input/lsr/transposing-pitches-with-minimum-accidentals-smart-transpose.ly

   1 %% Do not edit this file; it is auto-generated from input/new
   2 %% This file is in the public domain.
   3 %% Note: this file works from version 2.12.0
   4 \version "2.13.1"
   5 \header {
   6 doctitlees = "Transportar música con el menor número de alteraciones"
   7 texidoces = "
   8 Este ejemplo utiliza código de Scheme para forzar las
   9 modificaciones enarmónicas de las notas, y así tener el menor
  10 número de alteraciones accidentales. En este caso se aplican las
  11 siguientes reglas:
  12
  13 @itemize
  14 @item
  15 Se quitan las dobles alteraciones
  16
  17 @item
  18 Si sostenido -> Do
  19
  20 @item
  21 Mi sistenido -> Fa
  22
  23 @item
  24 Do bemol -> Si
  25
  26 @item
  27 Fa bemol -> Mi
  28
  29 @end itemize
  30
  31 De esta forma se selecciona el mayor número de notas enarmónicas
  32 naturales.
  33
  34 "
  35
  36 doctitlede = "Noten mit minimaler Anzahl an Versetzungszeichen transponieren."
  37
  38 texidocde = "Dieses Beispiel benutzt Scheme-Code, um enharmonische
  39 Verwechslungen für Noten zu erzwingen, damit nur eine minimale Anzahl
  40 an Versetzungszeichen ausgegeben wird.  In diesem Fall gelten die
  41 folgenden Regeln:
  42
  43 @itemize
  44 @item
  45 Doppelte Versetzungszeichen sollen entfernt werden
  46
  47 @item
  48 His -> C
  49
  50 @item
  51 Eis -> F
  52
  53 @item
  54 Ces -> B
  55
  56 @item
  57 Fes -> E
  58
  59 @end itemize
  60
  61 Auf diese Art werden am meisten natürliche Tonhöhen als enharmonische
  62 Variante gewählt.
  63 "
  64
  65
  66   lsrtags = "pitches"
  67   texidoc = "This example uses some Scheme code to enforce enharmonic
  68 modifications for notes in order to have the minimum number of
  69 accidentals.  In this case, the following rules apply:
  70
  71 @itemize
  72 @item
  73 Double accidentals should be removed
  74
  75 @item
  76 B sharp -> C
  77
  78 @item
  79 E sharp -> F
  80
  81 @item
  82 C flat -> B
  83
  84 @item
  85 F flat -> E
  86
  87 @end itemize
  88
  89 In this manner, the most natural enharmonic notes are chosen.
  90 "
  91   doctitle = "Transposing music with minimum accidentals"
  92 } % begin verbatim
  93
  94
  95 #(define  (naturalize-pitch p)
  96   (let* ((o (ly:pitch-octave p))
  97          (a (* 4 (ly:pitch-alteration p)))
  98          ; alteration, a, in quarter tone steps,
  99          ; for historical reasons
 100          (n (ly:pitch-notename p)))
 101     (cond
 102      ((and (> a 1) (or (eq? n 6) (eq? n 2)))
 103       (set! a (- a 2))
 104       (set! n (+ n 1)))
 105      ((and (< a -1) (or (eq? n 0) (eq? n 3)))
 106       (set! a (+ a 2))
 107       (set! n (- n 1))))
 108     (cond
 109      ((> a 2) (set! a (- a 4)) (set! n (+ n 1)))
 110      ((< a -2) (set! a (+ a 4)) (set! n (- n 1))))
 111     (if (< n 0) (begin (set! o (- o 1)) (set! n (+ n 7))))
 112     (if (> n 6) (begin (set! o (+ o 1)) (set! n (- n 7))))
 113     (ly:make-pitch o n (/ a 4))))
 114
 115 #(define (naturalize music)
 116   (let* ((es (ly:music-property music 'elements))
 117          (e (ly:music-property music 'element))
 118          (p (ly:music-property music 'pitch)))
 119     (if (pair? es)
 120        (ly:music-set-property!
 121          music 'elements
 122          (map (lambda (x) (naturalize x)) es)))
 123     (if (ly:music? e)
 124        (ly:music-set-property!
 125          music 'element
 126          (naturalize e)))
 127     (if (ly:pitch? p)
 128        (begin
 129          (set! p (naturalize-pitch p))
 130          (ly:music-set-property! music 'pitch p)))
 131     music))
 132
 133 naturalizeMusic =
 134 #(define-music-function (parser location m)
 135   (ly:music?)
 136   (naturalize m))
 137
 138 music = \relative c' { c4 d e g }
 139
 140 \score {
 141   \new Staff {
 142     \transpose c ais { \music }
 143     \naturalizeMusic \transpose c ais { \music }
 144     \transpose c deses { \music }
 145     \naturalizeMusic \transpose c deses { \music }
 146   }
 147   \layout { }
 148 }