@ -2,17 +2,22 @@
# include <cmath> # include <cmath>
Flanger : : Flanger ( float32_t sampling_rate , float32_t delay_time , float32_t frequency , float32_t depth , float32_t feedback ) : Flanger : : Flanger ( float32_t sampling_rate , float32_t rate , float32_t depth , float32_t feedback ) :
FXElement ( sampling_rate ) , FXElement ( sampling_rate ) ,
MaxDelayLineSize ( static_cast < unsigned > ( 2.0f * MAX_FLANGER_DELAY * sampling_rate / 1000.0f ) ) , MaxDelayLineSize ( static_cast < unsigned > ( MAX_FLANGER_DELAY * sampling_rate ) ) ,
delay_line_index_ ( 0 ) , write_index_ ( 0 )
lfo_ ( sampling_rate , LFO : : Waveform : : Sine , 0.1f , 10.0f )
{ {
this - > delay_lineL_ = new float32_t [ this - > MaxDelayLineSize ] ; this - > delay_lineL_ = new float32_t [ this - > MaxDelayLineSize ] ;
this - > delay_lineR_ = new float32_t [ this - > MaxDelayLineSize ] ; this - > delay_lineR_ = new float32_t [ this - > MaxDelayLineSize ] ;
this - > setDelayTime ( delay_time ) ; memset ( this - > delay_lineL_ , 0 , this - > MaxDelayLineSize * sizeof ( float32_t ) ) ;
this - > setFrequency ( frequency ) ; memset ( this - > delay_lineR_ , 0 , this - > MaxDelayLineSize * sizeof ( float32_t ) ) ;
memset ( this - > feedback_samples_ , 0 , 2 * sizeof ( float32_t ) ) ;
this - > lfo_ [ LFO_Index : : LFO_L ] = new LFO ( sampling_rate , LFO : : Waveform : : Sine , 0.1f , 5.0f ) ;
this - > lfo_ [ LFO_Index : : LFO_R ] = new LFO ( sampling_rate , LFO : : Waveform : : Sine , 0.1f , 5.0f , Constants : : MPI_2 ) ;
this - > setRate ( rate ) ;
this - > setDepth ( depth ) ; this - > setDepth ( depth ) ;
this - > setFeedback ( feedback ) ; this - > setFeedback ( feedback ) ;
} }
@ -21,52 +26,96 @@ Flanger::~Flanger()
{ {
delete [ ] this - > delay_lineL_ ; delete [ ] this - > delay_lineL_ ;
delete [ ] this - > delay_lineR_ ; delete [ ] this - > delay_lineR_ ;
delete this - > lfo_ [ LFO_Index : : LFO_L ] ;
delete this - > lfo_ [ LFO_Index : : LFO_R ] ;
}
inline float32_t linearIterpolationnterp ( float32_t inX , float32_t inY , float32_t inPhase )
{
return ( 1.0f - inPhase ) * inX + inPhase * inY ;
} }
void Flanger : : processSample ( float32_t inL , float32_t inR , float32_t & outL , float32_t & outR ) void Flanger : : processSample ( float32_t inL , float32_t inR , float32_t & outL , float32_t & outR )
{ {
// Calculate the delay time based on the depth and rate parameters
// Write sample and any feedback into delay buffers
float32_t delay = this - > getDelayTime ( ) + this - > getDepth ( ) * this - > lfo_ . process ( ) ; this - > delay_lineL_ [ this - > write_index_ ] = inL + this - > feedback_samples_ [ 0 ] ;
this - > delay_lineR_ [ this - > write_index_ ] = inR + this - > feedback_samples_ [ 1 ] ;
// Convert the delay time to samples
+ + this - > write_index_ ;
unsigned delay_samples = static_cast < unsigned > ( delay * this - > getSamplingRate ( ) / 1000.0f ) ; if ( this - > write_index_ > = this - > MaxDelayLineSize )
{
this - > write_index_ - = this - > MaxDelayLineSize ;
}
// mix the input audio with the delayed audio and the feedback signal
// Configure LFO for effect processing
outL = inL + this - > delay_lineL_ [ ( this - > delay_line_index_ + this - > delay_line_size_ - delay_samples ) % this - > delay_line_size_ ] * ( 1.0 - this - > getFeedback ( ) ) ; float32_t lfo_l = this - > lfo_ [ LFO_L ] - > process ( ) * this - > depth_ ;
outR = inR + this - > delay_lineR_ [ ( this - > delay_line_index_ + this - > delay_line_size_ - delay_samples ) % this - > delay_line_size_ ] * ( 1.0 - this - > getFeedback ( ) ) ; float32_t lfo_r = this - > lfo_ [ LFO_R ] - > process ( ) * this - > depth_ ;
// Update the delay buffer with the mixed audio and the feedback signal
// Map LFO range to millisecond range according to Chorus or Flanger effect
