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From: chrisg@cbmvax.commodore.com (Chris Green)
Newsgroups: comp.sys.amiga.programmer
Subject: Re: Fast 3d Graphics
Keywords: fast 3d optimizing assembly cycles
Message-ID: <20338@cbmvax.commodore.com>
Date: 3 Apr 91 21:10:13 GMT
References: <9529@star.cs.vu.nl> <1047@cbmger.UUCP>
Reply-To: chrisg@cbmvax.commodore.com (Chris Green)
Organization: Commodore, West Chester, PA
Lines: 19

In article <1047@cbmger.UUCP> peterk@cbmger.UUCP (Peter Kittel GERMANY) writes:
>In article <9529@star.cs.vu.nl> mmblom@cs.vu.nl (Marc Blom) writes:
>>'m wondering how fast 3D graphics can really go. I've written some rotation
>>and perspective routines (in assembly) and profiling shows that 60 % of the
>>time is spend in my routine RotatePoint. This routine rotates 1 point around
>>all three axes in only about 900 cycles minimum and about 1100 cycles maximum.
>>Is this fast ? Can someone do better ? (If so PLEASE mail me how you did it).

	Doing a quick cycle count on my routine, it looks like 485 worst case.
60% is really high to spend on rotation. 10% is more likely for an amiga.
You ARE using a 3x3 matrix and not 3 separate axis rotations, right?

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|Chris Green - Graphics Software Engineer   - chrisg@commodore.COM      f
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|My opinions are my own, and do not         - killyouridolssonicdeath   o
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