Method play

src/tracks/SampleTrack.cpp:603–690

bool SampleTrack::play( const MidiTime & _start, const fpp_t _frames,
					const f_cnt_t _offset, int _tco_num )
{
	m_audioPort.effects()->startRunning();
	bool played_a_note = false;	// will be return variable

	tcoVector tcos;
	::BBTrack * bb_track = NULL;
	if( _tco_num >= 0 )
	{
		if( _start != 0 )
		{
			return false;
		}
		tcos.push_back( getTCO( _tco_num ) );
		if (trackContainer() == (TrackContainer*)Engine::getBBTrackContainer())
		{
			bb_track = BBTrack::findBBTrack( _tco_num );
		}
	}
	else
	{
		for( int i = 0; i < numOfTCOs(); ++i )
		{
			TrackContentObject * tco = getTCO( i );
			SampleTCO * sTco = dynamic_cast<SampleTCO*>( tco );

			if( _start >= sTco->startPosition() && _start < sTco->endPosition() )
			{
				if( sTco->isPlaying() == false )
				{
					auto bufferFramesPerTick = Engine::framesPerTick (sTco->sampleBuffer ()->sampleRate ());
					f_cnt_t sampleStart = bufferFramesPerTick * ( _start - sTco->startPosition() );

					f_cnt_t tcoFrameLength = bufferFramesPerTick * ( sTco->endPosition() - sTco->startPosition() );

					f_cnt_t sampleBufferLength = sTco->sampleBuffer()->frames();
					//if the Tco smaller than the sample length we play only until Tco end
					//else we play the sample to the end but nothing more
					f_cnt_t samplePlayLength = tcoFrameLength > sampleBufferLength ? sampleBufferLength : tcoFrameLength;
					//we only play within the sampleBuffer limits
					if( sampleStart < sampleBufferLength )
					{
						sTco->setSampleStartFrame( sampleStart );
						sTco->setSamplePlayLength( samplePlayLength );
						tcos.push_back( sTco );
						sTco->setIsPlaying( true );
					}
				}
			}
			else
			{
				sTco->setIsPlaying( false );
			}
		}
	}

	for( tcoVector::Iterator it = tcos.begin(); it != tcos.end(); ++it )