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From: klee@wsl.dec.com (Ken Lee)
Newsgroups: comp.windows.x
Subject: Re: Fast Updates
Message-ID: <1991May17.164607@wsl.dec.com>
Date: 17 May 91 23:46:07 GMT
References: <1991May17.220145.22765@atc.SP.Unisys.COM>
Sender: news@pa.dec.com (News)
Reply-To: klee@wsl.dec.com
Organization: DEC Western Software Laboratory
Lines: 14

In article <1991May17.220145.22765@atc.SP.Unisys.COM>, mike@atc.SP.Unisys.COM (Mike Grenier) writes:
|> An individual track (entity) on the screen may move at any time and
|> they more overlap other tracks.

If you have a free color plane or 2, you can do your overlays there.
This is pretty fast and is generally more robust than XOR-based
algorithms.  If you have more than one track to overlay, you can
put them each in a different plane or your can XOR them.

-- 
Ken Lee
DEC Western Software Laboratory, Palo Alto, Calif.
Internet: klee@wsl.dec.com
uucp: uunet!decwrl!klee