Refactor Effect processing

include/AudioEngine.h

@@ -50,14 +50,15 @@ class AudioPort;
 class AudioEngineWorkerThread;
 
 
-const fpp_t MINIMUM_BUFFER_SIZE = 32;
-const fpp_t DEFAULT_BUFFER_SIZE = 256;
+constexpr fpp_t MINIMUM_BUFFER_SIZE = 32;
+constexpr fpp_t DEFAULT_BUFFER_SIZE = 256;
+constexpr fpp_t MAXIMUM_BUFFER_SIZE = 4096;
 
-const int BYTES_PER_SAMPLE = sizeof( sample_t );
-const int BYTES_PER_INT_SAMPLE = sizeof( int_sample_t );
-const int BYTES_PER_FRAME = sizeof( SampleFrame );
+constexpr int BYTES_PER_SAMPLE = sizeof(sample_t);
+constexpr int BYTES_PER_INT_SAMPLE = sizeof(int_sample_t);
+constexpr int BYTES_PER_FRAME = sizeof(SampleFrame);
 
-const float OUTPUT_SAMPLE_MULTIPLIER = 32767.0f;
+constexpr float OUTPUT_SAMPLE_MULTIPLIER = 32767.0f;
 
 class LMMS_EXPORT AudioEngine : public QObject
 {

include/DummyEffect.h

@@ -98,6 +98,7 @@ class DummyEffect : public Effect
 		m_originalPluginData( originalPluginData )
 	{
 		setName();
+		setDontRun(true);
 	}
 
 	~DummyEffect() override = default;
@@ -107,9 +108,9 @@ class DummyEffect : public Effect
 		return &m_controls;
 	}
 
-	bool processAudioBuffer( SampleFrame*, const fpp_t ) override
+	ProcessStatus processImpl(SampleFrame*, const fpp_t) override
 	{
-		return false;
+		return ProcessStatus::Sleep;
 	}
 
 	const QDomElement& originalPluginData() const

include/Effect.h

@@ -63,9 +63,8 @@ class LMMS_EXPORT Effect : public Plugin
 		return "effect";
 	}
 
-
-	virtual bool processAudioBuffer( SampleFrame* _buf,
-						const fpp_t _frames ) = 0;
+	//! Returns true if audio was processed and should continue being processed
+	bool processAudioBuffer(SampleFrame* buf, const fpp_t frames);
 
 	inline ch_cnt_t processorCount() const
 	{
@@ -174,14 +173,29 @@ class LMMS_EXPORT Effect : public Plugin
 
 
 protected:
+	enum class ProcessStatus
+	{
+		//! Unconditionally continue processing
+		Continue,
+
+		//! Calculate the RMS out sum and call `checkGate` to determine whether to stop processing
+		ContinueIfNotQuiet,
+
+		//! Do not continue processing
+		Sleep
+	};
+
 	/**
-		Effects should call this at the end of audio processing
+	 * The main audio processing method that runs when plugin is not asleep
+	 */
+	virtual ProcessStatus processImpl(SampleFrame* buf, const fpp_t frames) = 0;
+
+	/**
+	 * Optional method that runs when plugin is sleeping (not enabled,
+	 * not running, not in the Okay state, or in the Don't Run state)
+	 */
+	virtual void processBypassedImpl() {}
 
-		If the setting "Keep effects running even without input" is disabled,
-		after "decay" ms of a signal below "gate", the effect is turned off
-		and won't be processed again until it receives new audio input
-	*/
-	void checkGate( double _out_sum );
 
 	gui::PluginView* instantiateView( QWidget * ) override;
 
@@ -212,6 +226,14 @@ class LMMS_EXPORT Effect : public Plugin
 
 
 private:
+	/**
+		If the setting "Keep effects running even without input" is disabled,
+		after "decay" ms of a signal below "gate", the effect is turned off
+		and won't be processed again until it receives new audio input
+	*/
+	void checkGate(double outSum);
+
+
 	EffectChain * m_parent;
 	void resample( int _i, const SampleFrame* _src_buf,
 					sample_rate_t _src_sr,

plugins/Amplifier/Amplifier.cpp

@@ -57,11 +57,8 @@ AmplifierEffect::AmplifierEffect(Model* parent, const Descriptor::SubPluginFeatu
 }
 
