lily/slur-configuration.cc

   1 /*
   2   slur-configuration.cc -- implement Slur_configuration
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2004--2005 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "slur-configuration.hh"
  10
  11 #include <math.h>
  12
  13 #include "stem.hh"
  14 #include "warn.hh"
  15 #include "misc.hh"
  16 #include "item.hh"
  17 #include "group-interface.hh"
  18 #include "slur.hh"
  19 #include "slur-scoring.hh"
  20 #include "spanner.hh"
  21 #include "staff-symbol-referencer.hh"
  22 #include "libc-extension.hh"
  23
  24 Bezier
  25 avoid_staff_line (Slur_score_state const &state,
  26                   Bezier bez)
  27 {
  28   Offset horiz (1, 0);
  29   Array<Real> ts = bez.solve_derivative (horiz);
  30
  31   /* TODO: handle case of broken slur.  */
  32   if (!ts.is_empty ()
  33       && (state.extremes_[LEFT].staff_ == state.extremes_[RIGHT].staff_)
  34       && state.extremes_[LEFT].staff_ && state.extremes_[RIGHT].staff_)
  35     {
  36       Real y = bez.curve_point (ts[0])[Y_AXIS];
  37
  38       Grob *staff = state.extremes_[LEFT].staff_;
  39
  40       Real p = 2 * (y - staff->relative_coordinate (state.common_[Y_AXIS], Y_AXIS))
  41         / state.staff_space_;
  42
  43       Real distance = fabs (my_round (p) - p);  //  in halfspaces
  44       if (distance < 4 * state.thickness_
  45           && (int) fabs (my_round (p))
  46           <= 2 * Staff_symbol_referencer::staff_radius (staff) + 0.1
  47           && (int (fabs (my_round (p))) % 2
  48               != Staff_symbol_referencer::line_count (staff) % 2))
  49         {
  50           Direction resolution_dir
  51             = (distance ? state.dir_ : Direction (sign (p - my_round (p))));
  52
  53           // TODO: parameter
  54           Real newp = my_round (p) + resolution_dir
  55             * 5 * state.thickness_;
  56
  57           Real dy = (newp - p) * state.staff_space_ / 2.0;
  58
  59           bez.control_[1][Y_AXIS] += dy;
  60           bez.control_[2][Y_AXIS] += dy;
  61         }
  62     }
  63   return bez;
  64 }
  65
  66 Real
  67 fit_factor (Offset dz_unit, Offset dz_perp,
  68             Bezier curve, Direction d, Array<Offset> const &avoid)
  69 {
  70   Real fit_factor = 0.0;
  71   Offset x0 = curve.control_[0];
  72   curve.translate (-x0);
  73   curve.rotate (-dz_unit.arg ());
  74   curve.scale (1, d);
  75
  76   Interval curve_xext;
  77   curve_xext.add_point (curve.control_[0][X_AXIS]);
  78   curve_xext.add_point (curve.control_[3][X_AXIS]);
  79
  80   for (int i = 0; i < avoid.size (); i++)
  81     {
  82       Offset z = (avoid[i] - x0);
  83       Offset p (dot_product (z, dz_unit),
  84                 d * dot_product (z, dz_perp));
  85       if (!curve_xext.contains (p[X_AXIS]))
  86         continue;
  87
  88       Real y = curve.get_other_coordinate (X_AXIS, p[X_AXIS]);
  89       if (y)
  90         {
  91           fit_factor = max (fit_factor, (p[Y_AXIS] / y));
  92         }
  93     }
  94   return fit_factor;
  95 }
  96
  97 void
  98 Slur_configuration::generate_curve (Slur_score_state const &state,
  99                                     Real r_0, Real h_inf)
 100 {
 101   Link_array<Grob> encompasses = state.columns_;
 102
 103   Array<Offset> avoid;
 104   for (int i = 0; i < encompasses.size (); i++)
 105     {
 106       if (state.extremes_[LEFT].note_column_ == encompasses[i]
