Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!newstop!exodus!birdland!rberlin
From: rberlin@birdland.eng.sun.com (Rich Berlin)
Newsgroups: comp.lang.postscript
Subject: Re: postscript back-slash escapes
Message-ID: <6173@exodus.Eng.Sun.COM>
Date: 17 Jan 91 18:50:25 GMT
References: <663@ast.dsd.northrop.com>
Sender: news@exodus.Eng.Sun.COM
Reply-To: rberlin@eng.sun.com
Organization: Sun Microsystems
Lines: 51
cc: paynter@ast.dsd.northrop.com (paynter ann m.)


Ann:

The short answer to your question is that \n, \r etc. are not the
way to render multiple lines in PostScript.  If you need output that

   looks
   like
   this

you need to position each line with its own moveto, e.g.

200 200 moveto (looks) show
200 180 moveto (like) show
200 160 moveto (this) show


The escapes actually *do* work in the sense that the characters they
describe end up in the string.  If your printer and your computer have
a bi-directional link, you can see what I mean: rather than rendering
a string onto the page, you send them back from the printer to the
computer along the i/o channel.  If you do

    (one line) print
    (another line) print

what will come back is

    one lineanother line

while if you do 

    (one line\nanother line) print

what will come back is

    one line
    another line.

------

If you read up on how "show" works, you'll see that when it encounters
the \n in the string, it looks up the character encoded by \n and
comes up empty-handed; what I think is likely is that in the encoding
vector for most fonts, slot #10 (integer value of ascii newline)
contains ".notdef".  I don't really have time to explain this in
detail, so pardon me for referring you to the manual for a more
complete explanation.  In the 1st ed. redbook, Read section 5.4,
beginning on page 93.

-- Rich