 
-bool AmplifierEffect::processAudioBuffer(SampleFrame* buf, const fpp_t frames)
+Effect::ProcessStatus AmplifierEffect::processImpl(SampleFrame* buf, const fpp_t frames)
 {
-	if (!isEnabled() || !isRunning()) { return false ; }
-
-	double outSum = 0.0;
 	const float d = dryLevel();
 	const float w = wetLevel();
 
@@ -86,13 +83,9 @@ bool AmplifierEffect::processAudioBuffer(SampleFrame* buf, const fpp_t frames)
 
 		// Dry/wet mix
 		currentFrame = currentFrame * d + s * w;
-
-		outSum += currentFrame.sumOfSquaredAmplitudes();
 	}
 
-	checkGate(outSum / frames);
-
-	return isRunning();
+	return ProcessStatus::ContinueIfNotQuiet;
 }
 
 

plugins/Amplifier/Amplifier.h

@@ -37,7 +37,8 @@ class AmplifierEffect : public Effect
 public:
 	AmplifierEffect(Model* parent, const Descriptor::SubPluginFeatures::Key* key);
 	~AmplifierEffect() override = default;
-	bool processAudioBuffer(SampleFrame* buf, const fpp_t frames) override;
+
+	ProcessStatus processImpl(SampleFrame* buf, const fpp_t frames) override;
 
 	EffectControls* controls() override
 	{

plugins/BassBooster/BassBooster.cpp

@@ -69,12 +69,8 @@ BassBoosterEffect::BassBoosterEffect( Model* parent, const Descriptor::SubPlugin
 
 
 
-bool BassBoosterEffect::processAudioBuffer( SampleFrame* buf, const fpp_t frames )
+Effect::ProcessStatus BassBoosterEffect::processImpl(SampleFrame* buf, const fpp_t frames)
 {
-	if( !isEnabled() || !isRunning () )
-	{
-		return( false );
-	}
 	// check out changed controls
 	if( m_frequencyChangeNeeded || m_bbControls.m_freqModel.isValueChanged() )
 	{
@@ -87,7 +83,6 @@ bool BassBoosterEffect::processAudioBuffer( SampleFrame* buf, const fpp_t frames
 	const float const_gain = m_bbControls.m_gainModel.value();
 	const ValueBuffer *gainBuffer = m_bbControls.m_gainModel.valueBuffer();
 
-	double outSum = 0.0;
 	const float d = dryLevel();
 	const float w = wetLevel();
 
@@ -102,13 +97,9 @@ bool BassBoosterEffect::processAudioBuffer( SampleFrame* buf, const fpp_t frames
 
 		// Dry/wet mix
 		currentFrame = currentFrame * d + s * w;
-
-		outSum += currentFrame.sumOfSquaredAmplitudes();
 	}
 
-	checkGate( outSum / frames );
-
-	return isRunning();
+	return ProcessStatus::ContinueIfNotQuiet;
 }
 
 

plugins/BassBooster/BassBooster.h

@@ -38,7 +38,8 @@ class BassBoosterEffect : public Effect
 public:
 	BassBoosterEffect( Model* parent, const Descriptor::SubPluginFeatures::Key* key );
 	~BassBoosterEffect() override = default;
-	bool processAudioBuffer( SampleFrame* buf, const fpp_t frames ) override;
+
+	ProcessStatus processImpl(SampleFrame* buf, const fpp_t frames) override;
 
 	EffectControls* controls() override
 	{

plugins/Bitcrush/Bitcrush.cpp

@@ -100,13 +100,8 @@ inline float BitcrushEffect::noise( float amt )
 	return fastRandf( amt * 2.0f ) - amt;
 }
 
-bool BitcrushEffect::processAudioBuffer( SampleFrame* buf, const fpp_t frames )
+Effect::ProcessStatus BitcrushEffect::processImpl(SampleFrame* buf, const fpp_t frames)
 {
-	if( !isEnabled() || !isRunning () )
-	{
-		return( false );
-	}
-
 	// update values
 	if( m_needsUpdate || m_controls.m_rateEnabled.isValueChanged() )
 	{
@@ -222,7 +217,6 @@ bool BitcrushEffect::processAudioBuffer( SampleFrame* buf, const fpp_t frames )
 
