Is there a way to control numbers kerning when changing the writing direction? Please note that I’m designing an Arabic font using the Hindi characters for all the numerics.
Correct kerning for Arabic numbers. Writing direction is left to right.
Wrong kerning for Arabic numbers. Writing direction is right to left.
It will be the same result if I use the characters you mentioned (one-ar, etc.) (and which I already did, but the examples here shows the Latin characters), I can kern the numbers for either left to right, or right to left, but not for both directions!
Numbers in Arabic are always written left-to-right. So you should only kern them in LTR mode. The RTL mode would indeed show wrong kerning. I’m not sure if it is possible to have kerning between arabic numbers and letters.
There was a bug with the mapping of the classes to scripts that put the arabic numbers in the wrong lookup. I fixed that, so the kerning of arabic numbers should work now.