CDColorsExtras.mesa (Viewer definitions for ChipNDale)
Copyright © 1987 by Xerox Corporation. All rights reserved.
Created by Christian Jacobi, June 16, 1987 6:18:43 pm PDT
Created by Christian Jacobi, June 17, 1987 1:10:14 pm PDT
DIRECTORY
CD USING [Layer],
Imager USING [Color];
CDColorsExtras: CEDAR DEFINITIONS =
BEGIN
ColorNotRegistered:
SIGNAL;
--Resumable; On resume, returned color formally works but might look wrong.
InitialColor:
PROC []
RETURNS [Imager.Color];
--This color erases the page; it is necessary on screens because the viewer package
--and tioga use "white" [instead of "all bit cleared"]
--May raise SIGNAL ColorNotRegistered if ColorRegistry was not run
RegisteredColor:
PROC [layer:
CD.Layer]
RETURNS [Imager.Color];
--Returns a registered color representing this layer
--May raise SIGNAL ColorNotRegistered if ColorRegistry was not run, or,
--if ColorRegistry didn't define layer
END.