View source for Score for diatonic accordion

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  This example relies on undocumented editor macros (which should probably be implemented as Scheme functions so that the music has to be input only once).  Additionally, it seems that there are no other examples in the internet that use the suggested template layout; I wonder whether the used format is an ad-hoc invention (WL).
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A template to write a score for a diatonic accordion.

* There is a horizontal staff indicating if the accordion must be pushed (thick line) or pulled (thin line).
* There is a small rhythmic staff with lyrics that describes the bass buttons to press. The bar lines are made from gridlines.
* The tabulator staff for diatonic accordions shows the geographic position of the buttons and not (as for every other instrument) the pitch of the notes; the keys on the melody side of the accordion are placed in three columns and about 12 rows.

In the tabulator staff notation the outermost column is described with notes between lines, the innermost column is described with notes between lines and a cross as accidental, and the middle column is described with notes on a line, whereby the row in the middle is represented on the middle line in the staff.

Some words to transpose piano notes to the diatonic accordion:

# Every diatonic accordion is built for some keys only (for example, for the keys of C major and F major), so it is important to transpose a piano melody to match one of these keys. Transpose the source code, not only the output because this code is required later on to translate it once more to the tabulator staff. This can be done with the command <code>displayLilyMusic</code>.
# You have to alternate the push- and pull-direction of the accordion regularly. If the player has a too long part to pull the accordion gets broken. On the other hand, some harmonies are only available in one direction. Considering this, decide which parts of the melody are the push-parts and which the pull-parts.
# For each pull- or push-part translate the piano notes to the according tabulature representation.

<lilypond version="2.24">
verse = \lyricmode { Wie gross bist du! Wie gross bist du! }

harmonies = \new ChordNames \chordmode {
  \germanChords
  \set chordChanges = ##t
  bes8 bes8 bes8
  es2 f
  bes1
}

NoStem = { \hide Stem }
NoNoteHead = \hide NoteHead
ZeroBeam = \override Beam.positions = #'(0 . 0)

staffTabLine = \new Staff \with {
  \remove "Time_signature_engraver"
  \remove "Clef_engraver"
} {
  \override Staff.StaffSymbol.line-positions = #'(0)
  % Shows one horizontal line. The vertical line 
  %  (simulating a bar-line) is simulated with a gridline
  \set Staff.midiInstrument = #"choir aahs"
  \key c \major
  \relative c''
  {
    % disable the following line to see the noteheads while writing the song
    \NoNoteHead
    \override NoteHead.no-ledgers = ##t

    % The beam between 8th-notes is used to draw the push-line
    %How to fast write the push-lines:
    %  1. write repeatedly 'c c c c c c c c |' for the whole length of the song
    %  2. uncomment the line \NoNoteHead
    %  3. compile
    %  4. Mark the positions on which push/pull changes.
    %     In the score-picture click on the position 
    %        the push- or pull-part starts
    %           (on the noteHead, the cursor will change to a hand-icon).
    %     The cursor in the source code will jump just at this position.
    %   a) If a push-part starts there, replace the 'c' by an 'e['
    %   b) If a pull-part starts there, replace the 'c' by an 's'
    %  5. Switch into 'overwrite-mode' by pressing the 'ins' key.
    %  6. For the pull-parts overwrite the 'c' with 's'
    %  7. For every push-part replace the last 'c' with 'e]'
    %        8. Switch into 'insert-mode' again
    %  9. At last it should look like e.g.
    %        (s s e[ c | c c c c c c c c | c c c c c c e] s s)
    % 10. re-enable the line \NoNoteHead
    \autoBeamOff
    \ZeroBeam
    s8 s s e[ c c c c c c e] | s s s s s
  }
}

% Accordion melody in tabulator score
% 1. Place a copy of the piano melody below
% 2. Separate piano melody into pull- and push-parts
%      according to the staffTabLine you've already made
% 3. For each line: Double the line. Remark the 1st one 
%      (Keeps unchanged as reference) and then change the second
%      line using the transformation paper
%    or the macros 'conv2diaton push.bsh' and 'conv2diaton pull.bsh'
% Tips:
% - In jEdit Search & Replace mark the Option 'Keep Dialog'

