Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!seismo!mcnc!ece-csc!ncrcae!ncr-sd!hp-sdd!hplabs!hplabsz!dleigh
From: dleigh@hplabsz.HPL.HP.COM (Darren Leigh)
Newsgroups: comp.graphics
Subject: Intersecting parametric surfaces
Message-ID: <548@hplabsz.HPL.HP.COM>
Date: Mon, 29-Jun-87 17:30:58 EDT
Article-I.D.: hplabsz.548
Posted: Mon Jun 29 17:30:58 1987
Date-Received: Fri, 3-Jul-87 05:35:45 EDT
Organization: Hewlett-Packard Laboratories
Lines: 22
Keywords: spline Kajiya parametric raytrace

Has anyone had any experience with Kajiya's method for intersecting a
parametric surface with a ray.  It was outlined in
_Computer_Graphics_, July 1982 in an article called "Ray Tracing
Parametric Patches".

I got most of the algorithm done and then was trying to work out the
original polynomials for the general case.  They are huge so I used
Macsyma.  Macsyma died on me, claiming that it was out of memory.
Those polynomials are HUGE (yeah, and maybe my Macsyma implementation
was screwed up, but their still big).  Anyway, is there an easier way?
Am I missing anything obvious?

Any help would be vastly appreciated.  Also any Macsyma help on
polynomials would be good.  Are you a Macsyma guru?  Send me your
address!

Thanks in advance.

Darren Leigh
dlleigh@media-lab.mit.edu
or
dleigh@hplabs.hp.com