Examples: OpenGL2: Added (yet another) comment/instruction against using opengl2 with modern OpenGL. (#2297)
diff --git a/examples/example_glfw_opengl2/main.cpp b/examples/example_glfw_opengl2/main.cpp
index f12547b..eae7ed7 100644
--- a/examples/example_glfw_opengl2/main.cpp
+++ b/examples/example_glfw_opengl2/main.cpp
@@ -129,8 +129,14 @@
glViewport(0, 0, display_w, display_h);
glClearColor(clear_color.x, clear_color.y, clear_color.z, clear_color.w);
glClear(GL_COLOR_BUFFER_BIT);
- //glUseProgram(0); // You may want this if using this code in an OpenGL 3+ context where shaders may be bound, but prefer using the GL3+ code.
+
+ // If you are using this code with non-legacy OpenGL header/contexts (which you should not, prefer using imgui_impl_opengl3.cpp!!),
+ // you may need to backup/reset/restore current shader using the commented lines below.
+ //GLint last_program;
+ //glGetIntegerv(GL_CURRENT_PROGRAM, &last_program);
+ //glUseProgram(0);
ImGui_ImplOpenGL2_RenderDrawData(ImGui::GetDrawData());
+ //glUseProgram(last_program);
glfwMakeContextCurrent(window);
glfwSwapBuffers(window);
diff --git a/examples/imgui_impl_opengl2.cpp b/examples/imgui_impl_opengl2.cpp
index 057f853..9745238 100644
--- a/examples/imgui_impl_opengl2.cpp
+++ b/examples/imgui_impl_opengl2.cpp
@@ -102,7 +102,14 @@
glEnableClientState(GL_COLOR_ARRAY);
glEnable(GL_TEXTURE_2D);
glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
- //glUseProgram(0); // You may want this if using this code in an OpenGL 3+ context where shaders may be bound
+
+ // If you are using this code with non-legacy OpenGL header/contexts (which you should not, prefer using imgui_impl_opengl3.cpp!!),
+ // you may need to backup/reset/restore current shader using the lines below. DO NOT MODIFY THIS FILE! Add the code in your calling function:
+ // GLint last_program;
+ // glGetIntegerv(GL_CURRENT_PROGRAM, &last_program);
+ // glUseProgram(0);
+ // ImGui_ImplOpenGL2_RenderDrawData(...);
+ // glUseProgram(last_program)
// Setup viewport, orthographic projection matrix
// Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right). DisplayMin is typically (0,0) for single viewport apps.
