lily/measure-grouping-engraver.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 2002--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 "warn.hh"
  21 #include "side-position-interface.hh"
  22 #include "global-context.hh"
  23 #include "engraver.hh"
  24 #include "spanner.hh"
  25 #include "beam-settings.hh"
  26
  27 #include "translator.icc"
  28
  29 class Measure_grouping_engraver : public Engraver
  30 {
  31 public:
  32   TRANSLATOR_DECLARATIONS (Measure_grouping_engraver);
  33
  34 protected:
  35   Spanner *grouping_;
  36   Rational stop_grouping_mom_;
  37
  38   void process_music ();
  39   virtual void finalize ();
  40   DECLARE_ACKNOWLEDGER (note_column);
  41 };
  42
  43 void
  44 Measure_grouping_engraver::finalize ()
  45 {
  46   if (grouping_)
  47     {
  48       grouping_->set_bound (RIGHT, unsmob_grob (get_property ("currentCommandColumn")));
  49       grouping_->suicide ();
  50       grouping_ = 0;
  51     }
  52 }
  53
  54 void
  55 Measure_grouping_engraver::acknowledge_note_column (Grob_info gi)
  56 {
  57   if (grouping_)
  58     Side_position_interface::add_support (grouping_, gi.grob ());
  59 }
  60
  61 void
  62 Measure_grouping_engraver::process_music ()
  63 {
  64   Moment now = now_mom ();
  65   if (grouping_ && now.main_part_ >= stop_grouping_mom_ && !now.grace_part_)
  66     {
  67       grouping_->set_bound (RIGHT,
  68                             unsmob_grob (get_property ("currentMusicalColumn")));
  69
  70       grouping_ = 0;
  71     }
  72
  73   if (now.grace_part_)
  74     return;
  75
  76   SCM settings = get_property ("beamSettings");
  77   SCM grouping = SCM_EOL;
  78   if (scm_is_pair (settings))
  79     {
  80       SCM time_signature_fraction = get_property ("timeSignatureFraction");
  81       grouping = ly_beam_grouping (settings,
  82                                    time_signature_fraction,
  83                                    ly_symbol2scm ("end"),
  84                                    ly_symbol2scm ("*"));
  85     }
  86   if (scm_is_pair (grouping))
  87     {
  88       Moment *measpos = unsmob_moment (get_property ("measurePosition"));
  89       Rational mp = measpos->main_part_;
  90
  91       Moment *beatlen_mom = unsmob_moment (get_property ("beatLength"));
  92       Rational beat_length = beatlen_mom->main_part_;
  93
  94       Rational where (0);
  95       for (SCM s = grouping; scm_is_pair (s);
  96            where += Rational ((int) scm_to_int (scm_car (s))) * beat_length,
  97              s = scm_cdr (s))
  98         {
  99           int grouplen = scm_to_int (scm_car (s));
 100           if (where == mp)
 101             {
 102               if (grouping_)
 103                 {
 104                   programming_error ("last grouping not finished yet");
 105                   continue;
 106                 }
 107               if (grouplen > 1)
 108                {
 109                  grouping_ = make_spanner ("MeasureGrouping", SCM_EOL);
 110                  grouping_->set_bound (LEFT, unsmob_grob (get_property ("currentMusicalColumn")));
 111
 112                  stop_grouping_mom_ = now.main_part_ + Rational (grouplen - 1) * beat_length;
 113                  get_global_context ()->add_moment_to_process (Moment (stop_grouping_mom_));
 114
 115                  if (grouplen == 3)
 116                    grouping_->set_property ("style", ly_symbol2scm ("triangle"));
 117                  else
 118                    grouping_->set_property ("style", ly_symbol2scm ("bracket"));
 119
 120                  break;
 121                }
 122             }
 123         }
 124     }
 125 }
 126
 127 Measure_grouping_engraver::Measure_grouping_engraver ()
 128 {
 129   grouping_ = 0;
 130 }
 131
 132 ADD_ACKNOWLEDGER (Measure_grouping_engraver, note_column);
 133 ADD_TRANSLATOR (Measure_grouping_engraver,
 134                 /* doc */
 135                 "Create @code{MeasureGrouping} to indicate beat subdivision.",
 136
 137                 /* create */
 138                 "MeasureGrouping ",
 139
 140                 /* read */
 141                 "beatLength "
 142                 "currentMusicalColumn "
 143                 "measurePosition "
 144                 "beamSettings ",
 145
 146                 /* write */
 147                 ""
 148                 );