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From: ramakris@bloss.cs.vt.edu (S.Ramakrishnan)
Newsgroups: comp.windows.x
Subject: Re:  Color maps....
Message-ID: <1077@creatures.cs.vt.edu>
Date: 2 Apr 91 04:20:50 GMT
References: <9103280703.AA16051@lightning.McRCIM.McGill.EDU>
Sender: usenet@creatures.cs.vt.edu
Reply-To: ramakris@bloss.cs.vt.edu (S.Ramakrishnan)
Organization: Virginia Tech Computer Science, Blacksburg, VA
Lines: 20

In article <9103280703.AA16051@lightning.McRCIM.McGill.EDU> mouse@lightning.mcrcim.mcgill.EDU (der Mouse) writes:

>To do this, you have to allocate read/write cells instead of read-only
>cells (minor wart, but more or less unavoidable).  What you actually
>want is to have a group of color cells that have all but four bits
>equal, then those four bits give you the sixteen combinations you want.
>The routine to allocate colormap cells this way is XAllocColorCells;
>you would want to call it with nplanes=4 and npixels=1.  If it's

  In requesting for read/write cells, should n't one ensure that a
  PseudoColor/DirectColor visual is available at all , before using
  AllocColorCells ? Probably too important to be explicitly mentioned.



--
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 S Ramakrishnan, CS Dept, McBryde Hall, VaTech, Blacksburg, Virg.  24061-0106
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