lily/dot-column.cc

   1 /*
   2   dot-column.cc -- implement Dot_column
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--2001 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9 #include "dots.hh"
  10 #include "dot-column.hh"
  11 #include "rhythmic-head.hh"
  12 #include "group-interface.hh"
  13 #include "staff-symbol-referencer.hh"
  14 #include "directional-element-interface.hh"
  15 #include "side-position-interface.hh"
  16 #include "axis-group-interface.hh"
  17 #include "stem.hh"
  18
  19 void
  20 Dot_column::set_interface (Grob* me)
  21 {
  22 }
  23 MAKE_SCHEME_CALLBACK (Dot_column,force_shift_callback,2);
  24 SCM
  25 Dot_column::force_shift_callback (SCM element_smob, SCM axis)
  26 {
  27   Grob *me = unsmob_grob (element_smob);
  28   Axis a = (Axis) gh_scm2int (axis);
  29   assert (a == Y_AXIS);
  30   me = me->parent_l (X_AXIS);
  31   SCM l = me->get_grob_property ("dots");
  32   do_shifts (l);
  33   return gh_double2scm (0.0);
  34 }
  35
  36 MAKE_SCHEME_CALLBACK(Dot_column,side_position, 2);
  37 SCM
  38 Dot_column::side_position (SCM element_smob, SCM axis)
  39 {
  40   Grob *me = unsmob_grob (element_smob);
  41   Axis a = (Axis) gh_scm2int (axis);
  42   assert (a == X_AXIS);
  43
  44   Grob * stem = unsmob_grob (me->get_grob_property ("stem"));
  45   if (stem
  46       && !Stem::beam_l (stem)
  47       && Stem::flag_i (stem))
  48     {
  49       /*
  50         trigger stem end & direction calculation.
  51
  52         This will add the stem to the support if a flag collision happens.
  53        */
  54       Stem::stem_end_position (stem);
  55     }
  56   return Side_position_interface::aligned_side (element_smob, axis);
  57 }
  58
  59
  60 /*
  61   Will fuck up in this case.
  62
  63   X.  .
  64   X.X .
  65    |X .
  66    |
  67    |
  68    |X .
  69    |
  70    |
  71
  72
  73    Should be smarter.
  74  */
  75 SCM
  76 Dot_column::do_shifts (SCM l)
  77 {
  78   Link_array<Grob> dots;
  79   while (gh_pair_p (l))
  80     {
  81       dots.push (unsmob_grob (gh_car (l)));
  82       l = gh_cdr (l);
  83     }
  84
  85   dots.sort (compare_position);
  86
  87   if (dots.size () < 2)
  88     return SCM_UNSPECIFIED;
  89   Slice s;
  90   s.set_empty ();
  91
  92   Array<int> taken_posns;
  93   int conflicts = 0;
  94   for (int i=0; i < dots.size (); i++)
  95     {
  96       Real p = Staff_symbol_referencer::position_f (dots[i]);
  97       for (int j=0; j < taken_posns.size (); j++)
  98         {
  99           if (taken_posns[j] == (int) p)
 100             conflicts++;
 101         }
 102       taken_posns.push ((int)p);
 103       s.unite (Slice ((int)p,
 104  (int)p));
 105     }
 106
 107   if (!conflicts)
 108     return SCM_UNSPECIFIED;
 109
 110   int  middle = s.center ();
 111   /*
 112     +1 -> off by one
 113    */
 114   int pos = middle - dots.size () + 1;
 115   if (! (pos % 2))
 116     pos ++;                     // center () rounds down.
 117
 118   for (int i=0; i < dots.size (); pos += 2, i++)
 119     {
 120       Grob * d = dots[i];
 121       Staff_symbol_referencer::set_position (d,pos);
 122     }
 123
 124   return SCM_UNSPECIFIED;
 125 }
 126
 127 bool
 128 Dot_column::has_interface (Grob*m)
 129 {
 130   return m && m->has_interface (ly_symbol2scm ("dot-column-interface"));
 131 }
 132
 133
 134 void
 135 Dot_column::add_head (Grob * me, Grob *rh)
 136 {
 137   Grob * d = unsmob_grob (rh->get_grob_property ("dot"));
 138   if (d)
 139     {
 140       Side_position_interface::add_support (me,rh);
 141
 142       Pointer_group_interface ::add_element (me, "dots",d);
 143       d->add_offset_callback (Dot_column::force_shift_callback_proc , Y_AXIS);
 144       Axis_group_interface::add_element (me, d);
 145     }
 146 }
 147