src/midi-item.cc

   1 //
   2 // midi-item.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 "midi-item.hh"
  17 #include "midi-stream.hh"
  18 #include "string-convert.hh"
  19
  20 Midi_chunk::Midi_chunk()
  21 {
  22 }
  23
  24 void
  25 Midi_chunk::add( String str )
  26 {
  27     data_str_ += str;
  28 }
  29
  30 void
  31 Midi_chunk::set( String header_str, String data_str, String footer_str )
  32 {
  33     data_str_ = data_str;
  34     footer_str_ = footer_str;
  35     header_str_ = header_str;
  36 }
  37
  38 String
  39 Midi_chunk::str()
  40 {
  41     String str = header_str_;
  42     String length_str = String_convert::i2hex_str( data_str_.length_i() + footer_str_.length_i(), 8, '0' );
  43     length_str = String_convert::hex2bin_str( length_str );
  44     str += length_str;
  45     str += data_str_;
  46     str += footer_str_;
  47     return str;
  48 }
  49
  50 Midi_duration::Midi_duration( Real seconds_f )
  51 {
  52     seconds_f_ = seconds_f;
  53 }
  54
  55 String
  56 Midi_duration::str()
  57 {
  58     return String( "<duration: " ) + String( seconds_f_ ) + ">";
  59 }
  60
  61 Midi_header::Midi_header( int format_i, int tracks_i, int clocks_per_4_i )
  62 {
  63     String str;
  64
  65     String format_str = String_convert::i2hex_str( format_i, 4, '0' );
  66     str += String_convert::hex2bin_str( format_str );
  67
  68     String tracks_str = String_convert::i2hex_str( tracks_i, 4, '0' );
  69     str += String_convert::hex2bin_str( tracks_str );
  70
  71     String tempo_str = String_convert::i2hex_str( clocks_per_4_i, 4, '0' );
  72     str += String_convert::hex2bin_str( tempo_str );
  73
  74     set( "MThd", str, "" );
  75 }
  76
  77 String
  78 Midi_item::i2varint_str( int i )
  79 {
  80     int buffer_i = i & 0x7f;
  81     while ( (i >>= 7) > 0 ) {
  82         buffer_i <<= 8;
  83         buffer_i |= 0x80;
  84         buffer_i += (i & 0x7f);
  85     }
  86
  87     String str;
  88     while ( 1 ) {
  89         str += (char)buffer_i;
  90         if ( buffer_i & 0x80 )
  91             buffer_i >>= 8;
  92         else
  93             break;
  94     }
  95     return str;
  96 }
  97
  98 void
  99 Midi_item::output_midi( Midi_stream& midi_stream_r )
 100 {
 101     midi_stream_r << str();
 102 }
 103
 104
 105 Midi_note::Midi_note( Melodic_req* melreq_l, int channel_i, bool on_bo  )
 106 {
 107     assert(melreq_l);
 108     pitch_i_ = melreq_l->pitch() + c0_pitch_i_c_;
 109     channel_i_ = channel_i;
 110
 111     // poor man-s staff dynamics:
 112     dynamic_byte_ =  (melreq_l)? 0x64 - 0x10 * channel_i_:0;
 113     on_b_ = on_bo;
 114 }
 115
 116 String
 117 Midi_note::str()
 118 {
 119     if ( pitch_i_ != INT_MAX ) {
 120         Byte status_byte = ( on_b_ ? 0x90 : 0x80 ) + channel_i_;
 121         String str = String( (char)status_byte );
 122         str += (char)pitch_i_;
 123         // poor man-s staff dynamics:
 124         str += (char)dynamic_byte_;
 125         return str;
 126     }
 127     return String( "" );
 128 }
 129
 130 Midi_tempo::Midi_tempo( int tempo_i )
 131 {
 132     tempo_i_ = tempo_i;
 133 }
 134
 135 String
 136 Midi_tempo::str()
 137 {
 138     int useconds_per_4_i = 60 * (int)1e6 / tempo_i_;
 139     String str = "ff5103";
 140     str += String_convert::i2hex_str( useconds_per_4_i, 6, '0' );
 141     return String_convert::hex2bin_str( str );
 142 }
 143
 144 Midi_track::Midi_track( int number_i )
 145 {
 146 //                4D 54 72 6B     MTrk
 147 //                00 00 00 3B     chunk length (59)
 148 //        00      FF 58 04 04 02 18 08    time signature
 149 //        00      FF 51 03 07 A1 20       tempo
 150
 151 // FF 59 02 sf mi  Key Signature
 152 //         sf = -7:  7 flats
 153 //         sf = -1:  1 flat
 154 //         sf = 0:  key of C
 155 //         sf = 1:  1 sharp
 156 //         sf = 7: 7 sharps
 157 //         mi = 0:  major key
 158 //         mi = 1:  minor key
 159
 160     number_i_ = number_i;
 161
 162     char const* data_ch_c_l = "00" "ff58" "0404" "0218" "08"
 163 //      "00" "ff51" "0307" "a120"
 164 // why a key at all, in midi?
 165 // key: C
 166         "00" "ff59" "02" "00" "00"
 167 // key: F (scsii-menuetto)
 168 //                                "00" "ff59" "02" "ff" "00"
 169         ;
 170
 171     String data_str;
 172     // only for format 0 (currently using format 1)?
 173     data_str += String_convert::hex2bin_str( data_ch_c_l );
 174
 175     char const* footer_ch_c_l = "00" "ff2f" "00";
 176     String footer_str = String_convert::hex2bin_str( footer_ch_c_l );
 177
 178     set( "MTrk", data_str, footer_str );
 179 }
 180
 181 void
 182 Midi_track::add( int delta_time_i, String event_str )
 183 {
 184     assert(delta_time_i >= 0);
 185     Midi_chunk::add( i2varint_str( delta_time_i ) + event_str );
 186 }
 187
 188 void
 189 Midi_track::add( Moment delta_time_moment, Midi_item* mitem_l )
 190 {
 191     // use convention of 384 clocks per 4
 192     // use Duration_convert
 193     int delta_time_i = delta_time_moment * Moment( 384 ) / Moment( 1, 4 );
 194     add( delta_time_i, mitem_l->str() );
 195 }
 196