void LfoController::updateValueBuffer()
{
m_phaseOffset = m_phaseModel.value() / 360.0;
float * values = m_valueBuffer.values();
float phase = m_currentPhase + m_phaseOffset;
// roll phase up until we're in sync with period counter
m_bufferLastUpdated++;
if( m_bufferLastUpdated < s_periods )
{
int diff = s_periods - m_bufferLastUpdated;
phase += static_cast<float>( engine::framesPerTick() * diff ) / m_duration;
m_bufferLastUpdated += diff;
}
for( int i = 0; i < m_valueBuffer.length(); i++ )
{
const float currentSample = m_sampleFunction != NULL
? m_sampleFunction( phase )
: m_userDefSampleBuffer->userWaveSample( phase );
values[i] = qBound( 0.0f, m_baseModel.value() + ( m_amountModel.value() * currentSample / 2.0f ), 1.0f );
phase += 1.0 / m_duration;
}
m_currentPhase = absFraction( phase - m_phaseOffset );
}
// This code took forever to get right. It can
// definately be optimized.
// The code should probably be integrated with the oscillator class. But I
// don't know how to use oscillator because it is so confusing
float LfoController::value( int _offset )
{
int frame = runningFrames() + _offset + m_phaseCorrection;
//If the song is playing, sync the value with the time of the song.
if( engine::getSong()->isPlaying() || engine::getSong()->isExporting() )
{
// The new duration in frames
// (Samples/Second) / (periods/second) = (Samples/cycle)
float newDurationF =
engine::mixer()->processingSampleRate() *
m_speedModel.value();
switch(m_multiplierModel.value() )
{
case 1:
newDurationF /= 100.0;
break;
case 2:
newDurationF *= 100.0;
break;
default:
break;
}
m_phaseOffset = qRound(
m_phaseModel.value() * newDurationF / 360.0 );
int newDuration = static_cast<int>( newDurationF );
m_phaseCorrection = static_cast<int>(engine::getSong()->getTicks()*engine::framesPerTick())%newDuration
+ m_phaseOffset;
// re-run the first calculation again
frame = m_phaseCorrection + _offset;
}
// speedModel 0..1 fast..slow 0ms..20000ms
// duration m_duration
//
// frames / (20seconds of frames)
float sampleFrame = float( frame+m_phaseOffset ) /
(engine::mixer()->processingSampleRate() * m_speedModel.value() );
switch(m_multiplierModel.value() )
{
case 1:
sampleFrame *= 100.0;
break;
case 2:
sampleFrame /= 100.0;
break;
default:
break;
}
// 44100 frames/sec
return m_baseModel.value() + ( m_amountModel.value() *
( m_sampleFunction != NULL ?
m_sampleFunction(sampleFrame):
m_userDefSampleBuffer->userWaveSample(sampleFrame) )
/ 2.0f );
}
