lily/measure-grouping-engraver.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 2002--2011 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
  26 #include "translator.icc"
  27
  28 class Measure_grouping_engraver : public Engraver
  29 {
  30 public:
  31   TRANSLATOR_DECLARATIONS (Measure_grouping_engraver);
  32
  33 protected:
  34   Spanner *grouping_;
  35   Rational stop_grouping_mom_;
  36
  37   void process_music ();
  38   virtual void finalize ();
  39   DECLARE_ACKNOWLEDGER (note_column);
  40 };
  41
  42 void
  43 Measure_grouping_engraver::finalize ()
  44 {
  45   if (grouping_)
  46     {
  47       grouping_->set_bound (RIGHT, unsmob_grob (get_property ("currentCommandColumn")));
  48       grouping_->suicide ();
  49       grouping_ = 0;
  50     }
  51 }
  52
  53 void
  54 Measure_grouping_engraver::acknowledge_note_column (Grob_info gi)
  55 {
  56   if (grouping_)
  57     Side_position_interface::add_support (grouping_, gi.grob ());
  58 }
  59
  60 void
  61 Measure_grouping_engraver::process_music ()
  62 {
  63   Moment now = now_mom ();
  64   if (grouping_ && now.main_part_ >= stop_grouping_mom_ && !now.grace_part_)
  65     {
  66       grouping_->set_bound (RIGHT,
  67                             unsmob_grob (get_property ("currentMusicalColumn")));
  68
  69       grouping_ = 0;
  70     }
  71
  72   if (now.grace_part_)
  73     return;
  74
  75   SCM grouping = get_property ("beatStructure");
  76   if (scm_is_pair (grouping))
  77     {
  78       Moment *measpos = unsmob_moment (get_property ("measurePosition"));
  79       Rational mp = measpos->main_part_;
  80
  81       Moment *base_mom = unsmob_moment (get_property ("baseMoment"));
  82       Rational base_moment = base_mom->main_part_;
  83
  84       Rational where (0);
  85       for (SCM s = grouping; scm_is_pair (s);
  86            where += Rational ((int) scm_to_int (scm_car (s))) * base_moment,
  87              s = scm_cdr (s))
  88         {
  89           int grouplen = scm_to_int (scm_car (s));
  90           if (where == mp)
  91             {
  92               if (grouping_)
  93                 {
  94                   programming_error ("last grouping not finished yet");
  95                   continue;
  96                 }
  97               if (grouplen > 1)
  98                {
  99                  grouping_ = make_spanner ("MeasureGrouping", SCM_EOL);
 100                  grouping_->set_bound (LEFT, unsmob_grob (get_property ("currentMusicalColumn")));
 101
 102                  stop_grouping_mom_ = now.main_part_ + Rational (grouplen - 1) * base_moment;
 103                  get_global_context ()->add_moment_to_process (Moment (stop_grouping_mom_));
 104
 105                  if (grouplen == 3)
 106                    grouping_->set_property ("style", ly_symbol2scm ("triangle"));
 107                  else
 108                    grouping_->set_property ("style", ly_symbol2scm ("bracket"));
 109
 110                  break;
 111                }
 112             }
 113         }
 114     }
 115 }
 116
 117 Measure_grouping_engraver::Measure_grouping_engraver ()
 118 {
 119   grouping_ = 0;
 120 }
 121
 122 ADD_ACKNOWLEDGER (Measure_grouping_engraver, note_column);
 123 ADD_TRANSLATOR (Measure_grouping_engraver,
 124                 /* doc */
 125                 "Create @code{MeasureGrouping} to indicate beat subdivision.",
 126
 127                 /* create */
 128                 "MeasureGrouping ",
 129
 130                 /* read */
 131                 "baseMoment "
 132                 "beatStructure "
 133                 "currentMusicalColumn "
 134                 "measurePosition ",
 135
 136                 /* write */
 137                 ""
 138                 );