Advice regarding .isol .fina .medi .init

I’m doing a script typeface using .isol, .fina, .medi and .init.

First the kerning, as the letter shapes are slightly different and I plan on doing western, central and south eastern glyphs what is the best way to setup kerning groups?

Should I set 4 kerning groups for each letter i.e.


Then create say

aacute.isol / kerning group = a.isol
aacute.fina / kerning group = a.fina
aacute.medi / kerning group = a.medi
aacute.init / kerning group = a.init

Is that the best way to do it, or is there a smarter way. Its a lot of kerning, but would be worth it.

One other question do I even need the .medi glyph? I’m using the script build positional calt feature
can I just use the regular glyph for the .medi? will that work as at the moment my regular glyph is not
used at all?

Any help/advice much appriciated

That depends on your design. Also, I guess that e.g. a.fina can share the left group with a.

Do you need all 4 positions as variants of the default? I suggest one of them should be the regular one, like the medial forms, so you would have:

a (medial shape)

Thanks for the input, this is still work in progress, when you told me about the .isol, .fina, etc in a previouse question I thought I’d make use of them.

So just to clarify I don’t need .medi the default character is medi. I can remove those from my font.

Will the diacritics just need those .isol .fina and .init extra glyphs too? Sorry for all the questions.

If you generate aacute.isol, it will prefer a.isol above a if available. So, yes.