Approximates cross-staff slurs in VerticalAxisGroup vertical-skylines.

lily/slur-engraver.cc

 /*
   This file is part of LilyPond, the GNU music typesetter.
 
   Copyright (C) 1997--2012 Han-Wen Nienhuys <hanwen@xs4all.nl>
 
   LilyPond is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.
 
@@ skipping 53 matching lines @@
   void set_melisma (bool);
 
 protected:
   DECLARE_TRANSLATOR_LISTENER (slur);
   DECLARE_ACKNOWLEDGER (inline_accidental);
   DECLARE_ACKNOWLEDGER (fingering);
   DECLARE_ACKNOWLEDGER (note_column);
   DECLARE_ACKNOWLEDGER (script);
   DECLARE_ACKNOWLEDGER (dots);
   DECLARE_ACKNOWLEDGER (text_script);
-  DECLARE_ACKNOWLEDGER (tie);
+  DECLARE_END_ACKNOWLEDGER (tie);
   DECLARE_ACKNOWLEDGER (tuplet_number);
 
   void acknowledge_extra_object (Grob_info);
   void stop_translation_timestep ();
   void process_music ();
 
   virtual void finalize ();
   virtual void derived_mark () const;
 
 public:
@@ skipping 28 matching lines @@
 
 void
 Slur_engraver::set_melisma (bool m)
 {
   context ()->set_property ("slurMelismaBusy", m ? SCM_BOOL_T : SCM_BOOL_F);
 }
 
 void
 Slur_engraver::acknowledge_note_column (Grob_info info)
 {
+  /*
+   * For every active slur, we create a slur stub.
+   * As we do not yet know what vertical axis groups note columns belong to,
+   * we create a stub for each note and then suicide duplicate stubs on
+   * axis groups.
+   * These slurs should be used ONLY to approximate cross-staff slurs
+   * in vertical skylines.
+   */
+··
   Grob *e = info.grob ();
   for (vsize i = slur_infos_.size (); i--;)
     {
       Slur::add_column (slur_infos_[i].slur_, e);
-      Grob *stub = make_spanner ("SlurStub", info.grob ()->self_scm ());
+      Grob *stub = make_spanner ("SlurStub", slur_infos_[i].slur_->self_scm ());
       slur_infos_[i].stubs_.push_back (stub);
     }
   for (vsize i = end_slur_infos_.size (); i--;)
     {
       Slur::add_column (end_slur_infos_[i].slur_, e);
-      Grob *stub = make_spanner ("SlurStub", info.grob ()->self_scm ());
+      Grob *stub = make_spanner ("SlurStub", slur_infos_[i].slur_->self_scm ());
       end_slur_infos_[i].stubs_.push_back (stub);
     }
 }
 
 void
 Slur_engraver::acknowledge_extra_object (Grob_info info)
 {
   objects_to_acknowledge_.push_back (info);
 }
 
@@ skipping 28 matching lines @@
     acknowledge_extra_object (info);
 }
 
 void
 Slur_engraver::acknowledge_text_script (Grob_info info)
 {
   acknowledge_extra_object (info);
 }
 
 void
-Slur_engraver::acknowledge_tie (Grob_info info)
+Slur_engraver::acknowledge_end_tie (Grob_info info)
 {
   acknowledge_extra_object (info);
 }
 
 void
 Slur_engraver::finalize ()
 {
   for (vsize i = 0; i < slur_infos_.size (); i++)
     {
       slur_infos_[i].slur_->warning (_ ("unterminated slur"));
@@ skipping 135 matching lines @@
       if (!s->get_bound (RIGHT))
         s->set_bound (RIGHT, unsmob_grob (get_property ("currentMusicalColumn")));
       announce_end_grob (s, SCM_EOL);
     }
 
   for (vsize i = 0; i < objects_to_acknowledge_.size (); i++)
     Slur::auxiliary_acknowledge_extra_object (objects_to_acknowledge_[i], slur_infos_, end_slur_infos_);
 
   for (vsize i = 0; i < end_slur_infos_.size (); i++)
     {
-      // There are likely SlurStubs we don't need. Get rid of them.
+      // There are likely SlurStubs we don't need. Get rid of them
+      // and only keep one per VerticalAxisGroup.
       vector<Grob *> vags;
       vector<Grob *> stubs;
       for (vsize j = 0; j < end_slur_infos_[i].stubs_.size (); j++)
         {
           Grob *stub = end_slur_infos_[i].stubs_[j];
           Grob *vag = Grob::get_vertical_axis_group (stub);
           if (vag)
             {
               vector<Grob *>::const_iterator it =
                 find (vags.begin (), vags.end (), vag);
@@ skipping 20 matching lines @@
   start_events_.clear ();
   stop_events_.clear ();
 }
 
 ADD_ACKNOWLEDGER (Slur_engraver, inline_accidental);
 ADD_ACKNOWLEDGER (Slur_engraver, fingering);
 ADD_ACKNOWLEDGER (Slur_engraver, note_column);
 ADD_ACKNOWLEDGER (Slur_engraver, script);
 ADD_ACKNOWLEDGER (Slur_engraver, text_script);
 ADD_ACKNOWLEDGER (Slur_engraver, dots);
-ADD_ACKNOWLEDGER (Slur_engraver, tie);
+ADD_END_ACKNOWLEDGER (Slur_engraver, tie);
 ADD_ACKNOWLEDGER (Slur_engraver, tuplet_number);
 ADD_TRANSLATOR (Slur_engraver,
                 /* doc */
                 "Build slur grobs from slur events.",
 
                 /* create */
                 "Slur ",
 
                 /* read */
                 "slurMelismaBusy "
                 "doubleSlurs ",
 
                 /* write */
                 ""
                );