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Examples: Refactored opengl3_exapmle into a glfw specific file that can be copied and pasted

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ocornut 2015-03-09 11:59:23 +00:00
parent 545a57d253
commit d829852391
7 changed files with 394 additions and 327 deletions
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344
examples/opengl3_example/imgui_impl_glfw_gl3.cpp Normal file
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// ImGui GLFW binding with OpenGL3 + shaders
// https://github.com/ocornut/imgui
#include <imgui.h>
#include "imgui_impl_glfw_gl3.h"
// GL3W/GLFW
#include <GL/gl3w.h>
#include <GLFW/glfw3.h>
#ifdef _MSC_VER
#undef APIENTRY
#define GLFW_EXPOSE_NATIVE_WIN32
#define GLFW_EXPOSE_NATIVE_WGL
#include <GLFW/glfw3native.h>
#endif
static GLFWwindow* GWindow = NULL;
static bool GMousePressed[3] = { false, false, false };
static float GMouseWheel = 0.0f;
static double GTime = 0.0f;
static bool GFontTextureLoaded = false;
// Shader variables
static int g_shader_handle = 0, g_vert_handle = 0, g_frag_handle = 0;
static int g_texture_location = 0, g_proj_mtx_location = 0;
static int g_position_location = 0, g_uv_location = 0, g_colour_location = 0;
static size_t g_vbo_max_size = 20000;
static unsigned int g_vbo_handle = 0, g_vao_handle = 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)
static void ImGui_ImplGlfwGL3_RenderDrawLists(ImDrawList** const cmd_lists, int cmd_lists_count)
{
if (cmd_lists_count == 0)
return;
// 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);
// Setup orthographic projection matrix
const float width = ImGui::GetIO().DisplaySize.x;
const float height = ImGui::GetIO().DisplaySize.y;
const float ortho_projection[4][4] =
{
{ 2.0f/width, 0.0f, 0.0f, 0.0f },
{ 0.0f, 2.0f/-height, 0.0f, 0.0f },
{ 0.0f, 0.0f, -1.0f, 0.0f },
{ -1.0f, 1.0f, 0.0f, 1.0f },
};
glUseProgram(g_shader_handle);
glUniform1i(g_texture_location, 0);
glUniformMatrix4fv(g_proj_mtx_location, 1, GL_FALSE, &ortho_projection[0][0]);
// Grow our buffer according to what we need
size_t total_vtx_count = 0;
for (int n = 0; n < cmd_lists_count; n++)
total_vtx_count += cmd_lists[n]->vtx_buffer.size();
glBindBuffer(GL_ARRAY_BUFFER, g_vbo_handle);
size_t neededBufferSize = total_vtx_count * sizeof(ImDrawVert);
if (neededBufferSize > g_vbo_max_size)
{
g_vbo_max_size = neededBufferSize + 5000; // Grow buffer
glBufferData(GL_ARRAY_BUFFER, g_vbo_max_size, NULL, GL_STREAM_DRAW);
}
// Copy and convert all vertices into a single contiguous buffer
unsigned char* buffer_data = (unsigned char*)glMapBuffer(GL_ARRAY_BUFFER, GL_WRITE_ONLY);
if (!buffer_data)
return;
for (int n = 0; n < cmd_lists_count; n++)
{
const ImDrawList* cmd_list = cmd_lists[n];
memcpy(buffer_data, &cmd_list->vtx_buffer[0], cmd_list->vtx_buffer.size() * sizeof(ImDrawVert));
buffer_data += cmd_list->vtx_buffer.size() * sizeof(ImDrawVert);
}
glUnmapBuffer(GL_ARRAY_BUFFER);
glBindBuffer(GL_ARRAY_BUFFER, 0);
glBindVertexArray(g_vao_handle);
int cmd_offset = 0;
for (int n = 0; n < cmd_lists_count; n++)
{
const ImDrawList* cmd_list = cmd_lists[n];
int vtx_offset = cmd_offset;
const ImDrawCmd* pcmd_end = cmd_list->commands.end();
for (const ImDrawCmd* pcmd = cmd_list->commands.begin(); pcmd != pcmd_end; pcmd++)
{
glBindTexture(GL_TEXTURE_2D, (GLuint)(intptr_t)pcmd->texture_id);
glScissor((int)pcmd->clip_rect.x, (int)(height - pcmd->clip_rect.w), (int)(pcmd->clip_rect.z - pcmd->clip_rect.x), (int)(pcmd->clip_rect.w - pcmd->clip_rect.y));
glDrawArrays(GL_TRIANGLES, vtx_offset, pcmd->vtx_count);
vtx_offset += pcmd->vtx_count;
}
cmd_offset = vtx_offset;
}
// Restore modified state
glBindVertexArray(0);
glUseProgram(0);
glDisable(GL_SCISSOR_TEST);
glBindTexture(GL_TEXTURE_2D, 0);
}
static const char* ImGui_ImplGlfwGL3_GetClipboardText()
{
return glfwGetClipboardString(GWindow);
}
static void ImGui_ImplGlfwGL3_SetClipboardText(const char* text)
{
glfwSetClipboardString(GWindow, text);
}
void ImGui_ImplGlfwGL3_MouseButtonCallback(GLFWwindow* window, int button, int action, int mods)
{
if (action == GLFW_PRESS && button >= 0 && button < 3)
GMousePressed[button] = true;
}
void ImGui_ImplGlfwGL3_ScrollCallback(GLFWwindow* window, double xoffset, double yoffset)
{
GMouseWheel += (float)yoffset; // Use fractional mouse wheel, 1.0 unit 5 lines.
