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From: greid@adobe.com (Glenn Reid)
Newsgroups: comp.lang.postscript
Subject: Re: Postscript Bug
Message-ID: <617@adobe.UUCP>
Date: 8 Mar 89 20:33:40 GMT
References: <4571@umd5.umd.edu> <577@adobe.UUCP> <4583@umd5.umd.edu>
Sender: news@adobe.COM
Reply-To: greid@adobe.COM (Glenn Reid)
Organization: Adobe Systems Incorporated, Mountain View
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In article <4583@umd5.umd.edu> butt@umd5.umd.edu (Edgar Butt) writes:

>The program I posted illustrated that on a particular implementation
>of Postscript, namely, version 47.0 on a Laserwriter II NT, varying
>the height (y-dimension) of a rectangle caused its horizontal position
>(x-position) to change.  Whatever numerical method is used to map the
>"ideal" coordinate system onto an actual device, it should be consistent
>and rounding off a y-dimension should not affect x-positioning.
>The other two incarnations of Postscript on which I ran the program
>gave what I consider to be correct results.
>
>I believe the program I posted demonstrated a bug, not a lack of
>understanding.
>
>Edgar Butt (301) 454-2946 butt@umd2.umd.edu


Well, maybe the lack of understanding was on my part, in which case I
apologize.  I have forwarded your original message to our QA
department.  I still believe that it is related to numeric round-off,
but perhaps the roundoff is happening in the interpreter rather than
being inherent in the source program.

Thanks for clarifying.

Glenn Reid
Adobe Systems