Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!newstop!exodus!appserv!angel.Eng.Sun.COM!henry
From: henry@angel.Eng.Sun.COM (Henry McGilton)
Newsgroups: comp.lang.postscript
Subject: Re: Psroff meets Pageview.
Summary: Latest Update
Message-ID: <427@appserv.Eng.Sun.COM>
Date: 8 Feb 91 21:20:41 GMT
References: <1272@ecicrl.ocunix.on.ca> <1991Feb8.005229.18689@TIRS.oz.au>
Sender: news@appserv.Eng.Sun.COM
Lines: 39

In article <1991Feb8.005229.18689@TIRS.oz.au>, pete@TIRS.oz.au (Peter Bartel) writes:
    *   From article <1272@ecicrl.ocunix.on.ca>, by clewis@ferret.ocunix.on.ca 
    *   (Chris Lewis):
    **  One of the people using psroff is using X11 pageview to
    **  view the Postscript that psroff generates, and is encountering
    **  a problem which someone may be able to solve.  Namely, each
    **  page overlaps rather than replaces the previous page.
    **  (eg: no erase is occuring of the previous page)
    **  Does anybody know why pageview could be doing this?  Any suggestions
    **  that might solve the problem?

    *   An extract from the groff 1.0 Makefile might shed a little light:
Stuff about DBROKEN_SPOOLER deleted.

    *  I played around with the %%EndProlog line withoug success. But
    *  then, I don't know much about postscript.

I looked into the problems and communicated some answers to Chris Lewis.

One problem you may run into is that the font definitions in the
psroff prolog uses the PostScript  reversepath  operator, which NeWS
doesn't implement.   I believe you'll only run into this problem if
your document contains certain kinds of math asking for one of the
special large parentheses building characters.  That is, if you use
eqn to do either of the constructs  left (  or  right ).

The problem of the overlapping pages is caused by an extraneous  %!
sign halfway through the psroff prolog.  PageView doesn't parse this
correctly, making an invalid assumption that the PostScript following
is an included file.  PageView looks for the end of the
included document, doesn't find it, and ends up assuming that the
entire document is one page, hence the overlapping problem.

For those who need instant gratification, look for the line that
reads:
	%       bracket building font
and delete the line that follows it.

	........  Henry