X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Fslur.cc;h=bade56d2e36438cc51cb7ddeb81951bf3340cbeb;hb=1f0d3e5ed0e3b1f0a21a7d64e5b9c7e27bba4f5a;hp=3ca85469ceee0c78f39a57ecc0a1dd33157308f7;hpb=fb807693067f854df3b2bd1f28456fe8955a7330;p=lilypond.git

diff --git a/lily/slur.cc b/lily/slur.cc
index 3ca85469ce..bade56d2e3 100644
--- a/lily/slur.cc
+++ b/lily/slur.cc
@@ -3,15 +3,22 @@
 
   source file of the GNU LilyPond music typesetter
 
-  (c) 1996--2000 Han-Wen Nienhuys <hanwen@cs.uu.nl>
+  (c) 1996--2002 Han-Wen Nienhuys <hanwen@cs.uu.nl>
     Jan Nieuwenhuizen <janneke@gnu.org>
 */
 
 /*
   [TODO]
+  
+    * should avoid stafflines with horizontal part.
+
     * begin and end should be treated as a/acknowledge Scripts.
-    * broken slur should have uniform trend
-    * smart changing of endings and offsets to avoid ugly beziers.
+
+    * smart changing of endings
+
+    * smart changing of (Y-?)offsets to avoid ugly beziers
+ (along-side-stem)
+ 
  */
 
 #include "directional-element-interface.hh"
@@ -23,48 +30,52 @@
 #include "stem.hh"
 #include "paper-column.hh"
 #include "molecule.hh"
-#include "debug.hh"
+#include "warn.hh"
 #include "slur-bezier-bow.hh"
 #include "main.hh"
-#include "cross-staff.hh"
 #include "group-interface.hh"
 #include "staff-symbol-referencer.hh"
+#include "spanner.hh"
 
-Slur::Slur (SCM s)
-  : Spanner (s)
+
+void
+Slur::set_interface (Grob*me)
 {
-  set_elt_property ("attachment", gh_cons (SCM_BOOL_F, SCM_BOOL_F));
-  set_elt_pointer ("note-columns", SCM_EOL);
-  set_elt_property ("control-points", SCM_EOL);
+  /* Copy to mutable list. */
+  me->set_grob_property ("attachment",
+			 ly_deep_copy (me->get_grob_property ("attachment")));
 }
 
 void
-Slur::add_column (Note_column*n)
+Slur::add_column (Grob*me, Grob*n)
 {
-  if (!gh_pair_p (n->get_elt_pointer ("note-heads")))
-    warning (_ ("Putting slur over rest.  Ignoring."));
-  else
-    {
-      Pointer_group_interface (this, "note-columns").add_element (n);
-      add_dependency (n);
-    }
+  if (!gh_pair_p (n->get_grob_property ("note-heads")))
+    me->warning (_ ("Putting slur over rest."));
+
+  Pointer_group_interface::add_grob (me, ly_symbol2scm ("note-columns"), n);
+  me->add_dependency (n);
+
+  add_bound_item (dynamic_cast<Spanner*> (me), dynamic_cast<Item*> (n));
 }
 
 void
-Slur::de_uglyfy (Slur_bezier_bow* bb, Real default_height)
+Slur::de_uglyfy (Grob*me, Slur_bezier_bow* bb, Real default_height)
 {
   Real length = bb->curve_.control_[3][X_AXIS] ; 
   Real ff = bb->fit_factor ();
   for (int i = 1; i < 3; i++)
     {
-      Real ind = abs (bb->curve_.control_[(i-1)*3][X_AXIS]
+      Real ind = abs (bb->curve_.control_[ (i-1)*3][X_AXIS]
 		      - bb->curve_.control_[i][X_AXIS]) / length;
       Real h = bb->curve_.control_[i][Y_AXIS] * ff / length;
 
       Real f = default_height / length;
-      Real c1 = paper_l ()->get_var ("bezier_control1");
-      Real c2 = paper_l ()->get_var ("bezier_control2");
-      Real c3 = paper_l ()->get_var ("bezier_control3");
+      SCM up = me->get_grob_property ("de-uglify-parameters");
+      
+      Real c1 = gh_scm2double (ly_car (up));
+      Real c2 = gh_scm2double (ly_cadr (up));
+      Real c3 = gh_scm2double (ly_caddr (up)); 
+      
       if (h > c1 * f)
 	{
 	  h = c1 * f; 
@@ -80,16 +91,18 @@ Slur::de_uglyfy (Slur_bezier_bow* bb, Real default_height)
   bb->curve_.assert_sanity ();
 }
 
