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
Organization:	None
Distribution:	world
Message-ID:	<8lWcNGAbtAtzEw57@talula.demon.co.uk>
References:	<199706261804 DOT NAA03968 AT sendit DOT sendit DOT NoDak DOT edu>
NNTP-Posting-Host:	talula.demon.co.uk
MIME-Version:	1.0
Lines:	19
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

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.

- Raw text -