* lexer-gcc-3.1.sh: Remove.

[lilypond/patrick.git] / lily / tie-formatting-problem.cc

/*
  tie-formatting-problem.cc -- implement Tie_formatting_problem

  source file of the GNU LilyPond music typesetter

  (c) 2005--2006 Han-Wen Nienhuys <hanwen@xs4all.nl>

*/

#include "tie-formatting-problem.hh"

#include "paper-column.hh"
#include "bezier.hh" 
#include "directional-element-interface.hh"
#include "item.hh"
#include "libc-extension.hh"
#include "misc.hh"
#include "note-head.hh"
#include "rhythmic-head.hh"
#include "spanner.hh" 
#include "staff-symbol-referencer.hh"
#include "stem.hh"
#include "tie-configuration.hh"
#include "tie.hh"
#include "warn.hh"


void
Tie_formatting_problem::print_ties_configuration (Ties_configuration const *ties)
{
  for (vsize i = 0; i < ties->size (); i++)
    {
      char const *man_pos = (specifications_[i].has_manual_position_) ? "(M)" : "";
      char const *man_dir = (specifications_[i].has_manual_dir_) ? "(M)" : "";
      char const *dir = (ties->at (i).dir_ == UP) ? "up" : "dn";
      
      printf ("(P%d%s, %s%s) ", ties->at (i).position_, man_pos, dir, man_dir);
    }
  printf ("\n");
}

Interval
Tie_formatting_problem::get_attachment (Real y, Drul_array<int> columns) const
{
  Interval attachments (0,0);
  Direction d = LEFT;
  do
    {
      Tuple2<int> key (columns[d], int (d));
      Chord_outline_map::const_iterator i (chord_outlines_.find (key));
      if (i == chord_outlines_.end ())
        programming_error ("Can't find chord outline");
      else
        attachments[d] = skyline_height ((*i).second, y, -d);
    }
  while (flip (&d) != LEFT);
  
  return attachments;
}

Tie_formatting_problem::Tie_formatting_problem()
{
  x_refpoint_ = 0;
}

Tie_formatting_problem::~Tie_formatting_problem ()
{
  for (Tie_configuration_map::const_iterator i (possibilities_.begin ());
       i != possibilities_.end (); i++)
    delete (*i).second;
}

void
Tie_formatting_problem::set_column_chord_outline (vector<Item*> bounds,
                                                  Direction dir,
                                                  int column_rank)
{
  Real staff_space = Staff_symbol_referencer::staff_space (bounds[0]);

  vector<Box> boxes;
  vector<Box> head_boxes;

  Grob *stem = 0;
  for (vsize i = 0; i < bounds.size (); i++)
    {
      Grob *head = bounds[i];
      if (!Note_head::has_interface (head))
        continue;
          
      if (!stem)
        stem = unsmob_grob (head->get_object ("stem"));
          
      Real p = Staff_symbol_referencer::get_position (head);
      Interval y ((p-1) * 0.5 * staff_space,
                  (p+1) * 0.5 * staff_space);

      Interval x = head->extent (x_refpoint_, X_AXIS);
      head_boxes.push_back (Box (x, y));
      boxes.push_back (Box (x, y));

      Grob *dots = Rhythmic_head::get_dots (head);
      if (dir == LEFT && dots)
        {
          Interval x = dots->extent (x_refpoint_, X_AXIS);
          int p = int (Staff_symbol_referencer::get_position (dots));

          dot_positions_.insert (p);
          dot_x_.unite (x);

          Interval y (dots->extent (dots, Y_AXIS));
          y.translate (p * staff_space * 0.5);
          
          boxes.push_back (Box (x, y));
        }
    }

  Tuple2<int> key (column_rank, int (dir));
  
  chord_outlines_[key] = empty_skyline (-dir);
      
  if (bounds[0]->break_status_dir ())
    {
      Real x = robust_relative_extent (bounds[0],  x_refpoint_, X_AXIS)[-dir];
      chord_outlines_[key].at (0).height_ = x; 
    }
  else
    {
      Interval x;
      for (vsize j = 0; j < head_boxes.size (); j++)
        {
          x.unite (head_boxes[j][X_AXIS]);
        }
      
      chord_outlines_[key].at (0).height_ = x[dir];
    }
      
  for (vsize i = 0; i < boxes.size (); i++)
    insert_extent_into_skyline (&chord_outlines_[key]  ,
                                boxes[i], Y_AXIS, -dir);

  if (stem
      && !Stem::is_invisible (stem))
    {
      Interval x;
      x.add_point (stem->relative_coordinate (x_refpoint_, X_AXIS));
      x.widen (staff_space / 20); // ugh.
      Interval y;
      y.add_point (Stem::stem_end_position (stem) * staff_space * .5);

