This is really bothering me. I have an OpenGL window subclassed from NSOpenGLView and rendering via the display link. If I resize the window via the zoom button, the view flickers like crazy until the resize is complete (typically a white window when I'm filling the screen with black). All other reshapes seem to work as expected except for the zoom button. (FYI, It is double buffered). If I force a redraw of the frame in the reshape, everything appears smooth, but that kills the performance of trying to resize the window. I also tried Apple's GLEssentials from the help docs, and saw this problem in there too. *EDIT* OK, resizing the window normally also has flickers too.