ifdef freeglut extensions properly

examples/example_freeglut_opengl2/main.cpp

@@ -91,7 +91,7 @@ int main(int argc, char** argv)
 {
     // Create GLUT window
     glutInit(&argc, argv);
-#ifndef __APPLE__
+#ifdef __FREEGLUT_EXT_H__
     glutSetOption(GLUT_ACTION_ON_WINDOW_CLOSE, GLUT_ACTION_GLUTMAINLOOP_RETURNS);
 #endif
     glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE | GLUT_MULTISAMPLE);

examples/imgui_impl_freeglut.cpp

@@ -72,7 +72,7 @@ void ImGui_ImplFreeGLUT_InstallFuncs()
     glutMotionFunc(ImGui_ImplFreeGLUT_MotionFunc);
     glutPassiveMotionFunc(ImGui_ImplFreeGLUT_MotionFunc);
     glutMouseFunc(ImGui_ImplFreeGLUT_MouseFunc);
-#ifndef __APPLE__
+#ifdef __FREEGLUT_EXT_H__
     glutMouseWheelFunc(ImGui_ImplFreeGLUT_MouseWheelFunc);
 #endif
     glutKeyboardFunc(ImGui_ImplFreeGLUT_KeyboardFunc);
@@ -181,6 +181,7 @@ void ImGui_ImplFreeGLUT_MouseFunc(int glut_button, int state, int x, int y)
         io.MouseDown[button] = false;
 }
 
+#ifdef __FREEGLUT_EXT_H__
 void ImGui_ImplFreeGLUT_MouseWheelFunc(int button, int dir, int x, int y)
 {
     ImGuiIO& io = ImGui::GetIO();
@@ -191,6 +192,7 @@ void ImGui_ImplFreeGLUT_MouseWheelFunc(int button, int dir, int x, int y)
         io.MouseWheel -= 1.0;
     (void)button; // Unused
 }
+#endif
 
 void ImGui_ImplFreeGLUT_ReshapeFunc(int w, int h)
 {