Here’s one problem with 4-values positioning:
I thought of using one set of small figures and GPOSing them for superior/inferiors and fractions. For italics, when you change Y you also need to change X. It works in static exports, but not in variable (not even in Gauntlet).
OTF:
Variable:
Feature:
lookup subscript {
sub @Figures by @Dnom;
} subscript;
#if VARIABE
pos @Dnom <$subscriptX -200 0 0 (ital:14) $subscriptX -200 0 0>;
#else
pos @Dnom <$subscriptX -200 0 0>;
#endif
File:
Variable GPOS test.glyphs (12.5 KB)