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mirror of https://github.com/ocornut/imgui.git synced 2024-11-24 07:40:22 +01:00

Merge branch 'SDL_OpenGL3_Implementation' of https://github.com/zach2good/imgui into zach2good-SDL_OpenGL3_Implementation

This commit is contained in:
ocornut 2015-11-16 21:35:49 +01:00
commit 9a8cbf128d
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# How to Build
Link
===
OpenGL
SDL2
GLEW

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// ImGui SDL2 binding with OpenGL3
// https://github.com/ocornut/imgui
#include <SDL.h>
#include <SDL_syswm.h>
#include <GL/glew.h>
#include "imgui.h"
#include "imgui_impl_sdlogl3.h"
// Data
static SDL_Window* g_Window = NULL;
static double g_Time = 0.0f;
static bool g_MousePressed[3] = { false, false, false };
static float g_MouseWheel = 0.0f;
static GLuint g_FontTexture = 0;
static int g_ShaderHandle = 0, g_VertHandle = 0, g_FragHandle = 0;
static int g_AttribLocationTex = 0, g_AttribLocationProjMtx = 0;
static int g_AttribLocationPosition = 0, g_AttribLocationUV = 0, g_AttribLocationColor = 0;
static unsigned int g_VboHandle = 0, g_VaoHandle = 0, g_ElementsHandle = 0;
// This is the main rendering function that you have to implement and provide to ImGui (via setting up 'RenderDrawListsFn' in the ImGuiIO structure)
// If text or lines are blurry when integrating ImGui in your engine:
// - in your Render function, try translating your projection matrix by (0.5f,0.5f) or (0.375f,0.375f)
void ImGui_ImplSdlOgl3_RenderDrawLists(ImDrawData* draw_data)
{
// Backup GL state
GLint last_program; glGetIntegerv(GL_CURRENT_PROGRAM, &last_program);
GLint last_texture; glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
GLint last_array_buffer; glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer);
GLint last_element_array_buffer; glGetIntegerv(GL_ELEMENT_ARRAY_BUFFER_BINDING, &last_element_array_buffer);
GLint last_vertex_array; glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array);
GLint last_blend_src; glGetIntegerv(GL_BLEND_SRC, &last_blend_src);
GLint last_blend_dst; glGetIntegerv(GL_BLEND_DST, &last_blend_dst);
GLint last_blend_equation_rgb; glGetIntegerv(GL_BLEND_EQUATION_RGB, &last_blend_equation_rgb);
GLint last_blend_equation_alpha; glGetIntegerv(GL_BLEND_EQUATION_ALPHA, &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 render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled
glEnable(GL_BLEND);
glBlendEquation(GL_FUNC_ADD);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glDisable(GL_CULL_FACE);
glDisable(GL_DEPTH_TEST);
glEnable(GL_SCISSOR_TEST);
glActiveTexture(GL_TEXTURE0);
// Handle cases of screen coordinates != from framebuffer coordinates (e.g. retina displays)
ImGuiIO& io = ImGui::GetIO();
float fb_height = io.DisplaySize.y * io.DisplayFramebufferScale.y;
draw_data->ScaleClipRects(io.DisplayFramebufferScale);
// Setup orthographic projection matrix
const float ortho_projection[4][4] =
{
{ 2.0f / io.DisplaySize.x, 0.0f, 0.0f, 0.0f },
{ 0.0f, 2.0f / -io.DisplaySize.y, 0.0f, 0.0f },
{ 0.0f, 0.0f, -1.0f, 0.0f },
{ -1.0f, 1.0f, 0.0f, 1.0f },
};
glUseProgram(g_ShaderHandle);
