Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!think.com!spool.mu.edu!uunet!van-bc!ubc-cs!news.UVic.CA!csr!bcorrie From: bcorrie@csr (Brian Corrie) Newsgroups: comp.graphics Subject: Re: Scene Description Standard Message-ID: Date: 30 Apr 91 16:05:17 GMT Article-I.D.: csr.bcorrie.673027517 References: <1991Apr30.003612.16050@mks.com> <30137@rouge.usl.edu> Sender: news@sol.UVic.CA Organization: University of Victoria Lines: 49 Nntp-Posting-Host: csr.uvic.ca msr@gator.cacs.usl.edu (Srinivas R. Manapragada) writes: >In article <1991Apr30.003612.16050@mks.com> david@mks.com (David Rowley) writes: >>One of the harder problems in producing snazzy computer graphics seems >>to be the modelling, rather than the rendering. One reason for this is >>the lack of a standard modelling format. >> >>Would it make sense to define a new, say text-based, format to describe >>a world, such that a renderer could use as much information from it >>as possible, and chuck the rest ? >> ... >>Does it make sense ? Anyone interested ? >Yes it would be nice to have a standard. However it should be more expressive >and powerful than the language of say rayshade, which allows hierarchical >objects to be defined rather easily. However one should also have some kind of >procedural features. For example say while describing a forest I should be able >to define it as > for(x = 0; x < 100; x++) > for(y = 0; y < 100; y++) > FirTree(x + dither(), y + dither()); > > where FirTree is the parameterized object and dither provides a small >amount of +- deviation. Ofcourse the object need not have its position as a >parameter since they may be more naturally handled by modelling transformations >but it may be more important to parameterize by, say, the surface color, texture >etc. >Also very compact descriptions arise through the use of fractals, IFS's etc., I >wonder if they can be pulled into the language. >_Srini_ Makes wonderful sense. In fact, this is what the RenderMan Specification tries to do. Its definition contains a multitude of primitves, CSG, etc. etc. One could write a book on it.... Wait a second, there is a book on it 8-) Check out ``The RenderMan Companion'' by Steve Upstill. Its published by Addison Wesley and the ISBN number is 0-201-50868-0. A more technical document is available from PIXAR as well, giving the gory details of the interface. Note that ``The RenderMan Companion'' is a pretty good graphics text as well. It should be possible to do all of the above with the RenderMan Interface. B -- Brian Corrie (bcorrie@csr.uvic.ca) Under the most rigorously controlled conditions of pressure, temperature, volume, humidity and other variables, the organism will do as it damn well pleases. Sounds like some of the code I have written...... 8-)