lily/paper-column-engraver.cc

   1 /*
   2   paper-column-engraver.cc -- implement Paper_column_engraver
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2005--2006 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "paper-column-engraver.hh"
  10 #include "system.hh"
  11 #include "item.hh"
  12 #include "paper-column.hh"
  13 #include "staff-spacing.hh"
  14 #include "note-spacing.hh"
  15 #include "pointer-group-interface.hh"
  16 #include "context.hh"
  17 #include "axis-group-interface.hh"
  18 #include "warn.hh"
  19
  20 #include "translator.icc"
  21
  22 Paper_column_engraver::Paper_column_engraver ()
  23 {
  24   last_moment_.main_part_ = Rational (-1,1);
  25   command_column_ = 0;
  26   musical_column_ = 0;
  27   breaks_ = 0;
  28   system_ = 0;
  29   first_ = true;
  30   last_breakable_column_ = 0;
  31   last_breakable_moment_ = Moment (-1);
  32 }
  33
  34 void
  35 Paper_column_engraver::finalize ()
  36 {
  37   if ((breaks_ % 8))
  38     progress_indication ("[" + to_string (breaks_) + "]");
  39
  40   if (command_column_)
  41     {
  42       command_column_->set_property ("line-break-permission", ly_symbol2scm ("allow"));
  43       system_->set_bound (RIGHT, command_column_);
  44     }
  45 }
  46
  47 void
  48 Paper_column_engraver::make_columns ()
  49 {
  50   /*
  51     ugh.
  52   */
  53   Paper_column *p1 = make_paper_column ("NonMusicalPaperColumn");
  54   Paper_column *p2 = make_paper_column ("PaperColumn");
  55   /*
  56      The columns are timestamped with now_mom () in
  57      stop_translation_timestep. Cannot happen now, because the
  58      first column is sometimes created before now_mom is initialised.
  59   */
  60
  61   set_columns (p1, p2);
  62 }
  63
  64 void
  65 Paper_column_engraver::initialize ()
  66 {
  67   system_ = dynamic_cast<System *> (unsmob_grob (get_property ("rootSystem")));
  68   make_columns ();
  69
  70   system_->set_bound (LEFT, command_column_);
  71   command_column_->set_property ("line-break-permission", ly_symbol2scm ("allow"));
  72 }
  73
  74 void
  75 Paper_column_engraver::acknowledge_item (Grob_info gi)
  76 {
  77   items_.push_back (gi.item ());
  78 }
  79
  80 void
  81 Paper_column_engraver::acknowledge_staff_spacing (Grob_info gi)
  82 {
  83   Pointer_group_interface::add_grob (command_column_,
  84                                      ly_symbol2scm ("spacing-wishes"),
  85                                      gi.grob ());
  86 }
  87 void
  88 Paper_column_engraver::acknowledge_note_spacing (Grob_info gi)
  89 {
  90   Pointer_group_interface::add_grob (musical_column_,
  91                                      ly_symbol2scm ("spacing-wishes"),
  92                                      gi.grob ());
  93 }
  94
  95 void
  96 Paper_column_engraver::set_columns (Paper_column *new_command,
  97                                     Paper_column *new_musical)
  98 {
  99   command_column_ = new_command;
 100   musical_column_ = new_musical;
 101   if (new_command)
 102     context ()->set_property ("currentCommandColumn", new_command->self_scm ());
 103
 104   if (new_musical)
 105     context ()->set_property ("currentMusicalColumn", new_musical->self_scm ());
 106
 107   system_->add_column (command_column_);
 108   system_->add_column (musical_column_);
 109 }
 110
 111 bool
 112 Paper_column_engraver::try_music (Music *m)
 113 {
 114   break_events_.push_back (m);
 115
 116   return true;
 117 }
 118
 119 void
 120 Paper_column_engraver::process_music ()
 121 {
 122   for (vsize i = 0; i < break_events_.size (); i++)
 123     {
 124       string prefix;
 125       SCM name = break_events_[i]->get_property ("name");
 126       if (name == ly_symbol2scm ("LineBreakEvent"))
 127         prefix = "line-break";
 128       else if (name == ly_symbol2scm ("PageBreakEvent"))
 129         prefix = "page-break";
 130       else if (name == ly_symbol2scm ("PageTurnEvent"))
 131         prefix = "page-turn";
 132       else
 133         {
 134           programming_error ("Paper_column_engraver doesn't know about this break-event");
 135           return;
 136         }
 137       string perm_str = prefix + "-permission";
 138       string pen_str = prefix + "-penalty";
 139
 140       SCM cur_pen = command_column_->get_property (pen_str.c_str ());
 141       SCM pen = break_events_[i]->get_property ("break-penalty");
 142       SCM perm = break_events_[i]->get_property ("break-permission");
 143
 144       if (scm_is_number (pen))
 145         {
 146           Real new_pen = robust_scm2double (cur_pen, 0.0) + scm_to_double (pen);
 147           command_column_->set_property (pen_str.c_str (), scm_from_double (new_pen));
 148           command_column_->set_property (perm_str.c_str (), ly_symbol2scm ("allow"));
 149         }
 150       else
 151         command_column_->set_property (perm_str.c_str (), perm);
 152     }
 153
 154   bool start_of_measure = (last_moment_.main_part_ != now_mom ().main_part_
 155                            && !measure_position (context ()).main_part_);
 156
 157   /*
 158     We can't do this in start_translation_timestep(), since time sig
 159     changes won't have happened by then.
