lily/slur.cc

   1 /*
   2   slur.cc -- implement  Slur
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1996, 1997 Han-Wen Nienhuys <hanwen@stack.nl>
   7 */
   8
   9 /*
  10   TODO:
  11
  12   think about crossing stems.
  13   Begin and end should be treated as a Script.
  14  */
  15 #include "slur.hh"
  16 #include "scalar.hh"
  17 #include "lookup.hh"
  18 #include "paper-def.hh"
  19 #include "note-column.hh"
  20 #include "stem.hh"
  21 #include "p-col.hh"
  22 #include "molecule.hh"
  23 #include "debug.hh"
  24 #include "boxes.hh"
  25
  26 void
  27 Slur::add (Note_column*n)
  28 {
  29   encompass_arr_.push (n);
  30   add_dependency (n);
  31 }
  32
  33 void
  34 Slur::set_default_dir ()
  35 {
  36   dir_ = DOWN;
  37   for (int i=0; i < encompass_arr_.size (); i ++)
  38     {
  39       if (encompass_arr_[i]->dir_ < 0)
  40         {
  41           dir_ = UP;
  42           break;
  43         }
  44     }
  45 }
  46
  47 void
  48 Slur::do_add_processing ()
  49 {
  50   set_bounds (LEFT, encompass_arr_[0]);
  51   if (encompass_arr_.size () > 1)
  52     set_bounds (RIGHT, encompass_arr_.top ());
  53 }
  54
  55 void
  56 Slur::do_pre_processing ()
  57 {
  58   // don't set directions
  59 }
  60
  61 void
  62 Slur::do_substitute_dependency (Score_elem*o, Score_elem*n)
  63 {
  64   int i;
  65   while ((i = encompass_arr_.find_i ((Note_column*)o->item ())) >=0)
  66     {
  67       if (n)
  68         encompass_arr_[i] = (Note_column*)n->item ();
  69       else
  70         encompass_arr_.del (i);
  71     }
  72 }
  73
  74 static int
  75 Note_column_compare (Note_column *const&n1 , Note_column* const&n2)
  76 {
  77   return Item::left_right_compare (n1, n2);
  78 }
  79
  80 void
  81 Slur::do_post_processing ()
  82 {
  83   encompass_arr_.sort (Note_column_compare);
  84   if (!dir_)
  85     set_default_dir ();
  86   Real interline_f = paper ()->interline_f ();
  87   Real inter_f = interline_f / 2;
  88
  89   /*
  90    [OSU]: slur and tie placement
  91
  92    slurs:
  93    * x = centre of head (upside-down: inner raakpunt stem) - d * gap
  94
  95    * y = length < 5ss : horizontal raakpunt + d * 0.25 ss
  96      y = length >= 5ss : y next interline - d * 0.25 ss
  97      --> height <= 5 length ?? we use <= 3 length, now...
  98
  99    * suggested gap = ss / 5;
 100    */
 101   // jcn: 1/5 seems so small?
 102   Real gap_f = interline_f / 2; // 5;
 103
 104   Drul_array<Note_column*> extrema;
 105   extrema[LEFT] = encompass_arr_[0];
 106   extrema[RIGHT] = encompass_arr_.top ();
 107
 108   Direction d=LEFT;
 109   Real nw_f = paper ()->note_width ();
 110
 111   do
 112     {
 113       if  (extrema[d] != spanned_drul_[d])
 114         {
 115           dx_f_drul_[d] = -d
 116             *(spanned_drul_[d]->width ().length () -0.5*nw_f);
 117         }
 118       else if (extrema[d]->stem_l_ && !extrema[d]->stem_l_->transparent_b_)
 119         {
 120           dy_f_drul_[d] = (int)rint (extrema[d]->stem_l_->height ()[dir_]);
 121           /* normal slur from notehead centre to notehead centre, minus gap */
 122           dx_f_drul_[d] += -d * gap_f;
 123         }
 124       else
 125         {
 126           dy_f_drul_[d] = (int)rint (extrema[d]->head_positions_interval ()[dir_])* inter_f;
 127         }
 128       dy_f_drul_[d] += dir_ * interline_f;
 129     }
 130   while ((d *= -1) != LEFT);
 131 }
 132
 133 Real
 134 Slur::height_f () const
 135 {
 136   /*
 137    rather braindead way that of adjusting slur height
 138    for heads/stems that extend beyond default slur
 139    works quite good
 140    */
 141
 142   Real interline_f = paper ()->interline_f ();
 143   Real nh_f = interline_f / 2;
 144   Real h = 0;
 145   Real dx = width ().length ();
 146   Real dy = dy_f_drul_[RIGHT] - dy_f_drul_[LEFT];
 147   Stem* stem = encompass_arr_[0]->stem_l_;
 148   Real lx = stem->hpos_f ();
 149   Real centre = (width ().min () + width ().max ()) / 2;
 150   Real ly = stem->dir_ == dir_ ? stem->stem_end_f () : stem->stem_begin_f ()
 151     + dir_ * nh_f / 2;
 152   for (int i = 0; i < encompass_arr_.size (); i++)
 153     {
 154       Stem* stem = encompass_arr_[i]->stem_l_;
 155       Real sx = abs (centre - stem->hpos_f ());
 156       Real sy = stem->dir_ == dir_ ? stem->stem_end_f ()
 157         : stem->stem_begin_f () + dir_ * nh_f / 2;
 158       sy = dir_ * (sy - (ly + ((stem->hpos_f () - lx) / dx) * dy));
 159       /*
 160         uhm, correct for guess bezier curve (more if further from centre)
 161         forget the cos alpha...
 162        */
 163       if (sy > 0)
 164         h = h >? sy * (1 + 2 * sx / dx);
 165     }
 166   Real ratio = 1.0/3; // duh
 167   /*
 168     correct h for slur ratio
 169    */
 170   Real staffheight = paper ()->get_var ("barsize");
 171   if (h)
 172     h *= ((h * interline_f) / dx ) / ratio;
 173   return h;
 174 }
 175
 176 IMPLEMENT_IS_TYPE_B1(Slur,Spanner);