bool MidiFile::writeTrack(const MidiTrack &t)
{
write("MTrk", 4);
qint64 lenpos = fp->pos();
writeLong(0); // dummy len
status = -1;
int tick = 0;
for (auto i : t.events()) {
int ntick = i.first;
putvl(ntick - tick); // write tick delta
//
// if track channel != -1, then use this
// channel for all events in this track
//
if (t.outChannel() != -1)
writeEvent(i.second);
tick = ntick;
}
//---------------------------------------------------
// write "End Of Track" Meta
// write Track Len
//
putvl(1);
put(0xff); // Meta
put(0x2f); // EOT
putvl(0); // len 0
qint64 endpos = fp->pos();
fp->seek(lenpos);
writeLong(endpos-lenpos-4); // tracklen
fp->seek(endpos);
return false;
}
void MidiFile::writeEvent(const MidiEvent& event)
{
switch(event.type()) {
case ME_NOTEON:
writeStatus(ME_NOTEON, event.channel());
put(event.pitch());
put(event.velo());
break;
case ME_NOTEOFF:
writeStatus(ME_NOTEOFF, event.channel());
put(event.pitch());
put(event.velo());
break;
case ME_CONTROLLER:
switch(event.controller()) {
case CTRL_PROGRAM:
writeStatus(ME_PROGRAM, event.channel());
put(event.value() & 0x7f);
break;
case CTRL_PITCH:
{
writeStatus(ME_PITCHBEND, event.channel());
int v = event.value() + 8192;
put(v & 0x7f);
put((v >> 7) & 0x7f);
}
break;
case CTRL_PRESS:
writeStatus(ME_AFTERTOUCH, event.channel());
put(event.value() & 0x7f);
break;
default:
writeStatus(ME_CONTROLLER, event.channel());
put(event.controller());
put(event.value() & 0x7f);
break;
}
break;
case ME_META:
put(ME_META);
put(event.metaType());
putvl(event.len());
write(event.edata(), event.len());
resetRunningStatus(); // really ?!
break;
case ME_SYSEX:
put(ME_SYSEX);
putvl(event.len() + 1); // including 0xf7
write(event.edata(), event.len());
put(ME_ENDSYSEX);
resetRunningStatus();
break;
}
}
