From:	Shawn Hargreaves <Shawn AT talula DOT demon DOT co DOT uk>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Allegro lines vs. pixels
Date:	Mon, 17 Feb 1997 21:45:21 +0000
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Distribution:	world
Message-ID:	<UDT2X3AxFNCzEwWX@talula.demon.co.uk>
References:	<330792EC DOT 7443 AT byu DOT edu>
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To:	djgpp AT delorie DOT com
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Christian Bird writes:
>I've got a question for some of those allegro guru's out there.  I'm
>writing a program right now that uses lines of length 2 to 4 pixels
>long.  I'm using 640x480x256 grphics mode and I'm wondering if it's
>faster to do a vline or 2 inline _putpixel's.  I would think that doing

Off the top of my head, I'd guess that using _putpixel would be faster
up to lines of at least 8 or 10 pixels, but you'd have to time it to be
sure.

Vertical lines are one of the least optmisable drawing routines in any
case, because they can't be expanded to copy multiple pixels at a time,
and they have a nasty habit of crossing SVGA bank boundaries (thus
requring multiple bank switches per line).

/*
 *  Shawn Hargreaves - shawn AT talula DOT demon DOT co DOT uk - http://www.talula.demon.co.uk/
 *  Ghoti: 'gh' as in 'enough', 'o' as in 'women', and 'ti' as in 'nation'.
 */

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