From: "DeepBlack \(Murray Evans\)" <deepblack AT dial DOT pipex DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Masking (?)
Date: Fri, 10 Mar 2000 21:44:47 -0000
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

I have a 24-bit bitmap in a datafile, and want to place it onto the screen.
There are parts of the bitmap which I would like to not be seen (i.e, be the
same colour as the background that the bitmap is placed over.) How do I do
this (with allegro preferrably)?
the allegro docs talk about masking, which I think is what I want. can that
be done in software, or soes it have to be a hardware thing?