Re: relative offset of systems [WAS: Center-align a score]

[Thomas Morley]

Hi David,

nice stuff!

Some comments, though:

2017-04-27 19:27 GMT+02:00 David Nalesnik <address@hidden>:
> On Thu, Apr 27, 2017 at 12:22 PM, David Nalesnik
> <address@hidden> wrote:
>
>>
>> I'll just quote the relevant changes with some context.
>>
>> Within the function make-page-stencil:
>>
>> [...]
>>

I see no advantage to add 'extra-y' to the arguments.
Why not do the calculation in 'add-system' ...

>>  (add-to-page (lambda (stencil x y extra-y)
>
> Oh, "nota bene" the above line too!
>
>>                     (set! page-stencil
>>                           (ly:stencil-add page-stencil
>>                             (ly:stencil-translate stencil
>>                               (cons
>>                                (+
>>                                 system-xoffset x)
>>                                (-
>>                                 0 y extra-y (prop 'top-margin))) ; NB
>>
>>                               )))))
>>      (add-system
>>       (lambda (system)
>>         (let* ((stencil (paper-system-stencil system))
>>                (y (ly:prob-property system 'Y-offset 0))
>>                (extra-y (ly:prob-property system 'extra-Y-offset 0)) ; NB
>>                (is-title (paper-system-title?
>>                           system)))
>>           (add-to-page stencil
>>             (ly:prob-property system 'X-offset 0.0)
>>             y
>>             extra-y) ; NB


It will fail if system-separator-markup is used.

Here my attempt (for comparison I added greyed stencils)

     (add-system
      (lambda (system)
        (let* ((stencil (paper-system-stencil system))
               (y (ly:prob-property system 'Y-offset 0))
               (extra-y (ly:prob-property system 'extra-Y-offset 0)) ;; NB
               (is-title (paper-system-title?
                          system)))

;;;; For comparison: print the greyed system-stencil without extra-y
          (add-to-page (stencil-with-color stencil '(0.8 0.8 0.8))
            (ly:prob-property system 'X-offset 0.0)
            y)
;;;; The moved system-stencil
          (add-to-page stencil
            (ly:prob-property system 'X-offset 0.0)
            (+ y extra-y)) ;; NB

            (if (and (ly:stencil? system-separator-stencil)
                     last-system
                     (not (paper-system-title? system))
                     (not (paper-system-title? last-system)))
                (begin
;;;; For comparison: print the greyed system-separator-stencil without 'extra-y
                  (add-to-page
                   (stencil-with-color system-separator-stencil '(0.8 0.8 0.8))
                   0

                   (average (- last-y
                               (car (paper-system-staff-extents last-system)))
                            (- y
                               (cdr (paper-system-staff-extents system)))))

;;;; The moved system-separator-stencil
                  (add-to-page
                   system-separator-stencil
                   0

                   (+
                     (average (- last-y
                                 (car (paper-system-staff-extents last-system)))
                              (- y
                                 (cdr (paper-system-staff-extents system))))
                     (/ extra-y 2)))))  ;; NB
            (set! last-system system)
;;;; set last-y, taking extra-y into account
            (set! last-y (+ y extra-y)))))  ;; NB

As an example I used:

\paper {
  system-separator-markup = \slashSeparator
  ragged-last-bottom = ##t
}
top = \repeat unfold 5 { c''4 d'' e'' f'' }

bottom = {
  \clef bass
  \repeat unfold 5 { c,1 }
  \break
}

\new PianoStaff <<
  \new Staff {
    \top
    \top
    \top
  }
  \new Staff {
    \bottom
    \overrideProperty
    Score.NonMusicalPaperColumn.line-break-system-details
    #'((extra-Y-offset . 2))
    \bottom
    \overrideProperty
    Score.NonMusicalPaperColumn.line-break-system-details
    #'((extra-Y-offset . 5))
    \bottom
  }
>>

png attached



Thanks,
  Harm

atest-56.png
Description: PNG image