 107           || state.extremes_[RIGHT].note_column_ == encompasses[i])
 108         continue;
 109
 110       Encompass_info inf (state.get_encompass_info (encompasses[i]));
 111       Real y = state.dir_ * (max (state.dir_ * inf.head_, state.dir_ * inf.stem_));
 112
 113       avoid.push (Offset (inf.x_, y + state.dir_ * state.parameters_.free_head_distance_));
 114     }
 115
 116   Link_array<Grob> extra_encompasses
 117     = extract_grob_array (state.slur_, ly_symbol2scm ("encompass-objects"));
 118   for (int i = 0; i < extra_encompasses.size (); i++)
 119     if (Slur::has_interface (extra_encompasses[i]))
 120       {
 121         Grob *small_slur = extra_encompasses[i];
 122         Bezier b = Slur::get_curve (small_slur);
 123
 124         Offset z = b.curve_point (0.5);
 125         z += Offset (small_slur->relative_coordinate (state.common_[X_AXIS], X_AXIS),
 126                      small_slur->relative_coordinate (state.common_[Y_AXIS], Y_AXIS));
 127
 128         z[Y_AXIS] += state.dir_ * state.parameters_.free_slur_distance_;
 129         avoid.push (z);
 130       }
 131
 132   Offset dz = attachment_[RIGHT]- attachment_[LEFT];;
 133   Offset dz_unit = dz;
 134   dz_unit *= 1 / dz.length ();
 135   Offset dz_perp = dz_unit * Offset (0, 1);
 136
 137   Real indent, height;
 138   get_slur_indent_height (&indent, &height, dz.length (), h_inf, r_0);
 139
 140   Real len = dz.length ();
 141
 142   /* This condition,
 143
 144   len^2 > 4h^2 +  3 (i + 1/3len)^2  - 1/3 len^2
 145
 146   is equivalent to:
 147
 148   |bez' (0)| < | bez' (.5)|
 149
 150   when (control2 - control1) has the same direction as
 151   (control3 - control0).  */
 152
 153   Real max_indent = len / 3.1;
 154   indent = min (indent, max_indent);
 155
 156   Real a1 = sqr (len) / 3.0;
 157   Real a2 = 0.75 * sqr (indent + len / 3.0);
 158   Real max_h = a1 - a2;
 159
 160   if (max_h < 0)
 161     {
 162       programming_error ("slur indent too small");
 163       max_h = len / 3.0;
 164     }
 165   else
 166     {
 167       max_h = sqrt (max_h);
 168     }
 169
 170   Real excentricity = robust_scm2double (state.slur_->get_property ("excentricity"), 0);
 171
 172   Real x1 = (excentricity + indent);
 173   Real x2 = (excentricity - indent);
 174
 175   Bezier curve;
 176   curve.control_[0] = attachment_[LEFT];
 177   curve.control_[1] = attachment_[LEFT] + dz_perp * height * state.dir_
 178     + dz_unit * x1;
 179   curve.control_[2] = attachment_[RIGHT] + dz_perp * height * state.dir_
 180     + dz_unit * x2;
 181   curve.control_[3] = attachment_[RIGHT];
 182
 183   Real ff = fit_factor (dz_unit, dz_perp, curve, state.dir_, avoid);
 184
 185   height = max (height, min (height * ff, max_h));
 186
 187   curve.control_[0] = attachment_[LEFT];
 188   curve.control_[1] = attachment_[LEFT] + dz_perp * height * state.dir_
 189     + dz_unit * x1;
 190   curve.control_[2] = attachment_[RIGHT] + dz_perp * height * state.dir_
 191     + dz_unit * x2;
 192   curve.control_[3] = attachment_[RIGHT];
 193
 194   curve_ = avoid_staff_line (state, curve);
 195   height_ = height;
 196 }
 197
 198 Slur_configuration::Slur_configuration ()
 199 {
 200   score_ = 0.0;
 201   index_ = -1;
 202 };
 203
 204 void
 205 Slur_configuration::score_encompass (Slur_score_state const &state)
 206 {
 207   Bezier const &bez (curve_);
 208   Real demerit = 0.0;
 209
 210   /*
 211     Distances for heads that are between slur and line between
 212     attachment points.
