Path: chuka.playstation.co.uk!scea!peter_alau@playstation.sony.com
From: jamin1@psu.edu (Jamin Frederick)
Newsgroups: scee.yaroze.programming.3d_graphics
Subject: Re: "center"
Date: Tue, 30 Jun 1998 22:23:10 GMT
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That's ok, I appreciate the descriptive reply, thanks.

I thought of another way to do it as well, although it's probably not 
as straightforward.

You could parent your object to a null object (no polygons, or at
least very small ones), with the object offset from the origin of the
null object.  Then if you rotate the null object, you will get the
result with the null obect origin being the pivot point.

The tricky part is having to manage two coordinate systems, especially
when you want to rotate your object around its own center again, and
the translation that has to be done to get this scheme to work.


Jamin

On Tue, 30 Jun 1998 16:51:18 GMT, rs108@mdx.ac.uk (Robert Swan) wrote:

>On Tue, 30 Jun 1998 16:11:17 GMT, jamin1@psu.edu (Jamin Frederick)
>wrote:
>
>>
>>So what you're basically doing is rotating the object as usual (the same 
>>amount you would want to go around the new pivot point) about the origin, 
>>rotating the distance vector of the origin and new pivot point, by the same 
>>amount, and applying that translation to the object?
>>
>>
>>Jamin
>
>basically, yes. but im not known for short concise answers :) (or
>correct ones usually)
>
>Robert