+
+;; The glissando routine works similarly to the slur routine; if the
+;; fret number is "tied to", it should become parenthesized.
+(define-public (glissando::draw-tab-glissando grob)
+ (let* ((original (ly:grob-original grob))
+ (left-tab-note-head (ly:spanner-bound original LEFT))
+ (cautionary (ly:grob-property left-tab-note-head 'display-cautionary #f)))
+
+ (and cautionary
+ ;; increase left padding to avoid collision between
+ ;; closing parenthesis and glissando line
+ (ly:grob-set-nested-property! grob '(bound-details left padding) 0.5))
+ (ly:line-spanner::print grob)))
+
+;; for \tabFullNotation, the stem tremolo beams are too big in comparison to
+;; normal staves; this wrapper function scales accordingly:
+(define-public (stem-tremolo::calc-tab-width grob)
+ (let ((width (ly:stem-tremolo::calc-width grob))
+ (staff-space (ly:staff-symbol-staff-space grob)))
+ (/ width staff-space)))
+
+
+;; a callback for custom fret labels
+(define ((tab-note-head::print-custom-fret-label fret) grob)
+ (ly:grob-set-property! grob 'text (make-vcenter-markup fret))
+ (tab-note-head::print grob))
+(export tab-note-head::print-custom-fret-label)
+
+(define-public (tab-note-head::print grob)
+ (define (is-harmonic? grob)
+ (let ((arts (ly:event-property (event-cause grob) 'articulations)))
+ (or (pair? (filter (lambda (a)
+ (ly:in-event-class? a 'harmonic-event))
+ arts))
+ (eq? (ly:grob-property grob 'style) 'harmonic))))
+
+ (let* ((cautionary (ly:grob-property grob 'display-cautionary #f))
+ (details (ly:grob-property grob 'details '()))
+ (harmonic-props (assoc-get 'harmonic-properties details '()))
+ (harmonic-angularity (assoc-get 'angularity harmonic-props 2))
+ (harmonic-half-thick (assoc-get 'half-thickness harmonic-props 0.075))
+ (harmonic-padding (assoc-get 'padding harmonic-props 0))
+ (harmonic-proc (assoc-get 'procedure harmonic-props parenthesize-stencil))
+ (harmonic-width (assoc-get 'width harmonic-props 0.25))
+ (cautionary-props (assoc-get 'cautionary-properties details '()))
+ (cautionary-angularity (assoc-get 'angularity cautionary-props 2))
+ (cautionary-half-thick (assoc-get 'half-thickness cautionary-props 0.075))
+ (cautionary-padding (assoc-get 'padding cautionary-props 0))
+ (cautionary-proc (assoc-get 'procedure cautionary-props parenthesize-stencil))
+ (cautionary-width (assoc-get 'width cautionary-props 0.25))
+ (output-grob (ly:text-interface::print grob))
+ (ref-grob (grob-interpret-markup grob "8"))
+ (offset-factor (assoc-get 'head-offset details 3/5))
+ (column-offset (* offset-factor
+ (interval-length
+ (ly:stencil-extent ref-grob X)))))
+
+ (if (is-harmonic? grob)
+ (set! output-grob (harmonic-proc output-grob
+ harmonic-half-thick
+ harmonic-width
+ harmonic-angularity
+ harmonic-padding)))
+ (if cautionary
+ (set! output-grob (cautionary-proc output-grob
+ cautionary-half-thick
+ cautionary-width
+ cautionary-angularity
+ cautionary-padding)))
+ (ly:stencil-translate-axis
+ (ly:stencil-aligned-to output-grob X CENTER)
+ column-offset
+ X)))
+
+;; Harmonic definitions
+
+(define node-positions
+ ;; for the node on m/n-th of the string length, we get the corresponding
+ ;; (exact) fret position by calculating p=(-12/log 2)*log(1-(m/n));
+ ;; since guitarists normally use the forth fret and not the 3.8th, here
+ ;; are rounded values, ordered by
+ ;; 1/2
+ ;; 1/3 2/3
+ ;; 1/4 2/4 3/4 etc.
