I’m not sure if I understand all of the involved parts/tables correctly yet, thus my question.
Is it possible to build an axis that adjusts the tracking of a font by just using the HVAR table?
I have built a variable font from two differently tracked base TTFs using varLib, tracked 0 and 60 font units, and it seems that a delta corresponding to the half tracking value (30) is stored for every point of every glyph in the gvar table (except the phantom points, which are adjusted with different values (0 respectively 60, the tracking change) as they should be), which seems awfully inefficient. Is there a way around this?
There's also the much simpler ‘trak’ table by Apple, but it’s not a part of the OTVar spec