Choises

[Yoann LE BARS]

Hello everybody out there!

        I must write a score for several instruments. In this score, interprets
must several times choose between two alternatives. To symbolize these
choices, the staff is split in two, every staff being linked to the
other with an opening angle bracket (“<”). At the beginning of a new
line, staffs are also linked with an angle opening bracket. The end of
alternative is symbolized with a closing angle bracket (“>”). I have
created a hand-made example (without notes) you can see here:

https://cloud.le-bars.net/index.php/s/zIIqGlcSa3XCdi4

        I am quite certain it can be done with Lilypond, but I do not have a
clue how to do it. Therefore, I have prepared some code available here:

http://lilybin.com/tjc9ai/3

        I have also copied this code at the end of this message.

        There are two instruments in this example, a flute and a clarinet
(clarinet is written in French, i.e. “clarinette”, in variable names).
For this two instruments, there is four section A, B, C and D. In
section B and C, they have two choices: Ba and Bb as well as Ca and Cb.
Therefore, fluteBa must be superposed over fluteBb, as well as fluteCa
over fluteCb, clarinetteBa over clarinetteBb and clarinetteCa over
clarinetteCb in the way presented in my hand-made example.

        Well, I hope this is understandable. Does anyone have an idea how to do
this?

        Best regards.

\version "2.18.2"

#(define (chiffr-triche grob)
   (grob-interpret-markup grob
      (markup #:override '(baseline-skip . 0)
        (#:line ((#:center-column (#:number "9" #:number "8")))))))

\paper {
  indent = 3\cm
  short-indent = 1.5\cm
}

\layout {
  \context {
    \Score
    \remove "Timing_translator"
    \remove "Default_bar_line_engraver"
  }
  \context {
    \Staff \RemoveEmptyStaves
    \consists "Timing_translator"
    \consists "Default_bar_line_engraver"
  }
}

fluteA = {
  \time 4/4
  \relative c' {
    \repeat unfold 12 {c8 d e f}
  }
}

fluteBa = {
  \bar "||"
  \once \override Staff.TimeSignature.stencil = #chiffr-triche
  \time 3/4
  \relative c' {
    \repeat unfold 12 {c8*2/3[d e]}
  }
}

fluteBb = {
  \bar "||"
  \once \override Staff.TimeSignature.stencil = #chiffr-triche
  \time 3/4
  \relative c' {
    \repeat unfold 12 {e8*2/3[d c]}
  }
}

fluteCa = {
  \bar "||"
  \time 4/4
  \relative c' {
    \repeat unfold 12 {c8 d e f}
  }
}

fluteCb = {
  \bar "||"
  \time 4/4
  \relative c' {
    %f8 e d c \bar "" \break
    \repeat unfold 12 {f8 e d c}
  }
}

fluteD = {
  \relative c' {
    c8 d e f e d c4~ c1 \bar "|."
  }
}

clarinetteA = {
  \time 4/4
  \relative c' {
    \repeat unfold 16 {e8 f g a}
  }
}

clarinetteBa = {
  \bar "||"
  \once \override Staff.TimeSignature.stencil = #chiffr-triche
  \time 3/4
  \relative c' {
    e8*2/3[f g] \bar "" \break
    \repeat unfold 11 {e[f g]}
  }
}

clarinetteBb = {
  \bar "||"
  \once \override Staff.TimeSignature.stencil = #chiffr-triche
  \time 3/4
  \relative c' {
    g'8*2/3[f e] \bar "" \break
    \repeat unfold 11 {g[f e]}
  }
}

clarinetteCa = {
  \bar "||"
  \time 4/4
  \relative c' {
    \repeat unfold 8 {a'8 g f e}
  }
}

clarinetteCb = {
  \bar "||"
  \time 4/4
  \relative c' {
    \repeat unfold 8 {e8 f g a}
  }
}

clarinetteD = {
  \relative c' {
    f8 g a b a g f4~ f1 \bar "|."
  }
}

\score {
  <<
    \accidentalStyle Score.modern-cautionary
    \new Staff \with {
        instrumentName = #"Flûte"
        shortInstrumentName = #"Fl."
      }
      {
        \fluteA
        \fluteBa
        \fluteCa
        \fluteD
      }

    \new Staff \with {
      instrumentName = \markup {\concat {"Clarinette en Si" \flat}}
      shortInstrumentName = \markup {\concat {"Clar. Si" \flat}}
    }
    {
      \clarinetteA
      \clarinetteBa
      \clarinetteCa
      \clarinetteD
    }
  >>
}

-- 
Yoann LE BARS
http://le-bars.net/yoann/
Diaspora* : yleb...@framasphere.org