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From: dorner@pequod.cso.uiuc.edu (Steve Dorner)
Newsgroups: comp.sys.mac.programmer
Subject: Re: A few Q's from a novice...
Message-ID: <1990Sep5.162541.27771@ux1.cso.uiuc.edu>
Date: 5 Sep 90 16:25:41 GMT
References: <10602.26e3f796@ecs.umass.edu>
Sender: news@ux1.cso.uiuc.edu (News)
Reply-To: dorner@pequod.cso.uiuc.edu (Steve Dorner)
Organization: University of Illinois at Urbana-Champaign
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>1)	How do most people handle updating the contents of a window when 
>something in front of the window disappears (another window, dialog, etc)?  
>Do you use off-screen copies of the contents of your windows?  Some funky 
>data structure?

I use a "funky data structure".  Whatever you use, it's a good idea to do
ALL your drawing in response to update events (unless you're doing animation
of some kind).  Then, when you want to redraw a particular thing (because it
has changed, perhaps), you merely Inval{Rect,Rgn} it, and the system will
eventually send you an update event for it, at which time you can draw
what needs to be drawn.

This approach WILL simplify your life, at least a little.

Steve
--
Steve Dorner, U of Illinois Computing Services Office
Internet: s-dorner@uiuc.edu  UUCP: uunet!uiucuxc!uiuc.edu!s-dorner