLYGON_MODE
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GLint last_polygon_mode[2]; glGetIntegerv(GL_POLYGON_MODE, last_polygon_mode);
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#endif
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GLint last_viewport[4]; glGetIntegerv(GL_VIEWPORT, last_viewport);
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GLint last_scissor_box[4]; glGetIntegerv(GL_SCISSOR_BOX, last_scissor_box);
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GLenum last_blend_src_rgb; glGetIntegerv(GL_BLEND_SRC_RGB, (GLint*)&last_blend_src_rgb);
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GLenum last_blend_dst_rgb; glGetIntegerv(GL_BLEND_DST_RGB, (GLint*)&last_blend_dst_rgb);
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GLenum last_blend_src_alpha; glGetIntegerv(GL_BLEND_SRC_ALPHA, (GLint*)&last_blend_src_alpha);
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GLenum last_blend_dst_alpha; glGetIntegerv(GL_BLEND_DST_ALPHA, (GLint*)&last_blend_dst_alpha);
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GLenum last_blend_equation_rgb; glGetIntegerv(GL_BLEND_EQUATION_RGB, (GLint*)&last_blend_equation_rgb);
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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_scissor_test = glIsEnabled(GL_SCISSOR_TEST);
|
|
|
|
// 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;
|
|
#ifndef IMGUI_IMPL_OPENGL_ES2
|
|
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
|
|
glBufferData(GL_ARRAY_BUFFER, (GLsizeiptr)cmd_list->VtxBuffer.Size * (int)sizeof(ImDrawVert), (const GLvoid*)cmd_list->VtxBuffer.Data, GL_STREAM_DRAW);
|
|
glBufferData(GL_ELEMENT_ARRAY_BUFFER, (GLsizeiptr)cmd_list->IdxBuffer.Size * (int)sizeof(ImDrawIdx), (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
|
|
ImVec4 clip_rect;
|
|
clip_rect.x = (pcmd->ClipRect.x - clip_off.x) * clip_scale.x;
|
|
clip_rect.y = (pcmd->ClipRect.y - clip_off.y) * clip_scale.y;
|
|
clip_rect.z = (pcmd->ClipRect.z - clip_off.x) * clip_scale.x;
|
|
clip_rect.w = (pcmd->ClipRect.w - clip_off.y) * clip_scale.y;
|
|
|
|
if (clip_rect.x < fb_width && clip_rect.y < fb_height && clip_rect.z >= 0.0f && clip_rect.w >= 0.0f)
|
|
{
|
|
// Apply scissor/clipping rectangle
|
|
glScissor((int)clip_rect.x, (int)(fb_height - clip_rect.w), (int)(clip_rect.z - clip_rect.x), (int)(clip_rect.w - clip_rect.y));
|
|
|
|
// Bind texture, Draw
|
|
glBindTexture(GL_TEXTURE_2D, (GLuint)(intptr_t)pcmd->TextureId);
|
|
#ifdef IMGUI_IMPL_OPENGL_MAY_HAVE_VTX_OFFSET
|
|
if (g_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
|
|
#ifndef IMGUI_IMPL_OPENGL_ES2
|
|
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 (g_GlVersion >= 330)
|
|
glBindSampler(0, last_sampler);
|
|
#endif
|
|
glActiveTexture(last_active_texture);
|
|
#ifndef IMGUI_IMPL_OPENGL_ES2
|
|
glBindVertexArray(last_vertex_array_object);
|
|
#endif
|
|
glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer);
|
|
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_scissor_test) glEnable(GL_SCISSOR_TEST); else glDisable(GL_SCISSOR_TEST);
|
|
#ifdef GL_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]);
|
|
}
|
|
|
|
bool ImGui_ImplOpenGL3_CreateFontsTexture()
|
|
{
|
|
// Build texture atlas
|
|
ImGuiIO& io = ImGui::GetIO();
|
|
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
|
|
GLint last_texture;
|
|
glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
|
|
glGenTextures(1, &g_FontTexture);
|
|
glBindTexture(GL_TEXTURE_2D, g_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