}
void ImGui_ImplGlfwGL3_KeyCallback(GLFWwindow* window, int key, int scancode, int action, int mods)
{
ImGuiIO& io = ImGui::GetIO();
if (action == GLFW_PRESS)
io.KeysDown[key] = true;
if (action == GLFW_RELEASE)
io.KeysDown[key] = false;
io.KeyCtrl = (mods & GLFW_MOD_CONTROL) != 0;
io.KeyShift = (mods & GLFW_MOD_SHIFT) != 0;
}
void ImGui_ImplGlfwGL3_CharCallback(GLFWwindow* window, unsigned int c)
{
ImGuiIO& io = ImGui::GetIO();
if (c > 0 && c < 0x10000)
io.AddInputCharacter((unsigned short)c);
}
void ImGui_ImplGlfwGL3_LoadFontsTexture()
{
ImGuiIO& io = ImGui::GetIO();
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.
GLuint tex_id;
glGenTextures(1, &tex_id);
glBindTexture(GL_TEXTURE_2D, tex_id);
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)tex_id;
GFontTextureLoaded = true;
}
static void InitGL()
{
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_shader_handle = glCreateProgram();
g_vert_handle = glCreateShader(GL_VERTEX_SHADER);
g_frag_handle = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource(g_vert_handle, 1, &vertex_shader, 0);
glShaderSource(g_frag_handle, 1, &fragment_shader, 0);
glCompileShader(g_vert_handle);
glCompileShader(g_frag_handle);
glAttachShader(g_shader_handle, g_vert_handle);
glAttachShader(g_shader_handle, g_frag_handle);
glLinkProgram(g_shader_handle);
g_texture_location = glGetUniformLocation(g_shader_handle, "Texture");
g_proj_mtx_location = glGetUniformLocation(g_shader_handle, "ProjMtx");
g_position_location = glGetAttribLocation(g_shader_handle, "Position");
g_uv_location = glGetAttribLocation(g_shader_handle, "UV");
g_colour_location = glGetAttribLocation(g_shader_handle, "Color");
glGenBuffers(1, &g_vbo_handle);
glBindBuffer(GL_ARRAY_BUFFER, g_vbo_handle);
glBufferData(GL_ARRAY_BUFFER, g_vbo_max_size, NULL, GL_DYNAMIC_DRAW);
glGenVertexArrays(1, &g_vao_handle);
glBindVertexArray(g_vao_handle);
glBindBuffer(GL_ARRAY_BUFFER, g_vbo_handle);
glEnableVertexAttribArray(g_position_location);
glEnableVertexAttribArray(g_uv_location);
glEnableVertexAttribArray(g_colour_location);
#define OFFSETOF(TYPE, ELEMENT) ((size_t)&(((TYPE *)0)->ELEMENT))
glVertexAttribPointer(g_position_location, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)OFFSETOF(ImDrawVert, pos));
glVertexAttribPointer(g_uv_location, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)OFFSETOF(ImDrawVert, uv));
glVertexAttribPointer(g_colour_location, 4, GL_UNSIGNED_BYTE, GL_TRUE, sizeof(ImDrawVert), (GLvoid*)OFFSETOF(ImDrawVert, col));
#undef OFFSETOF
glBindVertexArray(0);
glBindBuffer(GL_ARRAY_BUFFER, 0);
}
bool ImGui_ImplGlfwGL3_Init(GLFWwindow* window, bool install_callbacks)
{
InitGL();
GWindow = window;
ImGuiIO& io = ImGui::GetIO();
io.KeyMap[ImGuiKey_Tab] = GLFW_KEY_TAB; // Keyboard mapping. ImGui will use those indices to peek into the io.KeyDown[] array.
