Some attempt at improving Delay

src/Delay.cpp

@@ -27,7 +27,9 @@ struct Delay : Module {
 	DoubleRingBuffer<float, HISTORY_SIZE> historyBuffer;
 	DoubleRingBuffer<float, 16> outBuffer;
 	SampleRateConverter<1> src;
-	float lastIndex = 0.0;
+	float lastWet = 0.0;
+	RCFilter lowpassFilter;
+	RCFilter highpassFilter;
 
 	Delay();
 
@@ -42,39 +44,69 @@ Delay::Delay() {
 }
 
 void Delay::step() {
-	// Compute delay time
+	// Get input to delay block
+	float in = getf(inputs[IN_INPUT]);
+	float feedback = clampf(params[FEEDBACK_PARAM] + getf(inputs[FEEDBACK_INPUT]) / 10.0, 0.0, 0.99);
+	float dry = in + lastWet * feedback;
+
+	// Compute delay time in seconds
 	float delay = 1e-3 * powf(10.0 / 1e-3, clampf(params[TIME_PARAM] + getf(inputs[TIME_INPUT]) / 10.0, 0.0, 1.0));
+	// Number of delay samples
 	float index = delay * gSampleRate;
-	// lastIndex = crossf(lastIndex, index, 0.001);
 
-	// Read the history
-	int consume = (int)(historyBuffer.size() - index);
+	// TODO This is a horrible digital delay algorithm. Rewrite later.
+
+	// Push dry sample into history buffer
+	if (!historyBuffer.full()) {
+		historyBuffer.push(dry);
+	}
+
+	// How many samples do we need consume to catch up?
+	float consume = index - historyBuffer.size();
+	// printf("%f\t%d\t%f\n", index, historyBuffer.size(), consume);
+
 	// printf("wanted: %f\tactual: %d\tdiff: %d\tratio: %f\n", index, historyBuffer.size(), consume, index / historyBuffer.size());
 	if (outBuffer.empty()) {
-		if (consume > 0) {
-			int inFrames = consume;
-			int outFrames = outBuffer.capacity();
-			// printf("\t%d\t%d\n", inFrames, outFrames);
-			src.setRatioSmooth(index / historyBuffer.size());
-			src.process((const Frame<1>*)historyBuffer.startData(), &inFrames, (Frame<1>*)outBuffer.endData(), &outFrames);
-			historyBuffer.startIncr(inFrames);
-			outBuffer.endIncr(outFrames);
-			// printf("\t%d\t%d\n", inFrames, outFrames);
-			// if (historyBuffer.size() >= index)
-			// 	outBuffer.push(historyBuffer.shift());
-		}
+		// Idk wtf I'm doing
+		double ratio = 1.0;
+		if (consume <= -16)
+			ratio = 0.5;
+		else if (consume >= 16)
+			ratio = 2.0;
+
+		// printf("%f\t%lf\n", consume, ratio);
+		int inFrames = mini(historyBuffer.size(), 16);
+		int outFrames = outBuffer.capacity();
+		// printf(">\t%d\t%d\n", inFrames, outFrames);
+		src.setRatioSmooth(ratio);
+		src.process((const Frame<1>*)historyBuffer.startData(), &inFrames, (Frame<1>*)outBuffer.endData(), &outFrames);
+		historyBuffer.startIncr(inFrames);
+		outBuffer.endIncr(outFrames);
+		// printf("<\t%d\t%d\n", inFrames, outFrames);
+		// printf("====================================\n");
 	}
 
-	float out = 0.0;
+	float wet = 0.0;
 	if (!outBuffer.empty()) {
-		out = outBuffer.shift();
+		wet = outBuffer.shift();
 	}
 
