path: root/lily/slur.cc

/*
  slur.cc -- implement  Slur

  source file of the GNU LilyPond music typesetter

  (c) 1996,  1997--1998, 1998 Han-Wen Nienhuys <hanwen@cs.uu.nl>
    Jan Nieuwenhuizen <janneke@gnu.org>
*/

/*
  [TODO]
    * URG: share code with tie
    * begin and end should be treated as a Script.
    * damping
    * slur from notehead to stemend: c''()b''
 */

#include "slur.hh"
#include "scalar.hh"
#include "lookup.hh"
#include "paper-def.hh"
#include "note-column.hh"
#include "stem.hh"
#include "p-col.hh"
#include "molecule.hh"
#include "debug.hh"
#include "box.hh"
#include "bezier.hh"
#include "encompass-info.hh"
#include "main.hh"


Slur::Slur ()
{
}

void
Slur::add_column (Note_column*n)
{
  if (!n->head_l_arr_.size ())
    warning (_ ("Putting slur over rest."));
  encompass_arr_.push (n);
  n->stem_l_->slur_l_ = this;
  add_dependency (n);
}

void
Slur::set_default_dir ()
{
  dir_ = DOWN;
  for (int i=0; i < encompass_arr_.size (); i ++) 
    {
      if (encompass_arr_[i]->dir_ < 0) 
	{
	  dir_ = UP;
	  break;
	}
    }
}

void
Slur::do_add_processing ()
{
  set_bounds (LEFT, encompass_arr_[0]);    
  if (encompass_arr_.size () > 1)
    set_bounds (RIGHT, encompass_arr_.top ());
}

void
Slur::do_pre_processing ()
{
  // don't set directions
}

void
Slur::do_substitute_dependency (Score_element*o, Score_element*n)
{
  int i;
  while ((i = encompass_arr_.find_i (dynamic_cast<Note_column *> (o))) >=0) 
    {
      if (n)
	encompass_arr_[i] = dynamic_cast<Note_column *> (n);
      else
	encompass_arr_.del (i);
    }
}

static int 
Note_column_compare (Note_column *const&n1 , Note_column* const&n2)
{
  return Item::left_right_compare (n1, n2);
}

void
Slur::do_post_processing ()
{
  encompass_arr_.sort (Note_column_compare);
  if (!dir_)
    set_default_dir ();

  Real interline_f = paper ()->interline_f ();
  Real internote_f = interline_f / 2;
  // URG
  Real notewidth_f = paper ()->note_width () * 0.8;

  /* 
   [OSU]: slur and tie placement

   slurs:
   * x = centre of head (upside-down: inner raakpunt stem) - d * gap

   * y = length < 5ss : horizontal raakpunt + d * 0.25 ss
     y = length >= 5ss : y next interline - d * 0.25 ss
     --> height <= 5 length ?? we use <= 3 length, now...
   */
  
  Real gap_f = paper ()->get_var ("slur_x_gap");

  Drul_array<Note_column*> extrema;
  extrema[LEFT] = encompass_arr_[0];
  extrema[RIGHT] = encompass_arr_.top ();

  Direction d=LEFT;
 
  do 
    {
      /*
        broken slur
       */
      if (extrema[d] != spanned_drul_[d]) 
	{
	  // ugh -- check if needed
	  dx_f_drul_[d] = -d 
	    *(spanned_drul_[d]->extent (X_AXIS).length () - 0.5 * notewidth_f);

	  // prebreak
	  if (d == RIGHT)
	    {
	      dx_f_drul_[LEFT] = spanned_drul_[LEFT]->extent (X_AXIS).length ();

	      // urg -- check if needed
	      if (encompass_arr_.size () > 1)
		dx_f_drul_[RIGHT] += notewidth_f;
	    }
	}
      /*
        normal slur
       */
      else if (extrema[d]->stem_l_ && !extrema[d]->stem_l_->transparent_b_ 
	       && extrema[d]->head_l_arr_.size ()) 
        {
	  Real notewidth_f = extrema[d]->extent (X_AXIS).length ();
	  dy_f_drul_[d] = (int)rint (extrema[d]->stem_l_-> extent (Y_AXIS)[dir_]);
	  dx_f_drul_[d] += 0.5 * notewidth_f - d * gap_f;
	  if (dir_ == extrema[d]->stem_l_->dir_)
	    {
	      if (dir_ == d)
		dx_f_drul_[d] += 0.5 * (dir_ * d) * d * notewidth_f;
	      else
		dx_f_drul_[d] += 0.25 * (dir_ * d) * d * notewidth_f;
	    }
	}
	else 
	  {
	    Real notewidth_f = extrema[d]->extent (X_AXIS).length ();
	    dy_f_drul_[d] = (int)rint (extrema[d]->head_positions_interval ()
				       [dir_]) * internote_f;
	    dx_f_drul_[d] += 0.5 * notewidth_f - d * gap_f;
	}
	dy_f_drul_[d] += dir_ * interline_f;
	if (extrema[d]->stem_l_ && (dir_ == extrema[d]->stem_l_->dir_))
	  dy_f_drul_[d] -= dir_ * internote_f;
      }
  while (flip(&d) != LEFT);

