cmuratori
I don't believe that actually requires any changes to the font system. That's more about parsing the characters. Although really you don't even have to do that, because you could just choose to store the text for the game _pre converted_, couldn't you? Eg., the right glyph choice is just baked into the strings you're displaying for that language?
- Casey
For Arabic, yes, because the variant forms have their own codepoints.
However, some scripts have combining forms that don't have codepoints for precomposed glyphs.
https://en.wikipedia.org/wiki/Complex_text_layout
One possible option is just to prebake entire strings and let Windows sort it out. Since full Unicode is only really necessary for UI, there's probably some finite set of strings that would be needed for any given language.
EDIT:
Of course, the market for games in Thai may or may not be large enough to justify the extra effort and complexity.