Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!dewey.soe.berkeley.edu!oster
From: oster@dewey.soe.berkeley.edu (David Phillip Oster)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Have you used NewGDevice?
Keywords: newGDevice, refNum, devices
Message-ID: <28415@ucbvax.BERKELEY.EDU>
Date: 16 Mar 89 06:59:09 GMT
References: <1240@mmm.UUCP> <27131@cci632.UUCP>
Sender: usenet@ucbvax.BERKELEY.EDU
Reply-To: oster@dewey.soe.berkeley.edu.UUCP (David Phillip Oster)
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Organization: School of Education, UC-Berkeley
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Here is one case where I needed a GDevice: I had an arbitrary PICT that
used only two colors, neither of them black or white, and I wanted to draw
it with the colors reversed.  Simple, I thought, I'd just render it to an
offscreen pixmap, with a color table of only two entries, swap the
entries, and CopyBits the offscreen pixmap to the screen.  But noooo,
CopyBits uses the inverse table of the current GDevice as an implicit
parameter to figure out how to map the colors of the pixmap source to the
pixmap destination.  I needed to build a gdevice to get the rather
peculiar color map I wanted.  So, I did it. It works.