From: Shawn Hargreaves <Shawn AT talula DOT demon DOT co DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Allegro (bitmap)
Date: Fri, 27 Jun 1997 19:50:03 +0100
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Adam W Lee writes:
>So I'd just say something like 
>
>char *dat;
>dat = (char *) screen->line[0]; 
>
>or something?

That's correct for memory bitmaps, but the physical screen (including
any sub-bitmaps derived from it) is a special case. It doesn't usually
live in your data segment, and it may require hardware bank switching,
so you need to call bmp_write_line() to get an address and use the
farptr functions to access it. This is described in the "Video memory
access" section of allegro.txt...


--
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.