Marlin supports HD44780 character LCD and 128x64 graphical LCD via U8GLIB. Because of the limitation of HD44780 hardwares, Marlin can only support three character sets for that hardware: Japanese (kana_utf8), Russian/Cyrillic (ru), or Western (Roman characters)
For the graphical LCD modules, there's far less limitation. Users and language maintainers can easily change the language translation strings when saved with UTF-8 encoding. The only extra step is to regenerate the font data from an existing BDF font file.
You need to add a language header file `language_xx.h`, replacing xx with the language/country code. (e.g., "en" for English). You can start with a existing language file by copying it to a new location:
This step gathers the glyphs used in the language file from a 9pt bitmap font and saves the data in a language_data_xx.h file. So the font used for conversion should contain all the characters in your language file.
You may need to use a different font to support your own language, because the default 9pt font is not complete. (You may also support them by adding the missing glyphs to the font.)
After you've prepared your font, specify the font file path as an argument to `genallfont.sh`, so that the font used for your language is your new font. For example, if your font is named `newfont.bdf` run the following command:
The tool and the language engine can be easily updated. Since it uses common bitmap font files and UTF-8 text, the maintainer needs to confirm that the font contains the glyphs in the language files.
At this time, the font file `marlin-6x12-3.bdf` is used to generate the font data. It combines all of Marlin's ISO10646-1 fonts and the WQY 9pt bitmap font.