Message-ID: <00c601bd8966$56a279c0$3d4e08c3@arthur>
From: "Arthur" <arfa AT clara DOT net>
To: "DJGPP Mailing List" <djgpp AT delorie DOT com>
Subject: Re: MMX
Date: Wed, 27 May 1998 12:32:55 +0100
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>   Don't use MMX for a 3D engine.  I have 3 programs that are designed for
>MMX.  Frogger, The Human Body, and "POD", the last two I got with my
>computer.  Frogger has an option of using MMX, and Non-MMX instructions,
the
>MMX at any resolution (including 320x200) is so slow it's impossible to
>play.. the Non-MMX play is MUCH faster, and gives me a very well frame
rate,
>up to 640x480...  The Ultimate Human Body uses MMX, has no option to not
use
>MMX, and when it does the 3D rendering jobs, it takes about 2 seconds to
>load the next frame.. POD does ok, so their engine is better than the
>others, but it's still rather slow.  I would suggest doing is do the best
>you can with a normal 3D-engine, and design support for 3D accelerated
>cards.
>
>BTW, I'm doing this on a P166MMX, with a non-accelerated graphics card.
POD
>and Human Body were running in 16-bit mode, Frogger was in 8-bit.


They all run at top speed on my P200MMX with 32MB RAM and a D3D graphics
card. Are you using 16MB RAM? That could explain your problem.
I don't have POD, but I have a demo which allows 640x480x16 bit resolutions
with no hardware acceleration, and it runs FAST. Frogger is slow on any
machine :^).  BTW: have you tried MS FSim '98? I don't think it'd be able to
run as fast as it does in a window without MMX, IMHO.

>Another reason to not use MMX is you will have to learn MMX opcodes, and
>program them yourselves either doing Binary Programming (seeing what the
>bytes would be, and putting in a DB statement), or using NASM and
>incorporating those into your program.


Another great reason to use MMX is you will learn MMX opcodes, and
program them yourselves either doing Binary Programming (seeing what the
bytes would be, and putting in a DB statement), or using NASM and
incorporating those into your program. :^)

James Arthur
jaa AT arfa DOT clara DOT net