 	// now downsample and write it back to main buffer
 
-	double outSum = 0.0;
 	const float d = dryLevel();
 	const float w = wetLevel();
 	for (auto f = std::size_t{0}; f < frames; ++f)
@@ -236,12 +230,9 @@ bool BitcrushEffect::processAudioBuffer( SampleFrame* buf, const fpp_t frames )
 		}
 		buf[f][0] = d * buf[f][0] + w * qBound( -m_outClip, lsum, m_outClip ) * m_outGain;
 		buf[f][1] = d * buf[f][1] + w * qBound( -m_outClip, rsum, m_outClip ) * m_outGain;
-		outSum += buf[f][0]*buf[f][0] + buf[f][1]*buf[f][1];
 	}
 
-	checkGate( outSum / frames );
-
-	return isRunning();
+	return ProcessStatus::ContinueIfNotQuiet;
 }
 
 

plugins/Bitcrush/Bitcrush.h

@@ -41,13 +41,14 @@ class BitcrushEffect : public Effect
 public:
 	BitcrushEffect( Model* parent, const Descriptor::SubPluginFeatures::Key* key );
 	~BitcrushEffect() override;
-	bool processAudioBuffer( SampleFrame* buf, const fpp_t frames ) override;
+
+	ProcessStatus processImpl(SampleFrame* buf, const fpp_t frames) override;
 
 	EffectControls* controls() override
 	{
 		return &m_controls;
 	}
-	
+
 private:
 	void sampleRateChanged();
 	float depthCrush( float in );

plugins/Compressor/Compressor.cpp

@@ -233,31 +233,10 @@ void CompressorEffect::calcMix()
 
 
 
-bool CompressorEffect::processAudioBuffer(SampleFrame* buf, const fpp_t frames)
+Effect::ProcessStatus CompressorEffect::processImpl(SampleFrame* buf, const fpp_t frames)
 {
-	if (!isEnabled() || !isRunning())
-	{
-		// Clear lookahead buffers and other values when needed
-		if (!m_cleanedBuffers)
-		{
-			m_yL[0] = m_yL[1] = COMP_NOISE_FLOOR;
-			m_gainResult[0] = m_gainResult[1] = 1;
-			m_displayPeak[0] = m_displayPeak[1] = COMP_NOISE_FLOOR;
-			m_displayGain[0] = m_displayGain[1] = COMP_NOISE_FLOOR;
-			std::fill(std::begin(m_scLookBuf[0]), std::end(m_scLookBuf[0]), COMP_NOISE_FLOOR);
-			std::fill(std::begin(m_scLookBuf[1]), std::end(m_scLookBuf[1]), COMP_NOISE_FLOOR);
-			std::fill(std::begin(m_inLookBuf[0]), std::end(m_inLookBuf[0]), 0);
-			std::fill(std::begin(m_inLookBuf[1]), std::end(m_inLookBuf[1]), 0);
-			m_cleanedBuffers = true;
-		}
-		return false;
-	}
-	else
-	{
-		m_cleanedBuffers = false;
-	}
+	m_cleanedBuffers = false;
 
-	float outSum = 0.0;
 	const float d = dryLevel();
 	const float w = wetLevel();
 
@@ -516,8 +495,6 @@ bool CompressorEffect::processAudioBuffer(SampleFrame* buf, const fpp_t frames)
 		buf[f][0] = (1 - m_mixVal) * temp1 + m_mixVal * buf[f][0];
 		buf[f][1] = (1 - m_mixVal) * temp2 + m_mixVal * buf[f][1];
 
-		outSum += buf[f][0] * buf[f][0] + buf[f][1] * buf[f][1];
-
 		if (--m_lookWrite < 0) { m_lookWrite = m_lookBufLength - 1; }
 
 		lInPeak = drySignal[0] > lInPeak ? drySignal[0] : lInPeak;
@@ -526,15 +503,30 @@ bool CompressorEffect::processAudioBuffer(SampleFrame* buf, const fpp_t frames)
 		rOutPeak = s[1] > rOutPeak ? s[1] : rOutPeak;
 	}
 
