lily/mensural-ligature-engraver.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 2002--2011 Juergen Reuter <reuter@ipd.uka.de>,
   5   Pal Benko <benkop@freestart.hu>
   6
   7   LilyPond is free software: you can redistribute it and/or modify
   8   it under the terms of the GNU General Public License as published by
   9   the Free Software Foundation, either version 3 of the License, or
  10   (at your option) any later version.
  11
  12   LilyPond is distributed in the hope that it will be useful,
  13   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15   GNU General Public License for more details.
  16
  17   You should have received a copy of the GNU General Public License
  18   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "coherent-ligature-engraver.hh"
  22 #include "font-interface.hh"
  23 #include "international.hh"
  24 #include "mensural-ligature.hh"
  25 #include "note-column.hh"
  26 #include "note-head.hh"
  27 #include "output-def.hh"
  28 #include "paper-column.hh"
  29 #include "pitch.hh"
  30 #include "rhythmic-head.hh"
  31 #include "spanner.hh"
  32 #include "staff-symbol-referencer.hh"
  33 #include "stream-event.hh"
  34 #include "warn.hh"
  35
  36 #include "translator.icc"
  37
  38 /*
  39  * TODO: accidentals are aligned with the first note;
  40  * they must appear ahead.
  41  *
  42  * TODO: prohibit ligatures having notes differing only in accidentals
  43  * (like \[ a\breve g as \])
  44  *
  45  * TODO: do something with multiple voices within a ligature.  See
  46  * for example:
  47  * Ockeghem: Missa Ecce ancilla domini, bassus part, end of Christe.
  48  *
  49  * TODO: enhance robustness: in case of an invalid ligature (e.g. the
  50  * input specifies a ligature that contains a minima), automatically
  51  * break the ligature into smaller, valid pieces.  Such a piece may be
  52  * a single note.
  53  */
  54
  55 class Mensural_ligature_engraver : public Coherent_ligature_engraver
  56 {
  57
  58 protected:
  59   virtual Spanner *create_ligature_spanner ();
  60   virtual void build_ligature (Spanner *ligature, vector<Grob_info> primitives);
  61   DECLARE_TRANSLATOR_LISTENER (ligature);
  62
  63 public:
  64   TRANSLATOR_DECLARATIONS (Mensural_ligature_engraver);
  65
  66 private:
  67   void transform_heads (vector<Grob_info> primitives);
  68   void propagate_properties (Spanner *ligature, vector<Grob_info> primitives);
  69   void fold_up_primitives (vector<Grob_info> primitives);
  70 };
  71
  72 IMPLEMENT_TRANSLATOR_LISTENER (Mensural_ligature_engraver, ligature);
  73 void
  74 Mensural_ligature_engraver::listen_ligature (Stream_event *ev)
  75 {
  76   Ligature_engraver::listen_ligature (ev);
  77 }
  78
  79 Mensural_ligature_engraver::Mensural_ligature_engraver ()
  80 {
  81   brew_ligature_primitive_proc =
  82     Mensural_ligature::brew_ligature_primitive_proc;
  83 }
  84
  85 Spanner *
  86 Mensural_ligature_engraver::create_ligature_spanner ()
  87 {
  88   return make_spanner ("MensuralLigature", SCM_EOL);
  89 }
  90
  91 void
  92 Mensural_ligature_engraver::transform_heads (vector<Grob_info> primitives)
  93 {
  94   if (primitives.size () < 2)
  95     {
  96       warning (_ ("ligature with less than 2 heads -> skipping"));
  97       return;
  98     }
  99   int prev_pitch = 0;
 100   bool at_beginning = true;
 101
 102   // needed so that we can check whether
 103   // the previous note can be turned into a flexa
 104   bool prev_brevis_shape = false;
 105
 106   bool prev_semibrevis = false;
 107   Item *prev_primitive = NULL;
 108
 109   for (vsize i = 0, s = primitives.size (); i < s; i++)
 110     {
 111       Grob_info info = primitives[i];
 112       Item *primitive = dynamic_cast<Item *> (info.grob ());
 113       int duration_log = Rhythmic_head::duration_log (primitive);
 114
 115       Stream_event *nr = info.event_cause ();
 116
 117       /*
 118         ugh. why not simply check for pitch?
