[HarfBuzz] Selecting fonts for HarfBuzz

[Martin Hosken]

Dear Eli,

> > HarfBuzz handles everything it understands.  It was designed, in fact, such that when combined with
> > FreeType or other external font funcs implementation, it even "handles" font formats it does not understand. 
> > Eg. HarfBuzz doesn't understand BDF, PCF, etc, but if you use hb-ft, you can use hb-ft for everything, and
> > BDF, PCF etc also magically work because HarfBuzz defers to FreeType for glyph access, and simply
> > "passes through" for the rest.  It was designed such that you can keep one shaping code path.  
> 
> We don't currently use hb-ft on Windows.  But thanks, I think I
> understand.

In case it is unclear, harfbuzz can quite happily handle any TTF or OTF whether or not it is designed to be shaped with OpenType or not. So you only need one code path and can simply pass any font to harfbuzz for shaping and harfbuzz will do the Right Thing (TM). Good news, I would suggest :)

Yours,
Martin