+
+
 Direction
-Slur::get_default_dir () const
+Slur::get_default_dir (Grob*me) 
 {
-  Link_array<Note_column> encompass_arr =
-    Pointer_group_interface__extract_elements (this, (Note_column*)0, "note-columns");
+  Link_array<Grob> encompasses =
+    Pointer_group_interface__extract_grobs (me, (Grob*)0, "note-columns");
   
   Direction d = DOWN;
-  for (int i=0; i < encompass_arr.size (); i ++) 
+  for (int i=0; i < encompasses.size (); i ++) 
     {
-      if (encompass_arr[i]->dir () < 0) 
+      if (Note_column::dir (encompasses[i]) < 0) 
 	{
 	  d = UP;
 	  break;
@@ -98,341 +111,509 @@ Slur::get_default_dir () const
   return d;
 }
 
-void
-Slur::do_add_processing ()
-{
-  Link_array<Note_column> encompass_arr =
-    Pointer_group_interface__extract_elements (this, (Note_column*)0, "note-columns");
 
-  if (encompass_arr.size ())
+MAKE_SCHEME_CALLBACK (Slur, after_line_breaking,1);
+SCM
+Slur::after_line_breaking (SCM smob)
+{
+  Grob *me = unsmob_grob (smob);
+  if (!scm_ilength (me->get_grob_property ("note-columns")))
     {
-      set_bound (LEFT, encompass_arr[0]);    
-      if (encompass_arr.size () > 1)
-	set_bound (RIGHT, encompass_arr.top ());
+      me->suicide ();
+      return SCM_UNSPECIFIED;
     }
-}
-
+  set_extremities (me);
+  set_control_points (me);
+  return SCM_UNSPECIFIED;
+} 
 
 
-Offset
-Slur::encompass_offset (Note_column const* col) const
+void
+Slur::check_slope (Grob *me)
 {
-  Offset o;
-  Stem* stem_l = col->stem_l ();
-  Direction dir = directional_element (this).get ();
-  
-  if (!stem_l)
-    {
-      warning (_ ("Slur over rest?"));
-     o[X_AXIS] = col->relative_coordinate (0, X_AXIS);
-      o[Y_AXIS] = col->extent (Y_AXIS)[dir];
-      return o;  
-    }
-  Direction stem_dir = directional_element (stem_l).get ();
-  o[X_AXIS] = stem_l->relative_coordinate (0, X_AXIS);
 
   /*
-    Simply set x to middle of notehead
+    Avoid too steep slurs.
    */
+  SCM s = me->get_grob_property ("slope-limit");
+  if (gh_number_p (s))
+    {
+      Array<Offset> encompass = get_encompass_offsets (me);
+      Drul_array<Offset> attachment;
+      attachment[LEFT] = encompass[0];
+      attachment[RIGHT] = encompass.top ();
+
+      Real dx = attachment[RIGHT][X_AXIS] - attachment[LEFT][X_AXIS];
+      Real dy = attachment[RIGHT][Y_AXIS] - attachment[LEFT][Y_AXIS];
+      if (!dx)
+	return;
+      
+      Real slope = slope = abs (dy / dx);
 
-  o[X_AXIS] -= 0.5 * stem_dir * col->extent (X_AXIS).length ();
+      Real limit = gh_scm2double (s);
 
-  if ((stem_dir == dir)
-      && !stem_l->extent (Y_AXIS).empty_b ())
-    {
-      o[Y_AXIS] = stem_l->extent (Y_AXIS)[dir];
-    }
-  else
-    {
-      o[Y_AXIS] = col->extent (Y_AXIS)[dir];
+      if (slope > limit)
+	{
+	  Real staff_space = Staff_symbol_referencer::staff_space ((Grob*)me);
+	  Direction dir = (Direction)gh_scm2int (me->get_grob_property ("direction"));
+	  Direction d = (Direction) (- dir * (sign (dy)));
+	  SCM a = me->get_grob_property ("attachment-offset");
+	  Drul_array<Offset> o;
+	  o[LEFT] = ly_scm2offset (index_get_cell (a, LEFT));
+	  o[RIGHT] = ly_scm2offset (index_get_cell (a, RIGHT));
+	  o[d][Y_AXIS] -= (limit - slope) * dx * dir / staff_space;
+
+	  o[d][Y_AXIS] *= Directional_element_interface::get (me);
+
+	  me->set_grob_property ("attachment-offset",
+				gh_cons (ly_offset2scm (o[LEFT]),
+					 ly_offset2scm (o[RIGHT])));
+	}
     }
 
