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From: fry@zariski.harvard.edu (David Fry)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Color offscreen pixmap woes...
Message-ID: <6329@husc6.harvard.edu>
Date: 9 Apr 91 15:24:58 GMT
References: <SMARGARI.91Apr8222848@emmy.nmsu.edu> <10972@ncar.ucar.edu>
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It's pretty simple to parse the PICT opcodes to get the color
table for any PixMaps.  Just as simple and more compatible is
to use QuickDraw bottleneck routines to get the color table
from PixMaps.  Quite a number of programs do this, I think.

PixMap color tables are what people most often want, I think,
but the bottleneck approach also allows you to keep track of
all the colors used for Lines, Polys, etc.  This is much
harder, but there's some sample code from Apple on how to do  
this, although it's still an incomplete attempt.

Starting with System 7.0, though, there are Picture Utility
functions which will return all this information for you with
one toolbox call.  Fun times ahead!

David Fry                               fry@math.harvard.EDU
Department of Mathematics               fry@huma1.bitnet
Harvard University                      ...!harvard!huma1!fry
Cambridge, MA  02138