BogaudioModules

commit 403f4adb41e9023efe1dd678f8b72a2dfec87d41
parent bba382726f4f4111105fc170d50c9fc0d5d49443
Author: Matt Demanett <matt@demanett.net>
Date:   Sun, 20 May 2018 21:57:15 -0500

Additator: fix interaction of high filter with with high partial count (would yield silence).

Diffstat:
M
src/Additator.cpp
 | 
10
+++++++---
M
src/Additator.hpp
 | 
1
+
M
src/dsp/oscillator.cpp
 | 
9
++++++---
M
src/dsp/oscillator.hpp
 | 
2
+-

4 files changed, 15 insertions(+), 7 deletions(-)
diff --git a/src/Additator.cpp b/src/Additator.cpp
@@ -60,6 +60,7 @@ void Additator::step() {
 
 			float multiple = 1.0f;
 			_oscillator.setPartialFrequencyRatio(1, multiple);
+			_activePartials = 1;
 			for (int i = 2, n = _oscillator.partialCount(); i <= n; ++i) {
 				float ii = i;
 				if (i % 2 == 0) {
@@ -68,7 +69,9 @@ void Additator::step() {
 				else {
 					ii += _oddSkew;
 				}
-				_oscillator.setPartialFrequencyRatio(i, powf(ii, _width));
+				if (_oscillator.setPartialFrequencyRatio(i, powf(ii, _width))) {
+					_activePartials = i;
+				}
 			}
 		}
 
@@ -94,9 +97,10 @@ void Additator::step() {
 			float as[maxPartials + 1];
 			float total = as[1] = 1.0f;
 			filter = log10f(_filter) + 1.0f;
+			int np = std::min(_partials, _activePartials);
 			for (int i = 2, n = _oscillator.partialCount(); i <= n; ++i) {
 				as[i] = 0.0f;
-				if (i <= _partials) {
+				if (i <= np) {
 					as[i] = powf(i, -_decay) * powf(_filter, i);
 					if (i % 2 == 0) {
 						if (_balance > 0.0f) {
@@ -111,7 +115,7 @@ void Additator::step() {
 					total += as[i];
 				}
 			}
-			float norm = std::max(_partials / (float)_oscillator.partialCount(), 0.1f);
+			float norm = std::max(np / (float)_oscillator.partialCount(), 0.1f);
 			norm = 1.0f + (_amplitudeNormalization - 1.0f) * norm;
 			norm = std::max(total / norm, 0.7f);
 			for (int i = 1, n = _oscillator.partialCount(); i <= n; ++i) {
diff --git a/src/Additator.hpp b/src/Additator.hpp
@@ -81,6 +81,7 @@ struct Additator : Module {
 	float _filter = 0.0f;
 	Phase _phase = PHASE_RESET;
 	float _maxFrequency = 0.0f;
+	int _activePartials = 1;
 	SineBankOscillator _oscillator;
 	PositiveZeroCrossing _syncTrigger;
 	SlewLimiter _widthSL;
diff --git a/src/dsp/oscillator.cpp b/src/dsp/oscillator.cpp
@@ -230,13 +230,16 @@ void SineBankOscillator::setPartial(int i, float frequencyRatio, float amplitude
 	setPartialAmplitude(i, amplitude);
 }
 
-void SineBankOscillator::setPartialFrequencyRatio(int i, float frequencyRatio) {
+bool SineBankOscillator::setPartialFrequencyRatio(int i, float frequencyRatio) {
 	if (i <= (int)_partials.size()) {
 		Partial& p = _partials[i - 1];
 		p.frequencyRatio = frequencyRatio;
-		p.frequency = _frequency * frequencyRatio;
-		p.sine.setFrequency((double)_frequency * (double)frequencyRatio);
+		double f = (double)_frequency * (double)frequencyRatio;
+		p.frequency = f;
+		p.sine.setFrequency(f);
+		return f < _maxPartialFrequency;
 	}
+	return false;
 }
 
 void SineBankOscillator::setPartialAmplitude(int i, float amplitude, bool envelope) {
diff --git a/src/dsp/oscillator.hpp b/src/dsp/oscillator.hpp
@@ -318,7 +318,7 @@ struct SineBankOscillator : Oscillator {
 
 	// one-based indexes.
 	void setPartial(int i, float frequencyRatio, float amplitude);
-	void setPartialFrequencyRatio(int i, float frequencyRatio);
+	bool setPartialFrequencyRatio(int i, float frequencyRatio);
 	void setPartialAmplitude(int i, float amplitude, bool envelope = false);
 
 	void syncToPhase(float phase);