Backends: OpenGL3: Fixed loader compatibility with GL_VERSION for GL 2.x (#6154, #4445, #3530)
GL_MAJOR_VERSION and GL_MINOR_VERSION are available on GL 3.0 and above.
So we have to parse GL_VERSION under GL 2.x
Reference https://www.khronos.org/opengl/wiki/OpenGL_Context#Context_information_queries
Regressed since 459de65477423360176447e79df2f3a785b71f3d
See https://github.com/ocornut/imgui/pull/3530
diff --git a/backends/imgui_impl_opengl3_loader.h b/backends/imgui_impl_opengl3_loader.h
index 5b6615e..2ebb2cf 100644
--- a/backends/imgui_impl_opengl3_loader.h
+++ b/backends/imgui_impl_opengl3_loader.h
@@ -685,7 +685,13 @@
return GL3W_ERROR_INIT;
glGetIntegerv(GL_MAJOR_VERSION, &version.major);
glGetIntegerv(GL_MINOR_VERSION, &version.minor);
- if (version.major < 3)
+ if (version.major == 0 && version.minor == 0)
+ {
+ // Query GL_VERSION in desktop GL 2.x, the string will start with "<major>.<minor>"
+ const char* gl_version = (const char*)glGetString(GL_VERSION);
+ sscanf(gl_version, "%d.%d", &version.major, &version.minor);
+ }
+ if (version.major < 2)
return GL3W_ERROR_OPENGL_VERSION;
return GL3W_OK;
}
@@ -709,7 +715,7 @@
int imgl3wIsSupported(int major, int minor)
{
- if (major < 3)
+ if (major < 2)
return 0;
if (version.major == major)
return version.minor >= minor;
diff --git a/docs/CHANGELOG.txt b/docs/CHANGELOG.txt
index bb0bf57..fb9df81 100644
--- a/docs/CHANGELOG.txt
+++ b/docs/CHANGELOG.txt
@@ -116,7 +116,8 @@
- Backends: GLFW: Added ImGui_ImplGlfw_SetCallbacksChainForAllWindows() to instruct backend
to chain callbacks even for secondary viewports/windows. User callbacks may need to test
the 'window' parameter. (#6142)
-- Backends: WebGPU: Fix building for latest WebGPU specs (remove implicit layout generation).
+- Backends: OpenGL3: Fixed GL loader compatibility with 2.x profiles. (#6154, #4445, #3530) [@grauw]
+- Backends: WebGPU: Fixed building for latest WebGPU specs (remove implicit layout generation).
(#6117, #4116, #3632) [@tonygrue, @bfierz]
- Examples: refactored SDL2+GL and GLFW+GL examples to compile with Emscripten.
(#2492, #2494, #3699, #3705) [@ocornut, @nicolasnoble]
