Generate pitches between pitches

[Paolo Prete]

Hello,
given two pitches, for example: c' and c'',   is there a way to automatically 
generate all the pitches between them? In three different ways:
1) all the "white keys" between them:   d' e' f' g' a' b'2) all the "black 
keys" between them:   des' ees' ges' aes' bes'3) all the pitches:  des' d' ees' 
e' f' ges' g' aes' a' bes' b'
This feature would be very useful for simulating (piano) glissandos with MIDI.
thanks.