lily/volta-engraver.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 2000--2010 Han-Wen Nienhuys <hanwen@xs4all.nl>
   5
   6   LilyPond is free software: you can redistribute it and/or modify
   7   it under the terms of the GNU General Public License as published by
   8   the Free Software Foundation, either version 3 of the License, or
   9   (at your option) any later version.
  10
  11   LilyPond is distributed in the hope that it will be useful,
  12   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14   GNU General Public License for more details.
  15
  16   You should have received a copy of the GNU General Public License
  17   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "engraver.hh"
  21
  22 #include "axis-group-interface.hh"
  23 #include "bar-line.hh"
  24 #include "context.hh"
  25 #include "grob-array.hh"
  26 #include "international.hh"
  27 #include "note-column.hh"
  28 #include "item.hh"
  29 #include "side-position-interface.hh"
  30 #include "staff-symbol.hh"
  31 #include "text-interface.hh"
  32 #include "volta-bracket.hh"
  33 #include "warn.hh"
  34
  35 #include "translator.icc"
  36
  37 /*
  38   Create Volta spanners, by reading repeatCommands  property, usually
  39   set by Volta_repeat_iterator.
  40 */
  41 class Volta_engraver : public Engraver
  42 {
  43 public:
  44   TRANSLATOR_DECLARATIONS (Volta_engraver);
  45 protected:
  46
  47   DECLARE_ACKNOWLEDGER (bar_line);
  48
  49   virtual void derived_mark () const;
  50   void stop_translation_timestep ();
  51   void process_music ();
  52
  53   Moment started_mom_;
  54   Spanner *volta_bracket_;
  55   Spanner *end_volta_bracket_;
  56   Spanner *volta_spanner_;
  57   SCM start_string_;
  58 };
  59
  60 void
  61 Volta_engraver::derived_mark () const
  62 {
  63   scm_gc_mark (start_string_);
  64 }
  65
  66 Volta_engraver::Volta_engraver ()
  67 {
  68   start_string_ = SCM_EOL;
  69   volta_bracket_ = 0;
  70   end_volta_bracket_ = 0;
  71   volta_spanner_ = 0;
  72 }
  73
  74 void
  75 Volta_engraver::process_music ()
  76 {
  77   SCM cs = get_property ("repeatCommands");
  78
  79   bool end = false;
  80   start_string_ = SCM_EOL;
  81   while (scm_is_pair (cs))
  82     {
  83       SCM c = scm_car (cs);
  84
  85       if (scm_is_pair (c)
  86           && scm_car (c) == ly_symbol2scm ("volta")
  87           && scm_is_pair (scm_cdr (c)))
  88         {
  89           if (scm_cadr (c) == SCM_BOOL_F)
  90             end = true;
  91           else
  92             start_string_ = scm_cadr (c);
  93         }
  94
  95       cs = scm_cdr (cs);
  96     }
  97
  98   if (volta_bracket_)
  99     {
 100       SCM l (get_property ("voltaSpannerDuration"));
 101       Moment now = now_mom ();
 102
 103       bool early_stop = unsmob_moment (l)
 104         && *unsmob_moment (l) <= now - started_mom_;
 105
 106       end = end || early_stop;
 107     }
 108
 109   if (end && !volta_bracket_)
 110     /* fixme: be more verbose.  */
 111     warning (_ ("cannot end volta spanner"));
 112   else if (end)
 113     {
 114       end_volta_bracket_ = volta_bracket_;
 115       volta_bracket_ = 0;
 116     }
 117
 118   if (volta_bracket_
 119       && (scm_is_string (start_string_) || scm_is_pair (start_string_)))
 120     {
 121       warning (_ ("already have a volta spanner, ending that one prematurely"));
 122
 123       if (end_volta_bracket_)
 124         {
 125           warning (_ ("also already have an ended spanner"));
 126           warning (_ ("giving up"));
 127           return;
 128         }
 129
 130       end_volta_bracket_ = volta_bracket_;
 131       volta_bracket_ = 0;
 132     }
 133
 134   if (!volta_bracket_
 135       && Text_interface::is_markup (start_string_))
 136     {
 137       started_mom_ = now_mom ();
 138
 139       volta_bracket_ = make_spanner ("VoltaBracket", SCM_EOL);
 140
 141       volta_bracket_->set_property ("text", start_string_);
 142
 143       if (!volta_spanner_)
 144         volta_spanner_ = make_spanner ("VoltaBracketSpanner", SCM_EOL);
 145
 146       Axis_group_interface::add_element (volta_spanner_, volta_bracket_);
 147     }
 148 }
 149
 150 void
 151 Volta_engraver::acknowledge_bar_line (Grob_info i)
 152 {
 153   if (volta_bracket_)
 154     Volta_bracket_interface::add_bar (volta_bracket_, i.item ());
 155   if (end_volta_bracket_)
 156     Volta_bracket_interface::add_bar (end_volta_bracket_, i.item ());
 157
 158   if (volta_spanner_)
 159     Side_position_interface::add_support (volta_spanner_, i.grob ());
 160 }
 161
 162 void
 163 Volta_engraver::stop_translation_timestep ()
 164 {
 165   Grob *cc = unsmob_grob (get_property ("currentCommandColumn"));
 166   Item *ci = dynamic_cast<Item *> (cc);
 167
 168   if (end_volta_bracket_ && !end_volta_bracket_->get_bound (RIGHT))
 169     end_volta_bracket_->set_bound (RIGHT, ci);
 170
 171   if (volta_spanner_ && end_volta_bracket_)
 172     volta_spanner_->set_bound (RIGHT, end_volta_bracket_->get_bound (RIGHT));
 173
 174   if (end_volta_bracket_ && !volta_bracket_)
 175     {
 176       for (SCM s = get_property ("stavesFound"); scm_is_pair (s); s = scm_cdr (s))
 177         Side_position_interface::add_support (volta_spanner_, unsmob_grob (scm_car (s)));
 178       volta_spanner_ = 0;
 179     }
 180
 181   end_volta_bracket_ = 0;
 182
 183   if (volta_bracket_ && !volta_bracket_->get_bound (LEFT))
 184     volta_bracket_->set_bound (LEFT, ci);
 185
 186   if (volta_spanner_ && volta_bracket_ && !volta_spanner_->get_bound (LEFT))
 187     volta_spanner_->set_bound (LEFT, volta_bracket_->get_bound (LEFT));
 188 }
 189
 190 /*
 191   TODO: should attach volta to paper-column if no bar is found.
 192 */
 193 ADD_ACKNOWLEDGER (Volta_engraver, bar_line);
 194 ADD_TRANSLATOR (Volta_engraver,
 195                 /* doc */
 196                 "Make volta brackets.",
 197
 198                 /* create */
 199                 "VoltaBracket "
 200                 "VoltaBracketSpanner ",
 201
 202                 /* read */
 203                 "repeatCommands "
 204                 "voltaSpannerDuration "
 205                 "stavesFound ",
 206
 207                 /* write */
 208                 ""
 209                 );