lily/span-dynamic-performer.cc

   1 /*
   2   span-dynamic-performer.cc -- implement Span_dynamic_performer
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2000--2006 Jan Nieuwenhuizen <janneke@gnu.org>
   7 */
   8
   9 #include "performer.hh"
  10
  11 #include "audio-item.hh"
  12 #include "international.hh"
  13 #include "stream-event.hh"
  14
  15 #include "translator.icc"
  16
  17 /*
  18   TODO: fold this into 1 engraver: \< and \> should also stop when
  19   absdyn is encountered.
  20 */
  21 struct Audio_dynamic_tuple
  22 {
  23   Audio_dynamic *audio_;
  24   Moment mom_;
  25 };
  26
  27 /**
  28    perform span-dynamics
  29 */
  30 class Span_dynamic_performer : public Performer
  31 {
  32 public:
  33   TRANSLATOR_DECLARATIONS (Span_dynamic_performer);
  34
  35 protected:
  36   virtual void acknowledge_audio_element (Audio_element_info);
  37   void process_music ();
  38   void stop_translation_timestep ();
  39
  40   DECLARE_TRANSLATOR_LISTENER (decrescendo);
  41   DECLARE_TRANSLATOR_LISTENER (crescendo);
  42 private:
  43   Audio_dynamic *audio_;
  44   Real last_volume_;
  45   Stream_event *span_start_event_;
  46   Drul_array<Stream_event *> span_events_;
  47   vector<Audio_dynamic_tuple> dynamic_tuples_;
  48   vector<Audio_dynamic_tuple> finished_dynamic_tuples_;
  49   Direction dir_;
  50   Direction finished_dir_;
  51 };
  52
  53 Span_dynamic_performer::Span_dynamic_performer ()
  54 {
  55   span_events_[START] = 0;
  56   span_events_[STOP] = 0;
  57   span_start_event_ = 0;
  58   audio_ = 0;
  59   last_volume_ = 0;
  60 }
  61
  62 void
  63 Span_dynamic_performer::acknowledge_audio_element (Audio_element_info i)
  64 {
  65   if (Audio_dynamic *d = dynamic_cast<Audio_dynamic *> (i.elem_))
  66     last_volume_ = d->volume_;
  67 }
  68
  69 void
  70 Span_dynamic_performer::process_music ()
  71 {
  72   if (span_start_event_ || span_events_[START])
  73     {
  74       audio_ = new Audio_dynamic (0);
  75       Audio_element_info info (audio_, span_events_[START]
  76                                ? span_events_[START]
  77                                : span_events_[STOP]);
  78       announce_element (info);
  79       Audio_dynamic_tuple a = { audio_, now_mom () };
  80       dynamic_tuples_.push_back (a);
  81     }
  82
  83   if (span_events_[STOP])
  84     {
  85       if (!span_start_event_)
  86         {
  87           span_events_[STOP]->origin ()->warning (_ ("can't find start of (de)crescendo"));
  88           span_events_[STOP] = 0;
  89         }
  90       else
  91         {
  92           finished_dir_ = dir_;
  93           finished_dynamic_tuples_ = dynamic_tuples_;
  94         }
  95       dynamic_tuples_.clear ();
  96       span_start_event_ = 0;
  97     }
  98
  99   if (span_events_[START])
 100     {
 101       dir_ = (span_events_[START]->in_event_class ("crescendo-event"))
 102         ? RIGHT : LEFT;
 103       span_start_event_ = span_events_[START];
 104
 105       dynamic_tuples_.clear ();
 106       Audio_dynamic_tuple a = { audio_, now_mom () };
 107       dynamic_tuples_.push_back (a);
 108     }
 109
 110   if (span_events_[STOP])
 111     finished_dynamic_tuples_.back ().audio_->volume_ = last_volume_;
 112
 113   if (span_events_[START])
 114     dynamic_tuples_[0].audio_->volume_ = last_volume_;
 115
 116   span_events_[START] = 0;
 117   span_events_[STOP] = 0;
 118 }
 119
 120 void
 121 Span_dynamic_performer::stop_translation_timestep ()
 122 {
 123   if (finished_dynamic_tuples_.size () > 1)
 124     {
 125       Real start_volume = finished_dynamic_tuples_[0].audio_->volume_;
 126       Real dv = finished_dynamic_tuples_.back ().audio_->volume_
 127         - start_volume;
 128       /*
 129         urg.
 130         Catch and fix the case of:
 131
 132         |                         |
 133         x|                        x|
 134         f cresc.  -- -- -- -- --  pp
 135
 136         Actually, we should provide a non-displayed dynamic/volume setting,
 137         to set volume to 'ff' just before the pp.
 138       */
 139       if (!dv || sign (dv) != finished_dir_)
 140         {
 141           // urg.  20%: about two volume steps
 142           dv = (Real)finished_dir_ * 0.2;
 143           if (!start_volume)
 144             start_volume = finished_dynamic_tuples_.back ().audio_->volume_
 145               - dv;
 146         }
 147       Moment start_mom = finished_dynamic_tuples_[0].mom_;
 148       Moment dt = finished_dynamic_tuples_.back ().mom_ - start_mom;
 149       for (vsize i = 0; i < finished_dynamic_tuples_.size (); i++)
 150         {
 151           Audio_dynamic_tuple *a = &finished_dynamic_tuples_[i];
 152           Real volume = start_volume + dv * (Real) (a->mom_ - start_mom).main_part_
 153             / (Real)dt.main_part_;
 154           a->audio_->volume_ = volume;
 155         }
 156       finished_dynamic_tuples_.clear ();
 157     }
 158
 159   if (audio_)
 160     {
 161       audio_ = 0;
 162     }
 163
 164   span_events_[STOP] = 0;
 165   span_events_[START] = 0;
 166 }
 167
 168 IMPLEMENT_TRANSLATOR_LISTENER (Span_dynamic_performer, decrescendo);
 169 void
 170 Span_dynamic_performer::listen_decrescendo (Stream_event *r)
 171 {
 172   Direction d = to_dir (r->get_property ("span-direction"));
 173   span_events_[d] = r;
 174 }
 175
 176 IMPLEMENT_TRANSLATOR_LISTENER (Span_dynamic_performer, crescendo);
 177 void
 178 Span_dynamic_performer::listen_crescendo (Stream_event *r)
 179 {
 180   Direction d = to_dir (r->get_property ("span-direction"));
 181   span_events_[d] = r;
 182 }
 183
 184 ADD_TRANSLATOR (Span_dynamic_performer,
 185                 "", "",
 186                 "", "");