I was wondering if any of the Postscript mavens in the forum could explain
something to me. A typical Adobe font package comes with three files,
extensions .fon, .pfm, .pfb. I gather from the size of the files, .fon's
are the screen fonts, .pfb are the printer fonts and .pfm's are the width
metric information. I recently downloaded a document from one of the Adobe
libraries which described AFM files entitled "AFM Files: An Interchange
Format for Postscript Font Metrics." In it, it refers to ASCII encoded and
human readable files for metrics information.
I've looked at the .pfm files and they ain't "human readable". I did a hex
dump and while that helped a little, I still didn't see anything that would
compose a "width table" in the traditional typesetting sense. My questions
are (1) am I looking at the right place (2) if so, how are the .pfm files
encoded and how can they decoded (3) if you change a kerning pair value in
such a file, can you send the new metrics along with a job to a service
bureau and get the revised kerns.