[metapost] Filling complex paths

[Tobias Columbus]

Hi all,

I am currently writing a piece of software that should spit out some MetaPost
code. My input are the closed curves of a glyph and I want to produce MetaPost
code that fills them according to Postscript rules. However, as MetaPost cannot
handle non-contiguous closed paths, this task seems difficult at least. 

Note that the glyphs come from non-Postscript fonts, so that the MetaPost
"glyph" primitive does not work for me. I also tried "graphictext" as described
in the Metafun manual but that turned out to be too inaccurate. I traced the
inaccuracy back to "pstoedit", which is called for "graphictext".

My attempt was to fiddle around with specials and
withprescript/withpostscript.  This attempt turned out to be nonsense as
addto always writes "stroke" or "fill" and my specials were ignored. I
could, of course, write the whole glyph with specials, but I would
prefer a cleaner solution.

Has anybody some experience with this kind of problem? How difficult
would it be to add filling of non-contiguous paths to MetaPost?

Thank you in advance,
Tobias