lily/time-scaled-music-iterator.cc

   1 /*
   2   time-scaled-music-iterator.cc -- implement Time_scaled_music_iterator
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1998--2009 Han-Wen Nienhuys <hanwen@xs4all.nl>,
   7                  Erik Sandberg <mandolaerik@gmail.com>
   8 */
   9
  10 #include "context.hh"
  11 #include "input.hh"
  12 #include "international.hh"
  13 #include "music.hh"
  14 #include "music-wrapper-iterator.hh"
  15 #include "stream-event.hh"
  16
  17 /*
  18   Iterates \times, by sending TupletSpanEvents at the start/end of each
  19   tuplet bracket. Extra stop/start events are sent at regular
  20   intervals if tupletSpannerDuration is set.
  21 */
  22 class Time_scaled_music_iterator : public Music_wrapper_iterator
  23 {
  24 public:
  25   DECLARE_SCHEME_CALLBACK (constructor, ());
  26   /* construction */
  27   DECLARE_CLASSNAME (Time_scaled_music_iterator);
  28   Time_scaled_music_iterator ();
  29 protected:
  30   virtual void process (Moment m);
  31   virtual void construct_children ();
  32   virtual void derived_mark () const;
  33   virtual Moment pending_moment () const;
  34
  35   Music *create_event (Direction d);
  36
  37 private:
  38
  39   /* tupletSpannerDuration */
  40   Moment spanner_duration_;
  41
  42   /* next time to add a stop/start pair */
  43   Moment next_split_mom_;
  44
  45   /* Recycle start/stop events if tupletSpannerDuration is set. */
  46   SCM synthesized_events_;
  47
  48   Context_handle tuplet_handler_;
  49 };
  50
  51 Music*
  52 Time_scaled_music_iterator::create_event (Direction d)
  53 {
  54   SCM ev_scm = scm_call_2 (ly_lily_module_constant ("make-span-event"),
  55                            ly_symbol2scm ("TupletSpanEvent"),
  56                            scm_from_int (d));
  57
  58   Music *mus = get_music ();
  59
  60   Music *ev = unsmob_music (ev_scm);
  61   ev->set_spot (*mus->origin ());
  62   if (d == START)
  63     {
  64       ev->set_property ("numerator", mus->get_property ("numerator"));
  65       ev->set_property ("denominator", mus->get_property ("denominator"));
  66       ev->set_property ("tweaks", mus->get_property ("tweaks"));
  67       ev->set_property ("length", spanner_duration_.smobbed_copy ());
  68     }
  69
  70   synthesized_events_ = scm_cons (ev_scm, synthesized_events_);
  71   return ev;
  72 }
  73
  74
  75 Time_scaled_music_iterator::Time_scaled_music_iterator ()
  76 {
  77   spanner_duration_ = next_split_mom_ = 0;
  78   synthesized_events_ = SCM_EOL;
  79 }
  80
  81
  82 Moment
  83 Time_scaled_music_iterator::pending_moment () const
  84 {
  85   Moment next_mom = Music_wrapper_iterator::pending_moment ();
  86   next_mom = min (next_mom, next_split_mom_);
  87
  88   return next_mom;
  89 }
  90
  91
  92 void
  93 Time_scaled_music_iterator::process (Moment m)
  94 {
  95   if (spanner_duration_.to_bool () &&
  96       m.main_part_ == next_split_mom_)
  97     {
  98       descend_to_bottom_context ();
  99       if (tuplet_handler_.get_outlet ())
 100         create_event (STOP)->send_to_context (tuplet_handler_.get_outlet ());
 101
 102       if (m.main_part_ < music_get_length ().main_part_)
 103         {
 104           tuplet_handler_.set_context (get_outlet ());
 105           report_event (create_event (START));
 106
 107           next_split_mom_ += spanner_duration_;
 108         }
 109       else
 110         {
 111           tuplet_handler_.set_context (0);
 112         }
 113     }
 114   Music_wrapper_iterator::process (m);
 115   if (child_iter_ && child_iter_->ok ())
 116     descend_to_child (child_iter_->get_outlet ());
 117
 118 }
 119
 120 void
 121 Time_scaled_music_iterator::construct_children ()
 122 {
 123   spanner_duration_ = music_get_length ();
 124
 125   Moment *mp = unsmob_moment (get_outlet ()->get_property ("tupletSpannerDuration"));
 126   if (mp)
 127     spanner_duration_ = min (mp->main_part_, spanner_duration_);
 128
 129   Music_wrapper_iterator::construct_children ();
 130
 131   if (child_iter_ && child_iter_->ok ())
 132     descend_to_child (child_iter_->get_outlet ());
 133 }
 134
 135 void
 136 Time_scaled_music_iterator::derived_mark () const
 137 {
 138   scm_gc_mark (synthesized_events_);
 139   Music_wrapper_iterator::derived_mark ();
 140 }
 141
 142 IMPLEMENT_CTOR_CALLBACK (Time_scaled_music_iterator);