> If I don¡¦t use the Unicode values of Arabic presentation form B then how > will my display know which particular glyph to display? using the Unicode > values of presentation form B makes this easier but then the original > Unicode changes. > > I am sorry but I am a bit confused with what to display and what Unicode to > store, your comments would be really help full.
You should consider this two different problems. 1. What unicode to store. To see this you might want to have a look at the examples which come with S C UniPad from http://www.unipad.org , especially udhr_ara.utx . This is good unicode. Look what char values they use for the letters. If they don't extensively use presentation form B then neither should you. Look how it displays on your display module. If it does not display well then you know that the display module is the problem, that you can expect the same errors in your own text, and that you should _not_ try to repair them by changeing the storage format. 2. How to display it. If your display module cannot do automatic contextual shaping, if it needs glyph numbers instead of char numbers then you should find a way to send it something different from what is stored, _without_ changeing the storage. I would say then that that display module cannot handle unicode input and that what you send it is not unicode.