Path: chuka.playstation.co.uk!news
From: "Michael Enoch" <100413.2514@compuserve.com>
Newsgroups: scee.yaroze.programming.libraries
Subject: Re: Rotation Matrix Functions : Still
Date: 16 Apr 1997 18:10:59 GMT
Organization: PlayStation Net Yaroze (SCEE)
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I started off with the code from the solar2 demo which also does proper
object-relative rotations and doesn't need normalisation for a long time (I
suspect it will be the same code in the demos you mentioned) but it still
needs to be corrected or it does go wobbly after a while.  After all the
vectors and the global matrix is initialised to either 0 for the vectors or
GsIDMATRIX for the matrix, the only code which modifies the matrix is the
code I posted earlier.  The code I posted earlier didn't mess up for a long
time either until I added the normalisation code which made it go freaky. 
Whether I use rsin or the RotMatrix function doesn't make any discernible
difference.  I'm sorry to drag this on for so long but no-one seems to have
code that actually works with normalisation available and I think my
normalisation code is wrong in some way.  I'll try and do as Jim suggests
and put a zip on my web page but it may take a while for me to figure out
how to do that because I've never really tried to set up a web page before.
 I'll post a note when I'm done.

Mike.