Modify fret calculation algorithm

Zero fingering creates an open string fret.

Add defaultStrings property to define strings that will be used
 in calculating frets if no string number is specified in a chord.

A bad request for an open string pitch will set a warning and set
 the pitch if possible on a non-open string.

Add regression tests for these cases.

diff --git a/input/regression/tablature-default-strings.ly b/input/regression/tablature-default-strings.ly
new file mode 100644 (file)
index 0000000..fb2065b
--- /dev/null
+++ b/input/regression/tablature-default-strings.ly
@@ -0,0 +1,31 @@
+\version "2.13.41"
+
+\header {
+  texidoc = "
+Context property @code{defaultStrings} defines desired strings
+for fret calculations if no strings are defined explicitly.
+"
+}
+
+mymusic = \relative c {
+  <c c'>4
+  \set defaultStrings = #'(5 3)
+  <c c'>4
+  <d d'>4
+  <e e'>4
+  <c c'>2\6\4
+  \unset defaultStrings
+  <c c'>2
+}
+
+\score {
+  <<
+    \new Staff {
+      \clef "treble_8"
+      \mymusic
+    }
+    \new TabStaff {
+      \mymusic
+    }
+  >>
+}

diff --git a/input/regression/tablature-zero-finger.ly b/input/regression/tablature-zero-finger.ly
new file mode 100644 (file)
index 0000000..7c2dd4b
--- /dev/null
+++ b/input/regression/tablature-zero-finger.ly
@@ -0,0 +1,27 @@
+\version "2.13.41"
+
+\header {
+  texidoc="
+A fingering indication of zero counts as an open string for fret
+calculations.  An inappropriate request for an open string will generate
+a warning message and set the requested pitch in the tablature.
+"
+}
+
+mymusic = \relative c {
+  \set minimumFret = #1
+  <d-0 d'-2 f-3 a-1>1
+  <f-0>
+}
+
+\score {
+  <<
+    \new Staff {
+      \clef "treble_8"
+      \mymusic
+    }
+    \new TabStaff {
+      \mymusic
+    }
+  >>
+}

diff --git a/lily/fretboard-engraver.cc b/lily/fretboard-engraver.cc
index 4cbd08578c8db8cd5fd94af599ee7a118ba78198..c0614d7b8bec765f44cf35af05a943b9e1ff3b7d 100644 (file)
--- a/lily/fretboard-engraver.cc
+++ b/lily/fretboard-engraver.cc
@@ -40,6 +40,7 @@ class Fretboard_engraver : public Engraver
 
   vector<Stream_event *> note_events_;
   vector<Stream_event *> tabstring_events_;
+  vector<Stream_event *> fingering_events_;
 public:
   TRANSLATOR_DECLARATIONS (Fretboard_engraver);
 
@@ -49,6 +50,7 @@ protected:
   virtual void derived_mark () const;
   DECLARE_TRANSLATOR_LISTENER (note);
   DECLARE_TRANSLATOR_LISTENER (string_number);
+  DECLARE_TRANSLATOR_LISTENER (fingering);
 
 private:
   SCM last_fret_notes_;
@@ -80,6 +82,13 @@ Fretboard_engraver::listen_string_number (Stream_event *ev)
   tabstring_events_.push_back (ev);
 }
 
+IMPLEMENT_TRANSLATOR_LISTENER (Fretboard_engraver, fingering);
+void
+Fretboard_engraver::listen_fingering (Stream_event *ev)
+{
+  fingering_events_.push_back (ev);
+}
+
 void
 Fretboard_engraver::process_music ()
 {
@@ -89,6 +98,9 @@ Fretboard_engraver::process_music ()
   SCM tab_strings = articulation_list (note_events_,
                                       tabstring_events_,
                                       "string-number-event");
+  SCM fingers = articulation_list (note_events_,
+                                  fingering_events_,
+                                  "fingering-event");
   fret_board_ = make_item ("FretBoard", note_events_[0]->self_scm ());
   SCM fret_notes = ly_cxx_vector_to_list (note_events_);
   SCM proc = get_property ("noteToFretFunction");
@@ -96,7 +108,7 @@ Fretboard_engraver::process_music ()
     scm_call_4 (proc,
                context ()->self_scm (),
                fret_notes,
-               tab_strings,
+               scm_list_2 (tab_strings, fingers),
                fret_board_->self_scm ());
   SCM changes = get_property ("chordChanges");
   if (to_boolean (changes) && scm_is_pair (last_fret_notes_)
@@ -112,6 +124,7 @@ Fretboard_engraver::stop_translation_timestep ()
   fret_board_ = 0;
   note_events_.clear ();
   tabstring_events_.clear ();
+  fingering_events_.clear ();
 }
 