 160   */
 161   if (start_of_measure)
 162     {
 163       Moment mlen = Moment (measure_length (context ()));
 164       Grob *column = unsmob_grob (get_property ("currentCommandColumn"));
 165       if (column)
 166         column->set_property ("measure-length", mlen.smobbed_copy ());
 167       else
 168         programming_error ("No command column?");
 169     }
 170 }
 171
 172 void
 173 Paper_column_engraver::stop_translation_timestep ()
 174 {
 175   SCM m = now_mom ().smobbed_copy ();
 176   command_column_->set_property ("when", m);
 177   musical_column_->set_property ("when", m);
 178
 179   for (vsize i = 0; i < items_.size (); i++)
 180     {
 181       Item *elem = items_[i];
 182       if (!elem->get_parent (X_AXIS)
 183           || !unsmob_grob (elem->get_object ("axis-group-parent-X")))
 184         {
 185           bool br = Item::is_non_musical (elem);
 186           Axis_group_interface::add_element (br ? command_column_ : musical_column_, elem);
 187         }
 188     }
 189   items_.clear ();
 190
 191   if (to_boolean (get_property ("forbidBreak")))
 192     command_column_->set_property ("line-break-permission", SCM_EOL);
 193   else if (Paper_column::is_breakable (command_column_))
 194     {
 195       breaks_++;
 196       last_breakable_column_ = command_column_;
 197       last_breakable_moment_ = now_mom ();
 198       if (! (breaks_%8))
 199         progress_indication ("[" + to_string (breaks_) + "]");
 200     }
 201
 202   SCM page_br = get_property ("allowPageTurn");
 203   if (scm_is_pair (page_br) && last_breakable_moment_ >= Rational (0))
 204     {
 205       SCM pen = scm_cdr (page_br);
 206       Moment *m = unsmob_moment (scm_car (page_br));
 207       if (m && scm_is_number (pen) && *m <= last_breakable_moment_)
 208         {
 209           last_breakable_column_->set_property ("page-turn-permission", ly_symbol2scm ("allow"));
 210           last_breakable_column_->set_property ("page-turn-penalty", pen);
 211         }
 212     }
 213
 214   context ()->get_score_context ()->unset_property (ly_symbol2scm ("forbidBreak"));
 215   context ()->get_score_context ()->unset_property (ly_symbol2scm ("allowPageTurn"));
 216
 217   first_ = false;
 218   break_events_.clear ();
 219 }
 220
 221 void
 222 Paper_column_engraver::start_translation_timestep ()
 223 {
 224   /*
 225     TODO: don't make columns when skipTypesetting is true.
 226   */
 227   if (!first_)
 228     make_columns ();
 229 }
 230
 231 ADD_ACKNOWLEDGER (Paper_column_engraver, item);
 232 ADD_ACKNOWLEDGER (Paper_column_engraver, note_spacing);
 233 ADD_ACKNOWLEDGER (Paper_column_engraver, staff_spacing);
 234
 235 ADD_TRANSLATOR (Paper_column_engraver,
 236                 /* doc */ "Takes care of generating columns."
 237                 "\n\n "
 238                 "This engraver decides whether a column is breakable. The default is "
 239                 "that a column is always breakable. However, every Bar_engraver "
 240                 "that does not have a barline at a certain point will set forbidBreaks "
 241                 "in the score context to stop linebreaks.  In practice, this "
 242                 "means that you can make a breakpoint by creating a barline (assuming "
 243                 "that there are no beams or notes that prevent a breakpoint.) ",
 244
 245                 /* create */
 246                 "PaperColumn "
 247                 "NonMusicalPaperColumn",
 248
 249                 /* accept */ "break-event",
 250                 /* read */
 251                 "forbidBreak "
 252                 "allowPageTurn",
 253                 /* write */
 254                 "forbidBreak "
 255                 "allowPageTurn "
 256                 "currentCommandColumn "
 257                 "currentMusicalColumn");