lily/mensural-ligature-engraver.cc

   1 /*
   2   mensural-ligature-engraver.cc -- implement Mensural_ligature_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2002--2008 Juergen Reuter <reuter@ipd.uka.de>,
   7   Pal Benko <benkop@freestart.hu>
   8 */
   9
  10 #include "coherent-ligature-engraver.hh"
  11 #include "font-interface.hh"
  12 #include "international.hh"
  13 #include "mensural-ligature.hh"
  14 #include "note-column.hh"
  15 #include "note-head.hh"
  16 #include "output-def.hh"
  17 #include "paper-column.hh"
  18 #include "pitch.hh"
  19 #include "rhythmic-head.hh"
  20 #include "spanner.hh"
  21 #include "staff-symbol-referencer.hh"
  22 #include "stream-event.hh"
  23 #include "warn.hh"
  24
  25 #include "translator.icc"
  26
  27 /*
  28  * TODO: accidentals are aligned with the first note;
  29  * they must appear ahead.
  30  *
  31  * TODO: prohibit ligatures having notes differing only in accidentals
  32  * (like \[ a\breve g as \])
  33  *
  34  * TODO: do something with multiple voices within a ligature.  See
  35  * for example:
  36  * Ockeghem: Missa Ecce ancilla domini, bassus part, end of Christe.
  37  *
  38  * TODO: enhance robustness: in case of an invalid ligature (e.g. the
  39  * input specifies a ligature that contains a minima), automatically
  40  * break the ligature into smaller, valid pieces.  Such a piece may be
  41  * a single note.
  42  */
  43
  44 class Mensural_ligature_engraver : public Coherent_ligature_engraver
  45 {
  46
  47 protected:
  48   virtual Spanner *create_ligature_spanner ();
  49   virtual void build_ligature (Spanner *ligature, vector<Grob_info> primitives);
  50   DECLARE_TRANSLATOR_LISTENER (ligature);
  51
  52 public:
  53   TRANSLATOR_DECLARATIONS (Mensural_ligature_engraver);
  54
  55 private:
  56   void transform_heads (vector<Grob_info> primitives);
  57   void propagate_properties (Spanner *ligature, vector<Grob_info> primitives);
  58   void fold_up_primitives (vector<Grob_info> primitives);
  59 };
  60
  61 IMPLEMENT_TRANSLATOR_LISTENER (Mensural_ligature_engraver, ligature);
  62 void
  63 Mensural_ligature_engraver::listen_ligature (Stream_event *ev)
  64 {
  65   Ligature_engraver::listen_ligature (ev);
  66 }
  67
  68 Mensural_ligature_engraver::Mensural_ligature_engraver ()
  69 {
  70   brew_ligature_primitive_proc =
  71     Mensural_ligature::brew_ligature_primitive_proc;
  72 }
  73
  74 Spanner *
  75 Mensural_ligature_engraver::create_ligature_spanner ()
  76 {
  77   return make_spanner ("MensuralLigature", SCM_EOL);
  78 }
  79
  80 void
  81 Mensural_ligature_engraver::transform_heads (vector<Grob_info> primitives)
  82 {
  83   if (primitives.size () < 2)
  84     {
  85       warning (_ ("ligature with less than 2 heads -> skipping"));
  86       return;
  87     }
  88   int prev_pitch = 0;
  89   bool at_beginning = true;
  90
  91   // needed so that we can check whether
  92   // the previous note can be turned into a flexa
  93   bool prev_brevis_shape = false;
  94
  95   bool prev_semibrevis = false;
  96   Item *prev_primitive = NULL;
  97
  98   for (vsize i = 0, s = primitives.size (); i < s; i++)
  99     {
 100       Grob_info info = primitives[i];
 101       Item *primitive = dynamic_cast<Item *> (info.grob ());
 102       int duration_log = Rhythmic_head::duration_log (primitive);
 103
 104       Stream_event *nr = info.event_cause ();
 105
 106       /*
 107         ugh. why not simply check for pitch?
