Path: chuka.playstation.co.uk!news
From: James Russell <James_Russell@scee.sony.co.uk>
Newsgroups: scee.yaroze.programming.3d_graphics
Subject: Re: Rotating about an arbitrary axis?
Date: Fri, 18 Sep 1998 17:39:18 +0100
Organization: Sony Computer Entertainment Europe
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James Shaughnessy wrote:
> 
> What I need is to know what matrix transformation I need to apply to
> a ball so it will rotate in the direction it is moving:  eg.

Well, firstly, to answer your question, you need to 'roll' about the X axis and then the Y for the
direction of the ball. Use RotMatrixX(RollAmount) followed by RotMatrixY(CompassDirection) to create
such a matrix.

Secondly, just an observation... Why are you using 3D for the balls? Wouldn't sprites be faster? I
guess you must be going for proper lighting or something...

Cheers,

James


-- 
== James_Russell@scee.sony.co.uk                +44 (171) 447-1626
== Developer Support Engineer - Sony Computer Entertainment Europe

Ask not for whom the bell tolls, let the machine get it.