 ADD_TRANSLATOR (Fretboard_engraver,
@@ -124,6 +137,7 @@ ADD_TRANSLATOR (Fretboard_engraver,
 
                /* read */
                "chordChanges "
+               "defaultStrings "
                "highStringOne "
                "maximumFretStretch "
                "minimumFret "
@@ -134,5 +148,5 @@ ADD_TRANSLATOR (Fretboard_engraver,
 
                /* write */
                ""
-               );
+                );
 

diff --git a/lily/tab-note-heads-engraver.cc b/lily/tab-note-heads-engraver.cc
index dbd6fa85175ea2d23efaf9a638226cb982053afb..8e81ba324e3f04b9b02e13c89b196e156a61ee22 100644 (file)
--- a/lily/tab-note-heads-engraver.cc
+++ b/lily/tab-note-heads-engraver.cc
@@ -43,6 +43,7 @@ class Tab_note_heads_engraver : public Engraver
 {
   vector<Stream_event *> note_events_;
   vector<Stream_event *> tabstring_events_;
+  vector<Stream_event *> fingering_events_;
 
 public:
   TRANSLATOR_DECLARATIONS (Tab_note_heads_engraver);
@@ -50,6 +51,7 @@ public:
 protected:
   DECLARE_TRANSLATOR_LISTENER (note);
   DECLARE_TRANSLATOR_LISTENER (string_number);
+  DECLARE_TRANSLATOR_LISTENER (fingering);
   void process_music ();
 
   void stop_translation_timestep ();
@@ -73,12 +75,22 @@ Tab_note_heads_engraver::listen_string_number (Stream_event *ev)
   tabstring_events_.push_back (ev);
 }
 
+IMPLEMENT_TRANSLATOR_LISTENER (Tab_note_heads_engraver, fingering);
+void
+Tab_note_heads_engraver::listen_fingering (Stream_event *ev)
+{
+  fingering_events_.push_back (ev);
+}
+
 void
 Tab_note_heads_engraver::process_music ()
 {
   SCM tab_strings = articulation_list (note_events_,
                                       tabstring_events_,
                                       "string-number-event");
+  SCM defined_fingers = articulation_list (note_events_,
+                                          fingering_events_,
+                                          "fingering-event");
   SCM tab_notes = ly_cxx_vector_to_list (note_events_);
   SCM proc = get_property ("noteToFretFunction");
   SCM string_fret_finger = SCM_EOL;
@@ -86,7 +98,8 @@ Tab_note_heads_engraver::process_music ()
     string_fret_finger = scm_call_3 (proc,
                                     context ()->self_scm (),
                                     tab_notes,
-                                    tab_strings);
+                                    scm_list_2 (tab_strings,
+                                                defined_fingers));
   SCM note_entry = SCM_EOL;
   SCM string_number = SCM_EOL;
   SCM fret = SCM_EOL;
@@ -123,6 +136,7 @@ Tab_note_heads_engraver::stop_translation_timestep ()
 {
   note_events_.clear ();
   tabstring_events_.clear ();
+  fingering_events_.clear ();
 }
 
 ADD_TRANSLATOR (Tab_note_heads_engraver,
@@ -134,6 +148,7 @@ ADD_TRANSLATOR (Tab_note_heads_engraver,
                "TabNoteHead ",
 
                /* read */
+               "defaultStrings "
                "fretLabels "
                "highStringOne "
                "middleCPosition "
@@ -144,6 +159,7 @@ ADD_TRANSLATOR (Tab_note_heads_engraver,
                "tablatureFormat "
                "tabStaffLineLayoutFunction ",
 
-               /* write */ ""
+               /* write */
+               ""
                 );
 

diff --git a/scm/define-context-properties.scm b/scm/define-context-properties.scm
index f758c04ca1a09085f57323163b6d3029a3d963f3..d4cfe137662e5aa457ce61afbcb6aab178b09ff5 100644 (file)
--- a/scm/define-context-properties.scm
+++ b/scm/define-context-properties.scm
@@ -188,6 +188,9 @@ non-hairpin decrescendo, i.e., @samp{dim.}.")
 
