Path: utzoo!yunexus!geac!syntron!jtsv16!uunet!lll-winken!lll-tis!helios.ee.lbl.gov!nosc!ucsd!ucsdhub!hp-sdd!hplabs!hpl-opus!hpccc!hp-sde!hpcea!hpbsla!mfox
From: mfox@hpbsla.HP.COM (Martin_Fox)
Newsgroups: comp.lang.postscript
Subject: Re: HPGL -> PostScript Converter wanted !
Message-ID: <500001@hpbsla.HP.COM>
Date: 26 Oct 88 18:11:32 GMT
Article-I.D.: hpbsla.500001
References: <133@dx7.UUCP>
Organization: Hewlett-Packard Boise R & D Lab
Lines: 24


   I would be interested in seeing this one.  Not because I ever need to do
   such conversions;  I'd just like to see how it was done.

   Postscript to/from HPGL comes up every now and then on the net.  The
   problem is that either language would have to be INTERPRETED to handle
   the conversion.  HPGL is a very mode dependent language; to correctly
   handle a given command you must track information from previous commands.
   As a simple example, PD 1, 1 will produce different results depending on
   1) whether your are in relative/absolute mode, 2) polygon/non-polygon mode,
   3) symbol/non-symbol mode, 4) pen up/pen down, etc. etc.  Then there is
   scaling to handle, not to mention the polygon buffer, which behaves
   differently than a Postscript path for stroking and filling.

   I won't even consider Postscript -> HPGL; Postscript has procedures,
   variables, and all the other goodies that make it a general purpose
   language, which HPGL is definitely not.

   By the way, I am not saying HPGL -> Postscript cannot be done, I am only
   saying it is definitely not a script, not if you want to handle the
   majority of HPGL correctly.

   Martin Fox
   Hewlett-Packard
   Boise Division