-  /*
-   leave a gap: slur mustn't touch head/stem
-   */
-  o[Y_AXIS] += dir * paper_l ()->get_var ("slur_y_free");
-  o[Y_AXIS] -= calc_interstaff_dist (stem_l, this);
-  return o;
 }
 
-GLUE_SCORE_ELEMENT(Slur,after_line_breaking);
-
+/*
+  Set 'attachment grob property, and return it.
+*/
 SCM
-Slur::member_after_line_breaking ()
+Slur::set_extremities (Grob *me)
 {
-  set_extremities ();
-  set_control_points ();
-  return SCM_UNDEFINED;
-} 
+  if (!Directional_element_interface::get (me))
+    Directional_element_interface::set (me, get_default_dir (me));
 
-SCM
-slur_get_bound (SCM slur, SCM dir)
-{
-  return ((Slur*)unsmob_element (slur))->get_bound (to_dir (dir))->self_scm_;
-}
+  SCM att = me->get_grob_property ("attachment");
+      /*
+       */
+      if (!gh_pair_p (att))
+	{
+	  programming_error ("attachment is not a cons?!");
+	  att = gh_cons (SCM_EOL, SCM_EOL);
+	  me->set_grob_property ("attachment", att);
+	}
+      
+  Direction dir = LEFT;
+  do 
+    {
+    
+      if (!gh_symbol_p (index_get_cell (att, dir)))
+	{
+	  for (SCM s = me->get_grob_property ("extremity-rules");
+	       s != SCM_EOL; s = ly_cdr (s))
+	    {
+	      SCM r = gh_call2 (ly_caar (s), me->self_scm (),
+				 gh_int2scm ((int)dir));
+	      if (r != SCM_BOOL_F)
+		{
+		  index_set_cell (att, dir,
+				  ly_cdar (s));
+		  break;
+		}
+	    }
+	}
+    }
+  while (flip (&dir) != LEFT);
 
-SCM
-score_element_get_pointer (SCM se, SCM name)
-{
-  SCM s = scm_assq (name, unsmob_element (se)->pointer_alist_);
-  return (s == SCM_BOOL_F) ? SCM_UNDEFINED : gh_cdr (s); 
-}
+  check_slope (me);
 
-SCM
-score_element_get_property (SCM se, SCM name)
-{
-  SCM s = scm_assq (name, unsmob_element (se)->property_alist_);
-  return (s == SCM_BOOL_F) ? SCM_UNDEFINED : gh_cdr (s); 
+  return att;
 }
 
-void
-init_score_elts ()
+
+Real
+Slur::get_first_notecolumn_y (Grob *me, Direction dir)
 {
-  scm_make_gsubr ("get-pointer", 2 , 0, 0,  
-		  (SCM(*)(...)) score_element_get_pointer);
-  scm_make_gsubr ("get-property", 2 , 0, 0,  
-		  (SCM(*)(...)) score_element_get_property);
-  scm_make_gsubr ("get-bound", 2 , 0, 0,  
-		  (SCM(*)(...)) slur_get_bound);
-}
+  SCM cols = me->get_grob_property ("note-columns");
 
-ADD_SCM_INIT_FUNC (score_elt, init_score_elts);
+  if(!gh_pair_p (cols))
+    {
+      programming_error ("No note-columns in slur?");
+      me->suicide ();
+      return 0.0;
+    }
+  
+  if (dir == LEFT)
+    cols = scm_reverse(cols);
+  
+  Grob *col = unsmob_grob (ly_car (cols));
+  Grob *common[] =
+  {
+    0,
+    me->common_refpoint (col, Y_AXIS)
+  };
+  Real y;
+  if (col == ((Spanner*)me)->get_bound (dir))
+    {
+      y = get_attachment (me, dir, common)[Y_AXIS];
+    }
+  else
+    {
+      y = encompass_offset (me, col, common)[Y_AXIS]
+	- me->relative_coordinate (common[Y_AXIS], Y_AXIS); 
+    }
+  return y;
+}
 