io.KeyMap[ImGuiKey_LeftArrow] = GLFW_KEY_LEFT;
io.KeyMap[ImGuiKey_RightArrow] = GLFW_KEY_RIGHT;
io.KeyMap[ImGuiKey_UpArrow] = GLFW_KEY_UP;
io.KeyMap[ImGuiKey_DownArrow] = GLFW_KEY_DOWN;
io.KeyMap[ImGuiKey_Home] = GLFW_KEY_HOME;
io.KeyMap[ImGuiKey_End] = GLFW_KEY_END;
io.KeyMap[ImGuiKey_Delete] = GLFW_KEY_DELETE;
io.KeyMap[ImGuiKey_Backspace] = GLFW_KEY_BACKSPACE;
io.KeyMap[ImGuiKey_Enter] = GLFW_KEY_ENTER;
io.KeyMap[ImGuiKey_Escape] = GLFW_KEY_ESCAPE;
io.KeyMap[ImGuiKey_A] = GLFW_KEY_A;
io.KeyMap[ImGuiKey_C] = GLFW_KEY_C;
io.KeyMap[ImGuiKey_V] = GLFW_KEY_V;
io.KeyMap[ImGuiKey_X] = GLFW_KEY_X;
io.KeyMap[ImGuiKey_Y] = GLFW_KEY_Y;
io.KeyMap[ImGuiKey_Z] = GLFW_KEY_Z;
io.RenderDrawListsFn = ImGui_ImplGlfwGL3_RenderDrawLists;
io.SetClipboardTextFn = ImGui_ImplGlfwGL3_SetClipboardText;
io.GetClipboardTextFn = ImGui_ImplGlfwGL3_GetClipboardText;
#ifdef _MSC_VER
io.ImeWindowHandle = glfwGetWin32Window(GWindow);
#endif
if (install_callbacks)
{
glfwSetMouseButtonCallback(window, ImGui_ImplGlfwGL3_MouseButtonCallback);
glfwSetScrollCallback(window, ImGui_ImplGlfwGL3_ScrollCallback);
glfwSetKeyCallback(window, ImGui_ImplGlfwGL3_KeyCallback);
glfwSetCharCallback(window, ImGui_ImplGlfwGL3_CharCallback);
}
return true;
}
void ImGui_ImplGlfwGL3_Shutdown()
{
if (g_vao_handle) glDeleteVertexArrays(1, &g_vao_handle);
if (g_vbo_handle) glDeleteBuffers(1, &g_vbo_handle);
g_vao_handle = 0;
g_vbo_handle = 0;
glDetachShader(g_shader_handle, g_vert_handle);
glDeleteShader(g_vert_handle);
g_vert_handle = 0;
glDetachShader(g_shader_handle, g_frag_handle);
glDeleteShader(g_frag_handle);
g_frag_handle = 0;
glDeleteProgram(g_shader_handle);
g_shader_handle = 0;
GLuint tex_id = (GLuint)ImGui::GetIO().Fonts->TexID;
if (tex_id)
{
glDeleteTextures(1, &tex_id);
ImGui::GetIO().Fonts->TexID = 0;
}
ImGui::Shutdown();
}
void ImGui_ImplGlfwGL3_NewFrame()
{
if (!GFontTextureLoaded)
ImGui_ImplGlfwGL3_LoadFontsTexture();
ImGuiIO& io = ImGui::GetIO();
// Setup display size (every frame to accommodate for window resizing)
int w, h;
int display_w, display_h;
glfwGetWindowSize(GWindow, &w, &h);
glfwGetFramebufferSize(GWindow, &display_w, &display_h);
io.DisplaySize = ImVec2((float)display_w, (float)display_h);
// Setup time step
double current_time = glfwGetTime();
io.DeltaTime = GTime > 0.0 ? (float)(current_time - GTime) : (float)(1.0f/60.0f);
GTime = current_time;
// Setup inputs
// (we already got mouse wheel, keyboard keys & characters from glfw callbacks polled in glfwPollEvents())
double mouse_x, mouse_y;
glfwGetCursorPos(GWindow, &mouse_x, &mouse_y);
mouse_x *= (float)display_w / w; // Convert mouse coordinates to pixels
mouse_y *= (float)display_h / h;
io.MousePos = ImVec2((float)mouse_x, (float)mouse_y); // Mouse position, in pixels (set to -1,-1 if no mouse / on another screen, etc.)
