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--2002 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
  20
  21
  22 /*
  23   tie dir depends on what Tie_column does.
  24 */
  25
  26 void
  27 Tie_column::add_tie (Grob*me,Grob *s)
  28 {
  29   if (!  Pointer_group_interface ::count (me, "ties"))
  30     {
  31       dynamic_cast<Spanner*> (me)->set_bound (LEFT, Tie::head (s,LEFT));
  32       dynamic_cast<Spanner*> (me)->set_bound (RIGHT, Tie::head (s,RIGHT));
  33     }
  34
  35   Pointer_group_interface::add_grob (me, ly_symbol2scm ("ties"), s);
  36   s->add_dependency (me);
  37 }
  38
  39
  40 int
  41 tie_compare (Grob* const & s1,
  42              Grob* const & s2)
  43 {
  44   return sign (Tie::get_position (s1) - Tie::get_position (s2));
  45 }
  46
  47 /*
  48   See [Ross p. 138].
  49
  50
  51   In normal chord cases, the outer ties point outwards, and the
  52   direction of the rest is determined by their staff position.
  53
  54   Ross forgets about the tie that is *on* the middle staff line. We
  55   assume it goes UP. (TODO: make me settable) */
  56 void
  57 Tie_column::set_directions (Grob*me)
  58 {
  59   Link_array<Grob> ties =
  60     Pointer_group_interface__extract_grobs (me, (Grob*)0, "ties");
  61
  62   for (int i = ties.size (); i--;)
  63     if (Directional_element_interface::get (ties[i]))
  64       ties.del (i);
  65
  66
  67   if (!ties.size ())
  68     return ;
  69
  70
  71   Direction d = Directional_element_interface::get (me);
  72   if (d)
  73     {
  74       for (int i = ties.size (); i--;)
  75         {
  76           Grob *  t = ties[i];
  77           Directional_element_interface::set (t, d);
  78         }
  79       return;
  80     }
  81
  82   if (ties.size () == 1)
  83     {
  84       Grob *  t = ties[0];
  85       Directional_element_interface::set (t,Tie::get_default_dir (t));
  86       return;
  87     }
  88
  89   ties.sort (tie_compare);
  90   Directional_element_interface::set (ties[0], DOWN);
  91   ties.del (0);
  92
  93   Directional_element_interface ::set (ties.pop (), UP);
  94   for (int i=ties.size (); i--;)
  95     {
  96       Grob *  t = ties[i];
  97       Real p = Tie::get_position (t);
  98       Direction d = (Direction) sign (p);
  99       if (!d)
 100         d = UP;
 101       Directional_element_interface::set (t, d);
 102     }
 103
 104 }
 105
 106 MAKE_SCHEME_CALLBACK (Tie_column,after_line_breaking,1);
 107 SCM
 108 Tie_column::after_line_breaking (SCM smob)
 109 {
 110   set_directions (unsmob_grob (smob));
 111   return SCM_UNSPECIFIED;
 112 }
 113
 114
 115
 116 ADD_INTERFACE (Tie_column,"tie-column-interface",
 117   "that sets tie directions in a tied chord",
 118   "direction");
 119