I'm working on my debut font. Just about to finish standard latin glyph. And I'm thinking to expand it to multilingual. The problem is, I don't understand what glyph/unicode to design in order for my font to support multilingual.
I tried to observe other fonts about multilingual support, and it turns out not every the unicode in latin extended A, B etc. is assigned with some design. In other words, there is some blank unicode in latin extended A, B, etc. So it doesn't help me understand which unicode range shall I design to support multilingual.
Can anybody explain me the unicode range to design in order for my fonts to support multilinguals? Or maybe is there some concept/keywords shall I learn so I can understand about multilingual support?
I recommend using Alphabet Type's Charset Builder to create your character set, it's a fantastic tool.
And then even not always; the Unicode cons. may be planning ahead and consider that if adding support for a glyph x, it could be expected to have to add x+1, x+2 etc. in short order. In such a case, they'd better off choosing a block with plenty of room for future expansion.
Don't bother too much about actual Unicode values (blocks, ranges, or whatever). Look up what characters you need, and only then look up their Unicode values.
Latin Extended A
The missing glyphs with circumflexes are for Esperanto. So research Esperanto and make your own decision. 0138 and 0149 are historical. The Ldots are deprecated and shouldn't be included. Do some research on Ubreve and decide for yourself.
Latin Extended B
If you want to support more African languages for a display typeface, you'll have to do research to figure out what's in use, historical, what's mainly used for textbooks. I've never found a guide explaining this clearly. Oops just noticed I missed the flipped E at 018E. I think you should always include Vietnamese but if you don't want to, you can skip the hooked O and U.
Combining Diacritical marks
Latin Extended Additional
I don't recommend skipping the Vietnamese characters but if you decide to, keep the dotted vowels as other languages require them. Don't forget 1E9E...I usually don't miss that one. You need that for sure.