this - > delay_lineL_ [ this - > delay_line_index_ ] = inL + outL * this - > getFeedback ( ) ; float32_t lfoMappedL = mapfloat ( lfo_l , - 1.0f , 1.0f , 0.001f , 0.005f ) ;
this - > delay_lineR_ [ this - > delay_line_index_ ] = inR + outR * this - > getFeedback ( ) ; float32_t lfoMappedR = mapfloat ( lfo_r , - 1.0f , 1.0f , 0.001f , 0.005f ) ;
this - > delay_line_index_ = ( this - > delay_line_index_ + 1 ) % this - > delay_line_size_ ; // Calculate delay lengths in samples
float32_t delayTimeSamplesL = this - > getSamplingRate ( ) * lfoMappedL ;
float32_t delayTimeSamplesR = this - > getSamplingRate ( ) * lfoMappedR ;
// Calculate read head positions
float32_t delayReadHeadL = this - > write_index_ - delayTimeSamplesL ;
if ( delayReadHeadL < 0.0f )
{
delayReadHeadL + = this - > MaxDelayLineSize ;
}
float32_t delayReadHeadR = this - > write_index_ - delayTimeSamplesR ;
if ( delayReadHeadR < 0.0f )
{
delayReadHeadR + = this - > MaxDelayLineSize ;
} }
void Flanger : : setDelayTime ( float32_t delayMS ) // Calculate linear interpolation point for left channel
int currentL = ( int ) delayReadHeadL ;
int nextL = currentL + 1 ;
float32_t fractionL = delayReadHeadL - currentL ;
if ( nextL > = static_cast < int > ( this - > MaxDelayLineSize ) )
{ {
this - > delay_time_ms_ = constrain ( delayMS , 1.0f , MAX_FLANGER_DELAY ) ; nextL - = this - > MaxDelayLineSize ;
this - > adjustDelayCofficients ( ) ;
} }
float32_t Flanger : : getDelayTime ( ) const // Calculate linear interpolation point for right channel
int currentR = ( int ) delayReadHeadR ;
int nextR = currentR + 1 ;
float32_t fractionR = delayReadHeadR - currentR ;
if ( nextR > = static_cast < int > ( this - > MaxDelayLineSize ) )
{ {
return this - > delay_time_ms_ ; nextR - = this - > MaxDelayLineSize ;
} }
void Flanger : : setFrequency ( float32_t frequency ) // Interpolate and read from delay buffer
float32_t delay_sample_l = linearIterpolationnterp ( this - > delay_lineL_ [ currentL ] , this - > delay_lineL_ [ nextL ] , fractionL ) ;
float32_t delay_sample_r = linearIterpolationnterp ( this - > delay_lineR_ [ currentR ] , this - > delay_lineR_ [ nextR ] , fractionR ) ;
// Store delayed samples as feedback
this - > feedback_samples_ [ 0 ] = delay_sample_l * this - > feedback_ ;
this - > feedback_samples_ [ 1 ] = delay_sample_r * this - > feedback_ ;
outL = delay_sample_l ;
outR = delay_sample_r ;
}
void Flanger : : setRate ( float32_t rate )
{ {
this - > lfo_ . setNormalizedFrequency ( frequency ) ; this - > lfo_ [ LFO_Index : : LFO_L ] - > setNormalizedFrequency ( rate ) ;
this - > lfo_ [ LFO_Index : : LFO_R ] - > setNormalizedFrequency ( rate ) ;
} }
float32_t Flanger : : getFrequency ( ) const float32_t Flanger : : getRate ( ) const
{ {
return this - > lfo_ . getNormalizedFrequency ( ) ; return this - > lfo_ [ LFO_Index : : LFO_L ] - > getNormalizedFrequency ( ) ;
} }
void Flanger : : setDepth ( float32_t depth ) void Flanger : : setDepth ( float32_t depth )
{ {
this - > depth_ = constrain ( depth , 0.0f , MAX_FLANGER_DELAY ) ; this - > depth_ = constrain ( depth , 0.0f , 1.0f ) ;
this - > adjustDelayCofficients ( ) ;
} }
float32_t Flanger : : getDepth ( ) const float32_t Flanger : : getDepth ( ) const
@ -76,15 +125,10 @@ float32_t Flanger::getDepth() const
void Flanger : : setFeedback ( float32_t feedback ) void Flanger : : setFeedback ( float32_t feedback )
{ {
this - > feedback_ = constrain ( feedback , 0.0f , 1.0 f) ; this - > feedback_ = constrain ( feedback , 0.0f , 0.97 f) ;
} }
float32_t Flanger : : getFeedback ( ) const float32_t Flanger : : getFeedback ( ) const
{ {
return this - > feedback_ ; return this - > feedback_ ;
} }
void Flanger : : adjustDelayCofficients ( )
{
this - > delay_line_size_ = static_cast < unsigned > ( this - > getSamplingRate ( ) * ( this - > getDelayTime ( ) + this - > getDepth ( ) ) / 1000.0f ) ;
}
abscisys
3 years ago