Examples: OpenGL: Added a dummy GL call + comments in ImGui_ImplOpenGL3_Init() to detect uninitialized GL function loaders early, and help users understand what they are missing. (#2421)
diff --git a/docs/CHANGELOG.txt b/docs/CHANGELOG.txt
index 69de4fd..13dd38e 100644
--- a/docs/CHANGELOG.txt
+++ b/docs/CHANGELOG.txt
@@ -36,6 +36,8 @@
Breaking Changes:
Other Changes:
+- Examples: OpenGL: Added a dummy GL call + comments in ImGui_ImplOpenGL3_Init() to detect uninitialized
+ GL function loaders early, and help users understand what they are missing. (#2421)
-----------------------------------------------------------------------
diff --git a/examples/imgui_impl_opengl3.cpp b/examples/imgui_impl_opengl3.cpp
index 84b8777..9890436 100644
--- a/examples/imgui_impl_opengl3.cpp
+++ b/examples/imgui_impl_opengl3.cpp
@@ -12,6 +12,7 @@
// CHANGELOG
// (minor and older changes stripped away, please see git history for details)
+// 2019-03-15: OpenGL: Added a dummy GL call + comments in ImGui_ImplOpenGL3_Init() to detect uninitialized GL function loaders early.
// 2019-03-03: OpenGL: Fix support for ES 2.0 (WebGL 1.0).
// 2019-02-20: OpenGL: Fix for OSX not supporting OpenGL 4.5, we don't try to read GL_CLIP_ORIGIN even if defined by the headers/loader.
// 2019-02-11: OpenGL: Projecting clipping rectangles correctly using draw_data->FramebufferScale to allow multi-viewports for retina display.
@@ -89,11 +90,11 @@
// Helper libraries are often used for this purpose! Here we are supporting a few common ones (gl3w, glew, glad).
// You may use another loader/header of your choice (glext, glLoadGen, etc.), or chose to manually implement your own.
#if defined(IMGUI_IMPL_OPENGL_LOADER_GL3W)
-#include <GL/gl3w.h>
+#include <GL/gl3w.h> // Needs to be initialized with gl3wInit() in user's code
#elif defined(IMGUI_IMPL_OPENGL_LOADER_GLEW)
-#include <GL/glew.h>
+#include <GL/glew.h> // Needs to be initialized with glewInit() in user's code
#elif defined(IMGUI_IMPL_OPENGL_LOADER_GLAD)
-#include <glad/glad.h>
+#include <glad/glad.h> // Needs to be initialized with gladLoadGL() in user's code
#else
#include IMGUI_IMPL_OPENGL_LOADER_CUSTOM
#endif
@@ -128,6 +129,12 @@
strcpy(g_GlslVersionString, glsl_version);
strcat(g_GlslVersionString, "\n");
+ // Make a dummy GL call (we don't actually need the result)
+ // IF YOU GET A CRASH HERE: it probably means that you haven't initialized the OpenGL function loader used by this code.
+ // Desktop OpenGL 3/4 need a function loader. See the IMGUI_IMPL_OPENGL_LOADER_xxx explanation above.
+ GLint current_texture;
+ glGetIntegerv(GL_TEXTURE_BINDING_2D, ¤t_texture);
+
return true;
}
diff --git a/imgui_demo.cpp b/imgui_demo.cpp
index ce99dde..c937da4 100644
--- a/imgui_demo.cpp
+++ b/imgui_demo.cpp
@@ -2565,9 +2565,9 @@
ImGui::Text("Mouse released:"); for (int i = 0; i < IM_ARRAYSIZE(io.MouseDown); i++) if (ImGui::IsMouseReleased(i)) { ImGui::SameLine(); ImGui::Text("b%d", i); }
ImGui::Text("Mouse wheel: %.1f", io.MouseWheel);
- ImGui::Text("Keys down:"); for (int i = 0; i < IM_ARRAYSIZE(io.KeysDown); i++) if (io.KeysDownDuration[i] >= 0.0f) { ImGui::SameLine(); ImGui::Text("%d (%.02f secs)", i, io.KeysDownDuration[i]); }
- ImGui::Text("Keys pressed:"); for (int i = 0; i < IM_ARRAYSIZE(io.KeysDown); i++) if (ImGui::IsKeyPressed(i)) { ImGui::SameLine(); ImGui::Text("%d", i); }
- ImGui::Text("Keys release:"); for (int i = 0; i < IM_ARRAYSIZE(io.KeysDown); i++) if (ImGui::IsKeyReleased(i)) { ImGui::SameLine(); ImGui::Text("%d", i); }
+ ImGui::Text("Keys down:"); for (int i = 0; i < IM_ARRAYSIZE(io.KeysDown); i++) if (io.KeysDownDuration[i] >= 0.0f) { ImGui::SameLine(); ImGui::Text("%d (0x%X) (%.02f secs)", i, i, io.KeysDownDuration[i]); }
+ ImGui::Text("Keys pressed:"); for (int i = 0; i < IM_ARRAYSIZE(io.KeysDown); i++) if (ImGui::IsKeyPressed(i)) { ImGui::SameLine(); ImGui::Text("%d (0x%X)", i, i); }
+ ImGui::Text("Keys release:"); for (int i = 0; i < IM_ARRAYSIZE(io.KeysDown); i++) if (ImGui::IsKeyReleased(i)) { ImGui::SameLine(); ImGui::Text("%d (0x%X)", i, i); }
ImGui::Text("Keys mods: %s%s%s%s", io.KeyCtrl ? "CTRL " : "", io.KeyShift ? "SHIFT " : "", io.KeyAlt ? "ALT " : "", io.KeySuper ? "SUPER " : "");
ImGui::Text("NavInputs down:"); for (int i = 0; i < IM_ARRAYSIZE(io.NavInputs); i++) if (io.NavInputs[i] > 0.0f) { ImGui::SameLine(); ImGui::Text("[%d] %.2f", i, io.NavInputs[i]); }
