Support global metrics for vertical typesetting
anthrotype opened this issue · comments
we currently only set the global metrics for horizontal layout. We should add support for vertical layout fonts by building a vhea table, and also store the corresponding variable global vertical metrics tag in the MVAR table (e.g. vertical ascender, descender, line gap, vertical caret slope).
A VORG table is only needed for CFF and we currently only build TrueType-flavored variable fonts.