glUniform1i(g_AttribLocationTex, 0);
glUniformMatrix4fv(g_AttribLocationProjMtx, 1, GL_FALSE, &ortho_projection[0][0]);
glBindVertexArray(g_VaoHandle);
for (int n = 0; n < draw_data->CmdListsCount; n++)
{
const ImDrawList* cmd_list = draw_data->CmdLists[n];
const ImDrawIdx* idx_buffer_offset = 0;
glBindBuffer(GL_ARRAY_BUFFER, g_VboHandle);
glBufferData(GL_ARRAY_BUFFER, (GLsizeiptr)cmd_list->VtxBuffer.size() * sizeof(ImDrawVert), (GLvoid*)&cmd_list->VtxBuffer.front(), GL_STREAM_DRAW);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, g_ElementsHandle);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, (GLsizeiptr)cmd_list->IdxBuffer.size() * sizeof(ImDrawIdx), (GLvoid*)&cmd_list->IdxBuffer.front(), GL_STREAM_DRAW);
for (const ImDrawCmd* pcmd = cmd_list->CmdBuffer.begin(); pcmd != cmd_list->CmdBuffer.end(); pcmd++)
{
if (pcmd->UserCallback)
{
pcmd->UserCallback(cmd_list, pcmd);
}
else
{
glBindTexture(GL_TEXTURE_2D, (GLuint)(intptr_t)pcmd->TextureId);
glScissor((int)pcmd->ClipRect.x, (int)(fb_height - pcmd->ClipRect.w), (int)(pcmd->ClipRect.z - pcmd->ClipRect.x), (int)(pcmd->ClipRect.w - pcmd->ClipRect.y));
glDrawElements(GL_TRIANGLES, (GLsizei)pcmd->ElemCount, GL_UNSIGNED_SHORT, idx_buffer_offset);
}
idx_buffer_offset += pcmd->ElemCount;
}
}
// Restore modified GL state
glUseProgram(last_program);
glBindTexture(GL_TEXTURE_2D, last_texture);
glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, last_element_array_buffer);
glBindVertexArray(last_vertex_array);
glBlendEquationSeparate(last_blend_equation_rgb, last_blend_equation_alpha);
glBlendFunc(last_blend_src, last_blend_dst);
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);
}
static const char* ImGui_ImplSdlOgl3_GetClipboardText()
{
return SDL_GetClipboardText();
}
static void ImGui_ImplSdlOgl3_SetClipboardText(const char* text)
{
SDL_SetClipboardText(text);
}
bool ImGui_ImplSdlOgl3_ProcessEvent(SDL_Event* event)
{
ImGuiIO& io = ImGui::GetIO();
switch (event->type)
{
case SDL_MOUSEWHEEL:
{
if (event->wheel.y > 0)
g_MouseWheel = 1;
if (event->wheel.y < 0)
g_MouseWheel = -1;
return true;
}
case SDL_MOUSEBUTTONDOWN:
{
if (event->button.button == SDL_BUTTON_LEFT) g_MousePressed[0] = true;
if (event->button.button == SDL_BUTTON_RIGHT) g_MousePressed[1] = true;
if (event->button.button == SDL_BUTTON_MIDDLE) g_MousePressed[2] = true;
return true;
}
case SDL_TEXTINPUT:
{
ImGuiIO& io = ImGui::GetIO();
io.AddInputCharactersUTF8(event->text.text);
return true;
}
case SDL_KEYDOWN:
case SDL_KEYUP:
{
int key = event->key.keysym.sym & ~SDLK_SCANCODE_MASK;
io.KeysDown[key] = (event->type == SDL_KEYDOWN);
io.KeyShift = ((SDL_GetModState() & KMOD_SHIFT) != 0);
io.KeyCtrl = ((SDL_GetModState() & KMOD_CTRL) != 0);
io.KeyAlt = ((SDL_GetModState() & KMOD_ALT) != 0);
return true;
}
}
return false;
}
void ImGui_ImplSdlOgl3_CreateFontsTexture()
{
ImGuiIO& io = ImGui::GetIO();
// Build texture atlas
unsigned char* pixels;
int width, height;
io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height); // Load as RGBA 32-bits for OpenGL3 demo because it is more likely to be compatible with user's existing shader.
