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From: markv@gauss.Princeton.EDU (Mark VandeWettering)
Newsgroups: comp.graphics
Subject: Re: Colors of the Rainbow
Message-ID: <12655@phoenix.Princeton.EDU>
Date: 4 Jan 90 15:31:41 GMT
References: <2284@isaak.isa.de>
Sender: news@phoenix.Princeton.EDU
Reply-To: markv@gauss.Princeton.EDU (Mark VandeWettering)
Organization: Princeton University
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In article <2284@isaak.isa.de> schwarze@isaak.uucp (Jochen Schwarze) writes:

>I want to display the color spectrum of a rainbow. The wavelengths
>of visible light approximately run from 400 nm to 800 nm. So I'm
>looking for a function that maps a wavelength to the appropriate RGB
>triple. Has anybody done this? Any pointers appreciated.

	Nope.  Nobody has done this. :-)

Okay, okay.  If I wasn't going to help, I wouldn't post.  Dusting off
some of my books on the shelf, I see the traditional (if a text that
was only published last year can be traditional) solution for me.

Roy Hall, "Illumination and Color in Computer Generated Imagery"
1989 Springer-Verlag, ISBN 0-387-96774-5

Hall presents source code to precisely what you wish.  I believe that
you can even ftp the source from freedom.graphics.cornell.edu. (Yup, 
I just checked, in pub/Hall)

Mark VandeWettering