As per the subject, if I extract a font's info using ttx and I want to find where each glyph stroke begins and ends? Since I don't know much about the tables in fonts, I am not sure what values represent the lines used to draw a glyph.

Has anyone ever found a way to output items like the GSUB Feature values, back out to say imagemagick? For example, sending unicode values is no problem, but since items like SALTS don't have a unicode value, how can you print those items to image in say imagemagick/php? Any ideas?