Applying note head styles (shapes) based on pitch or note name

The shapeNoteStyles property can be used to set custom note head styles for each step of the scale (as set by the key signature or the “tonic” property). The note head style you designate for G gets also used for G# and Gb, as in shape note notation.

The method used in this snippet lets you assign custom note heads based on a note’s pitch or full name to get different note heads for naturals, sharps, and flats, for example – here, sharp and flat notes are given a square note head shape.

The code is based on the snippet Coloring notes depending on their pitch. See also Applying note head styles depending on the step of the scale.

\version "2.24"

% Association list of pitches to note head styles.
% Grouped by pitch. Defaults: 0 is C, 1 is D, ... 6 is B.
#(define style-mapping
   (list
    (cons (ly:make-pitch 0 6 SHARP) 'default)
    (cons (ly:make-pitch 0 0 NATURAL) 'default)
    (cons (ly:make-pitch 0 1 DOUBLE-FLAT) 'default)

    (cons (ly:make-pitch 0 6 DOUBLE-SHARP) 'la)
    (cons (ly:make-pitch 0 0 SHARP) 'la)
    (cons (ly:make-pitch 0 1 FLAT) 'la)

    (cons (ly:make-pitch 0 0 DOUBLE-SHARP) 'default)
    (cons (ly:make-pitch 0 1 NATURAL) 'default)
    (cons (ly:make-pitch 0 2 DOUBLE-FLAT) 'default)

    (cons (ly:make-pitch 0 1 SHARP) 'la)
    (cons (ly:make-pitch 0 2 FLAT) 'la)
    (cons (ly:make-pitch 0 3 DOUBLE-FLAT) 'la)

    (cons (ly:make-pitch 0 1 DOUBLE-SHARP) 'default)
    (cons (ly:make-pitch 0 2 NATURAL) 'default)
    (cons (ly:make-pitch 0 3 FLAT) 'default)

    (cons (ly:make-pitch 0 2 SHARP) 'default)
    (cons (ly:make-pitch 0 3 NATURAL) 'default)
    (cons (ly:make-pitch 0 4 DOUBLE-FLAT) 'default)

    (cons (ly:make-pitch 0 2 DOUBLE-SHARP) 'la)
    (cons (ly:make-pitch 0 3 SHARP) 'la)    
    (cons (ly:make-pitch 0 4 FLAT) 'la)

    (cons (ly:make-pitch 0 3 DOUBLE-SHARP) 'default)
    (cons (ly:make-pitch 0 4 NATURAL) 'default)
    (cons (ly:make-pitch 0 5 DOUBLE-FLAT) 'default)

    (cons (ly:make-pitch 0 4 SHARP) 'la)
    (cons (ly:make-pitch 0 5 FLAT) 'la)

    (cons (ly:make-pitch 0 4 DOUBLE-SHARP) 'default)
    (cons (ly:make-pitch 0 5 NATURAL) 'default)
    (cons (ly:make-pitch 0 6 DOUBLE-FLAT) 'default)

    (cons (ly:make-pitch 0 5 SHARP) 'la)
    (cons (ly:make-pitch 0 6 FLAT) 'la)
    (cons (ly:make-pitch 0 0 DOUBLE-FLAT) 'la)

    (cons (ly:make-pitch 0 5 DOUBLE-SHARP) 'default)
    (cons (ly:make-pitch 0 6 NATURAL) 'default)
    (cons (ly:make-pitch 0 0 FLAT) 'default)))

% Compare pitch and alteration (not octave).
#(define (pitch-equals? p1 p2)
   (and
    (= (ly:pitch-alteration p1) (ly:pitch-alteration p2))
    (= (ly:pitch-notename p1) (ly:pitch-notename p2))))

#(define (pitch-to-style pitch)
   (let ((style (assoc pitch style-mapping pitch-equals?)))
     (if style
         (cdr style))))

#(define (style-notehead grob)
   (pitch-to-style
    (ly:event-property (event-cause grob) 'pitch)))


\score {
  \new Staff \relative c' {
    \override NoteHead.style = #style-notehead
    c2 cis d dis e f fis g gis a ais b c
  }
}