Postscript definitions for special troff characters. File names are
the two character troff names. Each defines a PostScript procedure
that begins with build_ and ends with the character's name. The
build_?? procedure is called with the character width as it's only
argument. The .map files contain extra character data (e.g. image
data) that dpost downloads immediately after the build_?? call,
if the character's font table code field is 2 (rather than 1).
The following PostScript variables are available:
font current font
ptsize current point size
size actual font size - scaled up from ptsize
Don't overuse this stuff!