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From:	sturmyg AT cs DOT man DOT ac DOT uk (Graham Sturmy)
Newsgroups:	rec.games.programmer,comp.os.msdos.djgpp,comp.os.msdos.programmer,comp.graphics.algorithms
Subject:	Re: Fixed-point Math Library
Date:	4 Oct 1995 10:14:53 GMT
Organization:	Dept of Computer Science, University of Manchester, U.K.
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Just a couple of points about the previous article and the original:
	1) 10240 is NOT a power of 2 (8192 or 16384 are however)
	2) If you are rotating your 3D coordinates each time from the 
	   previously calculated ones then the errors will be compounded.
	   The best thing to do is rotate and translate from a fixed (and
	   error free original) which is never altered so the error you end
	   up with is small and thrown away after it has been calculated.

As for the speed up, as in the previous article it is much quicker to use
powers of two to shift (x<<13) in C will multiply by 8192.

Graham Sturmy - Undergrad, University of Manchester, U.K

PS. I would like to apoligise to the person I accidentally mailed yesterday.

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