 108       */
 109       if (!nr->in_event_class ("note-event"))
 110         {
 111           nr->origin ()->warning
 112             (_ ("cannot determine pitch of ligature primitive -> skipping"));
 113           at_beginning = true;
 114           continue;
 115         }
 116
 117       int pitch = unsmob_pitch (nr->get_property ("pitch"))->steps ();
 118       int delta_pitch = 0;
 119
 120       if (at_beginning)
 121         {
 122           if (i == s - 1)
 123             {
 124               // we can get here after invalid input
 125               nr->origin ()->warning
 126                 (_ ("single note ligature - skipping"));
 127               break;
 128             }
 129           prev_semibrevis = prev_brevis_shape = false;
 130           prev_primitive = NULL;
 131         }
 132       else
 133         {
 134           delta_pitch = pitch - prev_pitch;
 135           if (delta_pitch == 0)
 136             {
 137               nr->origin ()->warning
 138                 (_ ("prime interval within ligature -> skipping"));
 139               at_beginning = true;
 140               primitive->set_property ("primitive",
 141                                        scm_from_int (MLP_NONE));
 142               continue;
 143             }
 144         }
 145
 146       if (duration_log < -3 // is this possible at all???
 147           || duration_log > 0)
 148         {
 149           nr->origin ()->warning
 150             (_ ("mensural ligature: duration none of Mx, L, B, S -> skipping"));
 151           primitive->set_property ("primitive",
 152                                    scm_from_int (MLP_NONE));
 153           at_beginning = true;
 154           continue;
 155         }
 156
 157       // apply_transition replacement begins
 158       bool general_case = true;
 159
 160       // first check special cases
 161       // 1. beginning
 162       if (at_beginning)
 163         {
 164           // a. semibreves
 165           if (duration_log == 0)
 166             {
 167               primitive->set_property ("primitive",
 168                                        scm_from_int (MLP_UP | MLP_BREVIS));
 169               prev_semibrevis = prev_brevis_shape = true;
 170               general_case = false;
 171             }
 172           // b. descendens longa or brevis
 173           else if (i < s - 1
 174                    && (unsmob_pitch (primitives[i + 1].event_cause ()
 175                                      ->get_property ("pitch"))->steps () < pitch)
 176                    && duration_log > -3)
 177             {
 178               int left_stem = duration_log == -1 ? MLP_DOWN : 0;
 179
 180               primitive->set_property ("primitive",
 181                                        scm_from_int (left_stem | MLP_BREVIS));
 182               prev_brevis_shape = true;
 183               prev_semibrevis = general_case = false;
 184             }
 185         }
 186       // 2. initial semibrevis must be followed by another one
 187       else if (prev_semibrevis)
 188         {
 189           prev_semibrevis = false;
 190           if (duration_log == 0)
 191             {
 192               primitive->set_property ("primitive", scm_from_int (MLP_BREVIS));
 193               general_case = false;
 194             }
 195           else
 196             {
 197               nr->origin ()->warning
 198                 (_ ("semibrevis must be followed by another one -> skipping"));
 199               primitive->set_property ("primitive",
 200                                        scm_from_int (MLP_NONE));
 201               at_beginning = true;
 202               continue;
 203             }
 204         }
 205       // 3. semibreves are otherwise not allowed
 206       else if (duration_log == 0)
 207         {
 208           nr->origin ()->warning
 209             (_ ("semibreves can only appear at the beginning of a ligature,\n"
 210                 "and there may be only zero or two of them"));
 211           primitive->set_property ("primitive",