// Create OpenGL 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);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixels);
// Store our identifier
io.Fonts->TexID = (void *)(intptr_t)g_FontTexture;
// Cleanup (don't clear the input data if you want to append new fonts later)
io.Fonts->ClearInputData();
io.Fonts->ClearTexData();
}
bool ImGui_ImplSdlOgl3_CreateDeviceObjects()
{
// Backup GL state
GLint last_texture, last_array_buffer, last_vertex_array;
glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer);
glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array);
const GLchar *vertex_shader =
"#version 330\n"
"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* fragment_shader =
"#version 330\n"
"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";
g_ShaderHandle = glCreateProgram();
g_VertHandle = glCreateShader(GL_VERTEX_SHADER);
g_FragHandle = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource(g_VertHandle, 1, &vertex_shader, 0);
glShaderSource(g_FragHandle, 1, &fragment_shader, 0);
glCompileShader(g_VertHandle);
glCompileShader(g_FragHandle);
glAttachShader(g_ShaderHandle, g_VertHandle);
glAttachShader(g_ShaderHandle, g_FragHandle);
glLinkProgram(g_ShaderHandle);
g_AttribLocationTex = glGetUniformLocation(g_ShaderHandle, "Texture");
g_AttribLocationProjMtx = glGetUniformLocation(g_ShaderHandle, "ProjMtx");
g_AttribLocationPosition = glGetAttribLocation(g_ShaderHandle, "Position");
g_AttribLocationUV = glGetAttribLocation(g_ShaderHandle, "UV");
g_AttribLocationColor = glGetAttribLocation(g_ShaderHandle, "Color");
glGenBuffers(1, &g_VboHandle);
glGenBuffers(1, &g_ElementsHandle);
glGenVertexArrays(1, &g_VaoHandle);
glBindVertexArray(g_VaoHandle);
glBindBuffer(GL_ARRAY_BUFFER, g_VboHandle);
glEnableVertexAttribArray(g_AttribLocationPosition);
glEnableVertexAttribArray(g_AttribLocationUV);
glEnableVertexAttribArray(g_AttribLocationColor);
#define OFFSETOF(TYPE, ELEMENT) ((size_t)&(((TYPE *)0)->ELEMENT))
glVertexAttribPointer(g_AttribLocationPosition, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)OFFSETOF(ImDrawVert, pos));
glVertexAttribPointer(g_AttribLocationUV, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)OFFSETOF(ImDrawVert, uv));
glVertexAttribPointer(g_AttribLocationColor, 4, GL_UNSIGNED_BYTE, GL_TRUE, sizeof(ImDrawVert), (GLvoid*)OFFSETOF(ImDrawVert, col));
#undef OFFSETOF
ImGui_ImplSdlOgl3_CreateFontsTexture();
// Restore modified GL state
glBindTexture(GL_TEXTURE_2D, last_texture);
glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer);
glBindVertexArray(last_vertex_array);
return true;
}
void ImGui_ImplSdlOgl3_InvalidateDeviceObjects()
{
if (g_FontTexture)
{
glDeleteTextures(1, &g_FontTexture);
ImGui::GetIO().Fonts->TexID = 0;
g_FontTexture = 0;
}
}
bool ImGui_ImplSdlOgl3_Init(SDL_Window *window)
{
g_Window = window;
ImGuiIO& io = ImGui::GetIO();
io.KeyMap[ImGuiKey_Tab] = SDLK_TAB; // Keyboard mapping. ImGui will use those indices to peek into the io.KeyDown[] array.
io.KeyMap[ImGuiKey_LeftArrow] = SDL_SCANCODE_LEFT;
io.KeyMap[ImGuiKey_RightArrow] = SDL_SCANCODE_RIGHT;
io.KeyMap[ImGuiKey_UpArrow] = SDL_SCANCODE_UP;
io.KeyMap[ImGuiKey_DownArrow] = SDL_SCANCODE_DOWN;
io.KeyMap[ImGuiKey_PageUp] = SDL_SCANCODE_PAGEUP;
io.KeyMap[ImGuiKey_PageDown] = SDL_SCANCODE_PAGEDOWN;
io.KeyMap[ImGuiKey_Home] = SDL_SCANCODE_HOME;
io.KeyMap[ImGuiKey_End] = SDL_SCANCODE_END;
io.KeyMap[ImGuiKey_Delete] = SDLK_DELETE;
io.KeyMap[ImGuiKey_Backspace] = SDLK_BACKSPACE;
io.KeyMap[ImGuiKey_Enter] = SDLK_RETURN;
io.KeyMap[ImGuiKey_Escape] = SDLK_ESCAPE;
io.KeyMap[ImGuiKey_A] = SDLK_a;
io.KeyMap[ImGuiKey_C] = SDLK_c;
io.KeyMap[ImGuiKey_V] = SDLK_v;
io.KeyMap[ImGuiKey_X] = SDLK_x;
io.KeyMap[ImGuiKey_Y] = SDLK_y;
io.KeyMap[ImGuiKey_Z] = SDLK_z;
io.RenderDrawListsFn = ImGui_ImplSdlOgl3_RenderDrawLists; // Alternatively you can set this to NULL and call ImGui::GetDrawData() after ImGui::Render() to get the same ImDrawData pointer.