-void
-Slur::set_extremities ()
+Offset
+Slur::broken_trend_offset (Grob *me, Direction dir)
 {
-  if (!directional_element (this).get ())
-    directional_element (this).set (get_default_dir ());
-
-  Direction dir = LEFT;
-  do 
+  /*
+    A broken slur should maintain the same vertical trend
+    the unbroken slur would have had.
+  */
+  Offset o;
+  if (Spanner *mother =  dynamic_cast<Spanner*> (me->original_))
     {
-      if (!gh_symbol_p (index_cell (get_elt_property ("attachment"), dir)))
+      for (int i = dir == LEFT ? 0 : mother->broken_intos_.size () - 1;
+	   dir == LEFT ? i < mother->broken_intos_.size () : i > 0;
+	   dir == LEFT ? i++ : i--)
 	{
-	  
-	  // for (SCM s = get_elt_property ("slur-extremity-rules"); s != SCM_EOL; s = gh_cdr (s))
-	  for (SCM s = scm_eval (ly_symbol2scm ("slur-extremity-rules"));
-	       s != SCM_EOL; s = gh_cdr (s))
+	  if (mother->broken_intos_[i - dir] == me)
 	    {
-	      SCM r = scm_eval (scm_listify (gh_caar (s),
-					     this->self_scm_,
-					     gh_int2scm ((int)dir),
-					     SCM_UNDEFINED));
-	      if (r != SCM_BOOL_F)
-		{
-		  index_set_cell (get_elt_property ("attachment"), dir,
-				  gh_cdar (s));
-		  break;
-		}
+	      Grob *neighbour = mother->broken_intos_[i];
+	      if (dir == RIGHT)
+		neighbour->set_grob_property ("direction",
+					     me->get_grob_property ("direction"));
+	      Real neighbour_y = get_first_notecolumn_y (neighbour, dir);
+	      Real y = get_first_notecolumn_y (me, -dir);
+	      int neighbour_cols = scm_ilength (neighbour->get_grob_property ("note-columns"));
+	      int cols = scm_ilength (me->get_grob_property ("note-columns"));
+	      o = Offset (0, (y*neighbour_cols + neighbour_y*cols) /
+ (cols + neighbour_cols));
+	      break;
 	    }
 	}
     }
-  while (flip (&dir) != LEFT);
+  return o;
 }
 
