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From: rberlin@birdlandEng.Sun.COM (Rich Berlin)
Newsgroups: comp.lang.postscript
Subject: Re: mirror image
Message-ID: <11437@exodus.Eng.Sun.COM>
Date: 11 Apr 91 20:49:18 GMT
References: <14828@mcdphx.phx.mcd.mot.com> <b#dg8qa@rpi.edu> <11404@exodus.Eng.Sun.COM>
Sender: news@exodus.Eng.Sun.COM
Reply-To: rberlin@Eng.Sun.COM
Organization: Sun Microsystems
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Errata to my previous message:

1) There's an exch that shouldn't be there.

2) I use this so habitually that I forgot you have to compensate
for the margins: (0,0) is the lower left hand corner of the PAPER,
not the printable area.

Here's the corrected code:

printable-area pop 0 translate pop neg 0 translate
-1 1 scale

The second translate moves the origin to be in the same place
relative to the printable area, so any clipping that would have
occurred will be identical.  However, if the physical page margins
aren't the same on the left and the right, the image won't show up
in quite the same place.   In the printers I've seen, this is more
likely to cause a problem if you're working in the paper-feed
direction (typically Y) than in the transverse direction.

Sorry about any inconvenience my earlier errors may have caused.
Thanks to Sean Malloy for pointing them out.

-- Rich