Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!apple!versatc!ritter
From: ritter@versatc.UUCP (Jack Ritter)
Newsgroups: comp.graphics
Subject: Ray Tracing CSG objects
Keywords: Ray Tracing, Constructive Solid Geometry
Message-ID: <17842@versatc.UUCP>
Date: 2 Jun 89 23:47:34 GMT
Organization: Versatec, Santa Clara, Ca. 95051
Lines: 28

I have a question about ray tracing CSG objects.
Given an object represented by a CGS binary tree
(union, intersection, & difference as operators),
I would like to ray trace it WITHOUT using
spacial subdivision, voxels, etc.
I would like to do it along these lines:

Find the intersection of the ray with each
instantiated half-space surface for the obj. 
(I'm using quadric surfaces).

Sort the intersections by distance from
start of ray.

Go down list, from near to far, stopping
on the surface that would be seen from
that direction. This would be done by
somehow traversing the tree as you go.

Is this doable?

Thanks. I'll summarize.

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