Multi-voice chorus/flanger with true stereo spread and smooth parameter handling. More...

#include <Chorus.h>

Collaboration diagram for dspark::Chorus< T >:

[legend]

Public Member Functions
	~Chorus ()=default

void	prepare (const AudioSpec &spec)
	Prepares the chorus for processing, allocating delay lines.

void	processBlock (AudioBufferView< T > buffer) noexcept
	Processes an audio block in-place.

void	reset () noexcept
	Resets delay lines and LFO phases.

void	setRate (T hz) noexcept
	Sets the LFO modulation rate.

void	setDepthMs (T ms) noexcept
	Sets the LFO modulation depth in milliseconds.

void	setMix (T dryWet) noexcept
	Sets the wet/dry mix ratio.

void	setVoices (int count) noexcept
	Sets the number of active voices per channel.

void	setFeedback (T amount) noexcept
	Sets the feedback gain.

void	setCenterDelay (T ms) noexcept
	Sets the base delay time.

void	setStereoSpread (T amount) noexcept
	Sets the stereo spread amount.

void	setAutoDepth (bool enabled) noexcept
	Couples depth to rate automatically to prevent pitch artifacts at high speeds.

void	setModWaveform (typename Oscillator< T >::Waveform wf) noexcept
	Sets the oscillator waveform for all voices.

std::vector< uint8_t >	getState () const
	Serializes the parameter state (setup/UI threads; allocates).

bool	setState (const uint8_t *data, size_t size)
	Restores parameters from a blob (tolerant; rejects foreign ids).

Static Public Attributes
static constexpr int	kMaxVoices = 4

static constexpr int	kMaxChannels = 16

Protected Member Functions
void	updateLfoPhases () noexcept
	Recalculates LFO phases for all channels and voices based on stereo spread.

Protected Attributes
AudioSpec	spec_ {}

int	maxDelaySamples_ { 0 }

std::atomic< T >	rate_ { T(1) }

std::atomic< T >	depthMs_ { T(3.5) }

std::atomic< T >	mix_ { T(0.5) }

std::atomic< T >	feedback_ { T(0) }

std::atomic< T >	centerDelayMs_ { T(7) }

std::atomic< T >	stereoSpread_ { T(0.5) }

std::atomic< int >	numVoices_ { 2 }

std::atomic< bool >	autoDepth_ { false }

T	lastSpread_ { T(0.5) }

std::atomic< typename Oscillator< T >::Waveform >	lfoWaveform_ { Oscillator<T>::Waveform::Sine }

std::atomic< bool >	lfoPhaseDirty_ { false }

std::atomic< bool >	waveformDirty_ { false }

T	smoothedCenterSamples_ { T(0) }

T	smoothedDepthSamples_ { T(0) }

std::array< RingBuffer< T >, kMaxChannels >	delayLines_ {}

std::array< std::array< Oscillator< T >, kMaxVoices >, kMaxChannels >	lfos_ {}

std::array< T, kMaxChannels >	fbState_ {}

DryWetMixer< T >	mixer_

Detailed Description

template<FloatType T>
class dspark::Chorus< T >

Multi-voice chorus/flanger with true stereo spread and smooth parameter handling.

Template Parameters

T	Sample type (float or double).

Definition at line 59 of file Chorus.h.

Constructor & Destructor Documentation

◆ ~Chorus()

template<FloatType T>

dspark::Chorus< T >::~Chorus ( )

default

Member Function Documentation

◆ getState()

template<FloatType T>

std::vector< uint8_t > dspark::Chorus< T >::getState ( ) const

inline

Serializes the parameter state (setup/UI threads; allocates).

Definition at line 358 of file Chorus.h.

◆ prepare()

template<FloatType T>

void dspark::Chorus< T >::prepare ( const AudioSpec & spec )

inline

Prepares the chorus for processing, allocating delay lines.

An invalid spec (non-positive or non-finite fields) is a no-op that keeps the previous state.

Parameters

spec	Audio environment specification (sample rate, channels).

Definition at line 77 of file Chorus.h.

◆ processBlock()

template<FloatType T>

void dspark::Chorus< T >::processBlock ( AudioBufferView< T > buffer )

inlinenoexcept

Processes an audio block in-place.

Channels beyond the prepared count pass through untouched.

Parameters

buffer Audio buffer view to process (planar layout expected).

Definition at line 117 of file Chorus.h.

◆ reset()

template<FloatType T>

void dspark::Chorus< T >::reset ( )

inlinenoexcept

Resets delay lines and LFO phases.

Definition at line 248 of file Chorus.h.

