lily/tie-column.cc

   1 /*
   2   tie-column.cc --  implement Tie_column
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2000--2001 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7
   8  */
   9
  10 #include "spanner.hh"
  11 #include "tie-column.hh"
  12 #include "group-interface.hh"
  13 #include "tie.hh"
  14 #include "directional-element-interface.hh"
  15 #include "rhythmic-head.hh"
  16
  17
  18
  19 void
  20 Tie_column::set_interface (Grob*me)
  21 {
  22   me->set_interface (ly_symbol2scm ("tie-column-interface"));
  23   me->set_extent_callback (SCM_EOL, X_AXIS);
  24   me->set_extent_callback (SCM_EOL, Y_AXIS) ;
  25 }
  26
  27 bool
  28 Tie_column::has_interface (Grob*me)
  29 {
  30   return  me->has_interface (ly_symbol2scm ("tie-column-interface"));
  31 }
  32
  33
  34 /*
  35   tie dir depends on what Tie_column does.
  36 */
  37
  38 void
  39 Tie_column::add_tie (Grob*me,Grob *s)
  40 {
  41   if (!  Pointer_group_interface ::count (me, "ties"))
  42     {
  43       dynamic_cast<Spanner*> (me)->set_bound (LEFT, Tie::head (s,LEFT));
  44       dynamic_cast<Spanner*> (me)->set_bound (RIGHT, Tie::head (s,RIGHT));
  45     }
  46
  47   Pointer_group_interface::add_element (me, "ties",s);
  48   s->add_dependency (me);
  49 }
  50
  51
  52 int
  53 tie_compare (Grob* const & s1,
  54              Grob* const & s2)
  55 {
  56   return sign (Tie::position_f (s1) - Tie::position_f (s2));
  57 }
  58
  59 /*
  60   See [Ross p. 138].
  61
  62
  63   In normal chord cases, the outer ties point outwards, and the
  64   direction of the rest is determined by their staff position.
  65
  66   Ross forgets about the tie that is *on* the middle staff line. We
  67   assume it goes UP. (TODO: make me settable) */
  68 void
  69 Tie_column::set_directions (Grob*me)
  70 {
  71   Link_array<Grob> ties =
  72     Pointer_group_interface__extract_elements (me, (Grob*)0, "ties");
  73
  74   for (int i = ties.size (); i--;)
  75     if (Directional_element_interface::get (ties[i]))
  76       ties.del (i);
  77
  78
  79   if (!ties.size ())
  80     return ;
  81
  82
  83   Direction d = Directional_element_interface::get (me);
  84   if (d)
  85     {
  86       for (int i = ties.size (); i--;)
  87         {
  88           Grob *  t = ties[i];
  89           Directional_element_interface::set (t, d);
  90         }
  91       return;
  92     }
  93
  94   if (ties.size () == 1)
  95     {
  96       Grob *  t = ties[0];
  97       Directional_element_interface::set (t,Tie::get_default_dir (t));
  98       return;
  99     }
 100
 101   ties.sort (tie_compare);
 102   Directional_element_interface::set (ties[0], DOWN);
 103   ties.del (0);
 104
 105   Directional_element_interface ::set (ties.pop (), UP);
 106   for (int i=ties.size (); i--;)
 107     {
 108       Grob *  t = ties[i];
 109       Real p = Tie::position_f (t);
 110       Direction d = (Direction) sign (p);
 111       if (!d)
 112         d = UP;
 113       Directional_element_interface::set (t, d);
 114     }
 115
 116 }
 117
 118 MAKE_SCHEME_CALLBACK (Tie_column,after_line_breaking,1);
 119 SCM
 120 Tie_column::after_line_breaking (SCM smob)
 121 {
 122   set_directions (unsmob_grob (smob));
 123   return SCM_UNSPECIFIED;
 124 }