+/*
+  COMMON is size-2 array with common refpoints.
+
+UGH: this routine delivers offsets which are *not* relative to COMMON.
+*/ 
 Offset
-Slur::get_attachment (Direction dir) const
+Slur::get_attachment (Grob *me, Direction dir,
+		      Grob **common) 
 {
-  SCM s = get_elt_property ("attachment");
-  SCM a = dir == LEFT ? gh_car (s) : gh_cdr (s);
-  Real ss = Staff_symbol_referencer_interface (this).staff_space ();
-  Real hs = ss / 2.0;
+  SCM s = me->get_grob_property ("attachment");
+  if (!gh_symbol_p (index_get_cell (s, dir)))
+    {
+      s = set_extremities (me);
+    }
+  
+  SCM a = dir == LEFT ? ly_car (s) : ly_cdr (s);
+  Spanner*sp = dynamic_cast<Spanner*> (me);
+  String str = ly_symbol2string (a);
+  Real staff_space = Staff_symbol_referencer::staff_space ((Grob*)me);
+  Real hs = staff_space / 2.0;
   Offset o;
-  if (Note_column* n = dynamic_cast<Note_column*> (get_bound (dir)))
+  
+  int slurdir = gh_scm2int (me->get_grob_property ("direction"));
+  
+  Grob *stem = 0;
+  if (Note_column::has_interface (sp->get_bound (dir)))
     {
-      if (Stem* st = dynamic_cast<Stem*> (n->stem_l ()))
+      Grob * n =sp->get_bound (dir);
+      if ((stem = Note_column::get_stem (n)))
 	{
-	  String str = ly_symbol2string (a);
+	  Real x_extent;
+	  if (Grob *head = Note_column::first_head (n))
+	    x_extent = head->extent (head, X_AXIS).length ();
+	  else
+	    x_extent = n->extent (n, X_AXIS).length ();
+
 	  if (str == "head")
 	    {
-	      o = Offset (0, st->chord_start_f ());
+	      o = Offset (0, Stem::head_positions (stem)
+			  [Directional_element_interface::get (me)] * hs);
 	      /*
 		Default position is centered in X, on outer side of head Y
 	       */
-	      o += Offset (0.5 * n->extent (X_AXIS).length (),
-			   0.5 * ss * directional_element (this).get ());
+	      o += Offset (0.5 * x_extent,
+			   0.5 * staff_space
+			   * Directional_element_interface::get (me));
 	    }
 	  else if (str == "alongside-stem")
 	    {
-	      o = Offset (0, st->chord_start_f ());
+	      o = Offset (0, Stem::chord_start_y (stem));
 	      /*
 		Default position is on stem X, on outer side of head Y
 	       */
-	      o += Offset (n->extent (X_AXIS).length ()
-			   * (1 + st->get_direction ()),
-			   0.5 * ss * directional_element (this).get ());
+	      o += Offset (x_extent * (1 + Stem::get_direction (stem)),
+			   0.5 * staff_space
+			   * Directional_element_interface::get (me));
 	    }
 	  else if (str == "stem")
 	    {
-	      o = Offset (0, st->stem_end_position () * hs);
+	      o = Offset (0, Stem::stem_end_position (stem) * hs);
 	      /*
 		Default position is on stem X, at stem end Y
 	       */
+	      Real stem_thickness =
+		gh_scm2double (stem->get_grob_property ("thickness"))
+		* stem->get_paper ()->get_var ("linethickness");
 	      o += Offset (0.5 *
-			   (n->extent (X_AXIS).length ()
-			    - st->extent (X_AXIS).length ())
-			    * (1 + st->get_direction ()),
-			    0);
-	    }
-	  else if (str == "loose-end")
-	    {
-	      SCM other_a = dir == LEFT ? gh_cdr (s) : gh_car (s);
-	      if (ly_symbol2string (other_a) != "loose-end")
-		{
-		  o = Offset (0, get_attachment (-dir)[Y_AXIS]);
-		}
-	    }
-
-	  
-	  SCM l = scm_assoc
-	    (scm_listify (a,
-			  gh_int2scm (st->get_direction () * dir),
-			  gh_int2scm (directional_element (this).get () * dir),
-			  SCM_UNDEFINED),
-	     scm_eval (ly_symbol2scm ("slur-extremity-offset-alist")));
-	  
-	  if (l != SCM_BOOL_F)
-	    {
-	      o += ly_scm2offset (gh_cdr (l)) * ss * dir;
+			   x_extent * (1 + Stem::get_direction (stem))
+			   - ((dir + 1)/2) * stem_thickness
+			   + ((1 - slurdir)/2) * stem_thickness,
+			   0);
 	    }
 	}
     }
-  
+  /*
+    If we're not a note_column, we can't be anything but a loose-end.
+    But if user has set (attachment . (stem . stem)), our string is
+    stem, not loose-end.
+
+    Hmm, maybe after-line-breaking should set this to loose-end?  */
+  else // if (str == "loose-end")
+    {
+      SCM other_a = dir == LEFT ? ly_cdr (s) : ly_car (s);
+      if (ly_symbol2string (other_a) != "loose-end")
+	o = broken_trend_offset (me, dir);
+    }
+
+  SCM alist = me->get_grob_property ("extremity-offset-alist");
+  int stemdir = stem ? Stem::get_direction (stem) : 1;
+  SCM l = scm_assoc
+    (scm_list_n (a,
+		  gh_int2scm (stemdir * dir),
+		  gh_int2scm (slurdir * dir),
+                  SCM_UNDEFINED), alist);
+
+  if (l != SCM_BOOL_F)
+    {
+      Offset off = ly_scm2offset (ly_cdr (l)) * staff_space;
+      off[X_AXIS] *= dir;
+      off[Y_AXIS] *= Directional_element_interface::get (me);
+      o += off;
+    }
+
+  /*
+    What if get_bound () is not a note-column?
+   */
+  if (str != "loose-end"
+      && sp->get_bound (dir)->common_refpoint (common[Y_AXIS], Y_AXIS) == common[Y_AXIS])
+    {      
+      o[Y_AXIS] += sp->get_bound (dir)->relative_coordinate (common[Y_AXIS], Y_AXIS) 
+	- me->relative_coordinate (common[Y_AXIS], Y_AXIS);
+    }
+
+  Offset off = ly_scm2offset (index_get_cell (me->get_grob_property
+					  ("attachment-offset"),
+					  dir)) * staff_space;
+
+  off[Y_AXIS] *= Directional_element_interface::get (me);
+  o += off;
   return o;
 }
 
