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From: rws@EXPO.LCS.MIT.EDU (Bob Scheifler)
Newsgroups: comp.windows.x
Subject: Re: Shaping windows in Xlib
Message-ID: <9009112244.AA25702@expire.lcs.mit.edu>
Date: 11 Sep 90 22:44:05 GMT
References: <9009112240.AA27376@Larry.McRCIM.McGill.EDU>
Sender: daemon@athena.mit.edu (Mr Background)
Organization: The Internet
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Take a look at mit/lib/Xmu/ShapeWidg.c, particularly the internal function
ShapeEllipseorRoundedRectangle.  Even if you don't know Xt, you should be
able to figure it out.