lily/time-scaled-music-iterator.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 1998--2010 Han-Wen Nienhuys <hanwen@xs4all.nl>,
   5                  Erik Sandberg <mandolaerik@gmail.com>
   6
   7   LilyPond is free software: you can redistribute it and/or modify
   8   it under the terms of the GNU General Public License as published by
   9   the Free Software Foundation, either version 3 of the License, or
  10   (at your option) any later version.
  11
  12   LilyPond is distributed in the hope that it will be useful,
  13   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15   GNU General Public License for more details.
  16
  17   You should have received a copy of the GNU General Public License
  18   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "context.hh"
  22 #include "input.hh"
  23 #include "international.hh"
  24 #include "music.hh"
  25 #include "music-wrapper-iterator.hh"
  26 #include "stream-event.hh"
  27
  28 /*
  29   Iterates \times, by sending TupletSpanEvents at the start/end of each
  30   tuplet bracket. Extra stop/start events are sent at regular
  31   intervals if tupletSpannerDuration is set.
  32 */
  33 class Time_scaled_music_iterator : public Music_wrapper_iterator
  34 {
  35 public:
  36   DECLARE_SCHEME_CALLBACK (constructor, ());
  37   /* construction */
  38   DECLARE_CLASSNAME (Time_scaled_music_iterator);
  39   Time_scaled_music_iterator ();
  40 protected:
  41   virtual void process (Moment m);
  42   virtual void construct_children ();
  43   virtual void derived_mark () const;
  44   virtual Moment pending_moment () const;
  45
  46   Music *create_event (Direction d);
  47
  48 private:
  49
  50   /* tupletSpannerDuration */
  51   Moment spanner_duration_;
  52
  53   /* next time to add a stop/start pair */
  54   Moment next_split_mom_;
  55
  56   /* Recycle start/stop events if tupletSpannerDuration is set. */
  57   SCM synthesized_events_;
  58
  59   Context_handle tuplet_handler_;
  60 };
  61
  62 Music*
  63 Time_scaled_music_iterator::create_event (Direction d)
  64 {
  65   SCM ev_scm = scm_call_2 (ly_lily_module_constant ("make-span-event"),
  66                            ly_symbol2scm ("TupletSpanEvent"),
  67                            scm_from_int (d));
  68
  69   Music *mus = get_music ();
  70
  71   Music *ev = unsmob_music (ev_scm);
  72   ev->set_spot (*mus->origin ());
  73   if (d == START)
  74     {
  75       ev->set_property ("numerator", mus->get_property ("numerator"));
  76       ev->set_property ("denominator", mus->get_property ("denominator"));
  77       ev->set_property ("tweaks", mus->get_property ("tweaks"));
  78       ev->set_property ("length", spanner_duration_.smobbed_copy ());
  79     }
  80
  81   synthesized_events_ = scm_cons (ev_scm, synthesized_events_);
  82   return ev;
  83 }
  84
  85
  86 Time_scaled_music_iterator::Time_scaled_music_iterator ()
  87 {
  88   spanner_duration_ = next_split_mom_ = 0;
  89   synthesized_events_ = SCM_EOL;
  90 }
  91
  92
  93 Moment
  94 Time_scaled_music_iterator::pending_moment () const
  95 {
  96   Moment next_mom = Music_wrapper_iterator::pending_moment ();
  97   next_mom = min (next_mom, next_split_mom_);
  98
  99   return next_mom;
 100 }
 101
 102
 103 void
 104 Time_scaled_music_iterator::process (Moment m)
 105 {
 106   if (spanner_duration_.to_bool () &&
 107       m.main_part_ == next_split_mom_)
 108     {
 109       descend_to_bottom_context ();
 110       if (tuplet_handler_.get_outlet ())
 111         create_event (STOP)->send_to_context (tuplet_handler_.get_outlet ());
 112
 113       if (m.main_part_ < music_get_length ().main_part_)
 114         {
 115           tuplet_handler_.set_context (get_outlet ());
 116           report_event (create_event (START));
 117
 118           next_split_mom_ += spanner_duration_;
 119         }
 120       else
 121         {
 122           tuplet_handler_.set_context (0);
 123         }
 124     }
 125   Music_wrapper_iterator::process (m);
 126   if (child_iter_ && child_iter_->ok ())
 127     descend_to_child (child_iter_->get_outlet ());
 128
 129 }
 130
 131 void
 132 Time_scaled_music_iterator::construct_children ()
 133 {
 134   spanner_duration_ = music_get_length ();
 135
 136   Moment *mp = unsmob_moment (get_outlet ()->get_property ("tupletSpannerDuration"));
 137   if (mp)
 138     spanner_duration_ = min (mp->main_part_, spanner_duration_);
 139
 140   Music_wrapper_iterator::construct_children ();
 141
 142   if (child_iter_ && child_iter_->ok ())
 143     descend_to_child (child_iter_->get_outlet ());
 144 }
 145
 146 void
 147 Time_scaled_music_iterator::derived_mark () const
 148 {
 149   scm_gc_mark (synthesized_events_);
 150   Music_wrapper_iterator::derived_mark ();
 151 }
 152
 153 IMPLEMENT_CTOR_CALLBACK (Time_scaled_music_iterator);