      Direction stemdir = get_grob_direction (stem);
      y.add_point (Stem::head_positions (stem)[-stemdir]
                   * staff_space * .5);
          
      insert_extent_into_skyline (&chord_outlines_[key], Box (x,y), Y_AXIS, -dir);

      stem_extents_[key].unite (Box (x,y));

      if (dir == LEFT)
        {
          Box flag_box = Stem::get_translated_flag (stem).extent_box ();
          flag_box.translate( Offset (x[RIGHT], X_AXIS));
          insert_extent_into_skyline (&chord_outlines_[key], flag_box,
                                      Y_AXIS, -dir);
        }
    }
  else if (stem)
    {
      Grob *head = Stem::support_head (stem);

      /*
        In case of invisible stem, don't pass x-center of heads.
       */
      Real x_center = head->extent (x_refpoint_, X_AXIS).center ();
      Interval x_ext;
      x_ext[-dir] = x_center;
      Interval y_ext;
      for (vsize j = 0; j < head_boxes.size (); j++)
        y_ext.unite (head_boxes[j][Y_AXIS]);
          
      insert_extent_into_skyline (&chord_outlines_[key],
                                  Box (x_ext, y_ext),
                                  Y_AXIS, -dir);
    }
  
  Direction updowndir = DOWN;
  do
    {
      Interval x;
      Interval y;
      if (head_boxes.size())
        {
          Box b = boundary (head_boxes, updowndir, 0);
          x = b[X_AXIS];
          x[-dir] =  b[X_AXIS].linear_combination (-dir / 2);
          y[-updowndir] = b[Y_AXIS][updowndir];
          y[updowndir] = updowndir * infinity_f;
        }

      if (!x.is_empty ())
        insert_extent_into_skyline (&chord_outlines_[key],
                                    Box (x,y),
                                    Y_AXIS, -dir);
    }
  while (flip (&updowndir) != DOWN);
  
  head_extents_[key].set_empty ();
  for (vsize i = 0; i < head_boxes.size (); i++)
    {
      head_extents_[key].unite (head_boxes[i]);
    }
}

void
Tie_formatting_problem::set_chord_outline (vector<Item*> bounds,
                                           Direction dir)

{
  vector<int> ranks;
  for (vsize i = 0; i < bounds.size (); i++)
    ranks.push_back (bounds[i]->get_column ()->get_rank ());

  vector_sort (ranks, less<int> ());
  uniq (ranks);

  for (vsize i = 0; i < ranks.size (); i++)
    {
      vector<Item*> col_items;
      for (vsize j = 0; j < bounds.size (); j ++)
        {
          if (bounds[j]->get_column ()->get_rank () == ranks[i])
            col_items.push_back (bounds[j]);
        }

      set_column_chord_outline (col_items, dir, ranks[i]);
    }
}
  


void
Tie_formatting_problem::from_tie (Grob *tie)
{
  vector<Grob*> ties;
  ties.push_back (tie);
  from_ties (ties);

  details_.from_grob (tie);
}

Grob *
Tie_formatting_problem::common_x_refpoint () const
{
  return x_refpoint_;
}

void
Tie_formatting_problem::from_ties (vector<Grob*> const &ties)
{
  if (ties.empty ())
    return;
  
  x_refpoint_ = ties[0];
  for (vsize i = 0; i < ties.size (); i++)
    {
      x_refpoint_ = dynamic_cast<Spanner*> (ties[i])->get_bound (LEFT)->common_refpoint (x_refpoint_, X_AXIS); 
      x_refpoint_ = dynamic_cast<Spanner*> (ties[i])->get_bound (RIGHT)->common_refpoint (x_refpoint_, X_AXIS); 
    }

  details_.from_grob (ties[0]);
  