  // now that both are set, do dependent
  do 
    {
      /*
        broken slur
       */
      if (extrema[d] != spanned_drul_[d]) 
        {
	  Direction u = d;
	  flip(&u);

	  // postbreak
	  if (d == LEFT)
	    dy_f_drul_[u] += dir_ * internote_f;

	  dy_f_drul_[d] = dy_f_drul_[(Direction)-d];
	}
     }
  while (flip(&d) != LEFT);

  /*
    Avoid too steep slurs.
      * slur from notehead to stemend: c''()b''
   */
  Real damp_f = paper ()->get_var ("slur_slope_damping");
  Offset d_off = Offset (dx_f_drul_[RIGHT] - dx_f_drul_[LEFT],
    dy_f_drul_[RIGHT] - dy_f_drul_[LEFT]);
  d_off.x () += extent (X_AXIS).length ();

  Real ratio_f = abs (d_off.y () / d_off.x ());
  if (ratio_f > damp_f)
    dy_f_drul_[(Direction)(- dir_ * sign (d_off.y ()))] +=
      dir_ * (ratio_f - damp_f) * d_off.x ();
}

Array<Offset>
Slur::get_encompass_offset_arr () const
{
  Real notewidth = paper ()->note_width () * 0.8;
  Real gap = paper ()->get_var ("slur_x_gap");
  Real internote = paper ()->internote_f ();

  Offset left = Offset (dx_f_drul_[LEFT], dy_f_drul_[LEFT]);
  left.x () += encompass_arr_[0]->stem_l_->hpos_f ();

  /*
    <URG>
    i don't understand these two, but *must* for symmetry 
    look at encompass array: 
       lilypond -D input/test/slur-symmetry*.ly
       lilypond -D input/test/sleur.ly

    do_post_processing should have calculated these into
    dx_f_drul_[], no??

   */

  if (dir_ != encompass_arr_[0]->stem_l_->dir_)
    left.x () += - 0.5 * notewidth * encompass_arr_[0]->stem_l_->dir_
      + gap;
  else if (encompass_arr_[0]->stem_l_->dir_ == UP)
    left.x () -= notewidth;

  if ((dir_ == encompass_arr_[0]->stem_l_->dir_) 
    && (encompass_arr_[0]->stem_l_->dir_ == DOWN))
    left.y () -= internote * encompass_arr_[0]->stem_l_->dir_;
  /* </URG> */

  Offset d = Offset (dx_f_drul_[RIGHT] - dx_f_drul_[LEFT],
    dy_f_drul_[RIGHT] - dy_f_drul_[LEFT]);
  d.x () += extent (X_AXIS).length ();

  int first = 1;
  int last = encompass_arr_.size () - 1;

  // prebreak
  if (encompass_arr_.top () != spanned_drul_[RIGHT])
    last++;

  // postbreak
  if (encompass_arr_[0] != spanned_drul_[LEFT])
    first--;

  Array<Offset> notes;
  notes.push (Offset (0,0));

  for (int i = first; i < last; i++)
    {
      Encompass_info info (encompass_arr_[i], dir_);
      notes.push (info.o_ - left);
    }
  Encompass_info info (encompass_arr_[encompass_arr_.size () - 1], dir_);
  // urg:
  Slur* urg = (Slur*)this;
  urg->interstaff_f_ = info.interstaff_f_;
  d.y () += interstaff_f_;

  // prebreak
  if (interstaff_f_ && (encompass_arr_.top () != spanned_drul_[RIGHT]))
    {
      Encompass_info info (encompass_arr_[encompass_arr_.size () - 1], dir_);
      d.y () -= info.o_.y () - interstaff_f_;
    }

  notes.push (d);

  return notes;
}

Interval
Slur::do_width () const
{
  Real min_f = paper ()->get_var ("slur_x_minimum");
  Interval width_int = Bow::do_width ();
  return width_int.length () < min_f ? Interval (0, min_f) : width_int;
}

Array<Rod>
Slur::get_rods () const
{
  Array<Rod> a;
  Rod r;
  r.item_l_drul_ = spanned_drul_;
  r.distance_f_ = do_width ().length ();
  a.push (r);
  return a;
}