part combiner

[kristof]

Hi lilyponders.

I am currently orchestrating a piece of music using lilypond for
the notation.  I am using the part-combiner to combine the wind
instruments, but I find it to be unusable for the folowing reasons:

- There are to many changes from solo, a due, etc.  In one bar I have
even 8 changes!  When there is just one rest in the combiner it will
print solo above it.  Obviously there should be at most one change each
bar, and in the ideal case it should remain the same for a melody.  That
would make it easier for a conductor or person reading the score to follow.

- It appears that parts will not be combined when a crescendo or diminuendo
is active.  It should be possible to have an a due part with dynamics.

- Rest can be merged more often.  When there is the same amount of silence
for both instruments, there need only to be one rest, since there can be
no ambiguity about who is not playing.

- It would be nice if the part-combiner could handle voice-crossings
elegantly, for example using a little line to show the direction of the
voice.


I would like to rewrite the part-combiner, but I have a few questions
about doing so:

- How can I get the time signature from the voice?
- How can I analyse a moment (for example to see if it falls withing a
bar)?
- Would it be possible to just change the scheme code (since I like more
writing scheme than C++ ;-) ?
- Will the C++ part of the part-combiner handle dynamics and slurs
gratiously for a due parts or chords?

Thank you for your time reading this large sandwich of questions :)

Kristof Bastiaensen