lily/midi-walker.cc

   1 /*
   2   midi-walker.cc -- implement Midi_walker
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--1998 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7          Jan Nieuwenhuizen <janneke@gnu.org>
   8  */
   9
  10 #include "midi-walker.hh"
  11 #include "audio-column.hh"
  12 #include "audio-item.hh"
  13 #include "audio-staff.hh"
  14 #include "midi-item.hh"
  15 #include "midi-stream.hh"
  16 #include "debug.hh"
  17
  18 Midi_note_event::Midi_note_event()
  19 {
  20   ignore_b_ = false;
  21 }
  22
  23 int
  24 compare (Midi_note_event const& left, Midi_note_event const& right)
  25 {
  26   return sign (left.key - right.key);
  27 }
  28
  29 Midi_walker::Midi_walker (Audio_staff* audio_staff_l, Midi_track* track_l)
  30   : PCursor<Audio_item*>(audio_staff_l->audio_item_l_list_)
  31 {
  32   track_l_ = track_l;
  33   last_mom_ = 0;
  34 }
  35
  36 Midi_walker::~Midi_walker()
  37 {
  38   // ugh
  39   do_stop_notes (last_mom_ + Moment (10, 1));
  40 }
  41
  42 /**
  43   Find out if start_note event is needed, and do it if needed.
  44  */
  45 void
  46 Midi_walker::do_start_note (Midi_note* note_p)
  47 {
  48   Moment stop_mom = note_p->duration() + ptr ()->audio_column_l_->at_mom ();
  49   for (int i=0; i < stop_note_queue.size(); i++)
  50     {
  51       if (stop_note_queue[i].val->pitch_i() == note_p->pitch_i ())
  52         {
  53           if (stop_note_queue[i].key < stop_mom)
  54             stop_note_queue[i].ignore_b_ = true;
  55           else {
  56             // skip the stopnote
  57             delete note_p;
  58             return;
  59           }
  60         }
  61     }
  62
  63   Midi_note_event e;
  64   e.val = new Midi_note_off (note_p);
  65   e.key = stop_mom;
  66   stop_note_queue.insert (e);
  67
  68   output_event (ptr()->audio_column_l_->at_mom (), note_p);
  69 }
  70
  71 /**
  72   Output note events for all notes which end before #max_mom#
  73  */
  74 void
  75 Midi_walker::do_stop_notes (Moment max_mom)
  76 {
  77   while (stop_note_queue.size() && stop_note_queue.front ().key <= max_mom)
  78     {
  79       Midi_note_event e = stop_note_queue.get();
  80       if (e.ignore_b_)
  81         {
  82           delete e.val;
  83           continue;
  84         }
  85
  86       Moment stop_mom = e.key;
  87       Midi_note_off* note_p = e.val;
  88
  89       output_event (stop_mom, note_p);
  90     }
  91 }
  92
  93 /**
  94   Advance the track to #now#, output the item, and adjust current "moment".
  95  */
  96 void
  97 Midi_walker::output_event (Moment now_mom, Midi_item* l)
  98 {
  99   Moment delta_t = now_mom - last_mom_ ;
 100   last_mom_ += delta_t;
 101   track_l_->add (delta_t, l);
 102 }
 103
 104 void
 105 Midi_walker::process()
 106 {
 107   do_stop_notes (ptr()->audio_column_l_->at_mom ());
 108
 109   Midi_item* p = ptr()->midi_item_p ();
 110   if (!p)
 111     return;
 112   p->channel_i_ = track_l_->number_i_;
 113
 114   if (Midi_note *mi = dynamic_cast<Midi_note*>(p))
 115     do_start_note (mi);
 116   else
 117     output_event (ptr()->audio_column_l_->at_mom (), p);
 118 }
 119