|
|
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->TexID = (ImTextureID)(intptr_t)g_FontTexture;
|
|
|
|
// Restore state
|
|
glBindTexture(GL_TEXTURE_2D, last_texture);
|
|
|
|
return true;
|
|
}
|
|
|
|
void ImGui_ImplOpenGL3_DestroyFontsTexture()
|
|
{
|
|
if (g_FontTexture)
|
|
{
|
|
ImGuiIO& io = ImGui::GetIO();
|
|
glDeleteTextures(1, &g_FontTexture);
|
|
io.Fonts->TexID = 0;
|
|
g_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)
|
|
{
|
|
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!\n", desc);
|
|
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)
|
|
{
|
|
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, g_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()
|
|
{
|
|
// Backup GL state
|
|
GLint last_texture, last_array_buffer;
|
|
glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
|
|
glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer);
|
|
#ifndef IMGUI_IMPL_OPENGL_ES2
|
|
GLint last_vertex_array;
|
|
glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array);
|
|
#endif
|
|
|
|
// Parse GLSL version string
|
|
int glsl_version = 130;
|
|
sscanf(g_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 mediump 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] = { g_GlslVersionString, vertex_shader };
|
|
g_VertHandle = glCreateShader(GL_VERTEX_SHADER);
|
|
glShaderSource(g_VertHandle, 2, vertex_shader_with_version, NULL);
|
|
glCompileShader(g_VertHandle);
|
|
CheckShader(g_VertHandle, "vertex shader");
|
|
|
|
const GLchar* fragment_shader_with_version[2] = { g_GlslVersionString, fragment_shader };
|
|
g_FragHandle = glCreateShader(GL_FRAGMENT_SHADER);
|
|
glShaderSource(g_FragHandle, 2, fragment_shader_with_version, NULL);
|
|
glCompileShader(g_FragHandle);
|
|
CheckShader(g_FragHandle, "fragment shader");
|
|
|
|
g_ShaderHandle = glCreateProgram();
|
|
glAttachShader(g_ShaderHandle, g_VertHandle);
|
|
glAttachShader(g_ShaderHandle, g_FragHandle);
|
|
glLinkProgram(g_ShaderHandle);
|
|
CheckProgram(g_ShaderHandle, "shader program");
|
|
|
|
g_AttribLocationTex = glGetUniformLocation(g_ShaderHandle, "Texture");
|
|
g_AttribLocationProjMtx = glGetUniformLocation(g_ShaderHandle, "ProjMtx");
|
|
g_AttribLocationVtxPos = (GLuint)glGetAttribLocation(g_ShaderHandle, "Position");
|
|
g_AttribLocationVtxUV = (GLuint)glGetAttribLocation(g_ShaderHandle, "UV");
|
|
g_AttribLocationVtxColor = (GLuint)glGetAttribLocation(g_ShaderHandle, "Color");
|
|
|
|
// Create buffers
|
|
glGenBuffers(1, &g_VboHandle);
|
|
glGenBuffers(1, &g_ElementsHandle);
|
|
|
|
ImGui_ImplOpenGL3_CreateFontsTexture();
|
|
|
|
// Restore modified GL state
|
|
glBindTexture(GL_TEXTURE_2D, last_texture);
|
|
glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer);
|
|
#ifndef IMGUI_IMPL_OPENGL_ES2
|
|
glBindVertexArray(last_vertex_array);
|
|
#endif
|
|
|
|
return true;
|
|
}
|
|
|
|
void ImGui_ImplOpenGL3_DestroyDeviceObjects()
|
|
{
|
|
if (g_VboHandle) { glDeleteBuffers(1, &g_VboHandle); g_VboHandle = 0; }
|
|
if (g_ElementsHandle) { glDeleteBuffers(1, &g_ElementsHandle); g_ElementsHandle = 0; }
|
|
if (g_ShaderHandle && g_VertHandle) { glDetachShader(g_ShaderHandle, g_VertHandle); }
|
|
if (g_ShaderHandle && g_FragHandle) { glDetachShader(g_ShaderHandle, g_FragHandle); }
|
|
if (g_VertHandle) { glDeleteShader(g_VertHandle); g_VertHandle = 0; }
|
|
if (g_FragHandle) { glDeleteShader(g_FragHandle); g_FragHandle = 0; }
|
|
if (g_ShaderHandle) { glDeleteProgram(g_ShaderHandle); g_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();
|
|
}
|