  Direction d = LEFT;
  do
    {
      vector<Item*> bounds;
      
      for (vsize i = 0; i < ties.size (); i++)
        {
          Item *it = dynamic_cast<Spanner*> (ties[i])->get_bound (d);
                                             
          bounds.push_back (it);
        }
      
      set_chord_outline (bounds, d);
    }
  while (flip (&d) != LEFT);


  for (vsize i = 0; i < ties.size (); i++)
    {
      Tie_specification spec;
      
      if (scm_is_number (ties[i]->get_property_data (ly_symbol2scm ("direction"))))
        {
          spec.manual_dir_ = to_dir (ties[i]->get_property ("direction"));
          spec.has_manual_dir_ = true;
        }
          
      spec.position_ = Tie::get_position (ties[i]);
      if (scm_is_number (ties[i]->get_property ("staff-position")))
        {
          spec.manual_position_ = scm_to_double (ties[i]->get_property ("staff-position"));
          spec.has_manual_position_ = true;
          spec.position_ = int (my_round (spec.manual_position_));
        }
      
      do
        {
          spec.note_head_drul_[d] = Tie::head (ties[i], d);
          spec.column_ranks_[d] =
            dynamic_cast<Spanner*> (ties[i])->get_bound (d)->get_column ()->get_rank ();
        }
      while (flip (&d) != LEFT);
      specifications_.push_back (spec);
    }
}

void
Tie_formatting_problem::from_semi_ties (vector<Grob*> const &lv_ties, Direction head_dir)
{
  if (lv_ties.empty ())
    return;
  
  details_.from_grob (lv_ties[0]);
  vector<Item*> heads;

  int column_rank = -1;
  for (vsize i = 0; i < lv_ties.size (); i++)
    {
      Tie_specification spec;
      Item *head = unsmob_item (lv_ties[i]->get_object ("note-head"));
       
      if (!head)
        programming_error ("LV tie without head?!");

      if (head)
        {
          spec.position_ = int (Staff_symbol_referencer::get_position (head));
        }
      

      spec.note_head_drul_[head_dir] = head;
      column_rank = dynamic_cast<Item*> (head)->get_column ()->get_rank ();
      spec.column_ranks_ = Drul_array<int> (column_rank, column_rank);
      heads.push_back (head);
      specifications_.push_back (spec);
    }

  x_refpoint_ = lv_ties [0];
  for (vsize i = 0; i < lv_ties.size (); i++)
    x_refpoint_ = lv_ties[i]->common_refpoint (x_refpoint_, X_AXIS); 
  for (vsize i = 0; i < heads.size (); i++)
    x_refpoint_ = heads[i]->common_refpoint (x_refpoint_, X_AXIS); 

  set_chord_outline (heads, head_dir);

  Real extremal = head_dir * infinity_f;   

  Tuple2<int> head_key (column_rank, head_dir);
  Tuple2<int> open_key (column_rank, -head_dir);
  
  for (vsize i = 0; i < chord_outlines_[head_key].size (); i++)
    {
      extremal = head_dir * min (head_dir * extremal,
                                 head_dir * chord_outlines_[head_key][i].height_);
    }

  Skyline_entry right_entry;
  right_entry.width_.set_full ();
  right_entry.height_ = extremal - head_dir * 1.5;
  
  chord_outlines_[open_key].push_back (right_entry);
}


Tie_specification
Tie_formatting_problem::get_tie_specification (int i) const
{
  return specifications_[i];
}


/*
  Return configuration, create it if necessary. 
*/
Tie_configuration*
Tie_formatting_problem::get_configuration (int pos, Direction dir, Drul_array<int> columns) const
{
  int key_components[] = {
    pos, dir, columns[LEFT], columns[RIGHT]
  };
  Tuple<int,4> key (key_components);
    
  Tie_configuration_map::const_iterator f = possibilities_.find (key);
  if (f != possibilities_.end ())
    {
      return (*f).second;
    }

  
  Tie_configuration *conf = generate_configuration (pos, dir, columns);
  ((Tie_formatting_problem*) this)->possibilities_[key] = conf;
  return conf;
}

Tie_configuration*
Tie_formatting_problem::generate_configuration (int pos, Direction dir,
                                                Drul_array<int> columns) const
{
  Tie_configuration *conf = new Tie_configuration;
  conf->position_ = pos;
  conf->dir_ = dir;
  
  conf->column_ranks_ = columns;
  
