Using TMPro Font Assets for non-western languages

Hi,

Sorry for the delay in answering, I have been sick these last couple days and couldn't do much support Luckily I'm feeling better now and back at full support

1. Do I do something wrong in the first place on how I approach Font Asset creation? Again, I just paste all text in all languages into the Font Asset Creator. I switch between the two ttfs to create individual font assets to use for each language.

Normally, you would like to include in a given font only the characters that you use. If you are going to use different TMPro fonts for some languages (recommended approach), then those should only include the characters for that language (not all characters for every language)

What I normally do, is to create a font for latin languages and separated fonts for other languages with a completely different character set (Rusian, Chinese, Korean, etc)
To generate each font, I go to the spreadsheet and get all texts for the specific language (e.g. only the Korean column) and run a script to remove duplicated characters. That way I end up with a string containing all characters used for that language, and only those. Alternatively, I also add the 0..9 numbers and some common signs if they are used in your UI.

Then, I take that string and use it to generate the font using the Font Asset Creator. You should pay special attention to the ttf you are going to use for that operation, given that as you described, some ttf don't contain all needed characters.

Therefore, after generating the font atlas, I double check that all characters were generated (TMPro also reports the number of characters) so that if the initial string had 50 characters, the number of characters in the generated atlas, has to be 50 as well.
If there are less than 50, it means that the ttf you used doesn't have those characters, so you should use another ttf (e.g. Arial)

Using this approach (not baking ALL characters from ALL languages) into a single atlas, will allow you to use more texture space for the Signal Distance Field that TMPro uses, therefore your text's quality will be higher without using more texture space.

2. Or is it just a problem that I used the wrong ttf font as source? I thought it was pretty hard to find (free) fonts in the first place or I did not look for the right places. Is there a standard font which supports western and CJK which "just works" and will also show numbers in the CJK-generated Font Assets?

Yes, as you are saying, some ttf may not contain the full UNICODE spectrum, so some character sets will be missing.
Most font download web sites show which character sets the font has, so may sure to check those before getting them.

One way to be safe is to use a stylized font for your latin languages (e.g. Droid Sand) and the Arial font for chinese, korean, etc. The default Arial font comes with most if not all character sets.

Hope that helps,
Frank