\version "2.18.2"
#(define-public (make-square-stencil stencil thickness padding)
  "Add a square box around @var{stencil}, producing a new stencil."
  (let* ((x-ext (ly:stencil-extent stencil X))
         (y-ext (ly:stencil-extent stencil Y))
         (x-length (interval-length x-ext))
         (y-length (interval-length y-ext))
         (new-x-ext (interval-widen x-ext  padding))
         (new-y-ext (interval-widen y-ext (+ (/ (- x-length y-length) 2) padding)))
         (y-rule (make-filled-box-stencil (cons 0 thickness) new-y-ext))
         (x-rule (make-filled-box-stencil
                   (interval-widen new-x-ext thickness) (cons 0 thickness))))
    (set! stencil (ly:stencil-combine-at-edge stencil X 1 y-rule padding))
    (set! stencil (ly:stencil-combine-at-edge stencil X -1 y-rule padding))
    (set! stencil (ly:stencil-combine-at-edge stencil Y 1 x-rule 0.0))
    (set! stencil (ly:stencil-combine-at-edge stencil Y -1 x-rule 0.0))
    ;; Uncomment to print x- and y-length
    ;; (newline)(write (interval-length (ly:stencil-extent stencil X)))
    ;; (newline)(write (interval-length (ly:stencil-extent stencil Y)))
    stencil))

#(define-markup-command (square layout props arg)
  (markup?)
  #:properties ((thickness 8)
                (font-size 0)
                (square-padding 0.2))
  "
@cindex enclosing text within a square box

Draw a square box round @var{arg}.  Looks at @code{thickness},
@code{square-padding} and @code{font-size} properties to determine line
thickness and padding around the markup.

@lilypond[verbatim,quote]
\\markup {
  \\override #'(square-padding . 0.5)
  \\square
  \\line { V. S. }
}
@end lilypond"
  (let* ((th (* (ly:output-def-lookup layout 'line-thickness)
                thickness))
         (pad (* (magstep font-size) square-padding))
         (m (interpret-markup layout props arg)))
    (make-square-stencil m th pad)))

music = \relative c'' {
   \set Staff.explicitClefVisibility = #all-invisible
  \override Staff.TimeSignature.transparent = ##t
  \override Staff.BarLine.transparent = ##t \stopStaff 
\once \override Score.RehearsalMark #'extra-offset = #'(4 . -3.5)
   \mark \markup \override #'(thickness . 7 )
   \fontsize #3.5 \circle { \pad-around #1 \bold "Fl" } 
}


 \score {
      \new Staff  <<       
        \new Voice = "s" <<
          \music
      >>
  >>   
\layout {line-width = 10} 
} 

music = \relative c'' {
   \set Staff.explicitClefVisibility = #all-invisible
  \override Staff.TimeSignature.transparent = ##t
  \override Staff.BarLine.transparent = ##t \stopStaff
  \once \override Score.RehearsalMark #'extra-offset = #'(4 . -3.5)
\mark \markup \square \bold \fontsize #1 "Mnd" 
}

\score {
      \new Staff  <<       
        \new Voice = "s" <<
          \music
        >>
      >>
\layout {line-width = 10}   
}

music = \relative c'' {
   \set Staff.explicitClefVisibility = #all-invisible
   \override Staff.TimeSignature.transparent = ##t
   \override Staff.BarLine.transparent = ##t \stopStaff
\once \override Score.RehearsalMark #'extra-offset = #'(4 . -3.5)
\mark \markup \override #'(thickness . 7 ) 
\fontsize #-7.5 \box \circle  {\pad-around #1.5 \bold  "Bde" }
} 
\score {
      \new Staff  <<       
        \new Voice = "s" <<
          \music
      >>
  >>
\layout {line-width = 10} 
}

#(define-markup-command (add-Y-centered layout props  arg1 arg2)
  (markup? markup?)

  (let ((m1 (interpret-markup layout props arg1))
        (m2 (interpret-markup layout props arg2)))
    (ly:stencil-add
      (ly:stencil-aligned-to m1 Y 0)
      (ly:stencil-aligned-to m2 Y 0))))
   
txt =
\markup \fill-line {
        \column {
  "Einsatz nacheinander (Anfang I/II), zunächst so weiter," 
  "dann auch gemeinsam," 
  "Unterbrechungen beim Weitergehen ad lib."
  "Solo: andere Stimme schwewigt (Zeichen geben)"
  "Artikulation, Oktavräume veränderbar (auch Repet./Improv.)"
  "Bei Ausführung oder Ergänzung durch andere Instrumente" 
  "jeweilige Anpassung und Einteilung"
  "und überhaupt: mit Heiterkeit und eigenen Gedanken..."              
  "                                                                                               EF"}
 }

image =
\markup \fill-line {
        ""
        ""
}

\markup {
        \add-Y-centered
        \txt
        \image
}


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