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From: sg1q+@andrew.cmu.edu (Simon Peter Gatrall)
Newsgroups: comp.lang.postscript
Subject: Screening Procedures
Message-ID: 
Date: 29 Jun 88 06:26:32 GMT
Organization: Carnegie Mellon
Lines: 12
In-Reply-To: <174@chip.UUCP>

I've been interested in playing with the procedures PostScript uses to do
halftoning, and I was wondering if anyone else is familiar with this stuff.
One thing that bothers me is that once a pattern is made to represent a
specific gray value, it isn't recomputed.  This makes all the sense in the
world for line and dot screens, but what if you want something that looks like
a texture?  How do you make a circular line screen?

Personally it seems to me that Adobe has made it so that you can redefine the
screen operator, but not in a useful way.  Has anybody out there come up with
neat effects using screen redefintion?

-Simon Gatrall                  sg1q+@andrew.cmu.edu