lilypond-1.3.112

diff --git a/input/test/follow-thread.ly b/input/test/follow-thread.ly
new file mode 100644 (file)
index 0000000..d0df4d3
--- /dev/null
+++ b/input/test/follow-thread.ly
@@ -0,0 +1,27 @@
+% followThread: connect note heads with line when thread switches staff 
+
+\score{
+    \context PianoStaff <
+        \context Staff=one \notes\relative c''{
+           \context Thread
+            a
+           \translator Staff=two
+           a,
+
+% smaller = easier to debug.
+%{     a
+           \translator Staff=one
+           a''
+%}
+               s2
+       }
+       \context Staff=two { \clef bass; \skip 1; }
+    >
+    \paper{
+        linewidth = 70.\mm;
+       \translator {
+           \ScoreContext
+           followThread = ##t
+       }
+    }
+}

diff --git a/lily/note-head-line-engraver.cc b/lily/note-head-line-engraver.cc
new file mode 100644 (file)
index 0000000..57e62f5
--- /dev/null
+++ b/lily/note-head-line-engraver.cc
@@ -0,0 +1,131 @@
+/*   
+  note-head-line-engraver.cc -- implement Note_head_line_engraver
+  
+  source file of the GNU LilyPond music typesetter
+  
+  (c) 2000 Jan Nieuwenhuizen <janneke@gnu.org>
+ */
+
+#include "engraver.hh"
+#include "group-interface.hh"
+#include "item.hh"
+#include "musical-request.hh"
+#include "spanner.hh"
+#include "rhythmic-head.hh"
+#include "side-position-interface.hh"
+#include "staff-symbol-referencer.hh"
+#include "translator-group.hh"
+
+/**
+   Create line-spanner grobs for glissandi (and possibly other) lines
+   that connect note heads.
+ */
+
+class Note_head_line_engraver : public Engraver
+{
+public:
+  VIRTUAL_COPY_CONS (Translator);
+  Note_head_line_engraver ();
+
+protected:
+  virtual void acknowledge_grob (Grob_info);
+  virtual void create_grobs ();
+  virtual void stop_translation_timestep ();
+  virtual bool try_music (Music *);
+
+private:
+  Spanner* line_; 
+  Request* req_;
+  Request* last_req_;
+  Translator* last_staff_;
+  Grob* head_;
+  Grob* last_head_;
+};
+
+Note_head_line_engraver::Note_head_line_engraver ()
+{
+  line_ = 0;
+  req_ = 0;
+  last_req_ = 0;
+  head_ = 0;
+  last_head_ = 0;
+  last_staff_ = 0;
+}
+
+bool
+Note_head_line_engraver::try_music (Music* m)
+{
+  if (!req_)
+    {
+      if (Glissando_req *r = dynamic_cast<Glissando_req*> (m))
+       {
+         req_ = r;
+         return true;
+       }
+    }
+  return false;
+}
+
+void
+Note_head_line_engraver::acknowledge_grob (Grob_info info)
+{
+  if (Rhythmic_head::has_interface (info.elem_l_))
+    {
+      last_head_ = head_;
+      head_ = info.elem_l_;
+      if (to_boolean (get_property ("followThread")))
+       {
+         Translator* staff = daddy_trans_l_ && daddy_trans_l_->daddy_trans_l_
+           ? daddy_trans_l_->daddy_trans_l_->daddy_trans_l_ : 0;
+         if (staff != last_staff_)
+           {
+             if (last_head_)
+               last_req_ = (Request*)1; // ugh
+             last_staff_ = staff;
+           }
+       }
+    }
+}
+
+void
+Note_head_line_engraver::create_grobs ()
+{
+  if (!line_ && last_req_ && last_head_ && head_)
+    {
+      /* type Glissando? */
+      line_ = new Spanner (get_property ("NoteHeadLine"));
+      line_->set_bound (RIGHT, head_);
+      line_->set_bound (LEFT, last_head_);
+
+      line_->set_parent (head_, X_AXIS);
+      line_->set_parent (head_, Y_AXIS);
+
+      line_->set_parent (last_head_, X_AXIS);
+      line_->set_parent (last_head_, Y_AXIS);
+
+      if ((int)last_req_ == 1) // ugh
+       last_req_ = 0;
+      
+      announce_grob (line_, last_req_);
+      last_req_ = 0;
+      last_head_ = head_;
+      head_ = 0;
+    }
+}
+
+void
+Note_head_line_engraver::stop_translation_timestep ()
+{
+  if (line_)
+    {
+      typeset_grob (line_);
+      line_ = 0;
+    }
+  if (req_)
+    last_req_ = req_;
+  req_ = 0;
+}
+
+
+ADD_THIS_TRANSLATOR (Note_head_line_engraver);
+