Support for CJK (TTC files and CFF fonts)

[hadrianw]

Hello,

I would like to ask you to add CJK support. I would like to be able to use system fonts and on my system CJK fonts are provided by TTC files and fonts inside them are using CFF and BASE tables (and probably some others - not my area of expertise) to do that. The last element that would make it worthwhile would be fontsets, but they are simple enough and may be natural to handle with TTC support introduction. That would pretty much cover most text rendering needs outside of a whole complex shaping area AFAIU.

I don't want to spam you with issues, but there are a few requests listed in order of my wants.

1. TTC font collection support. This possibly would introduce fontsets.
2. CFF fonts support.
3. (...) a little gap for grouping less important things (...)
4. General fontset support.
5. (...) a bigger gap here (...)
6. Stable external Glyph API - in the sense of it being as stable as the rest of the API, just not being a hidden internal detail.

Kind regards!