midi2ly/midi-score-parser.cc

   1 /*
   2   midi-score-parser.cc -- implement
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--1998 Jan Nieuwenhuizen <janneke@gnu.org>
   7 */
   8
   9 #include "rational.hh"
  10 #include "source-file.hh"
  11 #include "source.hh"
  12 #include "midi2ly-global.hh"
  13 #include "midi-score-parser.hh"
  14 #include "midi-track-parser.hh"
  15 #include "mudela-item.hh"
  16 #include "mudela-score.hh"
  17
  18
  19 void
  20 Midi_score_parser::open (String filename_str, Sources* sources_l)
  21 {
  22   info_l_->source_l_ = sources_l->get_file_l (filename_str);
  23   if (!info_l_->source_l_)
  24     ::error (_f ("can't find file: `%s'", filename_str));
  25   info_l_->byte_L_ = (Byte const*)info_l_->source_l_->ch_C ();
  26   info_l_->end_byte_L_ = info_l_->byte_L_ + info_l_->source_l_->length_i () + 1;
  27 }
  28
  29 Mudela_score*
  30 Midi_score_parser::parse (String filename_str, Sources* sources_l)
  31 {
  32   Midi_parser_info info;
  33   info_l_ = &info;
  34   open (filename_str, sources_l);
  35   parse_header ();
  36   return parse_score ();
  37 }
  38
  39 void
  40 Midi_score_parser::parse_header ()
  41 {
  42   String str = get_str (4);
  43   if ( str != "MThd" )
  44     exit (_ ("MIDI header expected"));
  45
  46   int length_i = get_i (4);
  47   // is this signed?
  48   if (length_i < 6)
  49     exit (_ ("invalid header length"));
  50   info_l_->format_i_ = get_i (2);
  51   if (info_l_->format_i_ != 0 && info_l_->format_i_ != 1)
  52     exit (_("invalid MIDI format"));
  53   info_l_->tracks_i_ = get_i (2);
  54   if (info_l_->tracks_i_ < 0 || info_l_->tracks_i_ > 32 )
  55     exit (_("invalid number of tracks"));
  56   info_l_->division_1_i_ = get_i (2) * 4;
  57   if (info_l_->division_1_i_ < 0)
  58     exit (_ ("can't handle non-metrical time"));
  59   // ugh
  60   Duration::division_1_i_s = info_l_->division_1_i_;
  61   forward_byte_L (length_i - 6);
  62 }
  63
  64 int
  65 Midi_score_parser::find_earliest_i (Link_array<Midi_track_parser>& tracks)
  66 {
  67   int earliest_i = 0;
  68   Rational earliest_mom = infinity_rat;
  69   for (int i = 0; i < tracks.size(); i++)
  70     {
  71       if ( tracks [i]->at_mom () < earliest_mom )
  72         {
  73           earliest_mom = tracks [i]->at_mom ();
  74           earliest_i = i;
  75         }
  76     }
  77   return earliest_i;
  78 }
  79
  80 Mudela_score*
  81 Midi_score_parser::parse_score ()
  82 {
  83   int current_bar_i = 0;
  84   Mudela_time_signature m4 (4, 2, 24, 8);
  85   Rational bar4_mom = m4.bar_mom ();
  86
  87   Mudela_score* score_p = new Mudela_score( 1, 1, 1 );
  88   info_l_->score_l_ = score_p;
  89
  90   Link_array<Midi_track_parser> tracks;
  91   for (int i = 0; i < info_l_->tracks_i_; i++)
  92     tracks.push (new Midi_track_parser (info_l_, i));
  93
  94   LOGOUT (NORMAL_ver) << _ ("Parsing...");
  95   LOGOUT (NORMAL_ver) << "\n";
  96   while (tracks.size ())
  97     {
  98       int i = find_earliest_i (tracks);
  99       Rational at_mom = tracks [i]->at_mom ();
 100       Mudela_column* column_l = score_p->get_column_l (at_mom);
 101       Mudela_staff* staff_p = tracks [i]->parse (column_l);
 102       if ( staff_p )
 103         {
 104           score_p->add_staff (staff_p);
 105           delete tracks [i];
 106           tracks.del (i);
 107         }
 108
 109       //  brr, musta have some progress
 110       for (int ii = 0; !info_l_->bar_mom_ && ii < tracks.size (); ii++)
 111         info_l_->bar_mom_ = tracks [ii]->info_l_->bar_mom_;
 112
 113       int bar_i = (int) (at_mom
 114             / (info_l_->bar_mom_ ? info_l_->bar_mom_ : bar4_mom)) + 1;
 115       if (bar_i > current_bar_i)
 116         {
 117           LOGOUT (NORMAL_ver) << '[' << bar_i << ']' << flush;
 118           current_bar_i = bar_i;
 119         }
 120     }
 121   return score_p;
 122 }