+ ;; The value for 2/4 is irrelevant in practical, bacause the string sounds
+ ;; only one octave higher, not two, but since scheme normalizes the fractions
+ ;; anyway, these values are simply placeholders for easier indexing.
+ ;; According to the arithmetic sum, the position of m/n is at 1/2*(n-2)(n-1)+(m-1)
+ ;; if we start counting from zero
+ (vector 12
+ 7 19
+ 5 12 24
+ 4 9 16 28
+ 3 7 12 19 31
+ 2.7 5.8 9.7 14.7 21.7 33.7
+ 2.3 5 8 12 17 24 36
+ 2 4.4 7 10 14 19 26 38 ))
+
+(define partial-pitch
+ (vector '(0 0 0)
+ '(1 0 0)
+ '(1 4 0)
+ '(2 0 0)
+ '(2 2 0)
+ '(2 4 0)
+ '(2 6 -1/2)
+ '(3 0 0)
+ '(3 1 0)))
+
+(define fret-partials
+ '(("0" . 0)
+ ("12" . 1)
+ ("7" . 2)
+ ("19" . 2)
+ ("5" . 3)
+ ("24" . 3)
+ ("4" . 4)
+ ("9" . 4)
+ ("16" . 4)
+ ("3" . 5)
+ ("2.7" . 6)
+ ("2.3" . 7)
+ ("2" . 8)))
+
+(define-public (ratio->fret ratio)
+ "Calculate a fret number given @var{ratio} for the harmonic."
+ (let* ((nom (numerator ratio))
+ (den (denominator ratio))
+ (index (+ (* (- den 2)
+ (- den 1)
+ 1/2)
+ nom -1)))
+ (number->string (vector-ref node-positions index))))
+
+(define-public (ratio->pitch ratio)
+ "Calculate a pitch given @var{ratio} for the harmonic."
+ (let* ((partial (1- (denominator ratio)))
+ (pitch (vector-ref partial-pitch partial)))
+
+ (ly:make-pitch (first pitch)
+ (second pitch)
+ (third pitch))))
+
+(define-public (fret->pitch fret)
+ "Calculate a pitch given @var{fret} for the harmonic."
+ (let* ((partial (assoc-get fret fret-partials 0))
+ (pitch (vector-ref partial-pitch partial)))
+
+ (ly:make-pitch (first pitch)
+ (second pitch)
+ (third pitch))))
+
+(define-public (calc-harmonic-pitch pitch music)
+ "Calculate the harmonic pitches in @var{music} given
+@var{pitch} as the non-harmonic pitch."
+ (let ((es (ly:music-property music 'elements))
+ (e (ly:music-property music 'element))
+ (p (ly:music-property music 'pitch)))
+ (cond
+ ((pair? es)
+ (ly:music-set-property! music 'elements
+ (map (lambda (x) (calc-harmonic-pitch pitch x)) es)))
+ ((ly:music? e)
+ (ly:music-set-property! music 'element (calc-harmonic-pitch pitch e)))
+ ((ly:pitch? p)
+ (begin
+ (set! p (ly:pitch-transpose p pitch))
+ (ly:music-set-property! music 'pitch p))))
+ music))
+
+(define-public (make-harmonic mus)
+ "Convert music variable @var{mus} to harmonics."
+ (let ((elts (ly:music-property mus 'elements))
+ (elt (ly:music-property mus 'element)))
+ (cond
+ ((pair? elts)
+ (for-each make-harmonic elts))
+ ((ly:music? elt)
+ (make-harmonic elt))
+ ((music-is-of-type? mus 'note-event)
+ (set! (ly:music-property mus 'articulations)
+ (append
+ (ly:music-property mus 'articulations)
+ (list (make-music 'HarmonicEvent))))))
+ mus))