Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!sun-barr!decwrl!adobe!jeynes
From: jeynes@adobe.COM (Ross A. Jeynes)
Newsgroups: comp.lang.postscript
Subject: Re: AFM files: of any use?
Message-ID: <1460@adobe.UUCP>
Date: 18 Nov 89 01:50:21 GMT
Reply-To: jeynes@adobe.UUCP (Ross A. Jeynes)
Organization: Adobe Systems Incorporated, Mountain View
Lines: 38

Yes, AFM files are useful entities.

AFM files were originally created to communicate character width information 
to application programs which needed to caclulate linebreaks, etc.  Additional
information is also contained in the AFMs, including kerning data, composite
character data, and general font information, such as the family name, weight,
underline position, version, etc.  The character width information is for the
printer font, not the screen bitmaps, though these widths are usually very
close.

AFM files for a particular font are shipped with the font package.  Because 
printer manufacturers do not ship the AFMs for the ROM-resident fonts with
their printers, these (and in fact all) AFMs are available from Adobe via
the following channels:
   1) Developer Support organization; call (415) 961-4111 for a recording 
      of more information.  There is a small charge for media and handling.
   2) From the Adobe file server.  If you haven't used the Adobe file server
      before, send the message "help" to ps-file-server@adobe.com
   3) From CompuServe.  Enter "Go Adobe" at the CompuServe prompt.

We also have C source code for an AFM parser available from these same sources
if you are interested in supporting AFMs from your application. 

Some developers do ship AFMs with their products so that users can generate
a PostScript language file using the correct character metrics, then take the
file to a service bureau that actually has the font.  While we don't encourage
distributing all of the AFMs with products (because there are a lot of them,
and they are about 10K apiece), we do encourage application support of AFMs
rather than hard-coding widths into the application (hence the availability
of the AFM parser).  This provides a more general font-support solution to
Joe Consumer (who is a personal friend of mine :-).

I hope this clears up some of the confusion.

 
Ross Jeynes              
Developer Support                                   jeynes@adobe.com
Adobe Systems Incorporated                 {sun|decwrl}!adobe!jeynes