rewriting ancient notation

[Han-Wen Nienhuys]

Juergen Reuter escreveu:

> Actually, the above approach will not work without further modification:
>
> Currently, note-heads-engraver.cc listens for note events and creates 
> NoteHead grobs; the ligature engraver "takes over" these note heads and 
> manipulates them.  To follow the above approach, I would have to make 
> the note heads engraver stop producing note head grobs (and instead let 
> the ligature engraver produce LigatureHead grobs).  But how can I 
> achieve this?  Removing the note heads engraver completetly from its 
> context is no option, since both usual note heads as well as ligatures 
> have to appear in the same context.
>
> So, how can I signal the note heads engraver that a ligature is in 
> process and that it should stop producing note heads?

the easiest method I can think of is the following:

Have the Ligature_head_engraver acknowledge note_head grobs. Upon 
catching them, suicide the note head and create a LigatureHead. Another 
option is to add a new property for temporarily disabling normal noteheads.

however, I think it's out of the scope right now: first the ligatures 
have to work correctly without presence of a note_head_engraver. If that 
is the case, then we can figure out how to get both out of each other's 
way.

--

Han-Wen Nienhuys - address@hidden - http://www.xs4all.nl/~hanwen

LilyPond Software Design
 -- Code for Music Notation
http://www.lilypond-design.com