Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!iuvax!uxc.cso.uiuc.edu!tank!eecae!netnews.upenn.edu!grad2.cis.upenn.edu!ranjit From: ranjit@grad2.cis.upenn.edu (Ranjit Bhatnagar) Newsgroups: comp.graphics Subject: Re: Turbulence functions Summary: ...and 3d texture maps Message-ID: <14364@netnews.upenn.edu> Date: 13 Sep 89 19:34:11 GMT References: Reply-To: ranjit@grad2.cis.upenn.edu.UUCP (Ranjit Bhatnagar) Organization: University of Pennsylvania Lines: 30 >> [Ranjit]The combination of 3-d spacial texture mapping with a nice 3-d >> turbulence function can give really neat results for marble, wood, >> and such. >Could someone please post an example of a turbulence function, or >provide pointers to one? I am very interested in using this idea in a >ray tracer that I am working on. Thank you! > Drew Olbrich po0o+@andrew.cmu.edu The ideas of 3-d texture maps (perhaps we should call them texture fields? :-) and the turbulence function appear - along with lots of other neat ideas - in SIGGRAPH 85: Solid Texturing of Complex Surfaces - Darwyn Peachey An Image Synthesizer - Ken Perlin If someone's collecting a Commonly-Asked Questions of comp.graphics file, this should probably go in there to encourage more people to read these papers. In March, Jon Buller (bullerj@handel.colostate.edu) posted a set of turbulence routines in Pascal, and William Dirks (dirks@oak.cis.ohio-state.edu) posted a translation into C in April. I never got around to trying them myself (drat), but I'll send a copy of those postings to interested parties. Perhaps Jon and William would like to repost their code? - ranjit "Trespassers w" ranjit@eniac.seas.upenn.edu mailrus!eecae!netnews!eniac!... "Such a brute that even his shadow breaks things." (Lorca)