Approximates cross-staff slurs in VerticalAxisGroup vertical-skylines.

lily/slur.cc

 /*
   This file is part of LilyPond, the GNU music typesetter.
 
   Copyright (C) 1996--2012 Han-Wen Nienhuys <hanwen@xs4all.nl>
   Jan Nieuwenhuizen <janneke@gnu.org>
 
   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 127 matching lines @@
   Stencil *m = me->get_stencil ();
   return m ? ly_interval2scm (m->extent (Y_AXIS))
          : ly_interval2scm (Interval ());
 }
 
 MAKE_SCHEME_CALLBACK (Slur, print, 1);
 SCM
 Slur::print (SCM smob)
 {
   Grob *me = unsmob_grob (smob);
+
   extract_grob_set (me, "note-columns", encompasses);
   if (encompasses.empty ())
     {
       me->suicide ();
       return SCM_EOL;
     }
 
   Real staff_thick = Staff_symbol_referencer::line_thickness (me);
   Real base_thick = staff_thick
                     * robust_scm2double (me->get_property ("thickness"), 1);
@@ skipping 97 matching lines @@
 Slur::main_to_stub (Grob *main, Grob *stub)
 {
   extract_grob_set (main, "note-columns", nc);
   for (vsize i = 0; i < nc.size (); i++)
     add_column (stub, nc[i]);
 
   extract_grob_set (main, "encompass-objects", eo);
   for (vsize i = 0; i < eo.size (); i++)
     add_extra_encompass (stub, eo[i]);
 
-  stub->set_object ("surrogate", main->self_scm ());
-
   dynamic_cast<Spanner *> (stub)->set_bound
     (LEFT, dynamic_cast<Spanner *> (main)->get_bound (LEFT));
   dynamic_cast<Spanner *> (stub)->set_bound
     (RIGHT, dynamic_cast<Spanner *> (main)->get_bound (RIGHT));
-}
-
-MAKE_SCHEME_CALLBACK (Slur, direction_from_shadowed_slur, 1);
-SCM
-Slur::direction_from_shadowed_slur (SCM smob)
-{
-  Grob *me = unsmob_grob (smob);
-  if (Grob *slur = unsmob_grob (me->get_object ("surrogate")))
-    return scm_from_int (get_grob_direction (slur));
-
-  me->programming_error ("Cannot determine SlurStub direction");
-
-  return scm_from_int (UP);
 }
 
 MAKE_SCHEME_CALLBACK_WITH_OPTARGS (Slur, pure_outside_slur_callback, 4, 1, "");
 SCM
 Slur::pure_outside_slur_callback (SCM grob, SCM start_scm, SCM end_scm, SCM offset_scm)
 {
   int start = robust_scm2int (start_scm, 0);
   int end = robust_scm2int (end_scm, 0);
   Grob *script = unsmob_grob (grob);
   Grob *slur = unsmob_grob (script->get_object ("slur"));
@@ skipping 118 matching lines @@
     {
       Box b;
       b.add_point (curve.curve_point (i * 1.0 / box_count));
       b.add_point (curve.curve_point ((i + 1) * 1.0 / box_count));
       boxes.push_back (b);
     }
 
