I have used class kerning before, but just ran into a problem I had not encountered before.
All my previous classes were simple with both sides being the same. I watched a video on class kerning this evening and he explained also how to do class kerning on one side only.
In this family of typefaces that I'm working on I had a handful of alternate letters and some ligatures that I had under the dlig feature. Previous to this I had not generated a kern feature since I knew I would be adding more classes.
Anyway… when I generated the kern feature on the first font with the new one-side-only kerning classes and then compiled it in the OT panel I got a whole list of warnings.
[WARNING] Start of new pair positioning subtable; some pairs may never be accessed: [A Adieresis Aring Agrave Atilde Acircumflex Aacute A.alt Amacron Abreve Aogonek] [T T_H T_H_E T_T T_T_Y T_U T_V T_W T_Y]
It still compiles and the kerning seems to work as it should in the metrics window. When I deleted the new classes, deleted the kern feature and regenerated it without the new classes it was fine. Anybody know what's going on with that?
Here is a sample of a left-side only kerning class:
_Tleftside: T' T_H T_H_E T_T T_T_Y T_U T_V T_W T_Y
I then checked the box to the right side.