I’m working on an application that accepts text in English and performs transliteration with a custom 3rd party API into an Indic language (one of several that are supported). The application is targeted at Windows XP/7 and Ubuntu.
We use a custom input method that loads the required Indic font, and uses it render text. Also, the user can correct the transliterated text by typing in English and pressing space (similar to how Google Transliterate works).
The problem is that with certain Indic fonts, typing in English shows up empty box characters (even though the actual characters typed are detected and transliterated accordingly).
I have used the ttf-indic-fonts-0.5.0 font pack that comes with Ubuntu, and was able to substitute some of them. For the others, if I copy the corresponding font from Windows (I’m developing this on Windows 7) then all problems are solved.
However, we cannot redistribute Windows fonts with our application and want an open alternative.
Other than trying to find a substitute font, is there anything else that we’re doing wrong, or need to check, to make sure that English characters can be typed in a JTextField when an Indic font is being used?
As an example – from the Ubuntu package mentioned above, the lohit_pa.ttf font for Punjabi has this problem. If I copy the default Windows font for Punjabi (raavi.ttf) then it works fine.
I found a solution to the problem. I installed the fonts on Windows (open the font, click install) and browsed the contents using Character Map. These fonts only have glyphs for the language in question, not English.
I used FontForge to merge the 2 fonts. (Fontforge’s author doesn’t provide binaries anymore – but if you have access to Ubuntu you can install it from the repository. No such luck if you only have Windows).
After this, I’m able to type in English again.