Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uwm.edu!ux1.cso.uiuc.edu!peltz
From: peltz@cerl.uiuc.edu (Steve Peltz)
Newsgroups: comp.sys.mac.programmer
Subject: Color/Gray lookup
Message-ID: <1990Nov27.150724.24164@ux1.cso.uiuc.edu>
Date: 27 Nov 90 15:07:24 GMT
Sender: news@ux1.cso.uiuc.edu (News)
Organization: UIUC Computer-based Education Research Lab
Lines: 14

I've got an application that does color drawing by simply using the default
color palette and doing RGBForeColor() and RGBBackColor().

I've noticed that if I set the display to plot in grays that the translation
from color to gray is not very useful. For example, setting only one of R, G,
or B will always map to black, even if the remaining one is set to 100%.

I thought it did color matching to gray by simply using the standard luminance
formula. Am I doing something wrong, or is this a known mis-feature, and what
can I do to overcome it short of using my own palettes and reverse color
lookup?
--
Steve Peltz
Internet: peltz@cerl.uiuc.edu	PLATO/NovaNET: peltz/s/cerl