How to generate notes in a scale

[Peter Chubb]

Hi,
        I'm currently trying to get improved MIDI output.  I have a
scheme function that processes articulations like staccato, tenuto,
etc., working now.  But for turns and trills, I need to generate the
notes around a note in the current key.

        Has anyone written a scheme function to do this yet?  for
example, given e return fis (if the current key is g), or given e return f (if
the current key is c)?  I'm a bit stuck, as I can't even work out how 
to get at the current key within a music-function.
--
Dr Peter Chubb  http://www.gelato.unsw.edu.au  peterc AT gelato.unsw.edu.au
http://www.ertos.nicta.com.au           ERTOS within National ICT Australia