AccordionTabTwoCBesDur = {
  % pull 1
  %<f' bes'>8 <f' a'>8 <d' bes'>8 |
  <g'' a''>8 <g'' b''>8 <e'' a''>8 |
  % push 2
  %<g' c''>4 <f' d''> <g' ees''> <f' a'> |
  <g'' a''>4 <d'' eisis''> <g'' bisis''> <d'' f''> |
  % pull 3
  % <f' bes'>2 r8 }
  <g'' a''>2 r8 }

AccordionTab= { \dynamicUp
  % 1. Place a copy of the piano melody above
  % 2. Separate piano melody into pull- and push-parts
  %      according to the staffTabLine you've already made
  % 3. For each line: Double the line. Remark the 1st one
  %      (Keeps unchanged as reference) and then
  %      change the second line using the transformation paper
  % Tips:
  % - In jEdit Search & Replace mark the Option 'Keep Dialog'
  % -
  \AccordionTabTwoCBesDur
}

\layout {
  \context {
    \Score
    % The vertical line (simulating a bar-line) in
    % the staffBassRhythm is a gridline
    \consists "Grid_line_span_engraver"
  }
  \context {
    \Staff
    \consists "Grid_point_engraver"
    gridInterval = #(ly:make-moment 4/4) % 4/4 - tact. How many beats per bar
    % The following line has to be adjusted O-F-T-E-N.
    \override GridPoint.Y-extent = #'(-2 . -21)
  }
  \context {
    \ChoirStaff
    \remove "System_start_delimiter_engraver"
  }
}

staffVoice = \new Staff = astaffvoice  {
  \time 4/4
  \set Staff.instrumentName = "Voice"
  \set Staff.midiInstrument = "voice oohs"
  \key bes \major
  \partial 8*3
  \clef treble
  {
    \context Voice = "melodyVoi"
    {
      <f' bes'>8 <f' a'>8 <d' bes'>8 |
      <g' c''>4 <f' d''> <g' es''> <f' a'> |
      <f' bes'>2 r8
    }
    \bar "|."
  }
}

staffAccordionMel =
\new Staff  \with { \remove "Clef_engraver" } {
  \accidentalStyle forget %Set the accidentals (Vorzeichen) for each note,
  %do not remember them for the rest of the measure.
  \time 4/4
  \set Staff.instrumentName="Accordion"
  \set Staff.midiInstrument="voice oohs"
  \key c \major
  \clef treble
  { \AccordionTab \bar "|." }
}

AltOn =
#(define-music-function (mag) (number?)
  #{ \override Stem.length = #(* 7.0 mag)
      \override NoteHead.font-size =
#(inexact->exact (* (/ 6.0 (log 2.0)) (log mag))) #})

AltOff = {
  \revert Stem.length
  \revert NoteHead.font-size
}

BassRhythm = {s4 s8 | c2 c2 | c2 s8 }
LyricBassRhythmI=  \lyricmode { c b | c }

staffBassRhythm =
\new Staff = staffbass \with { \remove "Clef_engraver" } {
  % This is not a RhythmicStaff  because it must be possible to append lyrics.

  \override Score.GridLine.extra-offset = #'( 13.0 . 0.0 ) % x.y
  \override Staff.StaffSymbol.line-positions = #'( 0 )
  % Shows one horizontal line. The vertical line
  %  (simulating a bar-line) is simulated by a grid
  % Search for 'grid' in this page to find all related functions
  \time 4/4
  {
    \context Voice = "VoiceBassRhythm"
    \stemDown \AltOn #0.6
    \relative c''
    {
      \BassRhythm
    }
    \AltOff
    \bar "|."
  }
}

\score {
  \new ChoirStaff <<
    \harmonies
    \staffVoice
    \context Lyrics = "lmelodyVoi"
      \with { alignBelowContext = astaffvoice }
      \lyricsto melodyVoi \verse
    \staffAccordionMel
    \staffTabLine
    \staffBassRhythm
    \context Lyrics = "lBassRhythmAboveI"
      \with { alignAboveContext = staffbass }
      \lyricsto VoiceBassRhythm \LyricBassRhythmI
  >>
}
</lilypond>

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[[Category:Instrument-specific]]
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