Newsgroups: comp.lang.smalltalk
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From: sehyo@netcom.com (Sehyo Chang)
Subject: Re: XOR and ParcPlace VisualWorks 2.0
Message-ID: <sehyoD9x64H.872@netcom.com>
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Date: Fri, 9 Jun 1995 19:00:17 GMT
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Smalltalker (rayhorn@mercury.interpath.net) wrote:
: Does anyone out there know how to use an XOR RasterOp to produce a 
: rubber-banded floating rectangle that can be laid down at any position 
: desired on top of a bitmap image (pixmap) that remains static?

: I'd love to hear all about any suggestions anyone could make...

: Thank all.

Used to be easy on 'classical smalltalk (circa V2.3-V2.5)'.
On Visualwork, recommended method is to use double buffering.
Get a pixmap, blast image and draw rectangle. Speed is pretty
reasonable even on 486-25.

-- sehyo chang
