Path: utzoo!attcan!uunet!lll-winken!ames!ncar!tank!uwvax!dogie!yahnke@vms.macc.wisc.edu
From: yahnke@vms.macc.wisc.edu (Ross Yahnke, MACC)
Newsgroups: comp.sys.mac.programmer
Subject: Re: help! large offscreen map
Message-ID: <1105@dogie.edu>
Date: 17 Jan 89 15:06:03 GMT
Sender: news@dogie.edu
Organization: University of Wisconsin Academic Computing Center
Lines: 23

In article <227700002@uxa.cso.uiuc.edu>, wwl90321@uxa.cso.uiuc.edu writes...

>i'm doing my work offscreen and then copy bits into an onscreen window.
>...from fiddling I think that somehow my offscreen is
>being clipped by the desktop!  
>...Am I missing a mysterious third rect that produces
>the visible region? The book says never touch visrgn so I guess
>I won't. Any other help would be much appreciated! please send
>email. thanks!

The book sez don't touch visrgn but go ahead and do it anyway. When you
do your OpenPort for your offscreen bitmap the visRgn of the port is 
init'ed to be the size of the desktop, (IM-1, p.163). But the visRgn is
only used for onscreen clipping of windows, in fact p. 149 sez, "The
visRgn has no effect on images that aren't displayed on the screen."

So the solution is to go into the grafport and reassign it to an
infinitely large region.

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