Nice! I'd built something similar to make fonts for the Adafruit GFX library. http://aravind.rs/fruitfont/

Its export format is C code that defines GFXGlyph and GFXFont structs.

Doesn't work well on mobile and multiple size/style variants doesn't work yet. This was mostly the result of yak shaving after I set out to make a watch face for my SQFMI Watchy.