io.SetClipboardTextFn = ImGui_ImplSdlOgl3_SetClipboardText;
io.GetClipboardTextFn = ImGui_ImplSdlOgl3_GetClipboardText;
#ifdef _WIN32
SDL_SysWMinfo wmInfo;
SDL_VERSION(&wmInfo.version);
SDL_GetWindowWMInfo(window, &wmInfo);
io.ImeWindowHandle = wmInfo.info.win.window;
#endif
return true;
}
void ImGui_ImplSdlOgl3_Shutdown()
{
if (g_VaoHandle) glDeleteVertexArrays(1, &g_VaoHandle);
if (g_VboHandle) glDeleteBuffers(1, &g_VboHandle);
if (g_ElementsHandle) glDeleteBuffers(1, &g_ElementsHandle);
g_VaoHandle = g_VboHandle = g_ElementsHandle = 0;
glDetachShader(g_ShaderHandle, g_VertHandle);
glDeleteShader(g_VertHandle);
g_VertHandle = 0;
glDetachShader(g_ShaderHandle, g_FragHandle);
glDeleteShader(g_FragHandle);
g_FragHandle = 0;
glDeleteProgram(g_ShaderHandle);
g_ShaderHandle = 0;
if (g_FontTexture)
{
glDeleteTextures(1, &g_FontTexture);
ImGui::GetIO().Fonts->TexID = 0;
g_FontTexture = 0;
}
ImGui::Shutdown();
}
void ImGui_ImplSdlOgl3_NewFrame(SDL_Window *window)
{
if (!g_FontTexture)
ImGui_ImplSdlOgl3_CreateDeviceObjects();
ImGuiIO& io = ImGui::GetIO();
// Setup display size (every frame to accommodate for window resizing)
int w, h;
int display_w, display_h;
SDL_GetWindowSize(window, &w, &h);
SDL_GetWindowSize(window, &display_w, &display_h);
io.DisplaySize = ImVec2((float)w, (float)h);
io.DisplayFramebufferScale = ImVec2((float)display_w / w, (float)display_h / h);
// Setup time step
Uint32 time = SDL_GetTicks();
double current_time = time / 1000.0;
io.DeltaTime = g_Time > 0.0 ? (float)(current_time - g_Time) : (float)(1.0f / 60.0f);
g_Time = current_time;
// Setup inputs
// (we already got mouse wheel, keyboard keys & characters from glfw callbacks polled in glfwPollEvents())
int mx, my;
Uint32 mouseMask = SDL_GetMouseState(&mx, &my);
if (SDL_GetWindowFlags(window) & SDL_WINDOW_MOUSE_FOCUS)
io.MousePos = ImVec2((float)mx, (float)my); // Mouse position, in pixels (set to -1,-1 if no mouse / on another screen, etc.)
else
io.MousePos = ImVec2(-1, -1);
io.MouseDown[0] = g_MousePressed[0] || (mouseMask & SDL_BUTTON(SDL_BUTTON_LEFT)) != 0; // If a mouse press event came, always pass it as "mouse held this frame", so we don't miss click-release events that are shorter than 1 frame.
io.MouseDown[1] = g_MousePressed[1] || (mouseMask & SDL_BUTTON(SDL_BUTTON_RIGHT)) != 0;
io.MouseDown[2] = g_MousePressed[2] || (mouseMask & SDL_BUTTON(SDL_BUTTON_MIDDLE)) != 0;
g_MousePressed[0] = g_MousePressed[1] = g_MousePressed[2] = false;
io.MouseWheel = g_MouseWheel;
g_MouseWheel = 0.0f;
// Hide OS mouse cursor if ImGui is drawing it
SDL_ShowCursor(io.MouseDrawCursor ? 0 : 1);
// Start the frame
ImGui::NewFrame();
}

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// ImGui SDL2 binding with OpenGL3
// https://github.com/ocornut/imgui
struct SDL_Window;
typedef union SDL_Event SDL_Event;
IMGUI_API bool ImGui_ImplSdlOgl3_Init(SDL_Window *window);
IMGUI_API void ImGui_ImplSdlOgl3_Shutdown();
IMGUI_API void ImGui_ImplSdlOgl3_NewFrame(SDL_Window *window);
IMGUI_API bool ImGui_ImplSdlOgl3_ProcessEvent(SDL_Event* event);
// Use if you want to reset your rendering device without losing ImGui state.