 119       */
 120       if (!nr->in_event_class ("note-event"))
 121         {
 122           nr->origin ()->warning
 123             (_ ("cannot determine pitch of ligature primitive -> skipping"));
 124           at_beginning = true;
 125           continue;
 126         }
 127
 128       int pitch = unsmob_pitch (nr->get_property ("pitch"))->steps ();
 129       int prim = 0;
 130
 131       if (at_beginning)
 132         {
 133           if (i == s - 1)
 134             {
 135               // we can get here after invalid input
 136               nr->origin ()->warning
 137                 (_ ("single note ligature - skipping"));
 138               break;
 139             }
 140           prev_semibrevis = prev_brevis_shape = false;
 141           prev_primitive = NULL;
 142         }
 143       else
 144         {
 145           if (pitch == prev_pitch)
 146             {
 147               nr->origin ()->warning
 148                 (_ ("prime interval within ligature -> skipping"));
 149               at_beginning = true;
 150               prim = MLP_NONE;
 151               continue;
 152             }
 153         }
 154
 155       if (duration_log < -3 // is this possible at all???
 156           || duration_log > 0)
 157         {
 158           nr->origin ()->warning
 159             (_ ("mensural ligature: duration none of Mx, L, B, S -> skipping"));
 160           prim = MLP_NONE;
 161           at_beginning = true;
 162           continue;
 163         }
 164
 165       bool general_case = true;
 166       bool make_flexa = false;
 167       bool allow_flexa = true;
 168
 169       // first check special cases
 170       // 1. beginning
 171       if (at_beginning)
 172         {
 173           // a. semibreves
 174           if (duration_log == 0)
 175             {
 176               prim = MLP_UP | MLP_BREVIS;
 177               general_case = false;
 178             }
 179           // b. descendens longa or brevis
 180           else if (i < s - 1
 181                    && (unsmob_pitch (primitives[i + 1].event_cause ()
 182                                      ->get_property ("pitch"))->steps () < pitch)
 183                    && duration_log > -3)
 184             {
 185               int left_stem = duration_log == -1 ? MLP_DOWN : 0;
 186               prim = left_stem | MLP_BREVIS;
 187               general_case = false;
 188             }
 189         }
 190       // 2. initial semibrevis must be followed by another one
 191       else if (prev_semibrevis)
 192         {
 193           prev_semibrevis = false;
 194           if (duration_log == 0)
 195             {
 196               prim = MLP_BREVIS;
 197               general_case = false;
 198             }
 199           else
 200             {
 201               nr->origin ()->warning
 202                 (_ ("semibrevis must be followed by another one -> skipping"));
 203               prim = MLP_NONE;
 204               at_beginning = true;
 205               continue;
 206             }
 207         }
 208       // 3. semibreves are otherwise not allowed
 209       else if (duration_log == 0)
 210         {
 211           nr->origin ()->warning
 212             (_ ("semibreves can only appear at the beginning of a ligature,\n"
 213                 "and there may be only zero or two of them"));
 214           prim = MLP_NONE;
 215           at_beginning = true;
 216           continue;
 217         }
 218       // 4. end, descendens
 219       else if (i == s - 1 && pitch < prev_pitch)
 220         {
 221           // brevis; previous note must be turned into flexa
 222           if (duration_log == -1)
 223             {
 224               if (prev_brevis_shape)
 225                 {
 226                   make_flexa = true;
 227                   general_case = false;
 228                 }
 229               else
 230                 {
 231                   nr->origin ()->warning
 232                     (_ ("invalid ligatura ending:\n"
 233                         "when the last note is a descending brevis,\n"
 234                         "the penultimate note must be another one,\n"
 235                         "or the ligatura must be LB or SSB"));
 236                   prim = MLP_NONE;
 237                   break;
 238                 }
 239             }
 240           // longa
 241           else if (duration_log == -2)
 242             {
 243               prim = MLP_BREVIS;
 244               general_case = allow_flexa = false;
 245             }
 246           // else maxima; fall through to regular case below
 247         }
 248
 249       if (allow_flexa
 250           && to_boolean (primitive->get_property ("ligature-flexa")))
 251         {
 252           /*
