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 "pointer-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                                     Array<Offset> const &avoid
 101                                     )
 102 {
 103   Offset dz = attachment_[RIGHT]- attachment_[LEFT];;
 104   Offset dz_unit = dz;
 105   dz_unit *= 1 / dz.length ();
 106   Offset dz_perp = dz_unit * Offset (0, 1);
 107
 108   Real indent, height;
 109   get_slur_indent_height (&indent, &height, dz.length (), h_inf, r_0);
 110
 111   Real len = dz.length ();
 112
 113   /* This condition,
 114
 115   len^2 > 4h^2 +  3 (i + 1/3len)^2  - 1/3 len^2
 116
 117   is equivalent to:
 118
 119   |bez' (0)| < | bez' (.5)|
 120
 121   when (control2 - control1) has the same direction as
 122   (control3 - control0).  */
 123
 124   Real max_indent = len / 3.1;
 125   indent = min (indent, max_indent);
 126
 127   Real a1 = sqr (len) / 3.0;
 128   Real a2 = 0.75 * sqr (indent + len / 3.0);
 129   Real max_h = a1 - a2;
 130
 131   if (max_h < 0)
 132     {
 133       programming_error ("slur indent too small");
 134       max_h = len / 3.0;
 135     }
 136   else
 137     {
 138       max_h = sqrt (max_h);
 139     }
 140
 141   Real eccentricity = robust_scm2double (state.slur_->get_property ("eccentricity"), 0);
 142
 143   Real x1 = (eccentricity + indent);
 144   Real x2 = (eccentricity - indent);
 145
 146   Bezier curve;
 147   curve.control_[0] = attachment_[LEFT];
 148   curve.control_[1] = attachment_[LEFT] + dz_perp * height * state.dir_
 149     + dz_unit * x1;
 150   curve.control_[2] = attachment_[RIGHT] + dz_perp * height * state.dir_
 151     + dz_unit * x2;
 152   curve.control_[3] = attachment_[RIGHT];
 153
 154   Real ff = fit_factor (dz_unit, dz_perp, curve, state.dir_, avoid);
 155
 156   height = max (height, min (height * ff, max_h));
 157
 158   curve.control_[0] = attachment_[LEFT];
 159   curve.control_[1] = attachment_[LEFT] + dz_perp * height * state.dir_
 160     + dz_unit * x1;
 161   curve.control_[2] = attachment_[RIGHT] + dz_perp * height * state.dir_
 162     + dz_unit * x2;
 163   curve.control_[3] = attachment_[RIGHT];
 164
 165   curve_ = avoid_staff_line (state, curve);
 166   height_ = height;
 167 }
 168
 169 Slur_configuration::Slur_configuration ()
 170 {
 171   score_ = 0.0;
 172   index_ = -1;
 173 };
 174
 175 void
 176 Slur_configuration::score_encompass (Slur_score_state const &state)
 177 {
 178   Bezier const &bez (curve_);
 179   Real demerit = 0.0;
 180
 181   /*
 182     Distances for heads that are between slur and line between
 183     attachment points.
 184   */
 185   Array<Real> convex_head_distances;
 186   for (int j = 0; j < state.encompass_infos_.size (); j++)
 187     {
 188       Real x = state.encompass_infos_[j].x_;
 189
 190       bool l_edge = j == 0;
 191       bool r_edge = j == state.encompass_infos_.size () - 1;
 192       bool edge = l_edge || r_edge;
 193
 194       if (! (x < attachment_[RIGHT][X_AXIS]
 195              && x > attachment_[LEFT][X_AXIS]))
 196         continue;
 197
 198       Real y = bez.get_other_coordinate (X_AXIS, x);
 199       if (!edge)
 200         {
 201           Real head_dy = (y - state.encompass_infos_[j].head_);
 202           if (state.dir_ * head_dy < 0)
 203             {
 204               demerit += state.parameters_.head_encompass_penalty_;
 205               convex_head_distances.push (0.0);
 206             }
 207           else
 208             {
 209               Real hd = (head_dy)
 210                 ? (1 / fabs (head_dy) - 1 / state.parameters_.free_head_distance_)
 211                 : state.parameters_.head_encompass_penalty_;
 212               hd = min (max (hd, 0.0), state.parameters_.head_encompass_penalty_);
 213
 214               demerit += hd;
 215             }
 216
 217           Real line_y = linear_interpolate (x,
 218                                             attachment_[RIGHT][X_AXIS],
 219                                             attachment_[LEFT][X_AXIS],
 220                                             attachment_[RIGHT][Y_AXIS],
 221                                             attachment_[LEFT][Y_AXIS]);
 222
 223           if (1) // state.dir_ * state.encompass_infos_[j].get_point (state.dir_) > state.dir_ *line_y )
 224             {
 225
 226               Real closest
 227                 = state.dir_ * max (state.dir_ * state.encompass_infos_[j].get_point (state.dir_), state.dir_ * line_y);
 228               Real d = fabs (closest - y);
 229
 230               convex_head_distances.push (d);
 231             }
 232         }
 233
 234       if (state.dir_ * (y - state.encompass_infos_[j].stem_) < 0)
 235         {
 236           Real stem_dem = state.parameters_.stem_encompass_penalty_;
 237           if ((l_edge && state.dir_ == UP)
 238               || (r_edge && state.dir_ == DOWN))
 239             stem_dem /= 5;
 240
 241           demerit += stem_dem;
 242         }
 243       else if (!edge)
 244         {
 245           Interval ext;
 246           ext.add_point (state.encompass_infos_[j].stem_);
 247           ext.add_point (state.encompass_infos_[j].head_);
 248
 249           // ?
