Opentype code to change ligatures based on diacritics marks

moizngp · January 16, 2020, 9:33am

Hello,

I noticed this feature in “Adobe Naskh Medium” font, where a ligature changes depending on the above or below diacritics marks.

Please suggest possible opentype substitution code.
Please refer the image for an example.
Thanks and regards.

mekkablue · January 16, 2020, 11:03am

You would need to write code without the IgnoreMarks flag, best in a separate lookup before the flag. And then it’s just straight-forward substitutions.