 253             flexa requested, check whether allowed:
 254             - there should be a previous note
 255             - both of the notes must be of brevis shape
 256               (i.e. can't be maxima or flexa;
 257               longa is forbidden as well - it's nonexistent anyway)
 258             - no compulsory flexa for the next note,
 259               i.e. it's not an ultimate descending breve
 260           */
 261           make_flexa = !at_beginning && prev_brevis_shape && duration_log > -2;
 262           if (make_flexa && i == s - 2)
 263             {
 264               /*
 265                 check last condition: look ahead to next note
 266               */
 267               Grob_info next_info = primitives[i + 1];
 268               Item *next_primitive = dynamic_cast<Item *> (next_info.grob ());
 269               if (Rhythmic_head::duration_log (next_primitive) == -1)
 270                 {
 271                   /*
 272                     breve: check whether descending
 273                   */
 274                   int const next_pitch = unsmob_pitch
 275                     (next_info.event_cause ()->get_property ("pitch"))->steps ();
 276                   if (next_pitch < pitch)
 277                     /*
 278                       sorry, forbidden
 279                     */
 280                     make_flexa = false;
 281                 }
 282             }
 283         }
 284
 285       if (general_case)
 286         {
 287           static int const shape[3] = {MLP_MAXIMA, MLP_LONGA, MLP_BREVIS};
 288
 289           prim = shape[duration_log + 3];
 290         }
 291
 292       if (make_flexa)
 293         {
 294           /*
 295             turn the note with the previous one into a flexa
 296           */
 297           prev_primitive->set_property
 298             ("primitive",
 299              scm_from_int
 300              (MLP_FLEXA_BEGIN
 301               | (scm_to_int (prev_primitive->get_property ("primitive"))
 302                  & MLP_STEM)));
 303           prev_primitive->set_property
 304             ("flexa-interval", scm_from_int (pitch - prev_pitch));
 305           prim = MLP_FLEXA_END;
 306           primitive->set_property
 307             ("flexa-interval", scm_from_int (pitch - prev_pitch));
 308         }
 309
 310       // join_primitives replacement
 311       if (!(at_beginning || make_flexa))
 312         prev_primitive->set_property ("add-join", ly_bool2scm (true));
 313
 314       at_beginning = false;
 315       prev_primitive = primitive;
 316       prev_pitch = pitch;
 317       primitive->set_property ("primitive", scm_from_int (prim));
 318       prev_brevis_shape = (prim & MLP_BREVIS) != 0;
 319       prev_semibrevis = (prim & MLP_UP) != 0;
 320     }
 321 }
 322
 323 /*
 324  * A MensuralLigature grob consists of a bunch of NoteHead grobs that
 325  * are glued together.  It (a) does not make sense to change
 326  * properties like thickness or flexa-width from one head to the next
 327  * within a ligature (this would totally screw up alignment), and (b)
 328  * some of these properties (like flexa-width) are specific to
 329  * e.g. the MensuralLigature (as in contrast to e.g. LigatureBracket),
 330  * and therefore should not be handled in the NoteHead code (which is
 331  * also used by LigatureBracket).  Therefore, we let the user control
 332  * these properties via the concrete Ligature grob (like
 333  * MensuralLigature) and then copy these properties as necessary to
 334  * each of the NoteHead grobs.  This is what
 335  * propagate_properties () does.
 336  */
 337 void
 338 Mensural_ligature_engraver::propagate_properties (Spanner *ligature,
 339                                                   vector<Grob_info> primitives)
 340 {
 341   Real thickness
 342     = robust_scm2double (ligature->get_property ("thickness"), 1.4);
 343   thickness
 344     *= ligature->layout ()->get_dimension (ly_symbol2scm ("line-thickness"));
 345
 346   Real head_width
 347     = Font_interface::get_default_font (ligature)->
 348     find_by_name ("noteheads.sM1mensural").extent (X_AXIS).length ();
 349   Real maxima_head_width
 350     = Font_interface::get_default_font (ligature)->
 351     find_by_name ("noteheads.sM3ligmensural").extent (X_AXIS).length ();
 352
 353   Item *prev_primitive = NULL;
 354   for (vsize i = 0; i < primitives.size (); i++)
 355     {
 356       Item *primitive = dynamic_cast<Item *> (primitives[i].grob ());
 357       int output = scm_to_int (primitive->get_property ("primitive"));
 358       primitive->set_property ("thickness",
 359                                scm_from_double (thickness));
 360
 361       switch (output & MLP_ANY) {
 362       case MLP_BREVIS:
