Ikebana is a project mainly written in Python, it's free.
GTK mustic notation rendering hack, using lilypond as rendering backend.
This is Ikebana, a simple GUI for entering LilyPond music. It uses LilyPond 2.13.29
USAGE:
ln emmentaler-20.otf ~/.fonts/
lilypond -dbackend=socket server.ly &
python ikebana.py
KEYS
a..g pitch A..G add chord pitch up,down move between chord notes , ' octave r rest space enter note left,right move . dot
alteration up/down
backspace delete note Ctrl+@ double flat @ flat ! natural x double sharp
Shift+up,down change pitch ~ arpeggio
CAVEAT
This is a proof-of-concept demo. Don't expect features, support, maintenance.