  Real y = conf->position_ * 0.5 * details_.staff_space_;

  bool y_tune = true;
  if (dot_positions_.find (pos) != dot_positions_.end ())
    {
      conf->delta_y_ += dir * 0.25 * details_.staff_space_;
      y_tune = false;
    }
  
  if (y_tune
      && max (fabs (get_head_extent (columns[LEFT], LEFT, Y_AXIS)[dir] - y),
              fabs (get_head_extent (columns[RIGHT], RIGHT, Y_AXIS)[dir] - y)) < 0.25
      && !Staff_symbol_referencer::on_line (details_.staff_symbol_referencer_, pos))
    {
      conf->delta_y_ =
        (get_head_extent (columns[LEFT], LEFT, Y_AXIS)[dir] - y)
        + dir * details_.outer_tie_vertical_gap_;
    }

  if (y_tune)
    {
      conf->attachment_x_ = get_attachment (y + conf->delta_y_, conf->column_ranks_);
      Real h =  conf->height (details_);
      
      /*
        TODO:

        - should make sliding criterion, should flatten ties if

        - they're just the wrong (ie. touching line at top & bottom)
        size.
        
       */
      if (h < details_.intra_space_threshold_ * 0.5 * details_.staff_space_)
        {
          if (!Staff_symbol_referencer::on_line (details_.staff_symbol_referencer_, pos)
              && abs (pos) < 2 * Staff_symbol_referencer::staff_radius (details_.staff_symbol_referencer_))
            {
              conf->center_tie_vertically (details_);
            }
          else if (Staff_symbol_referencer::on_line (details_.staff_symbol_referencer_, pos))
            {
              conf->delta_y_ += dir *
                details_.tip_staff_line_clearance_ * 0.5 *  details_.staff_space_;
            }
        }
      else 
        {
          Real top_y = y + conf->delta_y_ + conf->dir_ * h;
          Real top_pos = top_y / (0.5*details_.staff_space_);
          int round_pos = int (my_round (top_pos));

          /* TODO: should use other variable? */
          Real clearance = details_.center_staff_line_clearance_;
          if (fabs (top_pos - round_pos) < clearance
              && Staff_symbol_referencer::on_staff_line (details_.staff_symbol_referencer_,
                                                         round_pos))
            {
              Real new_y = (round_pos + clearance * conf->dir_) * 0.5 * details_.staff_space_;
              conf->delta_y_ = (new_y - top_y);
            }
        }
    }
  
  conf->attachment_x_ = get_attachment (y + conf->delta_y_, conf->column_ranks_);
  if (conf->height (details_) < details_.intra_space_threshold_ * 0.5 * details_.staff_space_)
    {
      /*
        This is less sensible for long ties, since those are more
        horizontal.
      */
      Interval close_by = get_attachment (y
                                          + conf->delta_y_
                                          + (dir * details_.intra_space_threshold_ * 0.25
                                             * details_.staff_space_),
                                          conf->column_ranks_);
      
      conf->attachment_x_.intersect (close_by);
    }

  conf->attachment_x_.widen ( - details_.x_gap_);

  Direction d = LEFT;
  do
    {
      Real y = conf->position_ * details_.staff_space_ * 0.5 + conf->delta_y_;
      if (get_stem_extent (conf->column_ranks_[d], d, X_AXIS).is_empty ()
          || !get_stem_extent (conf->column_ranks_[d], d, Y_AXIS).contains (y))
        continue;

      conf->attachment_x_[d] =
        d * min (d * conf->attachment_x_[d],
                 d * (get_stem_extent (conf->column_ranks_[d], d, X_AXIS)[-d] - d * details_.stem_gap_));
    }
  while (flip (&d) != LEFT);
  
  return conf;
}

Interval
Tie_formatting_problem::get_head_extent (int col, Direction d, Axis a) const
{
  return (*head_extents_.find (Tuple2<int> (col, int (d)))).second[a];
}

Interval
Tie_formatting_problem::get_stem_extent (int col, Direction d, Axis a) const
{
  return (*stem_extents_.find (Tuple2<int> (col, int (d)))).second[a];
}