 213   */
 214   Array<Real> convex_head_distances;
 215   for (int j = 0; j < state.encompass_infos_.size (); j++)
 216     {
 217       Real x = state.encompass_infos_[j].x_;
 218
 219       bool l_edge = j == 0;
 220       bool r_edge = j == state.encompass_infos_.size () - 1;
 221       bool edge = l_edge || r_edge;
 222
 223       if (! (x < attachment_[RIGHT][X_AXIS]
 224              && x > attachment_[LEFT][X_AXIS]))
 225         continue;
 226
 227       Real y = bez.get_other_coordinate (X_AXIS, x);
 228       if (!edge)
 229         {
 230           Real head_dy = (y - state.encompass_infos_[j].head_);
 231           if (state.dir_ * head_dy < 0)
 232             {
 233               demerit += state.parameters_.head_encompass_penalty_;
 234               convex_head_distances.push (0.0);
 235             }
 236           else
 237             {
 238               Real hd = (head_dy)
 239                 ? (1 / fabs (head_dy) - 1 / state.parameters_.free_head_distance_)
 240                 : state.parameters_.head_encompass_penalty_;
 241               hd = min (max (hd, 0.0), state.parameters_.head_encompass_penalty_);
 242
 243               demerit += hd;
 244             }
 245
 246           Real line_y = linear_interpolate (x,
 247                                             attachment_[RIGHT][X_AXIS],
 248                                             attachment_[LEFT][X_AXIS],
 249                                             attachment_[RIGHT][Y_AXIS],
 250                                             attachment_[LEFT][Y_AXIS]);
 251
 252           if (1) // state.dir_ * state.encompass_infos_[j].get_point (state.dir_) > state.dir_ *line_y )
 253             {
 254
 255               Real closest
 256                 = state.dir_ * max (state.dir_ * state.encompass_infos_[j].get_point (state.dir_), state.dir_ * line_y);
 257               Real d = fabs (closest - y);
 258
 259               convex_head_distances.push (d);
 260             }
 261         }
 262
 263       if (state.dir_ * (y - state.encompass_infos_[j].stem_) < 0)
 264         {
 265           Real stem_dem = state.parameters_.stem_encompass_penalty_;
 266           if ((l_edge && state.dir_ == UP)
 267               || (r_edge && state.dir_ == DOWN))
 268             stem_dem /= 5;
 269
 270           demerit += stem_dem;
 271         }
 272       else if (!edge)
 273         {
 274           Interval ext;
 275           ext.add_point (state.encompass_infos_[j].stem_);
 276           ext.add_point (state.encompass_infos_[j].head_);
 277
 278           // ?
 279           demerit += -state.parameters_.closeness_factor_
 280             * min (state.dir_
 281                    * (y - (ext[state.dir_] + state.dir_ * state.parameters_.free_head_distance_)), 0.0)
 282             / state.encompass_infos_.size ();
 283         }
 284     }
 285
 286   Real variance_penalty = 0.0;
 287
 288   if (convex_head_distances.size ())
 289     {
 290       Real avg_distance = 0.0;
 291       Real min_dist = infinity_f;
 292       for (int j = 0; j < convex_head_distances.size (); j++)
 293         {
 294           min_dist = min (min_dist, convex_head_distances[j]);
 295           avg_distance += convex_head_distances[j];
 296         }
 297
 298       /*
 299         For slurs over 3 or 4 heads, the average distance is not a
 300         good normalizer.
 301       */
 302       Real n = convex_head_distances.size ();
 303       if (n <= 2)
 304         {
 305           Real fact = 1.0;
 306           avg_distance += height_ * fact;
 307           n += fact;
 308         }
 309
 310       /*
 311         TODO: maybe it's better to use (avgdist - mindist)*factor
 312         as penalty.
 313       */
 314       avg_distance /= n;
 315       variance_penalty = state.parameters_.head_slur_distance_max_ratio_;
 316       if (min_dist > 0.0)
 317         variance_penalty
 318           = min ((avg_distance / (min_dist + state.parameters_.absolute_closeness_measure_) - 1.0),  variance_penalty);
 319
 320       variance_penalty = max (variance_penalty, 0.0);
 321       variance_penalty *= state.parameters_.head_slur_distance_factor_;
 322     }
 323
 324 #if DEBUG_SLUR_SCORING
 325   score_card_ += to_string ("C%.2f", demerit);
 326   score_card_ += to_string ("D%.2f", variance_penalty);
 327 #endif
 328
 329   score_ += demerit + variance_penalty;
 330 }
 331
 332 void
 333 Slur_configuration::score_extra_encompass (Slur_score_state const &state)
 334 {
 335   Real demerit = 0.0;
 336   for (int j = 0; j < state.extra_encompass_infos_.size (); j++)
 337     {
 338       Drul_array<Offset> attachment = attachment_;
 339       Interval slur_wid (attachment[LEFT][X_AXIS], attachment[RIGHT][X_AXIS]);
 340
 341       /*
 342         to prevent numerical inaccuracies in
 343         Bezier::get_other_coordinate ().
 344       */
 345       Direction d = LEFT;
 346       bool found = false;
 347       Real y = 0.0;
 348
 349       do
 350         {
 351           /*
 352             We need to check for the bound explicitly, since the
 353             slur-ending can be almost vertical, making the Y
 354             coordinate a bad approximation of the object-slur
 355             distance.
