#include "imgui.h"
#ifndef IMGUI_DISABLE
#include "imgui_impl_opengl2.h"
#include <stdint.h>
#if defined(__clang__)
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wunused-macros"
#pragma clang diagnostic ignored "-Wnonportable-system-include-path"
#endif
#if defined(_WIN32) && !defined(APIENTRY)
#define APIENTRY __stdcall
#endif
#if defined(_WIN32) && !defined(WINGDIAPI)
#define WINGDIAPI __declspec(dllimport)
#endif
#if defined(__APPLE__)
#define GL_SILENCE_DEPRECATION
#include <OpenGL/gl.h>
#else
#include <GL/gl.h>
#endif
#ifdef IMGUI_IMPL_OPENGL_DEBUG
#include <stdio.h>
#define GL_CALL(_CALL) do { _CALL; GLenum gl_err = glGetError(); if (gl_err != 0) fprintf(stderr, "GL error 0x%x returned from '%s'.\n", gl_err, #_CALL); } while (0)
#else
#define GL_CALL(_CALL) _CALL
#endif
struct ImGui_ImplOpenGL2_Data
{
ImGui_ImplOpenGL2_Data() { memset((void*)this, 0, sizeof(*this)); }
};
static ImGui_ImplOpenGL2_Data* ImGui_ImplOpenGL2_GetBackendData()
{
return ImGui::GetCurrentContext() ? (ImGui_ImplOpenGL2_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
}
static void ImGui_ImplOpenGL2_InitMultiViewportSupport();
static void ImGui_ImplOpenGL2_ShutdownMultiViewportSupport();
bool ImGui_ImplOpenGL2_Init()
{
ImGuiIO& io = ImGui::GetIO();
IMGUI_CHECKVERSION();
IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!");
ImGui_ImplOpenGL2_Data* bd = IM_NEW(ImGui_ImplOpenGL2_Data)();
io.BackendRendererUserData = (void*)bd;
io.BackendRendererName = "imgui_impl_opengl2";
io.BackendFlags |= ImGuiBackendFlags_RendererHasTextures; io.BackendFlags |= ImGuiBackendFlags_RendererHasViewports;
ImGui_ImplOpenGL2_InitMultiViewportSupport();
return true;
}
void ImGui_ImplOpenGL2_Shutdown()
{
ImGui_ImplOpenGL2_Data* bd = ImGui_ImplOpenGL2_GetBackendData();
IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
ImGuiIO& io = ImGui::GetIO();
ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
ImGui_ImplOpenGL2_ShutdownMultiViewportSupport();
ImGui_ImplOpenGL2_DestroyDeviceObjects();
io.BackendRendererName = nullptr;
io.BackendRendererUserData = nullptr;
io.BackendFlags &= ~(ImGuiBackendFlags_RendererHasTextures | ImGuiBackendFlags_RendererHasViewports);
platform_io.ClearRendererHandlers();
IM_DELETE(bd);
}
void ImGui_ImplOpenGL2_NewFrame()
{
ImGui_ImplOpenGL2_Data* bd = ImGui_ImplOpenGL2_GetBackendData();
IM_ASSERT(bd != nullptr && "Context or backend not initialized! Did you call ImGui_ImplOpenGL2_Init()?");
IM_UNUSED(bd);
}
static void ImGui_ImplOpenGL2_SetupRenderState(ImDrawData* draw_data, int fb_width, int fb_height)
{
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glDisable(GL_CULL_FACE);
glDisable(GL_DEPTH_TEST);
glDisable(GL_STENCIL_TEST);
glDisable(GL_LIGHTING);
glDisable(GL_COLOR_MATERIAL);
glEnable(GL_SCISSOR_TEST);
glEnableClientState(GL_VERTEX_ARRAY);
glEnableClientState(GL_TEXTURE_COORD_ARRAY);
glEnableClientState(GL_COLOR_ARRAY);
glDisableClientState(GL_NORMAL_ARRAY);
glEnable(GL_TEXTURE_2D);
glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
