Re: Whiteout box function by Thomas Morley / need help

[Thomas Morley]

2014-04-21 16:40 GMT+02:00 Karol Majewski <address@hidden>:
> Harm,
>
> this change is related to issue 621:
> http://code.google.com/p/lilypond/issues/detail?id=621
>
> Now, I do not accept this solution. It is simply against the rules. 
> DynamicText shouldn't have influence on spacaing. Therefore I prefer whiteout.
>
> So I use:
>
> \context {
>   \Staff
>   \override DynamicText.extra-spacing-width = #'(+inf.0 . -inf.0)
> }
>
> Note that your previous function (the one that contains 
> flexible-stencil-whiteout) works well with DynamiText. But the drawback is 
> that it doesn't allow to set left and right X-extent.
>
> -- Karol

Hi Karol,

below the newest version.
DynamicText is special-cased and it always returns a visual output for
DynamicText like
'self-alignment -X = CENTER

Please test:

\version "2.19.4"

moreWhiteout =
#(define-music-function (parser location grob-name adds)(string? pair?)
"
 Increases the grob-stencil for 'whiteout, setting the 'layer to 10.
 DynamicText is special-cased:
   It's 'self-alignment-X is calculated to ensure same visual output as if
   'self-alignment-X = CENTER
   TODO: Make it work for other values of 'self-alignment-X
"

  (define more-stencil-whiteout
    (lambda (grob)
      (let* ((function (assoc-get 'stencil
                            (reverse (ly:grob-basic-properties grob))))
             (stil ;; Ugh, is there no better way to test that a grob has no
                   ;; 'stencil and that no other previous procedure assigned
                   ;; a stencil-value to said grob?
                   (if (and (procedure? function)
                            (not (eq? (procedure-name function)
                                      'more-stencil-whiteout)))
                       (function grob)
                       (begin
                         (ly:warning "~a has no stencil. Ignoring" grob)
                         #f))))
        (if stil
            (let*((x-ext (ly:stencil-extent stil X))
                  (y-ext (ly:stencil-extent stil Y))
                  (add-to-x-ext (if (pair? (car adds)) (car adds) adds))
                  (add-to-y-ext (if (pair? (cdr adds)) (cadr adds) '(0 . 0)))
                  ;(self-alignment-X (ly:grob-property grob 'self-alignment-X))
                  (new-stil
                    (ly:make-stencil
                       (ly:stencil-expr stil)
                       (offset-add x-ext add-to-x-ext)
                       (offset-add y-ext add-to-y-ext))))
              ;(display self-alignment-X)
              (if (grob::has-interface grob 'dynamic-text-interface)
                  ;(and (not (null? self-alignment-X)) (= 0 self-alignment-X))
                  (let* ((new-stencil-length
                           (interval-length (ly:stencil-extent new-stil X)))
                         (orig-stencil-length
                           (interval-length (ly:stencil-extent stil X))))
                    (ly:grob-set-property! grob 'self-alignment-X
                      (if (not (= 0 (- new-stencil-length orig-stencil-length)))
                          (/ (- (- new-stencil-length (cdr add-to-x-ext))
                                (+ orig-stencil-length (cdr add-to-x-ext)))
                             new-stencil-length)
                          0))))
              new-stil)
            #f))))
  #{
    \once \override $grob-name . layer = #10
    \once \override $grob-name . whiteout = ##t
    \once \override $grob-name . stencil = #more-stencil-whiteout
  #})

%%%%%%%%%%%%%%%%%%%%%%%
%% EXAMPLE
%%%%%%%%%%%%%%%%%%%%%%%

\layout {
  \override DynamicText.extra-spacing-width = #'(+inf.0 . -inf.0)
}

musicI = { \time 2/4 \repeat unfold 16 b8 }

musicII = {
  r2
  %% apply to X- and Y-axis
  \moreWhiteout TextScript #'((-2 . 0.5)(0 . 2))
  b4^"XXXXXX"
  b
  r
  \moreWhiteout DynamicText #'((-3.2 . 4.12)(0 . 0))
  r^\pppp
  %% apply to X-axis only
  \moreWhiteout TextScript #'(-2 . 10.5)
  b4^"XXXXXX" b
}

\new StaffGroup <<
  \new Staff \relative c'' \musicI
  \new Staff \relative c'' \musicII
>>


Cheers,
  Harm