 This variable is read by @rinternals{Timing_translator} at
 @rinternals{Score} level.")
+     (defaultStrings ,list? "A list of strings to use in calculating
+frets for tablatures and fretboards if no strings are provided in
+the notes for the current moment.")
      (doubleRepeatType ,string? "Set the default bar line for double
 repeats.")
      (doubleSlurs ,boolean? "If set, two slurs are created for every

diff --git a/scm/translation-functions.scm b/scm/translation-functions.scm
index 67653bc49a8da4709cd2ad5219c77b43eeca9b4c..4214d05665070c34d0faa9ead3c5c2a098819779 100644 (file)
--- a/scm/translation-functions.scm
+++ b/scm/translation-functions.scm
@@ -207,9 +207,15 @@
     (set! (ly:grob-property grob 'dot-placement-list) placement-list)))
 
 (define-public
-  (determine-frets context notes defined-strings . rest)
+  (determine-frets context notes specified-info . rest)
   "Determine string numbers and frets for playing @var{notes}
-as a chord, given specified string numbers @var{defined-strings}.
+as a chord, given specified information  @var{specified-info}.
+@var{specified-info} is a list with two list elements,
+specified strings @var{defined-strings} and
+specified fingerings @var{defined-fingers}.  Only a fingering of
+0 will affect the fret selection, as it specifies an open string.
+If @var{defined-strings} is @code{'()}, the context property
+@code{defaultStrings} will be used as a list of defined strings.
 Will look for predefined fretboards if @code{predefinedFretboardTable}
 is not @code {#f}.  If @var{rest} is present, it contains the
 FretBoard grob, and a fretboard will be
@@ -248,6 +254,9 @@ dot placement entries."
                                  (eq? (car l) 'open)))
                  placement-list)))
 
+  (define (entry-count art-list)
+    (length (filter (lambda (x) (not (null? x)))
+                    art-list)))
 
   (define (get-predefined-fretboard predefined-fret-table tuning pitches)
     "Search through @var{predefined-fret-table} looking for a predefined
@@ -282,6 +291,21 @@ chords.  Returns a placement-list."
          (string-count (length tunings))
          (grob (if (null? rest) '() (car rest)))
         (pitches (map (lambda (x) (ly:event-property x 'pitch)) notes))
+         (defined-strings (map (lambda (x)
+                                 (if (null? x)
+                                     x
+                                     (ly:event-property x 'string-number)))
+                               (car specified-info)))
+         (defined-fingers (map (lambda (x)
+                                 (if (null? x)
+                                     x
+                                     (ly:event-property x 'digit)))
+                               (cadr specified-info)))
+         (default-strings (ly:context-property context 'defaultStrings '()))
+         (strings-used (if (and (zero? (entry-count defined-strings))
+                                (not (zero? (entry-count default-strings))))
+                           default-strings
+                           defined-strings))
          (predefined-fretboard
           (if predefined-fret-table
               (get-predefined-fretboard
@@ -289,12 +313,12 @@ chords.  Returns a placement-list."
                tunings
                pitches)
               '())))
-
      (if (null? predefined-fretboard)
          (let ((string-frets
                 (determine-frets-and-strings
                  notes
-                 defined-strings
+                 strings-used
+                 defined-fingers
                  (ly:context-property context 'minimumFret 0)
                  (ly:context-property context 'maximumFretStretch 4)
                  tunings)))
@@ -309,7 +333,12 @@ chords.  Returns a placement-list."
 
 
 (define (determine-frets-and-strings
-          notes defined-strings minimum-fret maximum-stretch tuning)
+          notes
+          defined-strings
+          defined-fingers
+          minimum-fret
+          maximum-stretch
+          tuning)
 
   (define (calc-fret pitch string tuning)
     (- (ly:pitch-semitones pitch) (list-ref tuning (1- string))))
@@ -329,7 +358,8 @@ chords.  Returns a placement-list."
             (let* ((num (ly:event-property art 'digit)))
 
               (if (and (eq? 'fingering-event (ly:event-property art 'class))
-                       (number? num))
+                       (number? num)
+                        (> num 0))
                   (set! finger-found num))))
           articulations)
 