 250           demerit += -state.parameters_.closeness_factor_
 251             * min (state.dir_
 252                    * (y - (ext[state.dir_] + state.dir_ * state.parameters_.free_head_distance_)), 0.0)
 253             / state.encompass_infos_.size ();
 254         }
 255     }
 256
 257   Real variance_penalty = 0.0;
 258
 259   if (convex_head_distances.size ())
 260     {
 261       Real avg_distance = 0.0;
 262       Real min_dist = infinity_f;
 263       for (int j = 0; j < convex_head_distances.size (); j++)
 264         {
 265           min_dist = min (min_dist, convex_head_distances[j]);
 266           avg_distance += convex_head_distances[j];
 267         }
 268
 269       /*
 270         For slurs over 3 or 4 heads, the average distance is not a
 271         good normalizer.
 272       */
 273       Real n = convex_head_distances.size ();
 274       if (n <= 2)
 275         {
 276           Real fact = 1.0;
 277           avg_distance += height_ * fact;
 278           n += fact;
 279         }
 280
 281       /*
 282         TODO: maybe it's better to use (avgdist - mindist)*factor
 283         as penalty.
 284       */
 285       avg_distance /= n;
 286       variance_penalty = state.parameters_.head_slur_distance_max_ratio_;
 287       if (min_dist > 0.0)
 288         variance_penalty
 289           = min ((avg_distance / (min_dist + state.parameters_.absolute_closeness_measure_) - 1.0),  variance_penalty);
 290
 291       variance_penalty = max (variance_penalty, 0.0);
 292       variance_penalty *= state.parameters_.head_slur_distance_factor_;
 293     }
 294
 295 #if DEBUG_SLUR_SCORING
 296   score_card_ += to_string ("C%.2f", demerit);
 297   score_card_ += to_string ("D%.2f", variance_penalty);
 298 #endif
 299
 300   score_ += demerit + variance_penalty;
 301 }
 302
 303 void
 304 Slur_configuration::score_extra_encompass (Slur_score_state const &state)
 305 {
 306   Real demerit = 0.0;
 307   for (int j = 0; j < state.extra_encompass_infos_.size (); j++)
 308     {
 309       Drul_array<Offset> attachment = attachment_;
 310       Interval slur_wid (attachment[LEFT][X_AXIS], attachment[RIGHT][X_AXIS]);
 311
 312       /*
 313         to prevent numerical inaccuracies in
 314         Bezier::get_other_coordinate ().
 315       */
 316       Direction d = LEFT;
 317       bool found = false;
 318       Real y = 0.0;
 319
 320       do
 321         {
 322           /*
 323             We need to check for the bound explicitly, since the
 324             slur-ending can be almost vertical, making the Y
 325             coordinate a bad approximation of the object-slur
 326             distance.
