Newsgroups: sci.virtual-worlds
Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!batcomputer!cornell!uw-beaver!milton!hlab
From: cdshaw@scapa.cs.ualberta.ca (Chris Shaw)
Subject: Re: Real-time raytrace -- get serious!
Message-ID: <1991May15.050715.28438@milton.u.washington.edu>
Sender: hlab@milton.u.washington.edu (Human Int. Technology Lab)
Organization: University of Alberta, Edmonton, Canada
Date:   Mon, 13 May 1991 22:19:00 -0600
Approved: cyberoid@milton.u.washington.edu




In article <IsntCut&PasteWonderful?> Filip Gieszczykiewicz writes:

> Greetings. Well, I finally got my 486/25 (25MHz)
> Real-time raytracing is not as far away as most of you led me
> to believe.... Why? Well, I did a 320x200x~256 image of a
> sphere, 1/2 cylinder "pillar", and a room with brick walls (one of the
> files included in the .ZIP file). It took less than 2 minutes.
>Filip Gieszczykiewicz  

Whoa, there. That's quite a simple model you traced! Plus you don't say
how deep the reflection tree goes, what the stuff is "made" of....
Also, the 486/25 is a pretty decent CPU. Not the hottest on the planet, but
not shabby either.

So fine, you got a simple model, a fast-ish CPU, a small screen, and 
it takes 2 minutes. To get 0.5 seconds (the absolute minimum)
you need a speedup of 2*60*2 = 240. Just buying 240 486/25's is 
going to cost you $500,000 !!
 
With that kind of money you can buy 1,000,000 gouraud shaded polygons 
per second, without sweating the frame buffer sharing required by a parallel,
real-time ray tracer. After all, the ideal machine for tracing rays is the AT&T
Pixel Machine, and that doesn't deliver real time ray tracing, either!

-- 
Chris Shaw     University of Alberta
cdshaw@cs.UAlberta.ca           Now with new, minty Internet flavour!
CatchPhrase: Bogus as HELL !

