Newsgroups: comp.sys.amiga.misc Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!menudo.uh.edu!karazm.math.uh.edu!jet From: jet@karazm.math.uh.edu (J Eric Townsend) Subject: Re: Real Time ray tracing Message-ID: <1991Jun27.064357.29001@menudo.uh.edu> Sender: usenet@menudo.uh.edu (USENET News System) Nntp-Posting-Host: karazm.math.uh.edu Organization: University of Houston -- Department of Mathematics References: <13306@uwm.edu> <15882@exodus.Eng.Sun.COM> Date: Thu, 27 Jun 1991 06:43:57 GMT In article <15882@exodus.Eng.Sun.COM> cmcmanis@stpeter.Eng.Sun.COM (Chuck McManis) writes: >I saw a demonstration of some real time ray tracing on a massively parallel >machine (I believe it was a connection machine with something like 4096 >processors) anyway, ray tracing is well enough known that it is probably >possible to build a dedicated ray tracing vector unit that costs less >than these massively parallel boxes. Vector raytracing is tough. The problem is that there are all these conditionals mixed in your code. I read a how-to paper on vectorizing ray tracing a while back, I think it was (quick grep of ~/bib) oops, I can't find it. Take a look at the Ray Tracing abstracts, there's a copy for ftp from karazm.math.uh.edu. At any rate, an RS/6000 model 320 with 32Mb of ram is slightly slower than a SparcStation-2 w/24 Mb of ram on my ray tracer. Why? Because it never has a chance to cache and use multiple instructions. (If I do exhaustive ray tracing, it's even worse. :-) -- J. Eric Townsend - jet@uh.edu - bitnet: jet@UHOU - vox: (713) 749-2126 Skate UNIX! (curb fault: skater dumped) PowerGlove mailing list: glove-list-request@karazm.math.uh.edu