/**
   TIE_IDX and TIES_CONF are optional.
 */
Real
Tie_formatting_problem::score_aptitude (Tie_configuration *conf,
                                        Tie_specification const &spec,
                                        Ties_configuration *ties_conf, int tie_idx) const
{
  Real penalty = 0.0;
  Real curve_y = conf->position_ * details_.staff_space_ * 0.5 + conf->delta_y_;
  Real tie_y = spec.position_ * details_.staff_space_ * 0.5;
  if (sign (curve_y - tie_y) != conf->dir_)
    {
      Real p =  details_.wrong_direction_offset_penalty_;
      if (ties_conf)
        ties_conf->add_tie_score (p, tie_idx, "wrong dir");
      else
        penalty += p;
    }

  {
    Real p = details_.vertical_distance_penalty_factor_ * fabs (curve_y - tie_y);
    if (ties_conf)
      ties_conf->add_tie_score (p, tie_idx, "vdist");
    else
      penalty += p; 
  }
  
  Direction d = LEFT;
  do
    {
      if (!spec.note_head_drul_[d])
        continue;
      
      Interval head_x = spec.note_head_drul_[d]->extent (x_refpoint_, X_AXIS);
      Real dist = head_x.distance (conf->attachment_x_[d]);

      /*
        TODO: flatten with log or sqrt.
       */
      Real p = details_.horizontal_distance_penalty_factor_ * dist;
      if (ties_conf)
        ties_conf->add_tie_score (p, tie_idx,
                                  (d == LEFT) ? "lhdist" : "rhdist");
      else
        penalty += p;
    }
  while (flip (&d) != LEFT);

  return penalty;
}

void
Tie_formatting_problem::score_configuration (Tie_configuration *conf) const
{
  if (conf->scored_)
    {
      return ;
    }
  
  Real length = conf->attachment_x_.length ();

  conf->add_score (details_.min_length_penalty_factor_
                   * peak_around (0.33 * details_.min_length_, details_.min_length_, length),
                   "minlength");
  
  Real tip_pos = conf->position_ + conf->delta_y_ / 0.5 * details_.staff_space_;
  Real tip_y = tip_pos * details_.staff_space_ * 0.5;
  Real height =  conf->height (details_);

  Real top_y = tip_y + conf->dir_ * height;
  Real top_pos = 2 * top_y / details_.staff_space_;
  Real round_top_pos = rint (top_pos);
  if (Staff_symbol_referencer::on_line (details_.staff_symbol_referencer_,
                                                int (round_top_pos))
      && Staff_symbol_referencer::staff_radius (details_.staff_symbol_referencer_) > top_y)
    {
      conf->add_score (
        details_.staff_line_collision_penalty_
        * peak_around (0.1 * details_.center_staff_line_clearance_,
                     details_.center_staff_line_clearance_,
                       fabs (top_pos - round_top_pos)),
        "line center");
    }
  
  if (Staff_symbol_referencer::on_line (details_.staff_symbol_referencer_,
                                        int (rint (tip_pos))))
    {
      conf->add_score (details_.staff_line_collision_penalty_
                       * peak_around (0.1 * details_.tip_staff_line_clearance_,
                                      details_.tip_staff_line_clearance_,
                                      fabs (tip_pos - rint (tip_pos))),
                       "tipline");
    }

  if (!dot_x_.is_empty ())
    {
      /* use left edge? */
      Real x = dot_x_.center ();
      
      Bezier b = conf->get_transformed_bezier (details_);
      if (b.control_point_extent (X_AXIS).contains (x))
        {
          Real y = b.get_other_coordinate (X_AXIS, x);

          for (set<int>::const_iterator i (dot_positions_.begin ());
               i != dot_positions_.end (); i ++)
            {
              int dot_pos = (*i);
              conf->add_score (details_.dot_collision_penalty_
                * peak_around (.1 * details_.dot_collision_clearance_,
                               details_.dot_collision_clearance_,
                               fabs (dot_pos * details_.staff_space_ * 0.5 - y)),
                               "dot collision");
            }
        }
    }

  conf->scored_ = true;
}

Tie_configuration
Tie_formatting_problem::find_optimal_tie_configuration (Tie_specification const &spec) const
{
  vector<Tie_configuration*> confs;

  int pos = spec.position_;
  Direction dir = spec.manual_dir_;

  for (int i = 0; i < details_.single_tie_region_size_; i ++)
    {
      confs.push_back (generate_configuration (pos + i * dir, dir,
                                               spec.column_ranks_));
      