-int
-Slur::cross_staff_count ()const
+Offset
+Slur::encompass_offset (Grob*me,
+			Grob* col,
+			Grob **common) 
 {
-  Link_array<Note_column> encompass_arr =
-    Pointer_group_interface__extract_elements (this, (Note_column*)0, "note-columns");
+  Offset o;
+  Grob* stem = unsmob_grob (col->get_grob_property ("stem"));
+  
+  Direction dir = Directional_element_interface::get (me);
+  
+  if (!stem)
+    {
+      me->warning (_ ("Slur over rest?"));
+      o[X_AXIS] = col->relative_coordinate (common[X_AXIS], X_AXIS);
+      o[Y_AXIS] = col->relative_coordinate (common[Y_AXIS], Y_AXIS);
+      return o;  
+    }
+  Direction stem_dir = Directional_element_interface::get (stem);
+  o[X_AXIS] = stem->relative_coordinate (0, X_AXIS);
 
-  int k=0;
+  /*
+    Simply set x to middle of notehead
+   */
+  Real x_extent;
+  if (Grob *head = Note_column::first_head (col))
+    x_extent = head->extent (head, X_AXIS).length ();
+  else
+    x_extent = col->extent (col, X_AXIS).length ();
+  o[X_AXIS] -= 0.5 * stem_dir * x_extent;
 
-  for (int i = 0; i < encompass_arr.size (); i++)
+  if ((stem_dir == dir)
+      && !stem->extent (stem, Y_AXIS).empty_b ())
     {
-      if (calc_interstaff_dist (encompass_arr[i], this))
-	k++;
+      o[Y_AXIS] = stem->extent (common[Y_AXIS], Y_AXIS)[dir];
+    }
+  else
+    {
+      o[Y_AXIS] = col->extent (common[Y_AXIS], Y_AXIS)[dir];
     }
-  return k;
-}
 
+  /*
+   leave a gap: slur mustn't touch head/stem
+   */
+  o[Y_AXIS] += dir * gh_scm2double (me->get_grob_property ("y-free")) *
+    1.0;
+  return o;
+}
 
 Array<Offset>
-Slur::get_encompass_offset_arr () const
+Slur::get_encompass_offsets (Grob *me)
 {
-  Link_array<Note_column> encompass_arr =
-    Pointer_group_interface__extract_elements (this, (Note_column*)0, "note-columns");
+  Spanner*sp = dynamic_cast<Spanner*> (me);
+  SCM eltlist = me->get_grob_property ("note-columns");
+  Grob *common[] = {common_refpoint_of_list (eltlist, me, X_AXIS),
+		    common_refpoint_of_list (eltlist, me, Y_AXIS)};
+
+
+  common[X_AXIS] = common[X_AXIS]->common_refpoint (sp->get_bound (RIGHT), X_AXIS);
+  common[X_AXIS] = common[X_AXIS]->common_refpoint (sp->get_bound (LEFT), X_AXIS);
   
-  Array<Offset> offset_arr;
+  Link_array<Grob>  encompasses = ly_scm2grobs (eltlist);
+  Array<Offset> offsets;
 
-  Offset origin (relative_coordinate (0, X_AXIS), 0);
+  Offset origin (me->relative_coordinate (common[X_AXIS], X_AXIS),
+		 me->relative_coordinate (common[Y_AXIS], Y_AXIS)); 
 
   int first = 1;
-  int last = encompass_arr.size () - 2;
+  int last = encompasses.size () - 2;
 
-  offset_arr.push (get_attachment (LEFT));
+  offsets.push (get_attachment (me, LEFT, common));
 
   /*
     left is broken edge
   */
-  int cross_count  = cross_staff_count ();
-  bool cross_b = cross_count && cross_count < encompass_arr.size ();
-  if (encompass_arr[0] != get_bound (LEFT))
+  if (encompasses[0] != sp->get_bound (LEFT))
     {
       first--;
-      Real is   = calc_interstaff_dist (encompass_arr[0], this);
-      if (cross_b)
-	offset_arr[0][Y_AXIS] += is;
+
+      // ?
+      offsets[0][Y_AXIS] -=
+	encompasses[0]->relative_coordinate (common[Y_AXIS], Y_AXIS) 
+	- me->relative_coordinate (common[Y_AXIS], Y_AXIS); 
     }
 
   /*
     right is broken edge
   */
-  if (encompass_arr.top () != get_bound (RIGHT))
+  if (encompasses.top () != sp->get_bound (RIGHT))
     {
       last++;
     }
 
   for (int i = first; i <= last; i++)
     {
-      Offset o (encompass_offset (encompass_arr[i]));
-      offset_arr.push (o - origin);
+      Offset o (encompass_offset (me, encompasses[i], common));
+      offsets.push (o - origin);
     }
 