-	checkGate(outSum / frames);
 	m_compressorControls.m_outPeakL = lOutPeak;
 	m_compressorControls.m_outPeakR = rOutPeak;
 	m_compressorControls.m_inPeakL = lInPeak;
 	m_compressorControls.m_inPeakR = rInPeak;
 
-	return isRunning();
+	return ProcessStatus::ContinueIfNotQuiet;
 }
 
+void CompressorEffect::processBypassedImpl()
+{
+	// Clear lookahead buffers and other values when needed
+	if (!m_cleanedBuffers)
+	{
+		m_yL[0] = m_yL[1] = COMP_NOISE_FLOOR;
+		m_gainResult[0] = m_gainResult[1] = 1;
+		m_displayPeak[0] = m_displayPeak[1] = COMP_NOISE_FLOOR;
+		m_displayGain[0] = m_displayGain[1] = COMP_NOISE_FLOOR;
+		std::fill(std::begin(m_scLookBuf[0]), std::end(m_scLookBuf[0]), COMP_NOISE_FLOOR);
+		std::fill(std::begin(m_scLookBuf[1]), std::end(m_scLookBuf[1]), COMP_NOISE_FLOOR);
+		std::fill(std::begin(m_inLookBuf[0]), std::end(m_inLookBuf[0]), 0);
+		std::fill(std::begin(m_inLookBuf[1]), std::end(m_inLookBuf[1]), 0);
+		m_cleanedBuffers = true;
+	}
+}
 
 // Regular modulo doesn't handle negative numbers correctly.  This does.
 inline int CompressorEffect::realmod(int k, int n)

plugins/Compressor/Compressor.h

@@ -43,7 +43,9 @@ class CompressorEffect : public Effect
 public:
 	CompressorEffect(Model* parent, const Descriptor::SubPluginFeatures::Key* key);
 	~CompressorEffect() override = default;
-	bool processAudioBuffer(SampleFrame* buf, const fpp_t frames) override;
+
+	ProcessStatus processImpl(SampleFrame* buf, const fpp_t frames) override;
+	void processBypassedImpl() override;
 
 	EffectControls* controls() override
 	{

plugins/CrossoverEQ/CrossoverEQ.cpp

@@ -89,13 +89,8 @@ void CrossoverEQEffect::sampleRateChanged()
 }
 
 
-bool CrossoverEQEffect::processAudioBuffer( SampleFrame* buf, const fpp_t frames )
+Effect::ProcessStatus CrossoverEQEffect::processImpl(SampleFrame* buf, const fpp_t frames)
 {
-	if( !isEnabled() || !isRunning () )
-	{
-		return( false );
-	}
-
 	// filters update
 	if( m_needsUpdate || m_controls.m_xover12.isValueChanged() )
 	{
@@ -192,17 +187,14 @@ bool CrossoverEQEffect::processAudioBuffer( SampleFrame* buf, const fpp_t frames
 
 	const float d = dryLevel();
 	const float w = wetLevel();
-	double outSum = 0.0;
+
 	for (auto f = std::size_t{0}; f < frames; ++f)
 	{
 		buf[f][0] = d * buf[f][0] + w * m_work[f][0];
 		buf[f][1] = d * buf[f][1] + w * m_work[f][1];
-		outSum += buf[f][0] * buf[f][0] + buf[f][1] * buf[f][1];
 	}
-
-	checkGate( outSum / frames );
-
-	return isRunning();
+
+	return ProcessStatus::ContinueIfNotQuiet;
 }
 
 void CrossoverEQEffect::clearFilterHistories()

plugins/CrossoverEQ/CrossoverEQ.h

@@ -40,7 +40,8 @@ class CrossoverEQEffect : public Effect
 public:
 	CrossoverEQEffect( Model* parent, const Descriptor::SubPluginFeatures::Key* key );
 	~CrossoverEQEffect() override;
-	bool processAudioBuffer( SampleFrame* buf, const fpp_t frames ) override;
+
+	ProcessStatus processImpl(SampleFrame* buf, const fpp_t frames) override;
 
 	EffectControls* controls() override
 	{