      if (spec.has_manual_position_)
        {
          confs.back ()->delta_y_
            = (spec.manual_position_ - spec.position_)
            * 0.5 * details_.staff_space_;

          break;
        }
    }

  vector<Real> scores;

  int best_idx = -1;
  Real best_score = 1e6;
  for (vsize i = 0; i < confs.size (); i ++)
    {
      score_configuration (confs[i]);
      Real score = score_aptitude (confs[i], spec, 0, 0)
        + confs[i]->score ();

      if (score < best_score)
        {
          best_score = score;
          best_idx = i;
        }
    }

  if (best_idx < 0)
    programming_error ("No best tie configuration found.");

  Tie_configuration best
    = (best_idx >= 0) ?  *confs[best_idx] : *confs[0];
  
  for (vsize i = 0; i < confs.size (); i++)
    delete confs[i];

  return best;
}

Tie_specification::Tie_specification ()
{
  has_manual_position_ = false;
  has_manual_dir_ = false;
  position_ = 0;
  manual_position_ = 0;
  manual_dir_ = CENTER;
  note_head_drul_[LEFT] =
    note_head_drul_[RIGHT] = 0;
  column_ranks_[RIGHT] =
    column_ranks_[LEFT] = 0;
}

int
Tie_specification::column_span () const
{
  return column_ranks_[RIGHT] - column_ranks_[LEFT];
}

void
Tie_formatting_problem::score_ties_aptitude (Ties_configuration *ties) const
{
  if  (ties->size () != specifications_.size ())
    {
      programming_error ("Huh? Mismatch between sizes.");
      return;
    }

  for (vsize i = 0; i < ties->size (); i++)
    score_aptitude (&ties->at (i), specifications_[i],
                    ties, i);
}

void
Tie_formatting_problem::score_ties (Ties_configuration *ties) const
{
  if (ties->scored_)
    return;
  
  score_ties_configuration (ties);
  score_ties_aptitude (ties);
  ties->scored_ = true;
}

void
Tie_formatting_problem::score_ties_configuration (Ties_configuration *ties) const
{
  for (vsize i = 0; i < ties->size (); i++)
    {
      score_configuration (&ties->at (i));
      ties->add_tie_score (ties->at (i).score (), i, "conf");
    }
  
  Real last_edge = 0.0;
  Real last_center = 0.0;
  for (vsize i = 0; i < ties->size (); i++)
    {
      Bezier b (ties->at (i).get_transformed_bezier (details_));
        
      Real center = b.curve_point (0.5)[Y_AXIS];
      Real edge = b.curve_point (0.0)[Y_AXIS];
      
      if (i)
        {
          if (edge <= last_edge)
            ties->add_score (details_.tie_column_monotonicity_penalty_, "monoton edge");
          if (center <= last_center)
            ties->add_score (details_.tie_column_monotonicity_penalty_, "monoton cent");

          ties->add_score (details_.tie_tie_collision_penalty_ *
                           peak_around (0.1 * details_.tie_tie_collision_distance_,
                                        details_.tie_tie_collision_distance_,
                                        fabs (center - last_center)),
                           "tietie center");
          ties->add_score (details_.tie_tie_collision_penalty_ *
                           peak_around (0.1 * details_.tie_tie_collision_distance_,
                                        details_.tie_tie_collision_distance_,
                                        fabs (edge - last_edge)), "tietie edge");
        }

      last_edge = edge;
      last_center = center;
    }

  ties->add_score (details_.outer_tie_length_symmetry_penalty_factor_
                   * fabs (ties->at (0).attachment_x_.length () - ties->back ().attachment_x_.length ()),
                   "length symm");
  
  ties->add_score (details_.outer_tie_vertical_distance_symmetry_penalty_factor_
                   * fabs (fabs (specifications_[0].position_ * 0.5 * details_.staff_space_
                                 - (ties->at (0).position_ * 0.5 * details_.staff_space_
                                    + ties->at (0).delta_y_))
                           -
                           fabs (specifications_.back ().position_ * 0.5 * details_.staff_space_
                                 - (ties->back ().position_ * 0.5 * details_.staff_space_
                                    + ties->back ().delta_y_))),
                   "pos symmetry");
}

