From:	Shawn Hargreaves <Shawn AT talula DOT demon DOT co DOT uk>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: [Allegro]Translucent blits
Date:	Fri, 10 Apr 1998 10:48:10 +0100
Organization:	None
Message-ID:	<uTP8uXAareL1EwwG@talula.demon.co.uk>
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To:	djgpp AT delorie DOT com
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Demandred writes:
>Is it worthwhile to create various color tables for various alpha values in
>Allegro, or is there an easier way?

In a truecolor mode you can vary the alpha on the fly, but in 256 color
resolutions you need a table for each blending mode. It is possible to
get several different alpha levels by combining only two tables and
drawing the image multiple times (see the AATEXT addon for an example),
but this still only gives a limited number of levels and it is slower
than using a dedicated table for every alpha value.


--
Shawn Hargreaves - shawn AT talula DOT demon DOT co DOT uk - http://www.talula.demon.co.uk/
"Pigs use it for a tambourine" - Frank Zappa

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