Path: utzoo!attcan!uunet!decwrl!bacchus.pa.dec.com!news
From: pjs@basalt.pa.dec.com (Philip Schneider)
Newsgroups: comp.graphics
Subject: Re: Arbitrarily-Shaped Light Sources
Message-ID: <1990Sep17.175237.12066@wrl.dec.com>
Date: 17 Sep 90 17:52:37 GMT
Sender: news@wrl.dec.com (News)
Followup-To: comp.graphics
Organization: DEC Advanced Technology Development, Palo Alto, CA
Lines: 38


Steve Hollasch writes :


>    How do raytracers make light sources out of arbitrary objects?  I
>thought a while back that one approach would be to find the direction to
>the object from the illuminated point, fire a random cone of rays at the
>object, and assign some fraction of the object's light to the point for
>each unobstructed ray .......


    Get in touch with the University of Washington Department of Computer
Science.  Two or three years ago Dan O'Donnell wrote an M.S. thesis
on what he called "solid light sources".  (Sorry, my copy is in a box
right now, so I don't recall the exact title :-(  

    Real nice work, as I recall, and the resulting pictures were pretty 
interesting -- one of them featured a coffee mug, with steam rising from it
that turned into a glowing "neon sign" light formed into the shape of 
the word "Espresso" (of course, I'm biased from having worked alongside him 
at the UW graphics lab :-)












--
Philip J. Schneider			| pjs@decwrl.dec.com
DEC Advanced Technology Development	| decwrl!pjs
100 Hamilton Avenue			| (415)853-6538
Palo Alto, CA  94301			| (415)386-8232