Old style figures for Brahmic scripts

Hey friends!
I’m developing a typeface that includes besides latin, thai and khmer notations system. My goal is to create a coherent font between south-east asian cultures. i created old style figures for latin, but i’d also create old style figures for thai and khmer. actually they don’t exist in reality, but are completely feasible to exist. i was wondering if indesign or other programs with opentype compatibilities would recognise thai or khmer numbers with the «.osf»-suffix and display them if this function is used or if this function is only possible for arabic numerals.
i appreciate your help.
Thanks,
Bastian

I think this should work. InDesign should simply process any OT substitutions in the onum feature, whatever script the glyphs happen to be. Glyphs would build this feature automatically if the .onum suffix is used.

I’ve also been including superscript numerals and fractions for Burmese and Thai, so I’d imagine the same could be done for Khmer if you fancy it. Good luck!

Thanks for your reply, i think it is a helpful remark about the supuerscript numerals. it sounds obvious yet I wanted to be sure before i do efforts!