glShadeModel(GL_SMOOTH);
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
GL_CALL(glViewport(0, 0, (GLsizei)fb_width, (GLsizei)fb_height));
glMatrixMode(GL_PROJECTION);
glPushMatrix();
glLoadIdentity();
glOrtho(draw_data->DisplayPos.x, draw_data->DisplayPos.x + draw_data->DisplaySize.x, draw_data->DisplayPos.y + draw_data->DisplaySize.y, draw_data->DisplayPos.y, -1.0f, +1.0f);
glMatrixMode(GL_MODELVIEW);
glPushMatrix();
glLoadIdentity();
}
void ImGui_ImplOpenGL2_RenderDrawData(ImDrawData* draw_data)
{
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;
if (draw_data->Textures != nullptr)
for (ImTextureData* tex : *draw_data->Textures)
if (tex->Status != ImTextureStatus_OK)
ImGui_ImplOpenGL2_UpdateTexture(tex);
GLint last_texture; glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
GLint last_polygon_mode[2]; glGetIntegerv(GL_POLYGON_MODE, last_polygon_mode);
GLint last_viewport[4]; glGetIntegerv(GL_VIEWPORT, last_viewport);
GLint last_scissor_box[4]; glGetIntegerv(GL_SCISSOR_BOX, last_scissor_box);
GLint last_shade_model; glGetIntegerv(GL_SHADE_MODEL, &last_shade_model);
GLint last_tex_env_mode; glGetTexEnviv(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, &last_tex_env_mode);
glPushAttrib(GL_ENABLE_BIT | GL_COLOR_BUFFER_BIT | GL_TRANSFORM_BIT);
ImGui_ImplOpenGL2_SetupRenderState(draw_data, fb_width, fb_height);
ImVec2 clip_off = draw_data->DisplayPos; ImVec2 clip_scale = draw_data->FramebufferScale;
for (const ImDrawList* draw_list : draw_data->CmdLists)
{
const ImDrawVert* vtx_buffer = draw_list->VtxBuffer.Data;
const ImDrawIdx* idx_buffer = draw_list->IdxBuffer.Data;
glVertexPointer(2, GL_FLOAT, sizeof(ImDrawVert), (const GLvoid*)((const char*)vtx_buffer + offsetof(ImDrawVert, pos)));
glTexCoordPointer(2, GL_FLOAT, sizeof(ImDrawVert), (const GLvoid*)((const char*)vtx_buffer + offsetof(ImDrawVert, uv)));
glColorPointer(4, GL_UNSIGNED_BYTE, sizeof(ImDrawVert), (const GLvoid*)((const char*)vtx_buffer + offsetof(ImDrawVert, col)));
for (int cmd_i = 0; cmd_i < draw_list->CmdBuffer.Size; cmd_i++)
{
const ImDrawCmd* pcmd = &draw_list->CmdBuffer[cmd_i];
if (pcmd->UserCallback)
{
if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
ImGui_ImplOpenGL2_SetupRenderState(draw_data, fb_width, fb_height);
else
pcmd->UserCallback(draw_list, pcmd);
}
else
{
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;
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));
glBindTexture(GL_TEXTURE_2D, (GLuint)(intptr_t)pcmd->GetTexID());
glDrawElements(GL_TRIANGLES, (GLsizei)pcmd->ElemCount, sizeof(ImDrawIdx) == 2 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_INT, idx_buffer + pcmd->IdxOffset);
}
}
}
glDisableClientState(GL_COLOR_ARRAY);
glDisableClientState(GL_TEXTURE_COORD_ARRAY);
glDisableClientState(GL_VERTEX_ARRAY);
glBindTexture(GL_TEXTURE_2D, (GLuint)last_texture);
glMatrixMode(GL_MODELVIEW);
glPopMatrix();
glMatrixMode(GL_PROJECTION);
glPopMatrix();
glPopAttrib();
