- macOS 10.0–10.14Deprecated
Value is a bit mask of supported physical screens. All screens specified in the bit mask are guaranteed to be supported by the pixel format. Screens not specified in the bit mask may still be supported. The bit mask is managed by the CoreGraphics’s DirectDisplay, available in the
CGDirect header of the ApplicationServices umbrella framework. A
CGDirect must be converted to an OpenGL display mask using the function
CGDisplay. This attribute is not generally useful.