Re: Cross-staff Glissando Stencil Error

[David Nalesnik]

On Mon, Nov 18, 2013 at 10:08 AM, Piaras Hoban <address@hidden> wrote:

David Nalesnik-2 wrote

> This seems like a bug to me.
>
> I applied your override to a similar grob, VoiceFollower, to see if the
> problem is just with Glissando.  I get the same disruption of vertical
> spacing.

David, thanks for your input. I fear it is a bug but not limited to stencil
(must be something lower level that stencil is calling?).

I think it has to do with when 'after-line-breaking is called.  Vertical spacing obviously hasn't been solidified.  If I modify your override/function to work on 'color, which is processed very late, I get the stencil without disruption and can get information from it.

 \version "2.17.95"

#(define (stencil-test grob)

  (let* ((stencil (ly:grob-property grob 'stencil)))

    (display (ly:stencil-extent stencil Y))

    'red))

\score {

  \new PianoStaff <<

    \new Staff = "right" {

      \once \override Glissando.color = #stencil-test

      c''2. \glissando

      \change Staff = "left" c,4 |

    }

  \new Staff = "left" {\clef bass s1}

  >>

}