-  offset_arr.push (Offset (spanner_length (), 0) + get_attachment (RIGHT));
+  offsets.push (Offset (sp->spanner_length (), 0) + get_attachment (me, RIGHT,common));
+
+  if (encompasses[0] != sp->get_bound (LEFT))
+    {
+      offsets.top ()[Y_AXIS] -= encompasses.top ()->relative_coordinate (common[Y_AXIS], Y_AXIS) 
+	- me->relative_coordinate (common[Y_AXIS], Y_AXIS);
+    }
 
-  return offset_arr;
+  return offsets;
 }
 
 
-Array<Rod>
-Slur::get_rods () const
+
+
+/*
+  ugh ?
+ */
+MAKE_SCHEME_CALLBACK (Slur, height, 2);
+SCM
+Slur::height (SCM smob, SCM ax)
 {
-  Array<Rod> a;
-  Rod r;
-  
-  r.item_l_drul_[LEFT] = get_bound (LEFT);
-  r.item_l_drul_[RIGHT] = get_bound (RIGHT);
-  r.distance_f_ = paper_l ()->get_var ("slur_x_minimum");
+  Axis a = (Axis)gh_scm2int (ax);
+  Grob * me = unsmob_grob (smob);
+  assert (a == Y_AXIS);
 
-  a.push (r);
-  return a;
+  SCM mol = me->get_uncached_molecule ();
+  return ly_interval2scm (unsmob_molecule (mol)->extent (a));
 }
 
-
 /*
   Ugh should have dash-length + dash-period
  */
-GLUE_SCORE_ELEMENT(Slur,brew_molecule);
+MAKE_SCHEME_CALLBACK (Slur, brew_molecule,1);
 SCM
-Slur::member_brew_molecule () const
+Slur::brew_molecule (SCM smob)
 {
-  Real thick = paper_l ()->get_var ("slur_thickness");
-  Bezier one = get_curve ();
+  Grob * me = unsmob_grob (smob);
+  if (!scm_ilength (me->get_grob_property ("note-columns")))
+    {
+      me->suicide ();
+      return SCM_EOL;
+    }
+
+  Real thick = me->get_paper ()->get_var ("linethickness") *
+    gh_scm2double (me->get_grob_property ("thickness"));
+  Bezier one = get_curve (me);
+
+  // get_curve may suicide
+  if (!scm_ilength (me->get_grob_property ("note-columns")))
+    return SCM_EOL;
 
   Molecule a;
-  SCM d =  get_elt_property ("dashed");
+  SCM d =  me->get_grob_property ("dashed");
   if (gh_number_p (d))
-    a = lookup_l ()->dashed_slur (one, thick, thick * gh_scm2double (d));
+    a = Lookup::dashed_slur (one, thick, thick * gh_scm2double (d));
   else
-    a = lookup_l ()->slur (one, directional_element (this).get () * thick, thick);
+    a = Lookup::slur (one, Directional_element_interface::get (me) * thick, thick);
 
-  return a.create_scheme();
+  return a.smobbed_copy ();
 }
 
 void
-Slur::set_control_points ()
+Slur::set_control_points (Grob*me)
 {
-  Slur_bezier_bow bb (get_encompass_offset_arr (),
-		      directional_element (this).get ());
+  Real staff_space = Staff_symbol_referencer::staff_space ((Grob*)me);
+
+  SCM details = me->get_grob_property ("details");
+  SCM h_inf_scm = me->get_grob_property ("height-limit");
+  SCM r_0_scm = me->get_grob_property ("ratio");
 
-  Real staff_space = Staff_symbol_referencer_interface (this).staff_space ();
-  Real h_inf = paper_l ()->get_var ("slur_height_limit_factor") * staff_space;
-  Real r_0 = paper_l ()->get_var ("slur_ratio");
+  Real r_0 = gh_scm2double (r_0_scm);
+  Real h_inf = staff_space * gh_scm2double (h_inf_scm);
+  
+  Slur_bezier_bow bb (get_encompass_offsets (me),
+		      Directional_element_interface::get (me),
+		      h_inf, r_0);
 
