From: pablo@jhunix.hcf.jhu.edu (Pablo A Iglesias)
   Newsgroups: comp.text.tex
   Date: 22 Sep 92 23:49:28 GMT
   Organization: HAC - Johns Hopkins University, Baltimore
   Lines: 52

   I know that there has been a lot of discussion lately on using
   PostScript fonts in TeX documents lately.  I hope that some of you
   might solve a problem that I am having.

   I am using PostScript fonts inside my LaTeX documents.  I do this
   using the Tom Rockiki's "dvips" program. While everything works
   "almost" right, I am having problem with my ligatures and accents.

   I am doing the following:

   in my

   psfonts.map file I have the following

     ptmr       Times-Roman

   and the font files

   -rw-r--r--  1 pi           2192 Sep 22 19:07 ptmr.tfm
   -rw-r--r--  1 pi           1948 Sep 22 19:06 ptmr.vf

   in my tfm and vf directories respectively.

   and as far as I can tell, dvips finds the right files.  What am I doing
   wrong and more importantly, how do I fix it?

   Thanks in advance

   Pablo Iglesias


   PS.  I will tell you what I think is going on.  I didn't create either
   of these font files as I do not have the *.afm files, instead I pulled
   them off the net (I don't remeber where).  My understanding is that
   when afm2tfm creates *.tfm files, they are raw using postscript
   encoding for ligatures.  These have to be "fixed" to match TeX's
   encoding. Is this right? Now, I also have the following times roman
   *tfm file:

   -rw-r--r--  1 pi           1280 Sep 22 19:08 rptmr.tfm

   Which is obviously different.  Is there a good reason why I have two
   tfm files?  I am lost at this point. :-(


Sounds like a mismatch in encoding between the font as actually put out by
your DVI driver and the encoding used in the TFM file.

(1) There ain't no such thing as a `generic' TFM file.  

A TFM file must be set up using a particular font encoding.  The CM fonts
have fixed encoding prescribed by DEK, so there is no issue there.  But,
other fonts may be encoding in different ways to suite different purposes.
For example, the `native' encoding of most Type 1 font is `Adobe
StandardEncoding'.  You may want to use that.  But then again you may not,
because it does not provide acces to the 58 accented characters.

What encoding you use depends on what DVI processor you use. Some can only use
the `native' encoding of the font.  Some allow a two-way choice between
`native' encoding a driver specific encoding.  Others allow choice
of arbitrary encoding vectors.  Some require use of virtual font mechanism
to use non-CM fonts, others don't.

DVI processors come with utilities for making up appropriate TFM files
for whatever encoding that they enforce/allow.

What you have in your case appear to be two TFM files, one apparently set up
for the fonts `native' encoding, the other for a driver-specific encoding.

(2) Plain TeX and LaTeX have hard-wired assumptions about encoding.

Plain Tex and LaTeX assume that accents are were they are in CM text fonts.
If you use another encoding you have to change some of the relevant
macros.  For example, if you use the `native' encoding for some Type 1 text
font, you will find that the accents are not down in the 0 - 31 character
code range, but somewhere high up. 

In your case, the driver specific version has the accented characters where
they are in CM and there should be no need to overried the accent macros.

Finally, if in doubt, RTFM.

Berthold K.P. Horn
Cambridge, Massachusetts, USA
Newsgroups: comp.text.tex