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From: jeremy@EIK.II.UIB.NO
Newsgroups: comp.windows.x
Subject: Stupid question about Xor'ing a Pixmap
Message-ID: <9010041544.AA16310@pinje>
Date: 4 Oct 90 15:43:26 GMT
Sender: root@athena.mit.edu (Wizard A. Root)
Organization: The Internet
Lines: 36


I hope somebody can give me a hint about the following (what I thought
was a simple problem):

I have a colour machine and want to plot a small cursor in an
application.  The (bits that are set in the) cursor should be coloured
- not just black.  I want to use a pixmap or bitmap as the cursor. The
cursor has to be able to move around and so I need to be able to remove
it and put it somewhere else. The background is not necessarily blank
so I need to put back what was there before. (The cursor shows a point
in a graph, it's not the mouse cursor).

Sooo.. my question is what combination of Pixmap/Bitmap and GC should I
use. I've tried using XCopyPlane of a bitmap with an Xor GC, removing
the old cursor by plotting it again in the same place, but I seem to
come unstuck if the background colour is not 0. I think I got it to
work with background set to 0, but that's not really what I want. I
also got it to work if I draw the cursor using graphics commands, but
that's not really what I want either - the cursor should be user
specifiable as a bitmap.

I'd be most grateful for any hints/tips . I'm tearing my hair out over
this one - I'm sure the answer must be simple.

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 Jeremy Cook                      .----.
 Parallel Processing Laboratory  /    /                      /  /        /
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 email : jeremy@eik.ii.uib.no    | "My other computer is a MasPar MP1208"
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