 356           */
 357           Item *as_item = dynamic_cast<Item *> (state.extra_encompass_infos_[j].grob_);
 358           if ((as_item
 359                && as_item->get_column ()
 360                == state.extremes_[d].bound_->get_column ())
 361               || state.extra_encompass_infos_[j].extents_[X_AXIS].contains (attachment[d][X_AXIS]))
 362             {
 363               y = attachment[d][Y_AXIS];
 364               found = true;
 365             }
 366         }
 367       while (flip (&d) != LEFT);
 368
 369       if (!found)
 370         {
 371           Real x = state.extra_encompass_infos_[j].extents_[X_AXIS]
 372             .linear_combination (state.extra_encompass_infos_[j].idx_);
 373
 374           if (!slur_wid.contains (x))
 375             continue;
 376
 377           y = curve_.get_other_coordinate (X_AXIS, x);
 378         }
 379
 380       Real dist = state.extra_encompass_infos_[j].extents_[Y_AXIS].distance (y);
 381       demerit
 382         += fabs (max (0.0, (state.parameters_.extra_encompass_free_distance_ - dist)))
 383         / state.parameters_.extra_encompass_free_distance_
 384         * state.extra_encompass_infos_[j].penalty_;
 385     }
 386 #if DEBUG_SLUR_SCORING
 387   score_card_ += to_string ("X%.2f", demerit);
 388 #endif
 389   score_ += demerit;
 390 }
 391
 392 void
 393 Slur_configuration::score_edges (Slur_score_state const &state)
 394 {
 395   Direction d = LEFT;
 396   Offset dz = attachment_[RIGHT]
 397     - attachment_[LEFT];
 398   Real slope = dz[Y_AXIS] / dz[X_AXIS];
 399   do
 400     {
 401       Real y = attachment_[d][Y_AXIS];
 402       Real dy = fabs (y - state.base_attachments_[d][Y_AXIS]);
 403
 404       Real factor = state.parameters_.edge_attraction_factor_;
 405       Real demerit = factor * dy;
 406       if (state.extremes_[d].stem_
 407           && state.extremes_[d].stem_dir_ == state.dir_
 408           && !Stem::get_beaming (state.extremes_[d].stem_, -d))
 409         demerit /= 5;
 410
 411       demerit *= exp (state.dir_ * d * slope
 412                       * state.parameters_.edge_slope_exponent_);
 413
 414       score_ += demerit;
 415 #if DEBUG_SLUR_SCORING
 416       score_card_ += to_string ("E%.2f", demerit);
 417 #endif
 418     }
 419   while (flip (&d) != LEFT);
 420 }
 421
 422 void
 423 Slur_configuration ::score_slopes (Slur_score_state const &state)
 424 {
 425   Real dy = state.musical_dy_;
 426   Offset slur_dz = attachment_[RIGHT] - attachment_[LEFT];
 427   Real slur_dy = slur_dz[Y_AXIS];
 428   Real demerit = 0.0;
 429
 430   demerit += max ((fabs (slur_dy / slur_dz[X_AXIS])
 431                    - state.parameters_.max_slope_), 0.0)
 432     * state.parameters_.max_slope_factor_;
 433
 434   /* 0.2: account for staffline offset. */
 435   Real max_dy = (fabs (dy) + 0.2);
 436   if (state.edge_has_beams_)
 437     max_dy += 1.0;
 438
 439   if (!state.is_broken_)
 440     demerit += state.parameters_.steeper_slope_factor_
 441       * (max (fabs (slur_dy) -max_dy, 0.0));
 442
 443   demerit += max ((fabs (slur_dy / slur_dz[X_AXIS])
 444                    - state.parameters_.max_slope_), 0.0)
 445     * state.parameters_.max_slope_factor_;
 446
 447   if (sign (dy) == 0
 448       && sign (slur_dy) != 0
 449       && !state.is_broken_)
 450     demerit += state.parameters_.non_horizontal_penalty_;
 451
 452   if (sign (dy)
 453       && !state.is_broken_
 454       && sign (slur_dy)
 455       && sign (slur_dy) != sign (dy))
 456     demerit += state.edge_has_beams_
 457       ? state.parameters_.same_slope_penalty_ / 10
 458       : state.parameters_.same_slope_penalty_;
 459
 460 #if DEBUG_SLUR_SCORING
 461   score_card_ += to_string ("S%.2f", demerit);
 462 #endif
 463   score_ += demerit;
 464 }
 465
 466 void
 467 Slur_configuration::score (Slur_score_state const &state)
 468 {
 469   score_extra_encompass (state);
 470   score_slopes (state);
 471   score_edges (state);
 472   score_encompass (state);
 473 }