-  bb.set_default_bezier (h_inf, r_0);
 
   if (bb.fit_factor () > 1.0)
     {
       Real length = bb.curve_.control_[3][X_AXIS]; 
-      Real default_height = bb.get_default_height (h_inf, r_0, length);
-      bb.minimise_enclosed_area (paper_l(), default_height);
-      
-      Real bff = paper_l ()->get_var ("slur_force_blowfit");
+      Real default_height = slur_height (length, h_inf, r_0);
+
+      SCM ssb = me->get_grob_property ("beautiful");
+      Real sb = 0;
+      if (gh_number_p (ssb))
+	sb = gh_scm2double (ssb);
+
+      bb.minimise_enclosed_area (sb, details);
+      SCM sbf = scm_assq (ly_symbol2scm ("force-blowfit"), details);
+      Real bff = 1.0;
+      if (gh_pair_p (sbf) && gh_number_p (ly_cdr (sbf)))
+	  bff = gh_scm2double (ly_cdr (sbf));
+
       bb.curve_.control_[1][Y_AXIS] *= bff;
       bb.curve_.control_[2][Y_AXIS] *= bff;
       bb.blow_fit ();
 
-      Real sb = paper_l ()->get_var ("slur_beautiful");
+      
       Real beautiful = length * default_height * sb;
-      Real area = bb.enclosed_area_f ();
+      Real area = bb.get_enclosed_area ();
       
       /*
 	Slurs that fit beautifully are not ugly
       */
       if (area > beautiful)
-	de_uglyfy (&bb, default_height);
+	de_uglyfy (me, &bb, default_height);
     }
 
   Bezier b = bb.get_bezier ();
@@ -440,37 +621,57 @@ Slur::set_control_points ()
 
   SCM controls = SCM_EOL;
   for (int i= 4; i--;)
-    controls = gh_cons ( ly_offset2scm (b.control_[i]), controls);
+    {
+      controls = gh_cons (ly_offset2scm (b.control_[i]), controls);
+      /*
+	BRRR WHURG.
+	All these null control-points, where do they all come from?
+      */
+      if (i && b.control_[i][X_AXIS] == 0)
+	{
+	  me->suicide ();
+	  return;
+	}
+    }
 
-  set_elt_property ("control-points", controls);
+  me->set_grob_property ("control-points", controls);
 }
   
-  
 Bezier
-Slur::get_curve () const
+Slur::get_curve (Grob*me) 
 {
   Bezier b;
   int i = 0;
 
-  if (!directional_element (this).get ())
-    ((Slur*)this)->set_extremities ();
-  
-  if (!gh_pair_p (get_elt_property ("control-points")))
-    ((Slur*)this)->set_control_points ();
+  SCM attach = me->get_grob_property ("attachment");
+  if (!gh_pair_p (attach))
+    attach = set_extremities(me);
+
   
+  if (!Directional_element_interface::get (me)
+      || ! gh_symbol_p (index_get_cell (attach, LEFT))
+      || ! gh_symbol_p (index_get_cell (attach, RIGHT)))
+    set_extremities (me);
   
-  for (SCM s= get_elt_property ("control-points"); s != SCM_EOL; s = gh_cdr (s))
+  if (!gh_pair_p (me->get_grob_property ("control-points")))
+    set_control_points (me);
+
+  // set_control_points may suicide
+  if (!scm_ilength (me->get_grob_property ("note-columns")))
+    return b;
+
+  for (SCM s= me->get_grob_property ("control-points"); s != SCM_EOL; s = ly_cdr (s))
     {
-      b.control_[i] = ly_scm2offset (gh_car (s));
+      b.control_[i] = ly_scm2offset (ly_car (s));
       i++;
     }
-  
-  Array<Offset> enc (get_encompass_offset_arr ());
-  Direction dir = directional_element (this).get ();
+
+  Array<Offset> enc (get_encompass_offsets (me));
+  Direction dir = Directional_element_interface::get (me);
   
   Real x1 = enc[0][X_AXIS];
   Real x2 = enc.top ()[X_AXIS];
-  
+
   Real off = 0.0;
   for (int i=1; i < enc.size ()-1; i++)
     {
@@ -478,10 +679,17 @@ Slur::get_curve () const
       if (x > x1 && x <x2)
 	{
 	  Real y = b.get_other_coordinate (X_AXIS, x);
-	  off = off >? dir *  (enc[i][Y_AXIS] - y);
+	  off = off >? dir * (enc[i][Y_AXIS] - y);
 	}
     }
   b.translate (Offset (0, dir * off));
   return b;
 }
 
+
+
+
+ADD_INTERFACE (Slur,"slur-interface",
+  "A slur",
+  "attachment attachment-offset beautiful control-points dashed details de-uglify-parameters direction extremity-rules extremity-offset-alist height-limit ratio slope-limit thickness y-free");
+