IMGUI_API void ImGui_ImplSdlOgl3_InvalidateDeviceObjects();
IMGUI_API bool ImGui_ImplSdlOgl3_CreateDeviceObjects();

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// ImGui - standalone example application for SDL2 + OpenGL
#include <imgui.h>
#include "imgui_impl_sdlogl3.h"
#include <stdio.h>
#include <SDL.h>
#include <GL/glew.h>
int main(int, char**)
{
// Setup SDL
if (SDL_Init(SDL_INIT_EVERYTHING) != 0)
{
printf("Error: %s\n", SDL_GetError());
return -1;
}
// Setup window
SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 2);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 2);
SDL_DisplayMode current;
SDL_GetCurrentDisplayMode(0, &current);
SDL_Window *window = SDL_CreateWindow("ImGui SDL2+OpenGL example", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 1280, 720, SDL_WINDOW_OPENGL|SDL_WINDOW_RESIZABLE);
SDL_GLContext glcontext = SDL_GL_CreateContext(window);
// Setup ImGui binding
ImGui_ImplSdlOgl3_Init(window);
// Load Fonts
// (see extra_fonts/README.txt for more details)
//ImGuiIO& io = ImGui::GetIO();
//io.Fonts->AddFontDefault();
//io.Fonts->AddFontFromFileTTF("../../extra_fonts/Cousine-Regular.ttf", 15.0f);
//io.Fonts->AddFontFromFileTTF("../../extra_fonts/DroidSans.ttf", 16.0f);
//io.Fonts->AddFontFromFileTTF("../../extra_fonts/ProggyClean.ttf", 13.0f);
//io.Fonts->AddFontFromFileTTF("../../extra_fonts/ProggyTiny.ttf", 10.0f);
//io.Fonts->AddFontFromFileTTF("c:\\Windows\\Fonts\\ArialUni.ttf", 18.0f, NULL, io.Fonts->GetGlyphRangesJapanese());
// Merge glyphs from multiple fonts into one (e.g. combine default font with another with Chinese glyphs, or add icons)
//ImWchar icons_ranges[] = { 0xf000, 0xf3ff, 0 };
//ImFontConfig icons_config; icons_config.MergeMode = true; icons_config.PixelSnapH = true;
//io.Fonts->AddFontFromFileTTF("../../extra_fonts/DroidSans.ttf", 18.0f);
//io.Fonts->AddFontFromFileTTF("../../extra_fonts/fontawesome-webfont.ttf", 18.0f, &icons_config, icons_ranges);
bool show_test_window = true;
bool show_another_window = false;
ImVec4 clear_color = ImColor(114, 144, 154);
// Main loop
bool done = false;
while (!done)
{
SDL_Event event;
while (SDL_PollEvent(&event))
{
ImGui_ImplSdlOgl3_ProcessEvent(&event);
if (event.type == SDL_QUIT)
done = true;
}
ImGui_ImplSdlOgl3_NewFrame(window);
// 1. Show a simple window
// Tip: if we don't call ImGui::Begin()/ImGui::End() the widgets appears in a window automatically called "Debug"
{
static float f = 0.0f;
ImGui::Text("Hello, world!");
ImGui::SliderFloat("float", &f, 0.0f, 1.0f);
ImGui::ColorEdit3("clear color", (float*)&clear_color);
if (ImGui::Button("Test Window")) show_test_window ^= 1;
if (ImGui::Button("Another Window")) show_another_window ^= 1;
ImGui::Text("Application average %.3f ms/frame (%.1f FPS)", 1000.0f / ImGui::GetIO().Framerate, ImGui::GetIO().Framerate);
}
// 2. Show another simple window, this time using an explicit Begin/End pair
if (show_another_window)
{
ImGui::SetNextWindowSize(ImVec2(200,100), ImGuiSetCond_FirstUseEver);
ImGui::Begin("Another Window", &show_another_window);
ImGui::Text("Hello");
ImGui::End();
}
// 3. Show the ImGui test window. Most of the sample code is in ImGui::ShowTestWindow()
if (show_test_window)
{
ImGui::SetNextWindowPos(ImVec2(650, 20), ImGuiSetCond_FirstUseEver);
ImGui::ShowTestWindow(&show_test_window);
}
// Rendering
glViewport(0, 0, (int)ImGui::GetIO().DisplaySize.x, (int)ImGui::GetIO().DisplaySize.y);
glClearColor(clear_color.x, clear_color.y, clear_color.z, clear_color.w);
glClear(GL_COLOR_BUFFER_BIT);
ImGui::Render();
SDL_GL_SwapWindow(window);
}
// Cleanup
ImGui_ImplSdlOgl3_Shutdown();
SDL_GL_DeleteContext(glcontext);
SDL_DestroyWindow(window);
SDL_Quit();
return 0;
}