Re:

[Philippe ZELLER]

Dear Aaron,

I found a solution. : trick the "hideEveryOtherBarLine" mechanism so it believes the bar number where the extra "|." bar is located is odd.

%%%%%%%%

a2. | 

b2 \fermata  _"Fine"  \set Score.currentBarNumber = #55  \bar "|."  r4 

\set Score.currentBarNumber = #55  |

a2 b4 |

%%%%%%

Without the double change of bar numbers the "|." bar is made transparent by \hideEveryOtherBarLine . 

Thanks a lot again :-)

Philippe

Le dim. 28 mars 2021 à 01:54, Philippe ZELLER <peliphi@gmail.com> a écrit :

Dear Aaron, 

this is brilliant ! I'm impressed as I would never have been able to write code like this myself.

Plus : your solution is compatible with multiMeasureRests.

Yet another challenge for you though :-) :

In the middle of the piece there is a \bar "|." occurring after the second beat, and when using your custom engraver this barline becomes invisible.

How can I make it visible again ?

Best regards,

Philippe 

Le sam. 27 mars 2021 à 21:52, Aaron Hill <lilypond@hillvisions.com> a écrit :

On 2021-03-27 1:04 pm, Philippe ZELLER wrote:
> Dear lilypond fellow users,
> it sometimes occurs in barock music that only every other barline is
> visible, (see e.g. Haendel's Salomo, choir at the end of Act II ) or
> that
> every other barline is printed in reduced size.(see e.g. Bach Mass in
> H-moll, nr 27 "dona nobis pacem" ).
> Is there a way to get this result in lilypond ?
>
> I first tried
> \set Score.barLineVisibility = #(every-nth-bar-number-visible 2)
> that I made up after an equivalent syntax for barNumber, but to no
> avail.
> Maybe I didn't put it in the right context ?
>
> Finally I used a rather complicated procedure based on
> global = {
>       \repeat unfold 24 { s2. \once \override Staff.BarLine.transparent
> =
> ##t  s2. \once \override Staff.BarLine.transparent = ##f }
>         }
> which works but is not fully compatible, for example it does not work
> with
> multiMeasureRests.
>
> Many thanks in advance for your suggestions !

An engraver should be able to do the work:

%%%%
\version "2.22.0"

hideEveryOtherBarLine =
#(lambda (ctx)
   (define (bar-num)
    (ly:context-property ctx 'currentBarNumber))
   (make-engraver
    (acknowledgers
     ((bar-line-interface trans grob source)
      (if (= 0 (modulo (bar-num) 2))
       (ly:grob-set-property! grob 'transparent #t))))))

\new Staff
\with { \consists \hideEveryOtherBarLine }
\repeat unfold 10 { b'1 }
%%%%


-- Aaron Hill