Customising note heads
There are two things you need to do to create arbitrary noteheads:
1. change the NoteHead stencil to the text-interface.
2. define the text attribute of the NoteHead. It accepts any markup. The easiest thing to do is to simply call a musicglyph, as in this example.
\version "2.24.0"
%% http://lsr.di.unimi.it/LSR/Item?id=475
%LSR This snippet was contributed by Victor Adan
headCircle = {
\once \override NoteHead.stencil = #ly:text-interface::print
\once \override NoteHead.text = #(markup #:musicglyph "scripts.flageolet" ) }
headPlus = {
\once \override NoteHead.stencil = #ly:text-interface::print
\once \override NoteHead.text = #(markup #:musicglyph "scripts.stopped") }
{
\headCircle
c'4
\headPlus
d'4
% normal
e'4
}