by encoding as integers all float values that have no decimal portion.
This optimization is expected to reduce the file size of CFF2 fonts that have intermediate masters.
Related to https://github.com/adobe-type-tools/afdko/issues/444
Many thanks to @cjchapman for the help on the fixed point math
I'm also unimpressed by the copy-pasted bounds logic in hhea and vhea,
and the fact that that's coded in there instead of calling a function
on CFF / glyf tables respectively.