glPolygonMode(GL_FRONT, (GLenum)last_polygon_mode[0]); glPolygonMode(GL_BACK, (GLenum)last_polygon_mode[1]);
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]);
glShadeModel(last_shade_model);
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, last_tex_env_mode);
}
void ImGui_ImplOpenGL2_UpdateTexture(ImTextureData* tex)
{
if (tex->Status == ImTextureStatus_WantCreate)
{
IM_ASSERT(tex->TexID == ImTextureID_Invalid && tex->BackendUserData == nullptr);
IM_ASSERT(tex->Format == ImTextureFormat_RGBA32);
const void* pixels = tex->GetPixels();
GLuint gl_texture_id = 0;
GLint last_texture;
GL_CALL(glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture));
GL_CALL(glGenTextures(1, &gl_texture_id));
GL_CALL(glBindTexture(GL_TEXTURE_2D, gl_texture_id));
GL_CALL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR));
GL_CALL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR));
GL_CALL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP));
GL_CALL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP));
GL_CALL(glPixelStorei(GL_UNPACK_ROW_LENGTH, 0));
GL_CALL(glPixelStorei(GL_UNPACK_ALIGNMENT, 1));
GL_CALL(glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, tex->Width, tex->Height, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixels));
tex->SetTexID((ImTextureID)(intptr_t)gl_texture_id);
tex->SetStatus(ImTextureStatus_OK);
GL_CALL(glBindTexture(GL_TEXTURE_2D, last_texture));
}
else if (tex->Status == ImTextureStatus_WantUpdates)
{
GLint last_texture;
GL_CALL(glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture));
GLuint gl_tex_id = (GLuint)(intptr_t)tex->TexID;
GL_CALL(glBindTexture(GL_TEXTURE_2D, gl_tex_id));
GL_CALL(glPixelStorei(GL_UNPACK_ROW_LENGTH, tex->Width));
GL_CALL(glPixelStorei(GL_UNPACK_ALIGNMENT, 1));
for (ImTextureRect& r : tex->Updates)
GL_CALL(glTexSubImage2D(GL_TEXTURE_2D, 0, r.x, r.y, r.w, r.h, GL_RGBA, GL_UNSIGNED_BYTE, tex->GetPixelsAt(r.x, r.y)));
GL_CALL(glPixelStorei(GL_UNPACK_ROW_LENGTH, 0));
GL_CALL(glBindTexture(GL_TEXTURE_2D, last_texture)); tex->SetStatus(ImTextureStatus_OK);
}
else if (tex->Status == ImTextureStatus_WantDestroy)
{
GLuint gl_tex_id = (GLuint)(intptr_t)tex->TexID;
glDeleteTextures(1, &gl_tex_id);
tex->SetTexID(ImTextureID_Invalid);
tex->SetStatus(ImTextureStatus_Destroyed);
}
}
bool ImGui_ImplOpenGL2_CreateDeviceObjects()
{
return true;
}
void ImGui_ImplOpenGL2_DestroyDeviceObjects()
{
for (ImTextureData* tex : ImGui::GetPlatformIO().Textures)
if (tex->RefCount == 1)
{
tex->SetStatus(ImTextureStatus_WantDestroy);
ImGui_ImplOpenGL2_UpdateTexture(tex);
}
}
static void ImGui_ImplOpenGL2_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_ImplOpenGL2_RenderDrawData(viewport->DrawData);
}
static void ImGui_ImplOpenGL2_InitMultiViewportSupport()
{
ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
platform_io.Renderer_RenderWindow = ImGui_ImplOpenGL2_RenderWindow;
}
static void ImGui_ImplOpenGL2_ShutdownMultiViewportSupport()
{
ImGui::DestroyPlatformWindows();
}
#if defined(__clang__)
#pragma clang diagnostic pop
#endif
#endif