BogaudioModules

commit 1142112a3c28379b15c474ded4788ec1f06057b8
parent 6e4202622ab37924ff524866b5c971f4bc78daa4
Author: Matt Demanett <matt@demanett.net>
Date:   Sat, 21 Apr 2018 22:30:50 -0400

Set time minimums and add linear mode to ADSR; add test.

Diffstat:
M
src/Test2.cpp
 | 
15
+++++++++++++++
M
src/Test2.hpp
 | 
8
+++++++-
M
src/dsp/envelope.cpp
 | 
23
+++++++++++++++++------
M
src/dsp/envelope.hpp
 | 
10
+++++++++-

4 files changed, 48 insertions(+), 8 deletions(-)
diff --git a/src/Test2.cpp b/src/Test2.cpp
@@ -52,6 +52,21 @@ void Test2::step() {
 		in = inputs[IN_INPUT].value;
 	}
 	outputs[OUT_OUTPUT].value = _filter.next(in);
+
+#elif ADSR_ENVELOPE
+  if (outputs[OUT_OUTPUT].active) {
+		_adsr.setSampleRate(engineGetSampleRate());
+		if (inputs[IN_INPUT].active) {
+			_trigger.process(inputs[IN_INPUT].value);
+		}
+		_adsr.setGate(_trigger.isHigh());
+		_adsr.setAttack(params[PARAM1A_PARAM].value * 10.0f);
+		_adsr.setDecay(params[PARAM1B_PARAM].value * 10.0f);
+		_adsr.setSustain(params[PARAM2A_PARAM].value);
+		_adsr.setRelease(params[PARAM2B_PARAM].value * 10.0f);
+		_adsr.setShape(params[PARAM3A_PARAM].value > 0.5f ? ADSR::LINEAR_SHAPE : ADSR::EXPONENTIAL_SHAPE);
+		outputs[OUT_OUTPUT].value = _adsr.next() * 10.0f;
+	}
 #endif
 }
 
diff --git a/src/Test2.hpp b/src/Test2.hpp
@@ -5,12 +5,15 @@
 extern Model* modelTest2;
 
 // #define COMPLEX_BIQUAD 1
-#define MULTIPOLE 1
+// #define MULTIPOLE 1
+#define ADSR_ENVELOPE 1
 
 #ifdef COMPLEX_BIQUAD
 #include "dsp/filter.hpp"
 #elif MULTIPOLE
 #include "dsp/filter.hpp"
+#elif ADSR_ENVELOPE
+#include "dsp/envelope.hpp"
 #elif
 #error what
 #endif
@@ -56,6 +59,9 @@ struct Test2 : Module {
 	MultipoleFilter _filter;
 	const int maxSteps = 10;
 	int _steps = maxSteps;
+#elif ADSR_ENVELOPE
+	ADSR _adsr;
+	SchmittTrigger _trigger;
 #endif
 
 	Test2() : Module(NUM_PARAMS, NUM_INPUTS, NUM_OUTPUTS, NUM_LIGHTS) {
diff --git a/src/dsp/envelope.cpp b/src/dsp/envelope.cpp
@@ -1,6 +1,7 @@
 #include <assert.h>
 #include <math.h>
 #include <stdio.h>
+#include <algorithm>
 
 #include "envelope.hpp"
 
@@ -26,12 +27,12 @@ void ADSR::setGate(bool high) {
 
 void ADSR::setAttack(float seconds) {
 	assert(_attack >= 0.0f);
-	_attack = seconds;
+	_attack = std::max(seconds, 0.001f);
 }
 
 void ADSR::setDecay(float seconds) {
 	assert(_decay >= 0.0f);
-	_decay = seconds;
+	_decay = std::max(seconds, 0.001f);
 }
 
 void ADSR::setSustain(float level) {
@@ -42,7 +43,11 @@ void ADSR::setSustain(float level) {
 
 void ADSR::setRelease(float seconds) {
 	assert(_release >= 0.0f);
-	_release = seconds;
+	_release = std::max(seconds, 0.001f);
+}
+
+void ADSR::setShape(Shape shape) {
+	_shape = shape;
 }
 
 float ADSR::_next() {
@@ -107,13 +112,17 @@ float ADSR::_next() {
 		case ATTACK_STAGE: {
 			_stageProgress += _sampleTime;
 			_envelope = _stageProgress / _attack;
-			_envelope = powf(_envelope, 0.5f);
+			if (_shape == EXPONENTIAL_SHAPE) {
+				_envelope = powf(_envelope, 0.5f);
+			}
 			break;
 		}
 		case DECAY_STAGE: {
 			_stageProgress += _sampleTime;
 			_envelope = _stageProgress / _decay;
-			_envelope = powf(_envelope, 0.5f);
+			if (_shape == EXPONENTIAL_SHAPE) {
+				_envelope = powf(_envelope, 0.5f);
+			}
 			_envelope *= 1.0f - _sustain;
 			_envelope = 1.0f - _envelope;
 			break;
@@ -125,7 +134,9 @@ float ADSR::_next() {
 		case RELEASE_STAGE: {
 			_stageProgress += _sampleTime;
 			_envelope = _stageProgress / _release;
-			_envelope = powf(_envelope, 0.5f);
+			if (_shape == EXPONENTIAL_SHAPE) {
+				_envelope = powf(_envelope, 0.5f);
+			}
 			_envelope *= _releaseLevel;
 			_envelope = _releaseLevel - _envelope;
 			break;
diff --git a/src/dsp/envelope.hpp b/src/dsp/envelope.hpp
@@ -30,18 +30,25 @@ struct ADSR : EnvelopeGenerator {
 		RELEASE_STAGE
 	};
 
+	enum Shape {
+		LINEAR_SHAPE,
+		EXPONENTIAL_SHAPE
+	};
+
 	Stage _stage = STOPPED_STAGE;
 	bool _gated = false;
 	float _attack = 0.0f;
 	float _decay = 0.0f;
 	float _sustain = 1.0f;
 	float _release = 0.0f;
+	Shape _shape;
 	float _stageProgress = 0.0f;
 	float _releaseLevel = 0.0f;
 	float _envelope = 0.0f;
 
-	ADSR(float sampleRate = 1000.0f)
+	ADSR(Shape shape = EXPONENTIAL_SHAPE, float sampleRate = 1000.0f)
 	: EnvelopeGenerator(sampleRate)
+	, _shape(shape)
 	{
 	}
 
@@ -51,6 +58,7 @@ struct ADSR : EnvelopeGenerator {
 	void setDecay(float seconds);
 	void setSustain(float level);
 	void setRelease(float seconds);
+	void setShape(Shape shape);
 
 	virtual float _next() override;
 };