Path: utzoo!mnetor!tmsoft!torsqnt!news-server.csri.toronto.edu!cs.utexas.edu!yale!think.com!snorkelwacker!bloom-beacon!MAYO.EDU!kall
From: kall@MAYO.EDU (Bruce Kall)
Newsgroups: comp.windows.x
Subject: SUMMARY: Transparent Windows
Message-ID: <9011122017.AA25304@neuro_dev.mayo.EDU>
Date: 12 Nov 90 20:17:44 GMT
Sender: daemon@athena.mit.edu (Mr Background)
Organization: The Internet
Lines: 40

My original query was:


> Does anybody have a suggestion about how to make a Xlib window
> transparent except for items drawn in it with GCs in an opaque color?

I received two responses:

From: mouse@Larry.McRCIM.McGill.EDU and barry@visix.com

Both said I could use the SHAPE extensions.  Extenstions are extensions so I
didn't
want to use them since we want a pure Xlib environment.

barry@visix.com also said:

> Just set the background pixmap to `None' and don't set a background
> color.  Also set the border width to zero.  Naturally don't clear the
> window or it will erase what it is covering.
> The problem with this is if the window underneat your button is being
> updated it will screw things up (the information under the transparent window
> will not be updated, so the `see through' portion will retain the
> old information).


This suggestion works well for what I wanted to do which is to put
up a pop-up menu that may be on top of another (or more than one other) window
or on top of an gray scale image.

Thanks to mouse@Larry.McRCIM.McGill.EDU and barry@visix.com.





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