Tests whether a port does quality drawing.
A graphics port.
The generic function
port-drawing-mode-quality-p returns true if the graphics port
does quality drawing.
A port does quality drawing if both
1. it was not made with
2. the underlying library supports quality drawing.
Microsoft Windows and Cocoa always support quality drawing, GTK+ supports it from version 2.8 and greater, but Motif never supports it.
CAPI User Guide and Reference Manual (Macintosh version) - 3 Aug 2017