io.MouseDown[0] = GMousePressed[0] || glfwGetMouseButton(GWindow, GLFW_MOUSE_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] = GMousePressed[1] || glfwGetMouseButton(GWindow, GLFW_MOUSE_BUTTON_RIGHT) != 0;
io.MouseDown[2] = GMousePressed[2] || glfwGetMouseButton(GWindow, GLFW_MOUSE_BUTTON_MIDDLE) != 0;
GMousePressed[0] = false;
GMousePressed[1] = false;
GMousePressed[2] = false;
io.MouseWheel = GMouseWheel;
GMouseWheel = 0.0f;
// Start the frame
ImGui::NewFrame();
}

16
examples/opengl3_example/imgui_impl_glfw_gl3.h Normal file
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@ -0,0 +1,16 @@
// ImGui GLFW binding with OpenGL3 + shaders
// https://github.com/ocornut/imgui
struct GLFWwindow;
bool ImGui_ImplGlfwGL3_Init(GLFWwindow* window, bool install_callbacks);
void ImGui_ImplGlfwGL3_Shutdown();
void ImGui_ImplGlfwGL3_LoadFontsTexture();
void ImGui_ImplGlfwGL3_NewFrame();
// GLFW callbacks (installed by default if you enable 'install_callbacks' during initialization)
// Provide here if you want to chain callbacks
void ImGui_ImplGlfwGL3_MouseButtonCallback(GLFWwindow* window, int button, int action, int mods);
void ImGui_ImplGlfwGL3_ScrollCallback(GLFWwindow* window, double xoffset, double yoffset);
void ImGui_ImplGlFwGL3_KeyCallback(GLFWwindow* window, int key, int scancode, int action, int mods);
void ImGui_ImplGlfwGL3_CharCallback(GLFWwindow* window, unsigned int c);

338
examples/opengl3_example/main.cpp
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@ -1,165 +1,19 @@
// ImGui - standalone example application for OpenGL 3, using programmable pipeline
// ImGui - standalone example application for Glfw + OpenGL 3, using programmable pipeline
#ifdef _MSC_VER
#pragma warning (disable: 4996) // 'This function or variable may be unsafe': strcpy, strdup, sprintf, vsnprintf, sscanf, fopen
#endif
#ifdef __clang__
#pragma clang diagnostic ignored "-Wunused-function" // warning: unused function
#endif
#include "../../imgui.h"
#include <imgui.h>
#include "imgui_impl_glfw_GL3.h"
#include <stdio.h>
// Gl3W / GLFW
#include <GL/gl3w.h>
#include <GLFW/glfw3.h>
#ifdef _MSC_VER
#undef APIENTRY
#define GLFW_EXPOSE_NATIVE_WIN32
#define GLFW_EXPOSE_NATIVE_WGL
#include <GLFW/glfw3native.h>
#endif
static GLFWwindow* window;
static bool mousePressed[2] = { false, false };
#define OFFSETOF(TYPE, ELEMENT) ((size_t)&(((TYPE *)0)->ELEMENT))
// Shader variables
static int shader_handle, vert_handle, frag_handle;
static int texture_location, proj_mtx_location;
static int position_location, uv_location, colour_location;
static size_t vbo_max_size = 20000;
static unsigned int vbo_handle, vao_handle;
// 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)
static void ImImpl_RenderDrawLists(ImDrawList** const cmd_lists, int cmd_lists_count)
static void error_callback(int error, const char* description)
{
if (cmd_lists_count == 0)
return;
// 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);
