Tone cluster

[Pierre Perol-Schneider]

Hi All,

I have this function to make a tone cluster:

%%%%
\version "2.20.0"

toneCluster = #(define-music-function
                 (note1 note2) (ly:music? ly:music?)
                   #{
                      <<
                        { #note1 }
                        {
                          \once\override NoteHead.stem-attachment = #'(0 .
0)
                          \once\override Stem.length = #14 % <= Manually
set.
                          \once\override Stem.thickness = #7
                          #note2
                        }
                      >>
                   #})

% Test:
{
  a' \toneCluster a a'' a' \toneCluster a cis''''
}
%%%%

How could I set the stem length automagically according to the pitch
difference?

Cheers,
Pierre