\version "2.12.0"

%Centers
markL = \once \override Score.RehearsalMark #'self-alignment-X = #-1
emptyMark = \once \override Score.RehearsalMark #'X-extent = #'(0 . 0)
#(set-default-paper-size "letter")

%bowings
dwn = \downbow
up = \upbow

%breath mark as pause
pause = {\once \override BreathingSign #'extra-offset = #'(0.0 . 1.0)\breathe}

%invisible notes for hanging ties
inv = { \override Voice.NoteHead  #'transparent = ##t
			\override Voice.Stem  #'transparent = ##t }
unv = { \revert Voice.NoteHead  #'transparent
			\revert Voice.Stem  #'transparent }
			
%tremolo

% parentheses
#(define (parenthesize-callback callback)
   (define (parenthesize-stencil grob)
     (let* ((fn (ly:grob-default-font grob))
	    (pclose (ly:font-get-glyph fn "accidentals.rightparen"))
	    (popen (ly:font-get-glyph fn "accidentals.leftparen"))
	    (subject (callback grob))

		; get position of stem
		(stem-pos (ly:grob-property grob 'stem-attachment))
		
	    ; remember old size
	    (subject-dim-x (ly:stencil-extent subject 0))
	    (subject-dim-y (ly:stencil-extent subject 1)))

        ;; add parens
        (set! subject
	     (ly:stencil-combine-at-edge 
	      (ly:stencil-combine-at-edge subject 0 1 pclose 0)
	      0 -1 popen  0))
		  
		; adjust stem position
		(ly:grob-set-property! grob 'stem-attachment
			(cons (- (car stem-pos) 0.43) (cdr stem-pos)))

	; adjust size
       (ly:make-stencil
        (ly:stencil-expr subject)
		  (cons (- (car subject-dim-x) 0.5) (+ (cdr subject-dim-x) 0.5))
		  subject-dim-y)))
   parenthesize-stencil)