// Setup orthographic projection matrix
const float width = ImGui::GetIO().DisplaySize.x;
const float height = ImGui::GetIO().DisplaySize.y;
const float ortho_projection[4][4] =
{
{ 2.0f/width, 0.0f, 0.0f, 0.0f },
{ 0.0f, 2.0f/-height, 0.0f, 0.0f },
{ 0.0f, 0.0f, -1.0f, 0.0f },
{ -1.0f, 1.0f, 0.0f, 1.0f },
};
glUseProgram(shader_handle);
glUniform1i(texture_location, 0);
glUniformMatrix4fv(proj_mtx_location, 1, GL_FALSE, &ortho_projection[0][0]);
// Grow our buffer according to what we need
size_t total_vtx_count = 0;
for (int n = 0; n < cmd_lists_count; n++)
total_vtx_count += cmd_lists[n]->vtx_buffer.size();
glBindBuffer(GL_ARRAY_BUFFER, vbo_handle);
size_t neededBufferSize = total_vtx_count * sizeof(ImDrawVert);
if (neededBufferSize > vbo_max_size)
{
vbo_max_size = neededBufferSize + 5000; // Grow buffer
glBufferData(GL_ARRAY_BUFFER, vbo_max_size, NULL, GL_STREAM_DRAW);
}
// Copy and convert all vertices into a single contiguous buffer
unsigned char* buffer_data = (unsigned char*)glMapBuffer(GL_ARRAY_BUFFER, GL_WRITE_ONLY);
if (!buffer_data)
return;
for (int n = 0; n < cmd_lists_count; n++)
{
const ImDrawList* cmd_list = cmd_lists[n];
memcpy(buffer_data, &cmd_list->vtx_buffer[0], cmd_list->vtx_buffer.size() * sizeof(ImDrawVert));
buffer_data += cmd_list->vtx_buffer.size() * sizeof(ImDrawVert);
}
glUnmapBuffer(GL_ARRAY_BUFFER);
glBindBuffer(GL_ARRAY_BUFFER, 0);
glBindVertexArray(vao_handle);
int cmd_offset = 0;
for (int n = 0; n < cmd_lists_count; n++)
{
const ImDrawList* cmd_list = cmd_lists[n];
int vtx_offset = cmd_offset;
const ImDrawCmd* pcmd_end = cmd_list->commands.end();
for (const ImDrawCmd* pcmd = cmd_list->commands.begin(); pcmd != pcmd_end; pcmd++)
{
glBindTexture(GL_TEXTURE_2D, (GLuint)(intptr_t)pcmd->texture_id);
glScissor((int)pcmd->clip_rect.x, (int)(height - pcmd->clip_rect.w), (int)(pcmd->clip_rect.z - pcmd->clip_rect.x), (int)(pcmd->clip_rect.w - pcmd->clip_rect.y));
glDrawArrays(GL_TRIANGLES, vtx_offset, pcmd->vtx_count);
vtx_offset += pcmd->vtx_count;
}
cmd_offset = vtx_offset;
}
// Restore modified state
glBindVertexArray(0);
glUseProgram(0);
glDisable(GL_SCISSOR_TEST);
glBindTexture(GL_TEXTURE_2D, 0);
fprintf(stderr, "Error: %s\n", description);
}
static const char* ImImpl_GetClipboardTextFn()
int main(int argc, char** argv)
{
return glfwGetClipboardString(window);
}
static void ImImpl_SetClipboardTextFn(const char* text)
{
glfwSetClipboardString(window, text);
}
// GLFW callbacks to get events
static void glfw_error_callback(int error, const char* description)
{
fputs(description, stderr);
}
static void glfw_mouse_button_callback(GLFWwindow* window, int button, int action, int mods)
{
if (action == GLFW_PRESS && button >= 0 && button < 2)
mousePressed[button] = true;
}
static void glfw_scroll_callback(GLFWwindow* window, double xoffset, double yoffset)
{
ImGuiIO& io = ImGui::GetIO();
io.MouseWheel += (float)yoffset; // Use fractional mouse wheel, 1.0 unit 5 lines.
