Get ASCII Char from Keystroke and modifier?

[Aya Koshigaya]

Hi,

I'm writing a glut-application and need to know what key the user has  
pressed.

if the user hit ALT+n to get a ~ glut gives me the key-code "n" and  
the modifier ALT.. but, is there a way to convert this to ~?
I could write maaaaany if's.. but... I'm not sure if this would be the  
nicest way..

In Windows there's an API function "toAscii" where I can pass the key- 
code + modifier states and get the resulting ASCII Character.
Is there something similar in OSX too?

Preferably in carbon (c++).

Aya~