/*
  Generate with correct X-attachments and beziers, copying delta_y_
  from TIES_CONFIG if necessary.
*/
Ties_configuration
Tie_formatting_problem::generate_ties_configuration (Ties_configuration const &ties_config)
{
  Ties_configuration copy;
  for (vsize i = 0; i < ties_config.size (); i++)
    {
      Tie_configuration * ptr = get_configuration (ties_config[i].position_, ties_config[i].dir_,
                                                   ties_config[i].column_ranks_);
      if (specifications_[i].has_manual_position_)
        {
          ptr->delta_y_
            = (specifications_[i].manual_position_ - ties_config[i].position_)
            * 0.5 * details_.staff_space_;
        }
      copy.push_back (*ptr);
    }
  
  return copy;
}

Ties_configuration
Tie_formatting_problem::generate_base_chord_configuration () 
{
  Ties_configuration ties_config;
  for (vsize i = 0;  i < specifications_.size (); i ++)
    {
      Tie_configuration conf;
      if (specifications_[i].has_manual_dir_)
        conf.dir_ = specifications_[i].manual_dir_;
      if (specifications_[i].has_manual_position_)
        {
          conf.position_ = (int) my_round (specifications_[i].manual_position_);
          conf.delta_y_ = (specifications_[i].manual_position_ - conf.position_)
            * 0.5 * details_.staff_space_;
        }
      else
        {
          conf.position_ = specifications_[i].position_;
        }

      conf.column_ranks_ = specifications_[i].column_ranks_;
      ties_config.push_back (conf);
    }

  set_ties_config_standard_directions (&ties_config);
  for (vsize i = 0; i < ties_config.size (); i++)
    if (!specifications_[i].manual_position_)
      ties_config[i].position_ += ties_config[i].dir_;

  ties_config = generate_ties_configuration (ties_config);
  
  return ties_config;
}

Ties_configuration
Tie_formatting_problem::find_best_variation (Ties_configuration const &base,
                                             vector<Tie_configuration_variation> vars)
{
  Ties_configuration best = base;
  
  /*
    This simply is 1-opt: we have K substitions, and we try applying
    exactly every one for each.
  */
  for (vsize i = 0; i < vars.size (); i++)
    {
      Ties_configuration variant (base);
      variant[vars[i].index_] = *vars[i].suggestion_;

      variant.reset_score ();
      score_ties (&variant);
      
      if (variant.score () < best.score ())
        {
          best = variant;
        }
    }

  return best;
}
  
                                       

Ties_configuration
Tie_formatting_problem::generate_optimal_chord_configuration ()
{
  Ties_configuration base = generate_base_chord_configuration ();
  vector<Tie_configuration_variation> vars = generate_collision_variations (base);
  
  score_ties (&base);
  Ties_configuration best = find_best_variation (base, vars);
  vars = generate_extremal_tie_variations (best);
  best = find_best_variation (best, vars);

  return best;
}

void
Tie_formatting_problem::set_ties_config_standard_directions (Ties_configuration *tie_configs)
{
  if (tie_configs->empty ())
    return ;
  
  if (!tie_configs->at (0).dir_)
    tie_configs->at (0).dir_ = DOWN;
  if (!tie_configs->back ().dir_)
    tie_configs->back ().dir_ = UP;

  /*
    Seconds
   */
  for (vsize i = 1; i < tie_configs->size (); i++)
    {
      Real diff = (tie_configs->at (i).position_
                   -tie_configs->at (i-1).position_);
                   
      Real span_diff 
        = specifications_[i].column_span () - specifications_[i-1].column_span ();
      if (span_diff && fabs (diff) <= 2)
        {
          if  (span_diff > 0)
            tie_configs->at (i).dir_ = UP;
          else if (span_diff < 0)
            tie_configs->at (i-1).dir_ = DOWN;  
        }
      else if (fabs (diff) <= 1)
        {
          if (!tie_configs->at (i-1).dir_)
            tie_configs->at (i-1).dir_ = DOWN;
          if (!tie_configs->at (i).dir_)
            tie_configs->at (i).dir_ = UP;
        }
    }

  for (vsize i = 1; i < tie_configs->size() - 1; i++)
    {
      Tie_configuration &conf = tie_configs->at (i);
      if (conf.dir_)
        continue;

