afm(4)                                                     afm(4)



NAME
     afm - Adobe POSTSCRIPT font metrics file format

DESCRIPTION
     afm  files   are   a   standard   interchange   format   for
     communicating  POSTSCRIPT  font metric information to people
     and programs.  The format is ASCII encoded (for  both  human
     and  machine  readability), machine independent, extensible,
     simple to parse, and simple  to  generate.   afm  files  are
     available for all of Adobe Systems' POSTSCRIPT fonts.

     While somewhat verbose, the format is intended to be  easily
     parsed,  with  the  ability for applications to quickly skip
     over items that are not of interest.  It should be  possible
     to  create  simple  line-oriented  parsing programs or tools
     based on awk(1) or sed(1).

     Each afm file contains the information  for  only  one  font
     face.   The  file  begins  with global information about the
     font, followed by sections with character metrics.  The file
     format is line-oriented, each line beginning with a property
     (key) name, followed by the values for that  property.   The
     general  idea  is  to  give key-value tuples (much like in a
     POSTSCRIPT font dictionary).

     The format is:

          key [value value ...]

     Key names are case-sensitive.  All  keys  beginning  with  a
     capital  letter are reserved by Adobe Systems.  The standard
     keys are detailed below, but other keys  should  be  allowed
     and  safely  ignored  by programs not recognizing them.  All
     standard keys begin with  a  capital  letter.   User-defined
     nonstandard entries should begin with a lowercase letter.

     The file begins with the line:

        StartFontMetrics version

     The version described here is 1.0.  The  last  line  of  the
     file is:

        EndFontMetrics

     The following global font keys are defined.   Many  of  them
     are defined as in the top level or FontInfo subdictionary of
     a POSTSCRIPT font dictionary; their meanings  are  described
     in   Appendix  A  of  the  POSTSCRIPT Language Manual.   All
     numeric values are in  the  (1000  unit  per  em)  character
     coordinate system.




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afm(4)                                                     afm(4)



     FontName string
          The name of the font as  presented  to  the  POSTSCRIPT
          findfont operator.

     FullName string
          The ``print name'' of the font.

     FamilyName string
          The font family name.

     Weight string
          The weight of the font.

     ItalicAngle real
          The  angle  (in  degrees  counterclockwise   from   the
          vertical) of the dominant staffs of the font.

     IsFixedPitch boolean
          Indicates monospaced (typewriter) fonts.

     FontBBox llx lly urx ury
          Four integers giving the  lower  left  corner  and  the
          upper right corner of the font bounding box.

             Note:  The bounding box given here is that of the
             flattened   paths,   not   of  the  Bezier  curve
             descriptions.


     UnderlinePosition number
          The position (from the baseline) to place an underline.

     UnderlineThickness number
          Thickness of an underline stroke.

     Version string
          Font version identifier.

     Notice string
          Font name trademark or copyright notice.

     Comment string
          Comment strings may be ignored.

     EncodingScheme string
          A string indicating the  default  encoding  vector  for
          this     font.      The     most    common    one    is
          AdobeStandardEncoding.  Special fonts may simply  state
          FontSpecific.   In  the  future,  other  schemes may be
          employed.

     CapHeight number



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afm(4)                                                     afm(4)



          Top of capital H.

     XHeight number
          Top of lowercase x.

     Ascender number
          Top of lowercase d.

     Descender number
          Bottom of lowercase p.

     The individual character metrics  are  surrounded  with  the
     lines  StartCharMetrics  and EndCharMetrics and consist of a
     list of  keys  and  values  separated  by  semicolons.   The
     characters are sorted (numeric ascending) by character code.
     Unencoded characters follow all of the encoded ones and  are
     distinguished  by  having character code -1.  Each character
     gets one line of description.  Standard keys are:

     C number
          decimal value of default POSTSCRIPT character code  (-1
          if unencoded).

     WX width-x
          Character width in x (y is 0).

     W width-x width-y
          Character width vector.

     N name
          POSTSCRIPT character name.

     B llx lly urx ury
          The character bounding box.

     L successor ligature
          A ligature sequence.  The current  character  may  join
          with   the   character  named  successor  to  form  the
          character named ligature.   Note  that  characters  may
          have more than one such entry.

     Most western language fonts have WX entries  rather  than  W
     ones.  Note that keys are one letter for brevity.  Here too,
     the set is extensible, with unknown entries ignored.   (This
     leaves  room  for addition of new information, for example.)
     A future revision of this format will have  a  specification
     for kerning information.

FILES
     /usr/lib/ps/*.afm
          AFM files in the TRANSCRIPT distribution.




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afm(4)                                                     afm(4)



SEE ALSO
     awk(1), sed(1) in A/UX Command Reference





















































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