}
static void glfw_key_callback(GLFWwindow* window, int key, int scancode, int action, int mods)
{
ImGuiIO& io = ImGui::GetIO();
if (action == GLFW_PRESS)
io.KeysDown[key] = true;
if (action == GLFW_RELEASE)
io.KeysDown[key] = false;
io.KeyCtrl = (mods & GLFW_MOD_CONTROL) != 0;
io.KeyShift = (mods & GLFW_MOD_SHIFT) != 0;
}
static void glfw_char_callback(GLFWwindow* window, unsigned int c)
{
if (c > 0 && c < 0x10000)
ImGui::GetIO().AddInputCharacter((unsigned short)c);
}
void InitGL()
{
glfwSetErrorCallback(glfw_error_callback);
glfwSetErrorCallback(error_callback);
if (!glfwInit())
exit(1);
@ -167,180 +21,28 @@ void InitGL()
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
window = glfwCreateWindow(1280, 720, "ImGui OpenGL3 example", NULL, NULL);
GLFWwindow* window = glfwCreateWindow(1280, 720, "ImGui OpenGL3 example", NULL, NULL);
glfwMakeContextCurrent(window);
glfwSetKeyCallback(window, glfw_key_callback);
glfwSetMouseButtonCallback(window, glfw_mouse_button_callback);
glfwSetScrollCallback(window, glfw_scroll_callback);
glfwSetCharCallback(window, glfw_char_callback);
gl3wInit();
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";
shader_handle = glCreateProgram();
vert_handle = glCreateShader(GL_VERTEX_SHADER);
frag_handle = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource(vert_handle, 1, &vertex_shader, 0);
glShaderSource(frag_handle, 1, &fragment_shader, 0);
glCompileShader(vert_handle);
glCompileShader(frag_handle);
glAttachShader(shader_handle, vert_handle);
glAttachShader(shader_handle, frag_handle);
glLinkProgram(shader_handle);
texture_location = glGetUniformLocation(shader_handle, "Texture");
proj_mtx_location = glGetUniformLocation(shader_handle, "ProjMtx");
position_location = glGetAttribLocation(shader_handle, "Position");
uv_location = glGetAttribLocation(shader_handle, "UV");
colour_location = glGetAttribLocation(shader_handle, "Color");
glGenBuffers(1, &vbo_handle);
glBindBuffer(GL_ARRAY_BUFFER, vbo_handle);
glBufferData(GL_ARRAY_BUFFER, vbo_max_size, NULL, GL_DYNAMIC_DRAW);
glGenVertexArrays(1, &vao_handle);
glBindVertexArray(vao_handle);
glBindBuffer(GL_ARRAY_BUFFER, vbo_handle);
glEnableVertexAttribArray(position_location);
glEnableVertexAttribArray(uv_location);
glEnableVertexAttribArray(colour_location);
glVertexAttribPointer(position_location, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)OFFSETOF(ImDrawVert, pos));
glVertexAttribPointer(uv_location, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)OFFSETOF(ImDrawVert, uv));
glVertexAttribPointer(colour_location, 4, GL_UNSIGNED_BYTE, GL_TRUE, sizeof(ImDrawVert), (GLvoid*)OFFSETOF(ImDrawVert, col));
glBindVertexArray(0);
glBindBuffer(GL_ARRAY_BUFFER, 0);
}
void LoadFontsTexture()
{
ImGuiIO& io = ImGui::GetIO();
//ImGuiIO& io = ImGui::GetIO();
//ImFont* my_font1 = io.Fonts->AddFontDefault();
//ImFont* my_font2 = io.Fonts->AddFontFromFileTTF("extra_fonts/Karla-Regular.ttf", 15.0f);
//ImFont* my_font3 = io.Fonts->AddFontFromFileTTF("extra_fonts/ProggyClean.ttf", 13.0f); my_font3->DisplayOffset.y += 1;
//ImFont* my_font4 = io.Fonts->AddFontFromFileTTF("extra_fonts/ProggyTiny.ttf", 10.0f); my_font4->DisplayOffset.y += 1;
//ImFont* my_font5 = io.Fonts->AddFontFromFileTTF("c:\\Windows\\Fonts\\ArialUni.ttf", 18.0f, io.Fonts->GetGlyphRangesJapanese());
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.
GLuint tex_id;
glGenTextures(1, &tex_id);
glBindTexture(GL_TEXTURE_2D, tex_id);
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)tex_id;
}
void InitImGui()
{
ImGuiIO& io = ImGui::GetIO();
io.DeltaTime = 1.0f / 60.0f; // Time elapsed since last frame, in seconds (in this sample app we'll override this every frame because our timestep is variable)
io.KeyMap[ImGuiKey_Tab] = GLFW_KEY_TAB; // Keyboard mapping. ImGui will use those indices to peek into the io.KeyDown[] array.
