lily/separating-group-spanner.cc

   1 /*
   2   separating-group-spanner.cc --  implement Separating_group_spanner
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1998--2003 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7
   8  */
   9
  10 #include "separating-group-spanner.hh"
  11 #include "separation-item.hh"
  12 #include "paper-column.hh"
  13 #include "paper-def.hh"
  14 #include "dimensions.hh"
  15 #include "group-interface.hh"
  16
  17 void
  18 Separating_group_spanner::find_rods (Item * r, SCM next)
  19 {
  20
  21   /*
  22     This is an inner loop: look for the first normal (unbroken) Left
  23     grob.  This looks like an inner loop (ie. quadratic total), but in
  24     most cases, the interesting L will just be the first entry of
  25     NEXT, making it linear in most of the cases.
  26   */
  27   if (Separation_item::width (r).empty_b ())
  28     return;
  29
  30   for(; gh_pair_p (next); next = ly_cdr (next))
  31     {
  32       Item *l = dynamic_cast<Item*> (unsmob_grob (ly_car( next)));
  33       Item *lb = l->find_prebroken_piece (RIGHT);
  34
  35       if (lb)
  36         {
  37           Interval li (Separation_item::width (lb));
  38           Interval ri (Separation_item::conditional_width (r, lb));
  39           if (!li.empty_b () && !ri.empty_b())
  40             {
  41               Rod rod;
  42
  43               rod.item_l_drul_[LEFT] = lb;
  44               rod.item_l_drul_[RIGHT] = r;
  45
  46               rod.distance_ = li[RIGHT] - ri[LEFT];
  47               rod.add_to_cols ();
  48             }
  49         }
  50
  51       Interval li (Separation_item::width (l));
  52       Interval ri (Separation_item::conditional_width (r, l));
  53       if (!li.empty_b () && !ri.empty_b())
  54         {
  55           Rod rod;
  56
  57           rod.item_l_drul_[LEFT] =l;
  58           rod.item_l_drul_[RIGHT]=r;
  59
  60           rod.distance_ = li[RIGHT] - ri[LEFT];
  61
  62           rod.add_to_cols ();
  63           break;
  64         }
  65
  66       /*
  67         this grob doesn't cause a constraint. We look further until we
  68         find one that does.
  69       */
  70
  71     }
  72 }
  73
  74 MAKE_SCHEME_CALLBACK (Separating_group_spanner,set_spacing_rods_and_seqs,1);
  75 SCM
  76 Separating_group_spanner::set_spacing_rods_and_seqs (SCM smob)
  77 {
  78   set_spacing_rods (smob);
  79
  80   return SCM_UNSPECIFIED;
  81 }
  82
  83 MAKE_SCHEME_CALLBACK (Separating_group_spanner,set_spacing_rods,1);
  84 SCM
  85 Separating_group_spanner::set_spacing_rods (SCM smob)
  86 {
  87   Grob*me = unsmob_grob (smob);
  88
  89   for (SCM s = me->get_grob_property ("elements"); gh_pair_p (s) && gh_pair_p (ly_cdr (s)); s = ly_cdr (s))
  90     {
  91       /*
  92         Order of elements is reversed!
  93        */
  94       SCM elt = ly_car (s);
  95       Item *r = unsmob_item (elt);
  96
  97       if (!r)
  98         continue;
  99
 100       Item *rb
 101         = dynamic_cast<Item*> (r->find_prebroken_piece (LEFT));
 102
 103       find_rods (r, ly_cdr (s));
 104       if (rb)
 105         find_rods (rb, ly_cdr (s));
 106     }
 107
 108   return SCM_UNSPECIFIED ;
 109 }
 110
 111 void
 112 Separating_group_spanner::add_spacing_unit (Grob* me ,Item*i)
 113 {
 114   Pointer_group_interface::add_grob (me, ly_symbol2scm ("elements"), i);
 115   me->add_dependency (i);
 116 }
 117
 118
 119
 120
 121
 122 ADD_INTERFACE (Separating_group_spanner,"separation-spanner-interface",
 123   "Spanner that containing @code{separation-item-interface} grobs to calculate rods",
 124   "");