src/midiitem.cc

   1 //
   2 // midiitem.cc
   3 //
   4 // source file of the LilyPond music typesetter
   5 //
   6 // (c) 1997 Jan Nieuwenhuizen <jan@digicash.com>
   7
   8 #include <limits.h>
   9 #include "plist.hh"
  10 #include "pcol.hh"
  11 #include "debug.hh"
  12 #include "misc.hh"
  13 #include "request.hh"
  14 #include "musicalrequest.hh"
  15 #include "voice.hh"
  16 #include "midiitem.hh"
  17 #include "midistream.hh"
  18
  19 Midi_chunk::Midi_chunk()
  20 {
  21 }
  22
  23 void
  24 Midi_chunk::add( String str )
  25 {
  26     data_str_ += str;
  27 }
  28
  29 void
  30 Midi_chunk::set( String header_str, String data_str, String footer_str )
  31 {
  32     data_str_ = data_str;
  33     footer_str_ = footer_str;
  34     header_str_ = header_str;
  35 }
  36
  37 String
  38 Midi_chunk::str()
  39 {
  40     String str = header_str_;
  41     String length_str = String_convert::i2hex_str( data_str_.length_i() + footer_str_.length_i(), 8, '0' );
  42     length_str = String_convert::hex2bin_str( length_str );
  43     str += length_str;
  44     str += data_str_;
  45     str += footer_str_;
  46     return str;
  47 }
  48
  49 Midi_duration::Midi_duration( Real seconds_f )
  50 {
  51     seconds_f_ = seconds_f;
  52 }
  53
  54 String
  55 Midi_duration::str()
  56 {
  57     return String( "<duration: " ) + String( seconds_f_ ) + ">";
  58 }
  59
  60 Midi_header::Midi_header( int format_i, int tracks_i, int clocks_per_4_i )
  61 {
  62     String str;
  63
  64     String format_str = String_convert::i2hex_str( format_i, 4, '0' );
  65     str += String_convert::hex2bin_str( format_str );
  66
  67     String tracks_str = String_convert::i2hex_str( tracks_i, 4, '0' );
  68     str += String_convert::hex2bin_str( tracks_str );
  69
  70     String tempo_str = String_convert::i2hex_str( clocks_per_4_i, 4, '0' );
  71     str += String_convert::hex2bin_str( tempo_str );
  72
  73     set( "MThd", str, "" );
  74 }
  75
  76 String
  77 Midi_item::i2varint_str( int i )
  78 {
  79     int buffer_i = i & 0x7f;
  80     while ( (i >>= 7) > 0 ) {
  81         buffer_i <<= 8;
  82         buffer_i |= 0x80;
  83         buffer_i += (i & 0x7f);
  84     }
  85
  86     String str;
  87     while ( 1 ) {
  88         str += (char)buffer_i;
  89         if ( buffer_i & 0x80 )
  90             buffer_i >>= 8;
  91         else
  92             break;
  93     }
  94     return str;
  95 }
  96
  97 void
  98 Midi_item::output_midi( Midi_stream& midi_stream_r )
  99 {
 100     midi_stream_r << str();
 101 }
 102
 103
 104 Midi_note::Midi_note( Melodic_req* melreq_l, int channel_i, bool on_bo  )
 105 {
 106     assert(melreq_l);
 107     pitch_i_ = melreq_l->pitch() + c0_pitch_i_c_;
 108     channel_i_ = channel_i;
 109
 110     // poor man-s staff dynamics:
 111     dynamic_byte_ =  (melreq_l)? 0x64 - 0x10 * channel_i_:0;
 112     on_b_ = on_bo;
 113 }
 114
 115 String
 116 Midi_note::str()
 117 {
 118     if ( pitch_i_ != INT_MAX ) {
 119         Byte status_byte = ( on_b_ ? 0x90 : 0x80 ) + channel_i_;
 120         String str = String( (char)status_byte );
 121         str += (char)pitch_i_;
 122         // poor man-s staff dynamics:
 123         str += (char)dynamic_byte_;
 124         return str;
 125     }
 126     return String( "" );
 127 }
 128
 129 Midi_tempo::Midi_tempo( int tempo_i )
 130 {
 131     tempo_i_ = tempo_i;
 132 }
 133
 134 String
 135 Midi_tempo::str()
 136 {
 137     int useconds_per_4_i = 60 * (int)1e6 / tempo_i_;
 138     String str = "ff5103";
 139     str += String_convert::i2hex_str( useconds_per_4_i, 6, '0' );
 140     return String_convert::hex2bin_str( str );
 141 }
 142
 143 Midi_track::Midi_track( int number_i )
 144 {
 145 //                4D 54 72 6B     MTrk
 146 //                00 00 00 3B     chunk length (59)
 147 //        00      FF 58 04 04 02 18 08    time signature
 148 //        00      FF 51 03 07 A1 20       tempo
 149
 150 // FF 59 02 sf mi  Key Signature
 151 //         sf = -7:  7 flats
 152 //         sf = -1:  1 flat
 153 //         sf = 0:  key of C
 154 //         sf = 1:  1 sharp
 155 //         sf = 7: 7 sharps
 156 //         mi = 0:  major key
 157 //         mi = 1:  minor key
 158
 159     number_i_ = number_i;
 160
 161     char const* data_ch_c_l = "00" "ff58" "0404" "0218" "08"
 162 //      "00" "ff51" "0307" "a120"
 163 // why a key at all, in midi?
 164 // key: C
 165         "00" "ff59" "02" "00" "00"
 166 // key: F (scsii-menuetto)
 167 //                                "00" "ff59" "02" "ff" "00"
 168         ;
 169
 170     String data_str;
 171     // only for format 0 (currently using format 1)?
 172     data_str += String_convert::hex2bin_str( data_ch_c_l );
 173
 174     char const* footer_ch_c_l = "00" "ff2f" "00";
 175     String footer_str = String_convert::hex2bin_str( footer_ch_c_l );
 176
 177     set( "MTrk", data_str, footer_str );
 178 }
 179
 180 void
 181 Midi_track::add( int delta_time_i, String event_str )
 182 {
 183     assert(delta_time_i >= 0);
 184     Midi_chunk::add( i2varint_str( delta_time_i ) + event_str );
 185 }
 186
 187 void
 188 Midi_track::add( Moment delta_time_moment, Midi_item* mitem_l )
 189 {
 190     // use convention of 384 clocks per 4
 191     // use Duration_convert
 192     int delta_time_i = delta_time_moment * Moment( 384 ) / Moment( 1, 4 );
 193     add( delta_time_i, mitem_l->str() );
 194 }
 195