Drezil/imgui
1
0
Fork 0
mirror of https://github.com/Drezil/imgui.git synced 2025-07-06 04:58:47 +02:00
Code Issues Packages Projects Releases Wiki Activity

Backends: moved global to a data structure to facilitate support for multi-contexts. (#586, #1851, #2004, #3012, #3934, #4141)

Browse Source 
This is NOT enable multi-contexts for any backends
- in order to make this commit as harmless as possible, while containing all the cruft/renaming
-
This commit is contained in:
ocornut
2021-06-28 16:52:10 +02:00
parent 88f4c1321a
commit 70c603854e
12 changed files with 1042 additions and 705 deletions
Download Patch File Download Diff File Expand all files Collapse all files

46
backends/imgui_impl_opengl2.cpp
View File

@ -19,6 +19,7 @@
// CHANGELOG
// (minor and older changes stripped away, please see git history for details)
// 2021-06-29: Reorganized backend to pull data from a single structure to facilitate usage with multiple-contexts (all g_XXXX access changed to bd->XXXX).
// 2021-05-19: OpenGL: Replaced direct access to ImDrawCmd::TextureId with a call to ImDrawCmd::GetTexID(). (will become a requirement)
// 2021-01-03: OpenGL: Backup, setup and restore GL_SHADE_MODEL state, disable GL_STENCIL_TEST and disable GL_NORMAL_ARRAY client state to increase compatibility with legacy OpenGL applications.
// 2020-01-23: OpenGL: Backup, setup and restore GL_TEXTURE_ENV to increase compatibility with legacy OpenGL applications.
@ -55,26 +56,47 @@
#include <GL/gl.h>
#endif
// OpenGL Data
static GLuint g_FontTexture = 0;
struct ImGui_ImplOpenGL2_Data
{
GLuint FontTexture;
ImGui_ImplOpenGL2_Data() { memset(this, 0, sizeof(*this)); }
};
// Wrapping access to backend data (to facilitate multiple-contexts stored in io.BackendPlatformUserData)
static ImGui_ImplOpenGL2_Data* g_Data;
static ImGui_ImplOpenGL2_Data* ImGui_ImplOpenGL2_CreateBackendData() { IM_ASSERT(g_Data == NULL); g_Data = IM_NEW(ImGui_ImplOpenGL2_Data); return g_Data; }
static ImGui_ImplOpenGL2_Data* ImGui_ImplOpenGL2_GetBackendData() { return ImGui::GetCurrentContext() != NULL ? g_Data : NULL; }
static void ImGui_ImplOpenGL2_DestroyBackendData() { IM_DELETE(g_Data); g_Data = NULL; }
// Functions
bool ImGui_ImplOpenGL2_Init()
{
// Setup backend capabilities flags
ImGuiIO& io = ImGui::GetIO();
IM_ASSERT(io.BackendRendererUserData == NULL && "Already initialized a renderer backend!");
// Setup backend capabilities flags
ImGui_ImplOpenGL2_Data* bd = ImGui_ImplOpenGL2_CreateBackendData();
io.BackendRendererUserData = (void*)bd;
io.BackendRendererName = "imgui_impl_opengl2";
return true;
}
void ImGui_ImplOpenGL2_Shutdown()
{
ImGuiIO& io = ImGui::GetIO();
ImGui_ImplOpenGL2_DestroyDeviceObjects();
io.BackendRendererName = NULL;
io.BackendRendererUserData = NULL;
ImGui_ImplOpenGL2_DestroyBackendData();
}
void ImGui_ImplOpenGL2_NewFrame()
{
if (!g_FontTexture)
ImGui_ImplOpenGL2_Data* bd = ImGui_ImplOpenGL2_GetBackendData();
if (!bd->FontTexture)
ImGui_ImplOpenGL2_CreateDeviceObjects();
}
@ -215,6 +237,7 @@ bool ImGui_ImplOpenGL2_CreateFontsTexture()
{
// Build texture atlas
ImGuiIO& io = ImGui::GetIO();
ImGui_ImplOpenGL2_Data* bd = ImGui_ImplOpenGL2_GetBackendData();
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.
@ -222,15 +245,15 @@ bool ImGui_ImplOpenGL2_CreateFontsTexture()
// 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);
glGenTextures(1, &bd->FontTexture);
glBindTexture(GL_TEXTURE_2D, bd->FontTexture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixels);
// Store our identifier
io.Fonts->SetTexID((ImTextureID)(intptr_t)g_FontTexture);
io.Fonts->SetTexID((ImTextureID)(intptr_t)bd->FontTexture);
// Restore state
glBindTexture(GL_TEXTURE_2D, last_texture);
@ -240,12 +263,13 @@ bool ImGui_ImplOpenGL2_CreateFontsTexture()
void ImGui_ImplOpenGL2_DestroyFontsTexture()
{
if (g_FontTexture)
ImGuiIO& io = ImGui::GetIO();
ImGui_ImplOpenGL2_Data* bd = ImGui_ImplOpenGL2_GetBackendData();
if (bd->FontTexture)
{
ImGuiIO& io = ImGui::GetIO();
glDeleteTextures(1, &g_FontTexture);
glDeleteTextures(1, &bd->FontTexture);
io.Fonts->SetTexID(0);
g_FontTexture = 0;
bd->FontTexture = 0;
}
}