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- Path: sparky!uunet!sun-barr!west.West.Sun.COM!sunaus!assip.csasyd!condor!daves
- Date: 7 Sep 92 03:20:40 GMT
- Message-ID: <daves.715836040@condor>
- Newsgroups: comp.sys.sun.apps
- Subject: Re: Pageview overlays pages of some postscript files
- References: <8372@sirius.ucs.adelaide.edu.au>
- Organization: Computer Sciences of Australia
- Reply-To: daves@assip.csasyd.oz.au
- From: daves@assip.csasyd.oz.au (David Smart)
- Lines: 48
-
- In <8372@sirius.ucs.adelaide.edu.au> dclunie@ucs.adelaide.edu.au (David Clunie) writes:
-
- > I use pageview on a sparcstation and have found that many postscript files,
- > particularly those that originate from PC or Mac worlds (esp WordPerfect
- > I think) display without error, but all the pages are piled on top of
- > each other as one signal very black page !
-
- > I had hoped that this behaviour would have disappeared moving from OW2
- > to OW3 but sadly it persists ....
-
- > Now I am sure that Sun will say that the postscript files that are a
- > problem are non-standard or something .... that's all very well but
- > they print out ok on an Apple LaserWriter.
-
- > I am sure others have come up with this problem ... is there a simple
- > filter to get around it ? I perused the code of a "good" and a "bad"
- > example and quickly discovered that everything is buried in a morass
- > of macros that seems impossible for a non-Postscript-speaking person
- > like myself to unravel.
-
- > Does anyone have a simple answer ?
-
- The problem is that PageView uses the %%page command to determine where pages
- end. If there aren't any, it doesn't stop. This is the wrong behaviour, as the
- %%page is specifically a comment (called a "body comment" in the "red book").
-
- The red book indicates that an application that "operates on the structure of a
- PostScript page description (to extract page subsets, reverse the order of
- pages, etc.) must pay attention to these boundaries". IMHO, PageView is
- emulating a printer, not an application that extracts page subsets, etc.
-
- It's easy to see why they did it - it makes provision of next/previous
- facilities very easy - but it makes the program incompatible with very correct
- PostScript.
-
- As for a filter - probably too difficult to create a general filter to do this
- (it would have to execute the PostScipt, looking for the page throws, and try
- to insert %%page commands in the correct places). However, it's much easier to
- create filters for your favourite PostScript producers - simply get them to
- shove %%page commands in after the calls to the appropriate page-throw macros.
-
- Dave
-
- > --
- > David Clunie (dclunie@itd.adelaide.edu.au)
- --
- David Smart, Computer Sciences of Australia.
- Net: daves@assip.csasyd.oz.au
-