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From: arenberg@earthquake.Berkeley.EDU (Jeff Arenberg)
Newsgroups: comp.sys.mac.programmer
Subject: smooth scrolling
Message-ID: <1989Dec6.232002.3759@agate.berkeley.edu>
Date: 6 Dec 89 23:20:02 GMT
Sender: usenet@agate.berkeley.edu (USENET Administrator;;;;ZU44)
Reply-To: arenberg@ocf.Berkeley.EDU (Jeff Arenberg)
Distribution: usa
Organization: ucb
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I am working on some code that updates a window from an offscreen
bitmap with scroll bars.  Currently the code that handles a scroll
looks something like :

	ScrollRect (therect, dh, dv, &rgn);
	InvalRgn (rgn);
	CopyBits (...);

The problem is that the updated edges of the window flash for every
scroll.  I know some programs don't have this effect.  Can someone
please send me the proper code to handle this operation?  As always,
thanks in advance, and please respond directly, I can't read news
often enough to stay current.

Jeff Arenberg
arenberg@ocf.berkeley.edu