io.KeyMap[ImGuiKey_LeftArrow] = GLFW_KEY_LEFT;
io.KeyMap[ImGuiKey_RightArrow] = GLFW_KEY_RIGHT;
io.KeyMap[ImGuiKey_UpArrow] = GLFW_KEY_UP;
io.KeyMap[ImGuiKey_DownArrow] = GLFW_KEY_DOWN;
io.KeyMap[ImGuiKey_Home] = GLFW_KEY_HOME;
io.KeyMap[ImGuiKey_End] = GLFW_KEY_END;
io.KeyMap[ImGuiKey_Delete] = GLFW_KEY_DELETE;
io.KeyMap[ImGuiKey_Backspace] = GLFW_KEY_BACKSPACE;
io.KeyMap[ImGuiKey_Enter] = GLFW_KEY_ENTER;
io.KeyMap[ImGuiKey_Escape] = GLFW_KEY_ESCAPE;
io.KeyMap[ImGuiKey_A] = GLFW_KEY_A;
io.KeyMap[ImGuiKey_C] = GLFW_KEY_C;
io.KeyMap[ImGuiKey_V] = GLFW_KEY_V;
io.KeyMap[ImGuiKey_X] = GLFW_KEY_X;
io.KeyMap[ImGuiKey_Y] = GLFW_KEY_Y;
io.KeyMap[ImGuiKey_Z] = GLFW_KEY_Z;
io.RenderDrawListsFn = ImImpl_RenderDrawLists;
io.SetClipboardTextFn = ImImpl_SetClipboardTextFn;
io.GetClipboardTextFn = ImImpl_GetClipboardTextFn;
#ifdef _MSC_VER
io.ImeWindowHandle = glfwGetWin32Window(window);
#endif
LoadFontsTexture();
}
void UpdateImGui()
{
ImGuiIO& io = ImGui::GetIO();
// Setup resolution (every frame to accommodate for window resizing)
int w, h;
int display_w, display_h;
glfwGetWindowSize(window, &w, &h);
glfwGetFramebufferSize(window, &display_w, &display_h);
io.DisplaySize = ImVec2((float)display_w, (float)display_h); // Display size, in pixels. For clamping windows positions.
// Setup time step
static double time = 0.0f;
const double current_time = glfwGetTime();
io.DeltaTime = (float)(current_time - time);
time = current_time;
// Setup inputs
// (we already got mouse wheel, keyboard keys & characters from glfw callbacks polled in glfwPollEvents())
double mouse_x, mouse_y;
glfwGetCursorPos(window, &mouse_x, &mouse_y);
mouse_x *= (float)display_w / w; // Convert mouse coordinates to pixels
mouse_y *= (float)display_h / h;
io.MousePos = ImVec2((float)mouse_x, (float)mouse_y); // Mouse position, in pixels (set to -1,-1 if no mouse / on another screen, etc.)
io.MouseDown[0] = mousePressed[0] || glfwGetMouseButton(window, GLFW_MOUSE_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] = mousePressed[1] || glfwGetMouseButton(window, GLFW_MOUSE_BUTTON_RIGHT) != 0;
// Start the frame
ImGui::NewFrame();
}
// Application code
int main(int argc, char** argv)
{
InitGL();
InitImGui();
ImGui_ImplGlfwGL3_Init(window, true);
ImGui_ImplGlfwGL3_LoadFontsTexture();
bool show_test_window = true;
bool show_another_window = false;
ImVec4 clear_col = ImColor(114, 144, 154);
ImVec4 clear_color = ImColor(114, 144, 154);
while (!glfwWindowShouldClose(window))
{
ImGuiIO& io = ImGui::GetIO();
io.MouseWheel = 0;
mousePressed[0] = mousePressed[1] = false;
glfwPollEvents();
UpdateImGui();
ImGui_ImplGlfwGL3_NewFrame();
// 1. Show a simple window
// Tip: if we don't call ImGui::Begin()/ImGui::End() the widgets appears in a window automatically called "Debug"
@ -348,7 +50,7 @@ int main(int argc, char** argv)
static float f;
ImGui::Text("Hello, world!");
ImGui::SliderFloat("float", &f, 0.0f, 1.0f);
ImGui::ColorEdit3("clear color", (float*)&clear_col);
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);
@ -371,22 +73,14 @@ int main(int argc, char** argv)
// Rendering
glViewport(0, 0, (int)io.DisplaySize.x, (int)io.DisplaySize.y);
glClearColor(clear_col.x, clear_col.y, clear_col.z, clear_col.w);
glClearColor(clear_color.x, clear_color.y, clear_color.z, clear_color.w);
glClear(GL_COLOR_BUFFER_BIT);
