Path: chuka.playstation.co.uk!scea!greg_labrec@interactive.sony.com
From: Aaron James Saarela <saarela@umich.edu>
Newsgroups: scea.yaroze.programming.3d_graphics
Subject: referenced viewing
Date: Sun, 07 Dec 1997 10:52:38 -0500
Organization: SCEA News Server
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Could someone please explain how to use the referenced viewing system?
How does the system go about determing an "up" vector for viewing?  

	THe problem I'm having is this : I'm attempting to view an object from
a slight angle above and slightly behind. However, when I move the
object, the thing seems to "rock" about, kind of like I'm on a boat. 
However, if I specify only the vpz coordiate, placing the view point
right above the object, then there is no twist. 

   	I'm hoping someone can help me with this, because my isomorphic 3d
action game won't look quite the same from an "above-the-object"
viewpoint.