 212                                    scm_from_int (MLP_NONE));
 213           at_beginning = true;
 214           continue;
 215         }
 216       // 4. end, descendens
 217       else if (i == s - 1 && delta_pitch < 0)
 218         {
 219           // brevis; previous note must be turned into flexa
 220           if (duration_log == -1)
 221             {
 222               if (prev_brevis_shape)
 223                 {
 224                   prev_primitive->set_property
 225                     ("primitive",
 226                      scm_from_int
 227                      (MLP_FLEXA
 228                       | (scm_to_int (prev_primitive->get_property ("primitive"))
 229                          & MLP_DOWN)));
 230                   primitive->set_property ("primitive", scm_from_int (MLP_NONE));
 231                   break; // no more notes, no join
 232                 }
 233               else
 234                 {
 235                   nr->origin ()->warning
 236                     (_ ("invalid ligatura ending:\n"
 237                         "when the last note is a descending brevis,\n"
 238                         "the penultimate note must be another one,\n"
 239                         "or the ligatura must be LB or SSB"));
 240                   primitive->set_property ("primitive", scm_from_int (MLP_NONE));
 241                   break;
 242                 }
 243             }
 244           // longa
 245           else if (duration_log == -2)
 246             {
 247               primitive->set_property ("primitive", scm_from_int (MLP_BREVIS));
 248               general_case = false;
 249             }
 250           // else maxima; fall through regular case below
 251         }
 252
 253       if (general_case)
 254         {
 255           static int const shape[3] = {MLP_MAXIMA, MLP_LONGA, MLP_BREVIS};
 256
 257           primitive->set_property ("primitive",
 258                                    scm_from_int (shape[duration_log + 3]));
 259           prev_brevis_shape = duration_log == -1;
 260         }
 261
 262       // join_primitives replacement
 263       if (!at_beginning)
 264         {
 265           /*
 266             if the previous note is longa-shaped and this note is lower,
 267             then the joining line may hide the stem, so it is made longer
 268             to serve as stem as well
 269           */
 270           if (delta_pitch < 0
 271               && (scm_to_int (prev_primitive->get_property ("primitive"))
 272                   & MLP_LONGA))
 273             {
 274               delta_pitch -= 6;
 275               // instead of number 6
 276               // the legth of the longa stem should be queried something like
 277               // Font_interface::get_default_font (ligature)->find_by_name
 278               //  ("noteheads.sM2mensural").extent (Y_AXIS).length ()
 279             }
 280           prev_primitive->set_property ("join-right-amount",
 281                                         scm_from_int (delta_pitch));
 282           // perhaps set add-join as well
 283         }
 284       at_beginning = false;
 285       prev_primitive = primitive;
 286       prev_pitch = pitch;
 287       // apply_transition replacement ends
 288     }
 289 }
 290
 291 /*
 292  * A MensuralLigature grob consists of a bunch of NoteHead grobs that
 293  * are glued together.  It (a) does not make sense to change
 294  * properties like thickness or flexa-width from one head to the next
 295  * within a ligature (this would totally screw up alignment), and (b)
 296  * some of these properties (like flexa-width) are specific to
 297  * e.g. the MensuralLigature (as in contrast to e.g. LigatureBracket),
 298  * and therefore should not be handled in the NoteHead code (which is
 299  * also used by LigatureBracket).  Therefore, we let the user control
 300  * these properties via the concrete Ligature grob (like
 301  * MensuralLigature) and then copy these properties as necessary to
 302  * each of the NoteHead grobs.  This is what
 303  * propagate_properties () does.
