Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!ames!vsi1!versatc!ritter
From: ritter@versatc.UUCP (Jack Ritter)
Newsgroups: comp.graphics
Subject: Re: Texture mapping by spatial position
Summary: Keep the texture spacebolted to the object
Message-ID: <19393@versatc.UUCP>
Date: 15 Sep 89 19:01:52 GMT
References: <9119@pyr.gatech.EDU> <170@vsserv.scri.fsu.edu> <457@alias.UUCP>
Organization: Versatec, Santa Clara, Ca. 95051
Lines: 28

In article <457@alias.UUCP>, pearce%alias@csri.utoronto.ca (Andrew Pearce) writes:
> In article <14266@netnews.upenn.edu> ranjit@grad1.cis.upenn.edu.UUCP (Ranjit Bhatnagar) writes:
> 
>    <stuff about solid texturing problems with animation and having to
>     store a coordinate frame with each object/texture pair deleted>
> 
It seems to me that you could solve this problem
by transforming the center/orientation of the texture function along
with the object that is being instantiated. No need to
store values, no tables, etc. The texture function must of course
be simple enough to be so transformable. 

Example, wood grain simulated by concentric cylindrical
shells around an axis (the core of the log):
  Imagine the log's center line as a half-line vector, 
(plus a position, if necessary), making it transformable.
Imagine each object type in its object space, BOLTED to
the log by an invisible bracket. As you translate
and rotate the object, you also sling the log around.
But be careful, some of these logs are heavy, and might
break your teapots. I use only natural logs myself.


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