I'm trying to understan the logic of aalt applied to numbers.
For instance, in PremierePro I find:
one (1) | one.oldstyle one.numerator one.denominator one.superior one.inferior(₁) one.taboldstyle one.fitted<br>one.fitted | one.oldstyle one(1)<br>one.oldstyle | one(1) one.fitted one.taboldstyle<br>one.taboldstyle | one(1) one.oldstyle
Now:
1) what determines the fact that in certain cases one(1) is choosen as the first substitution, in other ones as the second substitution?
2) why in one.fitted there isn't one.taboldstyle? Which is the reason?
Thank you
Comments
If you want all possibilities to be included and control the order, you can write it that way yourself. It doesn't have to be implemented by listing all the features that do substitutions. That's just how it's often done.
There is no built-in mechanism to store names of classes in an OT font, that is purely on the font editor side. So that is lost when you compile to OTF or TTF.
The nature of classes themselves is tricky. Older editors maintain the classes users create, but at the potential cost of a larger compiled font, and even compile failure. FontLab VI uses KLTF optimization to make a smaller output OTF/TTF font (avoiding kern subtable overflow). But this means that the organization of the kerning may be different than what the user put in. The font functions the same, but you can't necessarily open that font back up and have the same class kern setup you started with.