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From: jef@ace.ee.lbl.gov (Jef Poskanzer)
Newsgroups: comp.lang.postscript
Subject: How to paint a non-rectangular image?
Message-ID: <4829@helios.ee.lbl.gov>
Date: 9 Feb 90 21:43:24 GMT
Sender: usenet@helios.ee.lbl.gov
Reply-To: Jef Poskanzer <jef@well.sf.ca.us>
Organization: Paratheo-Anametamystikhood Of Eris Esoteric, Ada Lovelace Cabal
Lines: 15
X-Local-Date: 9 Feb 90 13:43:24 PST

I want to do a PostScript image operation with a mask.  I do not mean
imagemask -- that paints a 1-bit deep image with 1's getting the
current color and 0's getting left alone.  What I want to do is paint
an N-bit image, and have a separate 1-bit mask controlling which parts
of the N-bit image get transferred and which parts get ignored.

I could do it by lasooing the border of the 1-bit mask and converting
it into a clipping list, but that seems extremely grody.  Does anyone
see a better way?
---
Jef

  Jef Poskanzer  jef@well.sf.ca.us  {ucbvax, apple, hplabs}!well!jef
    "When more and more people are thrown out of work, unemployment
                     results." -- Calvin Coolidge