partial font downloading

[tech-help@YandY.com (Y&Y Inc)]

> I have a vague recollection that there was some kind of utility out there
> ... that could strip out those characters from a downloaded font so it just
> included the glyphs actually used.

This `partial font downloading' capability has been in DVIPSONE from the 
very beginning in 1990.  On short jobs it can cut PS file size by a factor of 
4 to 8, greatly speeding PS printing (making it fun instead of painful) and 
greatly reducing change of running out of printer VM.  Which a few years 
ago was a big issue with output from TeX, since TeX loves to use lots of fonts.
Less of an issue today when printers tend to come with lots of memory...

It is a good idea to have a way of selectively suppressing it, since one can
come across nasty fonts that are not ATM compatible, yet are legal PostScript,
and without a full PS interpreter built in you can't be sure of handling them.
And then there are `synthetic', `hybrid', `compound' fonts, fonts with `font 
wrappers', and now also Multiple Masters...

Note that Acrobat Distiller release 2.0 and later now also include this
capability
(check `Make Font Subsets'). But this *only* works prorperly if you do an
 undocumented thing:  Add the line

<< /SubsetFonts true /MaxSubsetPct 99 >> setdistillerparams

to `example.ps' in the `startup' directory/folder.  Without this line, it
will use 
`Font Subsets' only only some rare fonts from which you use less than 
about 10% of the characters!   Help pressure Adobe to make 99% the 
efault, *not* 10%! Without this file size is bloated quite unneccessarily 
and `font leakage' is unabatted.

Regards, Berthold.