Re: temporarily disable Dot_column_engraver?

[Thomas Morley]

2018-04-18 13:22 GMT+02:00 foxfanfare <address@hidden>:
> This post is old, but I can't find the solution for this specific problem.
> In a general way, I wonder how it is possible to remove an engraver
> temporarily?
>
> For this dot_column case, here's the exemple wrote in Elaine Gould's book:
>
> \version "2.19.80"
>
> \score {
>   \relative c' {
>     \cadenzaOn
>     \omit Staff.TimeSignature
>    << { c'2.^"OK" b \bar "|" b4. a } \\
>        { b2. a c4. b } >> \bar "|"
>     << { c2. \bar "|" b } \\
>        { b2 a4 a2 g4 } >> \bar "|"
>
>     << { *2.^"Not OK" <c d f>1. } \\
>        { <c, d f>2. <e g>4. r <e g>2. } >> \bar "|"
>   }
> }
>
> \score {
>   \relative c' {
>     \cadenzaOn
>     \omit Staff.TimeSignature
>    << { c'2. b^"Not OK" \bar "|" b4. a } \\
>        { b2. a c4. b } >> \bar "|"
>     << { c2. \bar "|" b } \\
>        { b2 a4 a2 g4 } >> \bar "|"
>
>     << { *2.^"OK" <c d f>1. } \\
>        { <c, d f>2. <e g>4. r <e g>2. } >> \bar "|"
>   }
>   \layout {
>     \context {
>       \Staff
>       \remove Dot_column_engraver
>     }
>     \context {
>       \Voice
>       \consists Dot_column_engraver
>     }
>   }
> }
>
> How is it possible to combine those two solutions in a same staff?
> Dot_column.PNG
> <http://lilypond.1069038.n5.nabble.com/file/t5604/Dot_column.PNG>



It's not possible to consist/remove engraver temporarily, but you can
have several named Voices (keep them alive) with and without the
engraver:


\score {
    \new Staff \with { \omit TimeSignature }
    <<
      \new Voice = "x" \with { \consists Dot_column_engraver } s4*24
      \new Voice = "y" \with { \consists Dot_column_engraver } s4*24
      \new Voice ="z"
        \relative c' {
            \cadenzaOn
            \voiceOne
            c'2. b
            \bar "|"
            b4. a c2.
            \bar "|"
            b
            \bar "|"
            \context Voice = "x" {
              \voiceOne
              < b c d >2. <c d f>1.
            }
            c2. b
            \bar "|."
        }
      \new Voice = "xy"
        \relative c' {
            \voiceTwo
            b'2. a
            c4. b b2
            \context Voice = "y" {
              \voiceTwo
              a4 a2 g4 < c, d f >2. <e g>4. r <e g>2.
            }
            b'2. a
        }
    >>
}


Cheers,
  Harm