Xref:	news2.mv.net comp.os.msdos.djgpp:5938
From:	brucef AT central DOT co DOT nz (Bruce Foley)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Setpixel in AT&T inline asm....
Date:	Fri, 12 Jul 1996 06:00:36 GMT
Organization:	Internet Company of New Zealand
Lines:	20
Message-ID:	<4s4sue$qbc@status.gen.nz>
References:	<4rh0g5$m9r AT twain DOT mo DOT net> <4rj0kb$sf3 AT nef DOT ens DOT fr> <836948271snz AT tsys DOT demon DOT co DOT uk>
NNTP-Posting-Host:	brucef.central.co.nz
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Tom Wheeley <tomw AT tsys DOT demon DOT co DOT uk> wrote:


>Although I've never used setpixel routines, I was always under the impression
>that (x + y << 8 + y << 6) is faster than (x + 320 * y).

>.splitbung
>-- 
>* TQ 1.0 * The 'Just So Quotes'.
>OJ's WWW address is http://////////

I think this is true of older processors, but on a 486, a
well designed mul instruction is just as fast (or faster?),
depending on the value of the operands.
Don't know about the Pentium though, since simple
instructions can be useful for keeping both Pipes going.
-Optimising is a hell of a thing...

- Raw text -