   return Skyline_pair (boxes, X_AXIS).smobbed_copy ();
 }
 
+/*
+ * USE ME ONLY FOR CROSS STAFF SLURS!
+ * We only want to keep the topmost skyline of the topmost axis group(s)
+ * and the bottommost skyline of the bottommost axis group(s). Otherwise,
+ * the VerticalAxisGroups will be spaced very far apart to accommodate the
+ * slur, which we don't want, as it is cross staff.
+ *
+ * TODO: Currently, the code below keeps the topmost and bottommost axis
+ * groups and gets rid of the rest.  This should be more nuanced for
+ * cases like ossias where the topmost staff changes over the course of
+ * the slur.  Ditto for the bottommost staff.
+ */
+
 MAKE_SCHEME_CALLBACK (Slur, extremal_stub_vertical_skylines, 1);
 SCM
 Slur::extremal_stub_vertical_skylines (SCM smob)
 {
   Grob *me = unsmob_grob (smob);
-  vector<int> vais;
-  extract_grob_set (me, "note-columns", note_columns);
-  for (vsize i = 0; i < note_columns.size (); i++)
-    vais.push_back (Grob::get_vertical_axis_group_index (note_columns[i]));
-
-  vector_sort (vais, less<int> ());
-  int my_vai = Grob::get_vertical_axis_group_index (me);
-  if (!(my_vai == vais[0] || my_vai == vais.back ()))
+  Grob *cause = unsmob_grob (me->get_property ("cause"));
+  if (!cause || !cause->is_live ())
+    {
+      me->suicide ();
+      return SCM_BOOL_F;
+    }
+
+  // triggers suicide if necessary
+  (void) me->get_property ("cross-staff");
+  if (!me->is_live ())
+    return SCM_BOOL_F;
+
+  Grob *my_vag = Grob::get_vertical_axis_group (me);
+  extract_grob_set (me, "note-columns", ro_note_columns);
+  vector<Grob *> note_columns (ro_note_columns);
+  vector_sort (note_columns, Grob::vertical_less);
+  bool highest = my_vag == Grob::get_vertical_axis_group (note_columns[0]);
+  bool lowest = my_vag == Grob::get_vertical_axis_group (note_columns.back ());
+  if (!highest && !lowest)
     return Skyline_pair ().smobbed_copy ();
 
   Skyline_pair sky = *Skyline_pair::unsmob (vertical_skylines (smob));
-  if (my_vai == vais[0])
-    sky[DOWN] = Skyline ();
+
+  if (highest)
+    sky[DOWN] = Skyline (DOWN);
   else
-    sky[UP] = Skyline ();
+    sky[UP] = Skyline (UP);
 
   return sky.smobbed_copy ();
 }
 
 /*
  * Used by Slur_engraver:: and Phrasing_slur_engraver::
  */
 void
 Slur::auxiliary_acknowledge_extra_object (Grob_info const &info,
-                                          vector<Grob *> &slurs,
-                                          vector<Grob *> &end_slurs)
-{
-  if (slurs.empty () && end_slurs.empty ())
+                                          vector<Slur_info> &slur_infos,
+                                          vector<Slur_info> &end_slur_infos)
+{
+  if (slur_infos.empty () && end_slur_infos.empty ())
     return;
 
   Grob *e = info.grob ();
   SCM avoid = e->get_property ("avoid-slur");
   Grob *slur;
-  if (end_slurs.size () && !slurs.size ())
-    slur = end_slurs[0];
+  if (end_slur_infos.size () && !slur_infos.size ())
+    slur = end_slur_infos[0].slur_;
   else
-    slur = slurs[0];
+    slur = slur_infos[0].slur_;
 
   if (Tie::has_interface (e)
       || avoid == ly_symbol2scm ("inside"))
     {
-      for (vsize i = slurs.size (); i--;)
-        add_extra_encompass (slurs[i], e);
-      for (vsize i = end_slurs.size (); i--;)
-        add_extra_encompass (end_slurs[i], e);
+      for (vsize i = slur_infos.size (); i--;)
+        add_extra_encompass (slur_infos[i].slur_, e);
+      for (vsize i = end_slur_infos.size (); i--;)
+        add_extra_encompass (end_slur_infos[i].slur_, e);
       if (slur)
         e->set_object ("slur", slur->self_scm ());
     }
   else if (avoid == ly_symbol2scm ("outside")
            || avoid == ly_symbol2scm ("around"))
     {
       if (slur)
         {
           chain_offset_callback (e, outside_slur_callback_proc, Y_AXIS);
           chain_callback (e, outside_slur_cross_staff_proc, ly_symbol2scm ("cross-staff"));
@@ skipping 131 matching lines @@
                "direction "
                "eccentricity "
                "encompass-objects "
                "height-limit "
                "inspect-quants "
                "inspect-index "
                "line-thickness "
                "note-columns "
                "positions "
                "ratio "
                "thickness "

[dak, 2012/09/02 15:59:00]

No entry for "surrogate"?

[MikeSol, 2012/09/02 16:45:14]

scm/define-grob-interfaces.scm

               );