@@ -341,6 +371,11 @@ chords.  Returns a placement-list."
           num
           #f)))
 
+  (define (finger-number event)
+    (let ((num (ly:event-property event 'digit)))
+      (if (number? num)
+          num
+          #f)))
 
   (define (delete-free-string string)
     (if (number? string)
@@ -359,7 +394,8 @@ chords.  Returns a placement-list."
             (and x y))
           #t
           (map (lambda (specced-fret)
-                 (> maximum-stretch (abs (- fret specced-fret))))
+                 (or (eq? 0 specced-fret)
+                     (>= maximum-stretch (abs (- fret specced-fret)))))
                specified-frets))))
 
   (define (string-qualifies string pitch)
@@ -367,6 +403,10 @@ chords.  Returns a placement-list."
       (and (>= fret minimum-fret)
           (close-enough fret))))
 
+  (define (open-string string pitch)
+    (let* ((fret (calc-fret pitch string tuning)))
+      (eq? fret 0)))
+
   (define string-fret-fingering-tuples '())
 
   (define (set-fret note string)
@@ -381,35 +421,62 @@ chords.  Returns a placement-list."
        (delete-free-string string)
        (set! specified-frets (cons this-fret specified-frets))))
 
+  (define (pad-list target template)
+    (while (< (length target) (length template))
+           (begin
+           (set! target (if (null? target)
+                            '(())
+                            (append target '(())))))
+    ))
+
   ;;; body of determine-frets-and-strings
   (set! free-strings (map 1+ (iota (length tuning))))
 
   ;; get defined-strings same length as notes
-  (while (< (length defined-strings) (length notes))
-         (set! defined-strings (append defined-strings '(()))))
+  (pad-list defined-strings notes)
+
+  ;; get defined-fingers same length as notes
+  (pad-list defined-fingers notes)
 
-  ;; handle notes with strings assigned
+  ;; handle notes with strings assigned and fingering of 0
   (for-each
-    (lambda (note string)
-      (if (null? string)
-          (set! unassigned-notes (cons note unassigned-notes))
-          (let ((this-string (string-number string)))
-            (delete-free-string this-string)
-            (set-fret note this-string))))
-    notes defined-strings)
+    (lambda (note string finger)
+      (let ((digit (if (null? finger)
+                       #f
+                       finger)))
+        (if (and (null? string)
+                 (not (eq? digit 0)))
+            (set! unassigned-notes (cons note unassigned-notes))
+            (if (eq? digit 0)
+                (let ((fit-string
+                      (find (lambda (string)
+                              (open-string string (note-pitch note)))
+                            free-strings)))
+                  (if fit-string
+                      (begin
+                        (delete-free-string fit-string)
+                        (set-fret note fit-string))
+                      (begin
+                        (ly:warning (_ "No open string for pitch ~a")
+                                       (note-pitch note))
+                        (set! unassigned-notes (cons note unassigned-notes)))))
+                (begin
+                  (delete-free-string string)
+                  (set-fret note string))))))
+    notes defined-strings defined-fingers)
 
   ;; handle notes without strings assigned
   (for-each
    (lambda (note)
-     (let* ((fit-string
-              (find (lambda (string)
-                      (string-qualifies string (note-pitch note)))
-                    free-strings)))
+     (let ((fit-string
+            (find (lambda (string)
+                    (string-qualifies string (note-pitch note)))
+                  free-strings)))
         (if fit-string
             (set-fret note fit-string)
-            (ly:warning "No string for pitch ~a (given frets ~a)"
-                        (note-pitch note)
-                        specified-frets))))
+            (ly:warning (_ "No string for pitch ~a (given frets ~a)")
+                           (note-pitch note)
+                           specified-frets))))
    (sort unassigned-notes note-pitch>?))
 
    string-fret-fingering-tuples)
@@ -431,10 +498,10 @@ chords.  Returns a placement-list."
     ((and (<= 0 fret-number) (< fret-number (length labels)))
      (list-ref labels fret-number))
     (else
-     (ly:warning "No label for fret ~a (on string ~a);
-only ~a fret labels provided"
-                 fret-number string-number (length labels))
-       ".")))))
+     (ly:warning (_ "No label for fret ~a (on string ~a);
+only ~a fret labels provided")
+                fret-number string-number (length labels))
+     ".")))))
 
 ;; Display the fret number as a number
 (define-public (fret-number-tablature-format