SetDitherMap:
PROC [context: Imager.Context, mapEntries: MapEntries];
Fast if mapEntries have been loaded recently.
Does not change the display's color map; see ImagerColorMap.LoadEntries
NOT subject to DoSave, so should be used with caution when dealing with Viewers.
NOP for non-dithered contexts.
DoWithDitherMap:
PROC [context: Imager.Context, mapEntries: MapEntries, action:
PROC];
Fast if mapEntries have been loaded recently.
Does not change the display's color map; see ImagerColorMap.LoadEntries