 327           */
 328           Item *as_item = dynamic_cast<Item *> (state.extra_encompass_infos_[j].grob_);
 329           if ((as_item
 330                && as_item->get_column ()
 331                == state.extremes_[d].bound_->get_column ())
 332               || state.extra_encompass_infos_[j].extents_[X_AXIS].contains (attachment[d][X_AXIS]))
 333             {
 334               y = attachment[d][Y_AXIS];
 335               found = true;
 336             }
 337         }
 338       while (flip (&d) != LEFT);
 339
 340       if (!found)
 341         {
 342           Real x = state.extra_encompass_infos_[j].extents_[X_AXIS]
 343             .linear_combination (state.extra_encompass_infos_[j].idx_);
 344
 345           if (!slur_wid.contains (x))
 346             continue;
 347
 348           y = curve_.get_other_coordinate (X_AXIS, x);
 349         }
 350
 351       Real dist = state.extra_encompass_infos_[j].extents_[Y_AXIS].distance (y);
 352       demerit
 353         += fabs (max (0.0, (state.parameters_.extra_encompass_free_distance_ - dist)))
 354         / state.parameters_.extra_encompass_free_distance_
 355         * state.extra_encompass_infos_[j].penalty_;
 356     }
 357 #if DEBUG_SLUR_SCORING
 358   score_card_ += to_string ("X%.2f", demerit);
 359 #endif
 360   score_ += demerit;
 361 }
 362
 363 void
 364 Slur_configuration::score_edges (Slur_score_state const &state)
 365 {
 366   Direction d = LEFT;
 367   Offset dz = attachment_[RIGHT]
 368     - attachment_[LEFT];
 369   Real slope = dz[Y_AXIS] / dz[X_AXIS];
 370   do
 371     {
 372       Real y = attachment_[d][Y_AXIS];
 373       Real dy = fabs (y - state.base_attachments_[d][Y_AXIS]);
 374
 375       Real factor = state.parameters_.edge_attraction_factor_;
 376       Real demerit = factor * dy;
 377       if (state.extremes_[d].stem_
 378           && state.extremes_[d].stem_dir_ == state.dir_
 379           && !Stem::get_beaming (state.extremes_[d].stem_, -d))
 380         demerit /= 5;
 381
 382       demerit *= exp (state.dir_ * d * slope
 383                       * state.parameters_.edge_slope_exponent_);
 384
 385       score_ += demerit;
 386 #if DEBUG_SLUR_SCORING
 387       score_card_ += to_string ("E%.2f", demerit);
 388 #endif
 389     }
 390   while (flip (&d) != LEFT);
 391 }
 392
 393 void
 394 Slur_configuration ::score_slopes (Slur_score_state const &state)
 395 {
 396   Real dy = state.musical_dy_;
 397   Offset slur_dz = attachment_[RIGHT] - attachment_[LEFT];
 398   Real slur_dy = slur_dz[Y_AXIS];
 399   Real demerit = 0.0;
 400
 401   demerit += max ((fabs (slur_dy / slur_dz[X_AXIS])
 402                    - state.parameters_.max_slope_), 0.0)
 403     * state.parameters_.max_slope_factor_;
 404
 405   /* 0.2: account for staffline offset. */
 406   Real max_dy = (fabs (dy) + 0.2);
 407   if (state.edge_has_beams_)
 408     max_dy += 1.0;
 409
 410   if (!state.is_broken_)
 411     demerit += state.parameters_.steeper_slope_factor_
 412       * (max (fabs (slur_dy) -max_dy, 0.0));
 413
 414   demerit += max ((fabs (slur_dy / slur_dz[X_AXIS])
 415                    - state.parameters_.max_slope_), 0.0)
 416     * state.parameters_.max_slope_factor_;
 417
 418   if (sign (dy) == 0
 419       && sign (slur_dy) != 0
 420       && !state.is_broken_)
 421     demerit += state.parameters_.non_horizontal_penalty_;
 422
 423   if (sign (dy)
 424       && !state.is_broken_
 425       && sign (slur_dy)
 426       && sign (slur_dy) != sign (dy))
 427     demerit += state.edge_has_beams_
 428       ? state.parameters_.same_slope_penalty_ / 10
 429       : state.parameters_.same_slope_penalty_;
 430
 431 #if DEBUG_SLUR_SCORING
 432   score_card_ += to_string ("S%.2f", demerit);
 433 #endif
 434   score_ += demerit;
 435 }
 436
 437 void
 438 Slur_configuration::score (Slur_score_state const &state)
 439 {
 440   score_extra_encompass (state);
 441   score_slopes (state);
 442   score_edges (state);
 443   score_encompass (state);
 444 }