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From: anand@boris.mscs.mu.edu (Anand Prahlad)
Newsgroups: comp.graphics
Subject: Color-map question
Keywords: ray tracing, color-map
Message-ID: <560@spool.mu.edu>
Date: 8 Mar 91 00:30:41 GMT
Sender: news@spool.mu.edu
Distribution: usa
Organization: Marquette University - Department EECE
Lines: 24

I have developed a rudimentary ray tracer on an APOLLO DN3500 (which   
incidentally has only 8 bit color capability).  I have replaced the
default (16 color) color map with a 256 color one.  
The RGB triplet that I get from my ray tracer is mapped into some arbitrary
location in the color table which results in the pixel being illuminated
with that color.  The problem is with reflections and refractions.  
That is, the color of an object in my scene does not necessrily match
the color of its reflection.  This is because the RGB triplet returned
for a pixel in the reflected object is different from the RGB of the 
original object and as such maps into a different location in the
color table which corresponds to a totally different color (and not
just a different shade of the original, as one might expect).  This 
results in unnatural reflections and refractions.  

If anybody out there has ideas about what kind of a color map I should
be using, I'll be glad to hear from you.
 
Please reply by e-mail to :
		anand@boris.mscs.mu.edu
			or
		5038prahlada@mucsd.bitnet 

							Thanks
							Anand.