◆ setAutoDepth()

template<FloatType T>

void dspark::Chorus< T >::setAutoDepth ( bool enabled )

inlinenoexcept

Couples depth to rate automatically to prevent pitch artifacts at high speeds.

Parameters

enabled True to activate automatic depth attenuation.

Definition at line 337 of file Chorus.h.

◆ setCenterDelay()

template<FloatType T>

void dspark::Chorus< T >::setCenterDelay ( T ms )

inlinenoexcept

Sets the base delay time.

Parameters

ms	Time in milliseconds [0.1 - 30.0]. Non-finite values are ignored.

Definition at line 317 of file Chorus.h.

◆ setDepthMs()

template<FloatType T>

void dspark::Chorus< T >::setDepthMs ( T ms )

inlinenoexcept

Sets the LFO modulation depth in milliseconds.

Parameters

ms	Depth in milliseconds [0.0 - 20.0]. Non-finite values are ignored.

Definition at line 275 of file Chorus.h.

◆ setFeedback()

template<FloatType T>

void dspark::Chorus< T >::setFeedback ( T amount )

inlinenoexcept

Sets the feedback gain.

Parameters

amount Feedback from -0.99 to 0.99. Negative values yield flanger effects. Non-finite values are ignored.

Definition at line 307 of file Chorus.h.

◆ setMix()

template<FloatType T>

void dspark::Chorus< T >::setMix ( T dryWet )

inlinenoexcept

Sets the wet/dry mix ratio.

Parameters

dryWet Ratio from 0.0 (fully dry) to 1.0 (fully wet). Non-finite values are ignored.

Definition at line 286 of file Chorus.h.

◆ setModWaveform()

template<FloatType T>

void dspark::Chorus< T >::setModWaveform ( typename Oscillator< T >::Waveform wf )

inlinenoexcept

Sets the oscillator waveform for all voices.

Warning: Using Saw or Square waves for delay modulation without additional lowpass filtering will cause audible clicks. Sine or Triangle are recommended.

Parameters

wf	The desired waveform type (wild enum values clamp).

Definition at line 345 of file Chorus.h.

◆ setRate()

template<FloatType T>

void dspark::Chorus< T >::setRate ( T hz )

inlinenoexcept

Sets the LFO modulation rate.

Parameters

hz	Frequency in Hertz [0.01 - 20.0]. Non-finite values are ignored.

Definition at line 265 of file Chorus.h.

◆ setState()

template<FloatType T>

bool dspark::Chorus< T >::setState	(	const uint8_t *	data,
		size_t	size
	)

inline

Restores parameters from a blob (tolerant; rejects foreign ids).

Definition at line 375 of file Chorus.h.

◆ setStereoSpread()

template<FloatType T>

void dspark::Chorus< T >::setStereoSpread ( T amount )

inlinenoexcept

Sets the stereo spread amount.

Parameters

amount Offset ratio from 0.0 to 1.0. Non-finite values are ignored.

Definition at line 327 of file Chorus.h.

◆ setVoices()

template<FloatType T>

void dspark::Chorus< T >::setVoices ( int count )

inlinenoexcept

Sets the number of active voices per channel.

Parameters

count Voices from 1 to 4.

Definition at line 296 of file Chorus.h.

◆ updateLfoPhases()

template<FloatType T>

void dspark::Chorus< T >::updateLfoPhases ( )

template<FloatType T>

std::atomic<bool> dspark::Chorus< T >::waveformDirty_ { false }

protected

Definition at line 435 of file Chorus.h.

The documentation for this class was generated from the following file:

Effects/Chorus.h

Public Member Functions

Static Public Attributes

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ ~Chorus()

Member Function Documentation

◆ getState()

◆ prepare()

◆ processBlock()

◆ reset()

◆ setAutoDepth()

◆ setCenterDelay()

◆ setDepthMs()

◆ setFeedback()

◆ setMix()

◆ setModWaveform()

◆ setRate()

◆ setState()

◆ setStereoSpread()

◆ setVoices()

◆ updateLfoPhases()

Member Data Documentation

◆ autoDepth_

◆ centerDelayMs_

◆ delayLines_

◆ depthMs_

◆ fbState_

◆ feedback_

◆ kMaxChannels

◆ kMaxVoices

◆ lastSpread_

◆ lfoPhaseDirty_

◆ lfos_

◆ lfoWaveform_

◆ maxDelaySamples_

◆ mix_

◆ mixer_

◆ numVoices_

◆ rate_

◆ smoothedCenterSamples_

◆ smoothedDepthSamples_

◆ spec_

◆ stereoSpread_

◆ waveformDirty_