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From: peterk@cbmger.UUCP (Peter Kittel GERMANY)
Newsgroups: comp.sys.amiga.programmer
Subject: Re: Fast 3d Graphics
Keywords: fast 3d optimizing assembly cycles
Message-ID: <1047@cbmger.UUCP>
Date: 3 Apr 91 11:47:14 GMT
References: <9529@star.cs.vu.nl>
Reply-To: peterk@cbmger.UUCP (Peter Kittel GERMANY)
Organization: Commodore Bueromaschinen GmbH, West Germany
Lines: 17

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).

All I hear permanently is, use tables, tables, tables instead of real
(or integer) calculations. At least for the sin and cos calculations.
Estimations about real-life situations show that you don't need tremendous
precision normally (but that depends on your real project). Perhaps even
2D or 3D rotations could be simplified into one (more or less) big table.
It's worth considering in any case.

-- 
Best regards, Dr. Peter Kittel  // E-Mail to  \\  Only my personal opinions... 
Commodore Frankfurt, Germany  \X/ {uunet|pyramid|rutgers}!cbmvax!cbmger!peterk