int AdvancedSequencer::FindFirstChannelOnTrack ( int trk )
{
if ( !file_loaded )
{
return -1;
}
int first_channel = -1;
MIDITrack *t = tracks.GetTrack ( trk );
if ( t )
{
// go through all events
// until we find a channel message
// and then return the channel number plus 1
for ( int i = 0; i < t->GetNumEvents(); ++i )
{
MIDITimedBigMessage *m = t->GetEventAddress ( i );
if ( m )
{
if ( m->IsChannelMsg() )
{
first_channel = m->GetChannel() + 1;
break;
}
}
}
}
return first_channel;
}
MIDITrack::MIDITrack( const MIDITrack &t )
{
buf_size=0;
num_events=0;
for( int i=0; i<t.GetNumEvents(); ++i )
{
const MIDITimedBigMessage *src;
src = t.GetEventAddress( i );
PutEvent(*src);
}
}
bool MIDIMultiTrackIterator::GoToNextEventOnTrack ( int track_num )
{
// Get the track that we are dealing with
MIDITrack *track = multitrack->GetTrack ( track_num );
// Get ptr to the current event number for this track
int *event_num = &state.next_event_number[ track_num ];
// skip this track if this event number is <0 - This track has hit end already.
if ( *event_num <0 )
{
return false; // at end of track
}
// increment *event_num to next event on track
( *event_num ) += 1;
// are we at end of track?
if ( *event_num >= track->GetNumEvents() )
{
// yes, set *event_num to -1
*event_num=-1;
return false; // at end of track
}
else
{
// not at end of track yet - get the time of the event
MIDITimedBigMessage *msg;
msg = track->GetEventAddress ( *event_num );
state.next_event_time[ track_num ] = msg->GetTime();
}
return true;
}
void AdvancedSequencer::ExtractMarkers ( std::vector< std::string > *list )
{
if ( !file_loaded )
{
list->clear();
num_markers = 0;
return;
}
MIDITrack *t = tracks.GetTrack ( 0 );
list->clear();
int cnt = 0;
int measure = 0;
int beat = 0;
int timesig_numerator = 4;
int timesig_denominator = 4;
MIDIClockTime last_beat_time = 0;
MIDIClockTime last_event_time = 0;
int clks_per_beat = tracks.GetClksPerBeat();
for ( int i = 0; i < t->GetNumEvents(); ++i )
{
MIDITimedBigMessage *m = t->GetEventAddress ( i );
if ( m )
{
// how many beats have gone by since the last event?
long beats_gone_by = ( m->GetTime() - last_beat_time ) / clks_per_beat;
if ( beats_gone_by > 0 )
{
// calculate what our new measure/beat is
beat += beats_gone_by;
// carry over beat overflow to measure
measure += beat / timesig_numerator;
beat = beat % timesig_numerator;
last_beat_time += ( clks_per_beat * beats_gone_by );
}
if ( m->IsMetaEvent() && m->IsTimeSig() )
{
timesig_numerator = m->GetTimeSigNumerator();
timesig_denominator = m->GetTimeSigDenominator();
clks_per_beat = tracks.GetClksPerBeat() * 4 / timesig_denominator;
}
if ( m->IsTextEvent() && m->GetSysEx() )
{
if ( ( m->GetMetaType() == META_GENERIC_TEXT )
|| m->GetMetaType() == META_MARKER_TEXT
|| m->GetMetaType() == META_CUE_TEXT )
{
char buf[256];
char line[256];
memcpy ( buf, m->GetSysEx()->GetBuf(), m->GetSysEx()->GetLength() );
buf[ m->GetSysEx()->GetLength() ] = '\0';
FixQuotes ( buf );
sprintf ( line, "%03d:%d %s", measure + 1, beat + 1, buf );
list->push_back ( std::string ( line ) );
marker_times[ cnt++ ] = m->GetTime();
}
}
last_event_time = m->GetTime();
}
}
num_markers = cnt;
}
void MIDIMultiTrackIterator::GoToTime ( MIDIClockTime time )
{
// start at time 0
state.Reset();
// transfer info from the first events in each track in the
// multitrack object to our current state.
for ( int i=0; i<multitrack->GetNumTracks(); ++i )
{
MIDITrack *track = multitrack->GetTrack ( i );
// default: set the next_event_number for this track to -1
// to signify end of track
state.next_event_number[ i ] = -1;
// are there any events in this track?
if ( track && track->GetNumEvents() >0 )
{
// yes, extract the time of the first event
MIDITimedBigMessage *msg = track->GetEventAddress ( 0 );
if ( msg )
{
// found the first message of the track. Keep track
// of the event number and the event time.
state.next_event_number[i]=0;
state.next_event_time[i]=msg->GetTime();
}
}
}
// are there any events at all? find the track with the
// earliest event
if ( state.FindTrackOfFirstEvent() !=-1 )
{
// yes
// iterate through all the events until we find a time >= the requested time
while ( state.GetCurrentTime() <time )
{
// did not get to the requested time yet.
// go to the next chronological event on all tracks
if ( !GoToNextEvent() )
{
// there is no more events to go to
break;
}
}
}
}