\include "english.ly"

%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 1 0) (x11-color 'orange))
    (cons (ly:make-pitch 0 2 0) (x11-color 'yellow))
    (cons (ly:make-pitch 0 3 0) (x11-color 'green))
    (cons (ly:make-pitch 0 4 0) (x11-color 'turquoise))
    (cons (ly:make-pitch 0 5 0) (x11-color 'blue))
    (cons (ly:make-pitch 0 6 0) (x11-color 'plum))

    (cons (ly:make-pitch 0 6 -1/2) (x11-color 'blue))
    (cons (ly:make-pitch 0 3 1/2) (x11-color 'green))))

%    (cons (ly:make-pitch 0 0 1/2) (x11-color 'red))
%    (cons (ly:make-pitch 0 1 -1/2) (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 4 1/2) (x11-color 'red))
%    (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 3 1/2) (x11-color 'green))
%    (cons (ly:make-pitch 0 4 -1/2) (x11-color 'blue))
%    (cons (ly:make-pitch 0 5 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 (event-cause grob) 'pitch)))

#(set-default-paper-size "a4" 'landscape)
#(set-global-staff-size 52)

\score {
  \new Staff \relative c' {
    \override NoteHead #'color = #color-notehead
    \easyHeadsOn
    \time 3/4
    \key f \major
    \partial 8
    c8 | f8. f16 f4. g8 | a8. a16 a4. a8 | g a bf4 e, | g f r8 c |
    \break
    f8. f16 f4. g8 | a8. a16 a4.  a8 | g a bf4 e, | g f r8 c' |
    \break
    c a d4. c8 | c bf bf4. bf8 | bf g c4. bf8 | bf g c4. bf8 | bf a a4 c, |
    \break
    f8. f16 f4. g8 | a8. a16 a4. a8 | g a bf4 e, | g f4. \bar "||"
   }
}