An update to the situation. As of UE 5.1, there’s a Thai font file bundled with the engine (NotoSansThai.ttf). However, there’s no reference to this font file at all in the engine source code (or at least as far as I can tell), so you will still get a [ท] tofu inside the editor when you type something in Thai in text control or anything.
So it’s safe to say we are a step closer but not there yet.
Now, with the simple code changes I made on the reply above, I can make it display Thai text (almost) properly. Given that I have the font file placed in the right place.
So I’d like to propose to add support for Thai text by adding Thai fonts (and the supporting code) to the UE editor.
** Choice of font **
I’m proposing to use “NotoSansThaiLooped” font, instead of “NotoSansThai”. While the name is very similar, their design are quite different. The main reason why I’d go with NotoSansThaiLooped is it has “loops”. NotoSansThai does not have loops, instead it has slant suggesting that there’s loop there.
Comparing to the non-looped version, the loop helps with legibility of the text, especially on the super small size text (like in UE’s editor). In fact, this is how the proper Thai character should looks like, not the non-looped version. I don’t know why the designer of the NotoSansThai decided not to have loops in the font.
These two fonts are part of the Google’s Noto project and there are fonts from the project that are already in-use by UE so I think it should be fine, licensing-vise.
I’d like to mention that I have talked with Chris Murphy (@HighlySpammable ) and Jack Condon a couple of times when they are here in Bangkok (the last time was the last Monday) about this. This is why I’m resurrecting this thread.
Jack did suggest that the UI font can be changed, but I can’t find where so … if anyone has an idea please let me know.