ImGui::Render();
glfwSwapBuffers(window);
}
// Cleanup
if (vao_handle) glDeleteVertexArrays(1, &vao_handle);
if (vbo_handle) glDeleteBuffers(1, &vbo_handle);
glDetachShader(shader_handle, vert_handle);
glDetachShader(shader_handle, frag_handle);
glDeleteShader(vert_handle);
glDeleteShader(frag_handle);
glDeleteProgram(shader_handle);
ImGui::Shutdown();
ImGui_ImplGlfwGL3_Shutdown();
glfwTerminate();
return 0;

4
examples/opengl3_example/opengl3_example.vcxproj
View File

@ -39,10 +39,12 @@
<PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
<OutDir>$(ProjectDir)$(Configuration)\</OutDir>
<IntDir>$(ProjectDir)$(Configuration)\</IntDir>
<IncludePath>../..;$(IncludePath)</IncludePath>
</PropertyGroup>
<PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
<OutDir>$(ProjectDir)$(Configuration)\</OutDir>
<IntDir>$(ProjectDir)$(Configuration)\</IntDir>
<IncludePath>../..;$(IncludePath)</IncludePath>
</PropertyGroup>
<ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
<ClCompile>
@ -80,11 +82,13 @@
<ItemGroup>
<ClCompile Include="..\..\imgui.cpp" />
<ClCompile Include="..\opengl_example\gl3w\GL\gl3w.c" />
<ClCompile Include="imgui_impl_glfw_gl3.cpp" />
<ClCompile Include="main.cpp" />
</ItemGroup>
<ItemGroup>
<ClInclude Include="..\..\imconfig.h" />
<ClInclude Include="..\..\imgui.h" />
<ClInclude Include="imgui_impl_glfw_gl3.h" />
</ItemGroup>
<Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
<ImportGroup Label="ExtensionTargets">

6
examples/opengl3_example/opengl3_example.vcxproj.filters
View File

@ -19,6 +19,9 @@
<ClCompile Include="..\opengl_example\gl3w\GL\gl3w.c">
<Filter>sources</Filter>
</ClCompile>
<ClCompile Include="imgui_impl_glfw_gl3.cpp">
<Filter>sources</Filter>
</ClCompile>
</ItemGroup>
<ItemGroup>
<ClInclude Include="..\..\imconfig.h">
@ -27,5 +30,8 @@
<ClInclude Include="..\..\imgui.h">
<Filter>imgui</Filter>
</ClInclude>
<ClInclude Include="imgui_impl_glfw_gl3.h">
<Filter>sources</Filter>
</ClInclude>
</ItemGroup>
</Project>

11
examples/opengl_example/imgui_impl_glfw.cpp
View File

@ -1,4 +1,4 @@
// ImGui GLFW bindings
// ImGui GLFW binding with OpenGL
// https://github.com/ocornut/imgui
#include <imgui.h>
@ -15,8 +15,9 @@
static GLFWwindow* GWindow = NULL;
static bool GMousePressed[3] = { false, false, false };
static float GMouseWheel = 0.0f;
static double GTime = 0.0f;
static bool GFontTextureLoaded;
static bool GFontTextureLoaded = false;
// 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:
@ -102,8 +103,7 @@ void ImGui_ImplGlfw_MouseButtonCallback(GLFWwindow* window, int button, int acti
void ImGui_ImplGlfw_ScrollCallback(GLFWwindow* window, double xoffset, double yoffset)
{
ImGuiIO& io = ImGui::GetIO();
io.MouseWheel += (float)yoffset; // Use fractional mouse wheel, 1.0 unit 5 lines.
GMouseWheel += (float)yoffset; // Use fractional mouse wheel, 1.0 unit 5 lines.
}
void ImGui_ImplGlFw_KeyCallback(GLFWwindow* window, int key, int scancode, int action, int mods)
@ -231,6 +231,9 @@ void ImGui_ImplGlfw_NewFrame()
GMousePressed[1] = false;
GMousePressed[2] = false;
io.MouseWheel = GMouseWheel;
GMouseWheel = 0.0f;
// Start the frame
ImGui::NewFrame();
}

2
examples/opengl_example/imgui_impl_glfw.h
View File

@ -1,4 +1,4 @@
// ImGui GLFW bindings
// ImGui GLFW binding with OpenGL
// https://github.com/ocornut/imgui
struct GLFWwindow;