Path: chuka.playstation.co.uk!news
From: markt@mincom.com
Newsgroups: scee.yaroze.programming.3d_graphics
Subject: Object rotation
Date: 1 Sep 1997 7:39:18 GMT
Organization: PlayStation Net Yaroze (SCEE)
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From: Mark Theyer <markt@mincom.com>
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Hi,

In 'most' matrix based graphics systems is it correct in saying
that transforming and then rotating an object will result in a
position as illustrated... ?

(|| = object,\\ = rotated object)                 

                          \\ 2:rotate(0,0,35)



                  .--------> ||
                0,0,0           1:translate(10,0,0)

Now, is it also true in saying if we swap the method, rotate and
then translate we get this... ?
 
        1:rotate(0,0,35)
                  \\--------> \\
                0,0,0            2:translate(10,0,0)

OK, next question... Is it correct in saying that rotating a 
PSX object will result in a rotation at the transformed position
around the object's origin (0,0,0)? In other words is the transformation
independant of the 3x3 scale, rotation info' and is applied last?

If this is the case may I ask why? 

Does this mean I can only rotate (and scale) an object around the
origin?

Mark Theyer
markt@mincom.com