rdd@walt.cc.utexas.edu (Robert Dorsett) (03/16/90)
In article <52297@lll-winken.LLNL.GOV> sierra@das.UUCP (Frankie Sierra) writes: >Wayne, if you are dealing directly with the color manager without using >the palette manager, then you should be able to XOR by yourself. Would you mind providing an example? I've spent about three hours trying to do this, with utterly no success (which means it's a conceptual fault on my part). In effect, I'd like to use an arbitrary background color, and draw lines in an arbitrary foreground RGB color. I would like the foreground lines to behave, in essence, like they were drawn xor'd (as black lines would on a monochrome system). I don't care what color any overlap is, provided that overlap disappears when all lines are erased again. Please keep the discussion high-level--I'd preferably like to do this with as few adjustments to my forecolor()/penmode()-based routines as possible... :-) Perhaps needless to say, my experiments with patxor or srcxor have been, uh, unsatisfactory...:-)