macos: explicitly request color and alpha sizes

diff --git a/gdk/macos/gdkmacosglcontext.c b/gdk/macos/gdkmacosglcontext.c
index e3d72e54d94c58c310e51ac6a9839e3c32f41969..df8f66b1369d92ad545e488324ec97876bcbba65 100644 (file)
--- a/gdk/macos/gdkmacosglcontext.c
+++ b/gdk/macos/gdkmacosglcontext.c
@@ -101,6 +101,8 @@ create_pixel_format (int      major,
     NSOpenGLPFAAccelerated,
     NSOpenGLPFADoubleBuffer,
     NSOpenGLPFABackingStore,
+    NSOpenGLPFAColorSize, 32,
+    NSOpenGLPFAAlphaSize, 8,
 
     (NSOpenGLPixelFormatAttribute)nil
   };