How does RoboFont compile .ttf fonts?
not sure I understand what you mean.
The OT features and naming tables are compiled by FDK and merged back in a ttf file with the converted glyph with cubic curves.
Interesting question ... Do you use your own routines for outline conversion to quadratic beziers, or are there existing libraries perhaps in the FDK?
In RoboFont there are two possible ways to convert outlines:
(see Spline Conversion http://doc.robofont.com/documentation/workspace/font-info/robofont/)
One is 100% accurate to the outlines, which mean points will be added
the other one is 100% accurate to the amounts of points, but the changes to the curve is minor, handy for interpolation afterwards
Sorry. I meant: what is RF's path for generating .ttf fonts?
For .otf fonts the path is something simple like: RF UFO > ufo2dfk > FDK generates .otf
For .ttf fonts the path is something like: RF UFO > ???
(eg. RF-python script + ttLib > FDK > RF-python script + ttLib > .ttf ?)
the ttf "path":
RF UFO > internal ttf compiler on top of ufo2fdk > glyph data .ttf > fdk for some tables > .ttf