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(dvips.info)Reencoding with Afm2tfm

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Reencoding with Afm2tfm
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  The Afm2tfm program creates the TFM and VF files for the virtual font
corresponding to a PostScript font by "reencoding" the PostScript font.
Afm2tfm generates these files from two encodings: one for TeX and one
for PostScript.  The TeX encoding is used to map character numbers to
character names while the PostScript encoding is used to map each
character name to a possibly different number.  In combination, you can
get access to any character of a PostScript font at any position for
TeX typesetting.

  In the default case, when you specify none of the `-t', `-p', or `-T'
options, Afm2tfm uses a default TeX encoding (which mostly corresponds
to the Computer Modern text fonts) and the PostScript encoding found in
the AFM file being read.  The reencoding is also sometimes called a
"remapping".

  For example, the default encodings reencode the acute accent in two
steps: first the default TeX encoding maps the number 19 to the
character name `acute'; then the default PostScript encoding, as found
in the AFM file for an ordinary PostScript font, maps the character
name `acute' to the number 194.  (The PostScript encoding works in
reverse, by looking in the encoding vector for the name and then
yielding the corresponding number.)  The combined mapping of 19 to 194
shows up explicitly in the VF file and also implicitly in the fact that
the properties of PostScript character 194 appear in position 19 of the
TFM file for the virtual font.

  The default encoding of the distributed fonts (e.g., `ptmr.tfm')
mostly follows plain TeX conventions for accents.  The exceptions: the
Hungarian umlaut (which is at position `0x7D' in `cmr10', but position
`0xCD' in `ptmr'); the dot accent (at positions `0x5F' and `0xC7',
respectively); and the Scandinavian A ring `\AA', whose definition
needs different tweaking.  In order to use these accents with
PostScript fonts or in math mode when `\textfont0' is a PostScript
font, you will need to use the following definitions.  These
definitions will not work with the Computer Modern fonts for the
relevant accents.  They are already part of the distributed
`psfonts.sty' for use with LaTeX.

     \def\H#1{{\accent"CD #1}}
     \def\.#1{{\accent"C7 #1}}
     \def\dot{\mathaccent"70C7 }
     \newdimen\aadimen
     \def\AA{\leavevmode\setbox0\hbox{h}\aadimen\ht0
       \advance\aadimen-1ex\setbox0\hbox{A}\rlap{\raise.67\aadimen
       \hbox to \wd0{\hss\char'27\hss}}A}

  As a kind of summary, here are the `CODINGSCHEME's that result from
the various possible choices for reencoding.

default encoding
          (CODINGSCHEME TeX text + AdobeStandardEncoding)

`-p dc.enc'
          (CODINGSCHEME TeX text + DCEncoding)

`-t dc.enc'
          (CODINGSCHEME DCEncoding + AdobeStandardEncoding)

`-T dc.enc'
          (CODINGSCHEME DCEncoding + DCEncoding)

The `CODINGSCHEME' line appears in the VPL file but is ignored by Dvips.