      Direction position_dir =
        Direction (sign (conf.position_));
      if (!position_dir)
        position_dir = DOWN;

      conf.dir_ = position_dir;
    }
}

Tie_configuration_variation::Tie_configuration_variation ()
{
  index_ = 0;
  suggestion_ = 0;
}

vector<Tie_configuration_variation>
Tie_formatting_problem::generate_extremal_tie_variations (Ties_configuration const &ties) const
{
  vector<Tie_configuration_variation> vars;
  Direction d = DOWN;
  do
    {
      if (boundary (ties, d, 0).dir_ == d
          && !boundary (specifications_, d, 0).has_manual_position_)
        for (int i = 1; i <= details_.multi_tie_region_size_; i++)
          {
            Tie_configuration_variation var;
            var.index_ = (d == DOWN) ? 0 : ties.size () - 1;
            var.suggestion_ = get_configuration (boundary (ties, d, 0).position_
                                                 + d * i, d,
                                                 boundary (ties, d, 0).column_ranks_);
            vars.push_back (var);
          }
    }
  while (flip (&d) !=  DOWN);

  return vars;
}


vector<Tie_configuration_variation>
Tie_formatting_problem::generate_collision_variations (Ties_configuration const &ties) const
{
  Real center_distance_tolerance = 0.25;
  
  vector<Tie_configuration_variation> vars;
  Real last_center = 0.0;
  for (vsize i = 0; i < ties.size (); i++)
    {
      Bezier b (ties[i].get_transformed_bezier (details_));
        
      Real center = b.curve_point (0.5)[Y_AXIS];
      
      if (i)
        {
          if (center <= last_center + center_distance_tolerance)
            {
              if (!specifications_[i].has_manual_dir_)
                {
                  Tie_configuration_variation var;
                  var.index_ = i;
                  var.suggestion_ = get_configuration (specifications_[i].position_
                                                       - ties[i].dir_,
                                                       - ties[i].dir_,

                                                       ties[i].column_ranks_
                                                       );

                  vars.push_back (var);
                }

              if (!specifications_[i-1].has_manual_dir_)
                {
                  Tie_configuration_variation var;
                  var.index_ = i-1;
                  var.suggestion_ = get_configuration (specifications_[i-1].position_
                                                       - ties[i-1].dir_,
                                                       - ties[i-1].dir_,
                                                       specifications_[i-1].column_ranks_);

                  vars.push_back (var);
                }

              if (i == 1 && !specifications_[i-1].has_manual_position_
                  && ties[i-1].dir_ == DOWN)
                {
                  Tie_configuration_variation var;
                  var.index_ = i-1;
                  var.suggestion_ = get_configuration (specifications_[i-1].position_ - 1, DOWN,
                                                       specifications_[i-1].column_ranks_);
                  vars.push_back (var);
                }
              if (i == ties.size() && !specifications_[i].has_manual_position_
                  && ties[i].dir_ == UP)
                {
                  Tie_configuration_variation var;
                  var.index_ = i;
                  var.suggestion_ = get_configuration (specifications_[i].position_
                                                       + 1, UP,
                                                       specifications_[i].column_ranks_);
                  vars.push_back (var);
                }
            }
          else if (dot_positions_.find (ties[i].position_) != dot_positions_.end ()
                   && !specifications_[i].has_manual_position_)
            {
              Tie_configuration_variation var;
              var.index_ = i;
              var.suggestion_ = get_configuration (ties[i].position_  + ties[i].dir_,
                                                   ties[i].dir_,
                                                   ties[i].column_ranks_);
              vars.push_back (var);
            }
          
        }

      last_center = center;
    }


  return vars;
}

void
Tie_formatting_problem::set_manual_tie_configuration (SCM manual_configs)
{
  vsize k = 0;
  for (SCM s = manual_configs;
       scm_is_pair (s) && k < specifications_.size (); s = scm_cdr (s))
    {
      SCM entry = scm_car (s);
      if (scm_is_pair (entry))
        {
          Tie_specification &spec = specifications_[k];

          if (scm_is_number (scm_car (entry)))
            {
              spec.has_manual_position_ = true;
              spec.manual_position_ = scm_to_double (scm_car (entry));
            }
          if (scm_is_number (scm_cdr (entry)))
            {
              spec.has_manual_dir_ = true;
              spec.manual_dir_ = Direction (scm_to_int (scm_cdr (entry)));
            }
        }         
      k ++;
    }
}