From: Shawn Hargreaves <Shawn AT talula DOT demon DOT co DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Allegro and EGA
Date: Thu, 27 Mar 1997 19:13:39 +0000
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Chris Croughton writes:
>Is it at all possible to use Allegro with only an
>EGA monitor?  Like, only use the sound and timer
>features?  Or has anyone written a driver for the EGA?
>If not, is there some basic incompatibility or could
>I write one?

You should be able to use everything but the graphics routines without
any trouble. Just don't call set_gfx_mode(), because it won't work :-)

Implementing EGA support would be very tricky. The current code assumes
8 bit, 256 color pixels. I'm currently in the middle of extending it to
allow 16 and 32 bit truecolor pixels as well, but the EGA image format
is totally different from both of these (16 colors, with interleaved
bitplanes). It would require a complete rewrite of all the drawing
routines, which would not be a trivial undertaking...


--
Shawn Hargreaves - shawn AT talula DOT demon DOT co DOT uk - http://www.talula.demon.co.uk/
Beauty is a French phonetic corruption of a short cloth neck ornament.