Question

lilypond can color notes in a arbitrary way using

\override NoteHead #'color = #red c

with the default color is black. But I like to color all notes by pitch, so that my kids can more easily learn to recognize the notes as the c, d, e, f, … are associated with its own color. The above allows me to do this, but is rather verbose.

Is there a shortcut, macros of some sort, that allow me to do something along the lines of:

redc greend bluee

or even overwriting the default colors for each note by pitch so that I can even simply do:

c d e

and have each of them have a different color?

Answer 1

There is an example for this in the snippets:

%Association list of pitches to colors.
#(define color-mapping
  (list
    (cons (ly:make-pitch 0 0 0) (x11-color 'red))
    (cons (ly:make-pitch 0 0 1/2) (x11-color 'green))
    (cons (ly:make-pitch 0 1 -1/2) (x11-color 'green))
    (cons (ly:make-pitch 0 2 0) (x11-color 'red))
    (cons (ly:make-pitch 0 2 1/2) (x11-color 'green))
    (cons (ly:make-pitch 0 3 -1/2) (x11-color 'red))
    (cons (ly:make-pitch 0 3 0) (x11-color 'green))
    (cons (ly:make-pitch 0 4 1/2) (x11-color 'red))
    (cons (ly:make-pitch 0 5 0) (x11-color 'green))
    (cons (ly:make-pitch 0 5 -1/2) (x11-color 'red))
    (cons (ly:make-pitch 0 6 1/2) (x11-color 'red))
    (cons (ly:make-pitch 0 1 0) (x11-color 'blue))
    (cons (ly:make-pitch 0 3 1/2) (x11-color 'blue))
    (cons (ly:make-pitch 0 4 -1/2) (x11-color 'blue))
    (cons (ly:make-pitch 0 5 1/2) (x11-color 'blue))
    (cons (ly:make-pitch 0 6 -1/2) (x11-color 'blue))
    ))

%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-color pitch)
  (let ((color (assoc pitch color-mapping pitch-equals?)))
    (if color
      (cdr color))))

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

\score {
  \new Staff \relative c' {
    \override NoteHead #'color = #color-notehead
    c8 b d dis ees f g aes
  }
}