Path: utzoo!utgpu!watmath!watcgl!jdchrist
From: jdchrist@watcgl.waterloo.edu (Dan Christensen)
Newsgroups: comp.sys.sgi
Subject: Re: # of overlay planes
Message-ID: <11110@watcgl.waterloo.edu>
Date: 17 Aug 89 04:49:41 GMT
References: <8908161833.AA12079@castor.wustl.edu>
Reply-To: jdchrist@watcgl.waterloo.edu (Dan Christensen)
Organization: Computer Graphics Lab, University of Waterloo
Lines: 13

In article <8908161833.AA12079@castor.wustl.edu> weinhous@CASTOR.WUSTL.EDU ("Martin S. Weinhous") writes:
>  Many image processing systems, particularly those intended for the
>processing of gray-scale images provide the capability of using 8 bit
>planes of overlay.  This allows the user to, easily,  non destructively,
>annotate the gray-scale images with up to 256 colors.  I'd like to do
>the same on my 4D120-GTX, but can't.

You should be able to use colour map mode and writemasks to achieve
what you want to do.  How many bits do you need for the gray scale?

----
Dan Christensen, Computer Graphics Lab,	         jdchrist@watcgl.uwaterloo.ca
University of Waterloo, Waterloo, Ont.	         jdchrist@watcgl.waterloo.edu