lily/midi-walker.cc

   1 /*
   2   midi-walker.cc -- implement Midi_walker
   3
   4   source file of the LilyPond music typesetter
   5
   6   (c) 1997 Han-Wen Nienhuys <hanwen@stack.nl>, Jan Nieuwenhuizen <jan@digicash.com>
   7 */
   8
   9 #include "command-request.hh"
  10 #include "musical-request.hh"
  11 #include "p-score.hh"
  12 #include "staff.hh"
  13 #include "midi-walker.hh"
  14 #include "midi-item.hh"
  15 #include "midi-stream.hh"
  16 #include "debug.hh"
  17 #include "staff-column.hh"
  18
  19 Midi_walker::Midi_walker(Staff *st_l, Midi_track* track_l)
  20     : PCursor<Staff_column*>(st_l->cols_)
  21 {
  22     track_l_ = track_l;
  23     last_moment_= 0;
  24 }
  25
  26 /**
  27   output notestop events for all notes which end before #max_moment#
  28  */
  29 void
  30 Midi_walker::do_stop_notes(Moment max_moment)
  31 {
  32     while (stop_notes.size() && stop_notes.front_idx() <= max_moment) {
  33         Moment stop_moment = stop_notes.front_idx();
  34         Melodic_req * req_l = stop_notes.get();
  35
  36         Midi_note note(req_l, track_l_->number_i_, false);
  37         output_event(note, stop_moment);
  38     }
  39 }
  40 /**
  41   Find out if start_note event is needed,  and do it if needed.
  42  */
  43 void
  44 Midi_walker::do_start_note(Note_req*note_l)
  45 {
  46     Moment stop=note_l->duration() + ptr()->when();
  47     for(int i=0; i < stop_notes.size(); i++)
  48         if (stop_notes.value_arr_[i]->melodic()->pitch() ==
  49             note_l->pitch()) {
  50              if ( stop_notes.indices_arr_[i] < stop){
  51
  52                  stop_notes.del(i);
  53                  return ;  // removing this gives a feature ( ${c2 c4}$ output correctly)
  54              }
  55              else
  56                  return; // skip the stop note
  57              break;// do the stop note
  58         }
  59
  60     stop_notes.enter(note_l,  stop);
  61     Midi_note note(note_l, track_l_->number_i_, true);
  62     output_event(note, ptr()->when());
  63 }
  64
  65
  66 /** advance the track to #now#, output the item, and adjust current
  67   "moment".  */
  68 void
  69 Midi_walker::output_event(Midi_item &i, Moment now)
  70 {
  71     Moment delta_t = now - last_moment_ ;
  72     last_moment_ += delta_t;
  73     track_l_->add(delta_t, &i );
  74 }
  75
  76 void
  77 Midi_walker::process_requests()
  78 {
  79     do_stop_notes(ptr()->when());
  80
  81     for ( int i = 0; i < ptr()->commandreq_l_arr_.size(); i++ )  {
  82         Command_req *c_l = ptr()->commandreq_l_arr_[i]->command();
  83         Meter_change_req* meter_l = c_l->meterchange();
  84         if ( meter_l )
  85             output_event( Midi_time( meter_l->beats_i_, meter_l->one_beat_i_, 18 ),  0 );
  86         Key_change_req* key_l = c_l->keychange();
  87         if ( key_l ) {
  88             int sharps_i = key_l->sharps_i();
  89             int flats_i = key_l->flats_i();
  90             // midi cannot handle non-conventional keys
  91             if ( !( flats_i && sharps_i ) )
  92                 output_event( Midi_key( sharps_i - flats_i, key_l->minor_b() ), 0 );
  93         }
  94     }
  95
  96     for ( int i = 0; i < ptr()->musicalreq_l_arr_.size(); i++ )  {
  97
  98         Rhythmic_req *n = ptr()->musicalreq_l_arr_[i]->rhythmic();
  99         if ( !n)
 100             continue;
 101         Note_req * note_l = n->note();
 102         if (!note_l)
 103             continue;
 104         do_start_note(note_l);
 105
 106     }
 107 }
 108
 109 Midi_walker::~Midi_walker()
 110 {
 111     do_stop_notes( last_moment_ + Moment(10,1)); // ugh
 112 }