A Boolean value indicating whether the view wants an OpenGL backing surface with a resolution greater than 1 pixel per point.
- macOS 10.7–10.14Deprecated
true if the view wants a high resolution backing surface or
false if it does not.
This property is relevant only for views to which an
NSOpen object is bound (including, but not limited to,
NSOpen objects). Layer-backed views ignore the value in this property and configure their own backing surface at an appropriate resolution.
For compatibility, the default value of this property is
false, which results in a 1 pixel per point framebuffer regardless of the backing scale factor for the display the view occupies. (When the backing scale factor is greater than 1.0 , the rendered surface contents are magnified to the appropriate user size.) Changing the value to
true tells AppKit that it has permission to allocate a higher resolution frame buffer for the view. AppKit uses the backing scale factor and the targeted display to determine whether a higher resolution buffer is appropriate, and it may change the surface resolution when the display mode changes or the view moves to a different display.
When you set this property to
true, the view must be able to convert between view units and pixel units when needed. For example, passing the view’s bounds unmodified to the
gl function yields incorrect results at backing scale factors other than
1. You can use the
convert methods to convert coordinate values to the resolution of the backing store.
To learn more about using OpenGL in your Mac app, see OpenGL Programming Guide for Mac.