-	// Write the history
-	float in = getf(inputs[IN_INPUT]);
-	historyBuffer.push(in + out * clampf(params[FEEDBACK_PARAM] + getf(inputs[FEEDBACK_INPUT]) / 10.0, 0.0, 1.0));
-	out = crossf(in, out, clampf(params[MIX_PARAM] + getf(inputs[MIX_INPUT]) / 10.0, 0.0, 1.0));
-
+	// Apply color to delay wet output
+	// TODO Make it sound better
+	float color = clampf(params[COLOR_PARAM] + getf(inputs[COLOR_INPUT]) / 10.0, 0.0, 1.0);
+	float lowpassFreq = 10000.0 * powf(10.0, clampf(2.0*color, 0.0, 1.0));
+	lowpassFilter.setCutoff(lowpassFreq / gSampleRate);
+	lowpassFilter.process(wet);
+	wet = lowpassFilter.lowpass();
+	float highpassFreq = 10.0 * powf(100.0, clampf(2.0*color - 1.0, 0.0, 1.0));
+	highpassFilter.setCutoff(highpassFreq / gSampleRate);
+	highpassFilter.process(wet);
+	wet = highpassFilter.highpass();
+
+	lastWet = wet;
+
+	float mix = clampf(params[MIX_PARAM] + getf(inputs[MIX_INPUT]) / 10.0, 0.0, 1.0);
+	float out = crossf(in, wet, mix);
 	setf(outputs[OUT_OUTPUT], out);
 }
 
@@ -98,7 +130,7 @@ DelayWidget::DelayWidget() {
 
 	addParam(createParam<Davies1900hBlackKnob>(Vec(67, 57), module, Delay::TIME_PARAM, 0.0, 1.0, 0.5));
 	addParam(createParam<Davies1900hBlackKnob>(Vec(67, 123), module, Delay::FEEDBACK_PARAM, 0.0, 1.0, 0.5));
-	addParam(createParam<Davies1900hBlackKnob>(Vec(67, 190), module, Delay::COLOR_PARAM, -1.0, 1.0, 0.0));
+	addParam(createParam<Davies1900hBlackKnob>(Vec(67, 190), module, Delay::COLOR_PARAM, 0.0, 1.0, 0.5));
 	addParam(createParam<Davies1900hBlackKnob>(Vec(67, 257), module, Delay::MIX_PARAM, 0.0, 1.0, 0.5));
 
 	addInput(createInput<PJ301MPort>(Vec(14, 63), module, Delay::TIME_INPUT));

src/Scope.cpp

@@ -40,6 +40,28 @@ struct Scope : Module {
 
 	Scope();
 	void step();
+
+	json_t *toJson() {
+		json_t *rootJ = json_object();
+		json_object_set_new(rootJ, "sum", json_integer((int) sum));
+		json_object_set_new(rootJ, "ext", json_integer((int) ext));
+		return rootJ;
+	}
+
+	void fromJson(json_t *rootJ) {
+		json_t *sumJ = json_object_get(rootJ, "sum");
+		if (sumJ)
+			sum = json_integer_value(sumJ);
+
+		json_t *extJ = json_object_get(rootJ, "ext");
+		if (extJ)
+			ext = json_integer_value(extJ);
+	}
+
+	void initialize() {
+		sum = false;
+		ext = false;
+	}
 };
 
 

src/VCMixer.cpp

@@ -70,9 +70,9 @@ VCMixerWidget::VCMixerWidget() {
 	addChild(createScrew<ScrewSilver>(Vec(box.size.x-30, 365)));
 
 	addParam(createParam<Davies1900hLargeBlackKnob>(Vec(48, 55), module, VCMixer::MIX_PARAM, 0.0, 1.0, 0.5));
-	addParam(createParam<Davies1900hBlackKnob>(Vec(57, 139), module, VCMixer::CH1_PARAM, 0.0, 1.0, 0.5));
-	addParam(createParam<Davies1900hBlackKnob>(Vec(57, 219), module, VCMixer::CH2_PARAM, 0.0, 1.0, 0.5));
-	addParam(createParam<Davies1900hBlackKnob>(Vec(57, 300), module, VCMixer::CH3_PARAM, 0.0, 1.0, 0.5));
+	addParam(createParam<Davies1900hBlackKnob>(Vec(57, 139), module, VCMixer::CH1_PARAM, 0.0, 1.0, 0.0));
+	addParam(createParam<Davies1900hBlackKnob>(Vec(57, 219), module, VCMixer::CH2_PARAM, 0.0, 1.0, 0.0));
+	addParam(createParam<Davies1900hBlackKnob>(Vec(57, 300), module, VCMixer::CH3_PARAM, 0.0, 1.0, 0.0));
 
 	addInput(createInput<PJ301MPort>(Vec(16, 69), module, VCMixer::MIX_CV_INPUT));
 	addInput(createInput<PJ301MPort>(Vec(22, 129), module, VCMixer::CH1_INPUT));