 363       case MLP_LONGA:
 364         primitive->set_property ("head-width", scm_from_double (head_width));
 365         break;
 366       case MLP_MAXIMA:
 367         primitive->set_property ("head-width",
 368                                  scm_from_double (maxima_head_width));
 369         break;
 370       case MLP_FLEXA_BEGIN:
 371         /*
 372           the next note (should be MLP_FLEXA_END) will handle this one
 373         */
 374         break;
 375       case MLP_FLEXA_END:
 376         {
 377           SCM flexa_scm = primitive->get_property ("flexa-width");
 378           Real const flexa_width = robust_scm2double (flexa_scm, 2.0);
 379           SCM head_width = scm_from_double (0.5 * (flexa_width + thickness));
 380           primitive->set_property ("head-width", head_width);
 381           prev_primitive->set_property ("head-width", head_width);
 382           prev_primitive->set_property ("flexa-width", flexa_scm);
 383         }
 384         break;
 385       default:
 386         programming_error (_ ("unexpected case fall-through"));
 387         break;
 388       }
 389
 390       prev_primitive = primitive;
 391     }
 392 }
 393
 394 void
 395 Mensural_ligature_engraver::fold_up_primitives (vector<Grob_info> primitives)
 396 {
 397   Item *first = 0;
 398   Real distance = 0.0;
 399   Real staff_space = 0.0;
 400   Real thickness = 0.0;
 401
 402   for (vsize i = 0; i < primitives.size (); i++)
 403     {
 404       Item *current = dynamic_cast<Item *> (primitives[i].grob ());
 405       if (i == 0)
 406         {
 407           first = current;
 408           staff_space = Staff_symbol_referencer::staff_space (first);
 409           thickness = scm_to_double (current->get_property ("thickness"));
 410         }
 411
 412       move_related_items_to_column (current, first->get_column (),
 413                                     distance);
 414
 415       Real head_width = scm_to_double (current->get_property ("head-width"));
 416       distance += head_width - thickness;
 417
 418       if (Rhythmic_head::dot_count (current) > 0)
 419         /*
 420           Move dots above/behind the ligature.
 421           dots should also avoid staff lines.
 422         */
 423         {
 424           Grob *dot_gr = Rhythmic_head::get_dots (current);
 425
 426           bool const on_line = Staff_symbol_referencer::on_line
 427             (current,
 428              robust_scm2int (current->get_property ("staff-position"), 0));
 429           Real vert_shift = on_line ? staff_space * 0.5 : 0.0;
 430           bool const flexa_begin =
 431             scm_to_int (current->get_property ("primitive"))
 432             & MLP_FLEXA_BEGIN;
 433
 434           if (i + 1 < primitives.size ())
 435             /*
 436               dot in the midst => avoid next note;
 437               what to avoid and where depends on
 438               being on a line or between lines
 439             */
 440             {
 441               int const delta =
 442                 scm_to_int (current->get_property ("delta-position"));
 443               if (flexa_begin)
 444                 vert_shift += delta < 0
 445                   ? staff_space : (on_line ? -2.0 : -1.0) * staff_space;
 446               else if (on_line)
 447                 {
 448                   if (0 < delta && delta < 3)
 449                     vert_shift -= staff_space;
 450                 }
 451               else if (delta == 1 || delta == -1)
 452                   vert_shift -= delta * staff_space;
 453             }
 454
 455           dot_gr->translate_axis (vert_shift, Y_AXIS);
 456
 457           /*
 458             move all dots behind head
 459           */
 460           dot_gr->translate_axis
 461             ((flexa_begin ? staff_space * 0.6 : head_width) - 2.0*thickness, X_AXIS);
 462         }
 463     }
 464 }
 465
 466 void
 467 Mensural_ligature_engraver::build_ligature (Spanner *ligature,
 468                                             vector<Grob_info> primitives)
 469 {
 470   transform_heads (primitives);
 471   propagate_properties (ligature, primitives);
 472   fold_up_primitives (primitives);
 473 }
 474
 475 ADD_ACKNOWLEDGER (Mensural_ligature_engraver, rest);
 476 ADD_ACKNOWLEDGER (Mensural_ligature_engraver, note_head);
 477
 478 ADD_TRANSLATOR (Mensural_ligature_engraver,
 479                 /* doc */
 480                 "Handle @code{Mensural_ligature_events} by glueing special"
 481                 " ligature heads together.",
 482
 483                 /* create */
 484                 "MensuralLigature ",
 485
 486                 /* read */
 487                 "",
 488
 489                 /* write */
 490                 ""
 491                 );