@genleung_lan the problem i think is that you are trying to allocate too many glyphs. Textures in desktop allow for much bigger sizes but in the raspberry pi they are limited to a smaller size (don’t know exactly how much right now)
Instead of trying to allocate all of CJK + Latin in one font you can try to load only CJKUnified in one font and then another for latin.
You can also use:
getStringTexture to get a specific text in a texture which will only need to load the specific characters you are asking for. Don’t use this every frame though since it will be slow. But you can pre-allocate the texts in setup and use them after. Also aligning text with this method can be tricky since the position will be from the top left corner instead of the baseline of the text.
The solution for this is to allocate more than one texture per font if needed and create an index to know in which texture each character, we might include it for next release
By now i’ve included a check in ofTruetypeFont to show an error in case the texture needed is bigger than the maximum supported in each platform