Path: utzoo!utgpu!water!watmath!clyde!rutgers!im4u!ut-sally!utah-cs!utah-gr!uplherc!sp7040!obie!terminus!val
From: val@terminus.UUCP (Val Kartchner)
Newsgroups: comp.graphics
Subject: Re: silver color
Summary: metallic in RGB
	 RGB to HLS (or HIS or HSI or etc.)
Message-ID: <70@terminus.UUCP>
Date: 4 Feb 88 21:55:57 GMT
References: <2679@bloom-beacon.MIT.EDU>
Lines: 35

In article <2679@bloom-beacon.MIT.EDU>, tada@athena.mit.edu (Ivan Tadayoff)
writes:
> 
> Does anyone know what values of RGB to use to make a nice looking silver?
> (as in a metallic object?)  I've tried a variety of combinations and none 
> of them seem very pleasing.
> 
     There is no one color that makes silver or any other metallic looking
     colors.  The metallic appearance of an object (or picture) is that the
     metal is reflecting the light that is shinning on it.  This produces
     deviations from the most predominant color giving a metallic look.  If
     the metal is smoother, you get a more perfect reflection, with the tint
     of the metal applied to the reflection.  (e.g.: silver reflects white
     or a bright gray, but gold will reflect a yellow (red and green).)

     -------------------------- HLS to RGB conversion ---------------------

     Does anyone know how to convert colors from RGB (Red/Green/Blue)
     specifications to HLS (Hue/Lightness/Saturation) [HIS
     (Hue/Intensity/Saturation) or HSI].  (We would also be interested in
     converting from HSI to RGB.)  We have VT241/VT340's which require
     specifications in HSI, and we want to plot images that are specified in
     RGB values.  Mathematical specifications would be OK, but PLEASE
     include an English translation.  What we would like is to have a
     function, subroutine, or program (written in a common computer
     language) that does either or both tricks.

				Thank you in advance,
					 -=:[ VAL ]:=-

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