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From: janssen@holmes (Bill Janssen)
Newsgroups: comp.windows.x
Subject: Re: Handling expose events.
Message-ID: <2623@arisia.Xerox.COM>
Date: 23 Aug 89 20:49:21 GMT
References: <8908220058.AA08564@mote.umb.edu>
Sender: news@arisia.Xerox.COM
Reply-To: janssen@holmes (Bill Janssen)
Organization: PARC.Xerox.COM
Lines: 19
In-reply-to: karl@mote.umb.EDU ("Karl Berry.")

In article <8908220058.AA08564@mote.umb.edu>, karl@mote ("Karl Berry.") writes:
>The specific question is: is it possible to handle expose events using
>Xlib if a bitmap of the window's contents is not kept by the program?

My impression is that the only canonical solution to this problem is to
have the client draw on a Pixmap, not a Window, and to copy appropriately
from the Pixmap to the Window in response to expose events on the Window.
This has some advantages (such as separating the canvas from the viewer)
that might be exploited, but it does require twice (?) as much memory in
the server.

Anyone have a better solution?

Bill

--
 Bill Janssen        janssen.pa@xerox.com      (415) 494-4763
 Xerox Palo Alto Research Center
 3333 Coyote Hill Road, Palo Alto, California   94304