 304  */
 305 void
 306 Mensural_ligature_engraver::propagate_properties (Spanner *ligature,
 307                                                   vector<Grob_info> primitives)
 308 {
 309   Real thickness
 310     = robust_scm2double (ligature->get_property ("thickness"), 1.4);
 311   thickness
 312     *= ligature->layout ()->get_dimension (ly_symbol2scm ("line-thickness"));
 313
 314   Real head_width
 315     = Font_interface::get_default_font (ligature)->
 316     find_by_name ("noteheads.sM1mensural").extent (X_AXIS).length ();
 317   Real flexa_width
 318     = robust_scm2double (ligature->get_property ("flexa-width"), 2);
 319   Real maxima_head_width
 320     = Font_interface::get_default_font (ligature)->
 321     find_by_name ("noteheads.sM1neomensural").extent (X_AXIS).length ();
 322
 323   flexa_width *= Staff_symbol_referencer::staff_space (ligature);
 324
 325   Real half_flexa_width = 0.5 * (flexa_width + thickness);
 326
 327   for (vsize i = 0; i < primitives.size (); i++)
 328     {
 329       Item *primitive = dynamic_cast<Item *> (primitives[i].grob ());
 330       int output = scm_to_int (primitive->get_property ("primitive"));
 331       primitive->set_property ("thickness",
 332                                scm_from_double (thickness));
 333
 334       switch (output & MLP_ANY)
 335         {
 336         case MLP_NONE:
 337           primitive->set_property ("head-width",
 338                                    scm_from_double (half_flexa_width));
 339           break;
 340         case MLP_BREVIS:
 341         case MLP_LONGA:
 342           primitive->set_property ("head-width",
 343                                    scm_from_double (head_width));
 344           break;
 345         case MLP_MAXIMA:
 346           primitive->set_property ("head-width",
 347                                    scm_from_double (maxima_head_width));
 348           break;
 349         case MLP_FLEXA:
 350           primitive->set_property ("head-width",
 351                                    scm_from_double (half_flexa_width));
 352           primitive->set_property ("flexa-width",
 353                                    scm_from_double (flexa_width));
 354           break;
 355         default:
 356           programming_error (_ ("unexpected case fall-through"));
 357           break;
 358         }
 359     }
 360 }
 361
 362 void
 363 Mensural_ligature_engraver::fold_up_primitives (vector<Grob_info> primitives)
 364 {
 365   Item *first = 0;
 366   Real distance = 0.0;
 367   Real dot_shift = 0.0;
 368   for (vsize i = 0; i < primitives.size (); i++)
 369     {
 370       Item *current = dynamic_cast<Item *> (primitives[i].grob ());
 371       if (i == 0)
 372         {
 373           first = current;
 374           dot_shift = 1.5 * Staff_symbol_referencer::staff_space (first);
 375         }
 376
 377       move_related_items_to_column (current, first->get_column (),
 378                                     distance);
 379
 380       distance
 381         += scm_to_double (current->get_property ("head-width"))
 382         - scm_to_double (current->get_property ("thickness"));
 383
 384       if (Rhythmic_head::dot_count (current) > 0)
 385         // Move dots above/behind the ligature.
 386         {
 387           if (i + 1 < primitives.size ())
 388             // dot in the midst => move above head
 389             {
 390               // FIXME: Amount of vertical dot-shift should depend on
 391               // pitch.
 392               //
 393               // FIXME: dot placement is horizontally slightly off.
 394               Rhythmic_head::get_dots (current)->translate_axis (dot_shift, Y_AXIS);
 395             }
 396           else
 397             // trailing dot => move behind head
 398             {
 399               double head_width =
 400                 scm_to_double (current->get_property ("head-width"));
 401               Rhythmic_head::get_dots (current)->
 402                 translate_axis (head_width, X_AXIS);
 403             }
 404         }
 405     }
 406 }
 407
 408 void
 409 Mensural_ligature_engraver::build_ligature (Spanner *ligature,
 410                                             vector<Grob_info> primitives)
 411 {
 412   transform_heads (primitives);
 413   propagate_properties (ligature, primitives);
 414   fold_up_primitives (primitives);
 415 }
 416
 417 ADD_ACKNOWLEDGER (Mensural_ligature_engraver, rest);
 418 ADD_ACKNOWLEDGER (Mensural_ligature_engraver, note_head);
 419
 420 ADD_TRANSLATOR (Mensural_ligature_engraver,
 421                 /* doc */
 422                 "Handle @code{Mensural_ligature_events} by glueing special"
 423                 " ligature heads together.",
 424
 425                 /* create */
 426                 "MensuralLigature ",
 427
 428                 /* read */
 429                 "",
 430
 431                 /* write */
 432                 ""
 433                 );