From: Vic <tudor AT cam DOT org>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Accessing BITMAPs Directly in Allegro
Date: Mon, 09 Mar 1998 16:14:39 +0200
Organization: Communications Accessibles Montreal, Quebec Canada
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Colin Walsh wrote:
> 
> Hi all,
> 
> I'm currently trying to eke out as much speed as possible from my 3D
> engine, and I figure that the _putpixel/_getpixel routines (even
> for asm) should be slower that directly accessing the bytes in the
> BITMAP.
I think _putpixel will do just that. there is no clipping or anything. 
> So I was wondering if there is a method of directly accessing the
> bitmap, and if so, how?
Yes, but in 8 bit modes only. You can say bitmap->line[y][x]=color;
or color=bitmap->line[y][x] where y is the Y and x is the X (yes they
are reversed!). But this is just 8 bit modes. I'm afraid for highcolor
you need the putpixel routine.
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