Add param smoothing when moving Knob

include/app/ParamQuantity.hpp

@@ -12,15 +12,12 @@ namespace rack {
 struct ParamQuantity : Quantity {
 	Module *module = NULL;
 	int paramId = 0;
-	/** Use engine smoothing of Param values */
-	bool smooth = false;
-	/** Snap to the nearest integer */
-	bool snap = false;
-	float snapValue = 0.f;
 
 	Param *getParam();
 	ParamInfo *getParamInfo();
-	void commitSnap();
+	/** Request to the engine to smoothly set the value */
+	void setSmoothValue(float smoothValue);
+	float getSmoothValue();
 
 	void setValue(float value) override;
 	float getValue() override;

include/app/ParamWidget.hpp

@@ -13,6 +13,7 @@ struct ParamWidget : OpaqueWidget {
 	ParamQuantity *paramQuantity = NULL;
 	float dirtyValue = NAN;
 	Tooltip *tooltip = NULL;
+	bool snap = false;
 
 	~ParamWidget();
 	void step() override;

include/engine/Engine.hpp

@@ -34,7 +34,9 @@ struct Engine {
 	void addCable(Cable *cable);
 	void removeCable(Cable *cable);
 	void setParam(Module *module, int paramId, float value);
-	void setParamSmooth(Module *module, int paramId, float value);
+	float getParam(Module *module, int paramId);
+	void setSmoothParam(Module *module, int paramId, float value);
+	float getSmoothParam(Module *module, int paramId);
 	int getNextModuleId();
 
 	void setSampleRate(float sampleRate);

include/engine/ParamInfo.hpp

@@ -15,10 +15,9 @@ struct ParamQuantityFactory {
 
 
 struct ParamInfo {
-	// For formatting/displaying the value
-	/** Set to 0 for linear, nonzero for exponential */
 	std::string label;
 	std::string unit;
+	/** Set to 0 for linear, nonzero for exponential */
 	float displayBase = 0.f;
 	float displayMultiplier = 1.f;
 	std::string description;

src/app/Knob.cpp

@@ -58,7 +58,8 @@ void Knob::onDragMove(const event::DragMove &e) {
 		// Drag slower if Mod is held
 		if (app()->window->isModPressed())
 			delta /= 16.f;
-		paramQuantity->moveValue(delta);
+		float oldValue = paramQuantity->getSmoothValue();
+		paramQuantity->setSmoothValue(oldValue + delta);
 	}
 
 	ParamWidget::onDragMove(e);

src/app/ParamQuantity.cpp

@@ -1,4 +1,6 @@
 #include "app/ParamQuantity.hpp"
+#include "app.hpp"
+#include "engine/Engine.hpp"
 
 
 namespace rack {
@@ -14,8 +16,15 @@ ParamInfo *ParamQuantity::getParamInfo() {
 	return &module->paramInfos[paramId];
 }
 
-void ParamQuantity::commitSnap() {
-	// TODO
+void ParamQuantity::setSmoothValue(float smoothValue) {
+	if (!module)
+		return;
+	smoothValue = math::clamp(smoothValue, getMinValue(), getMaxValue());
+	app()->engine->setSmoothParam(module, paramId, smoothValue);
+}
+
+float ParamQuantity::getSmoothValue() {
+	return app()->engine->getSmoothParam(module, paramId);
 }
 
 void ParamQuantity::setValue(float value) {

src/engine/Engine.cpp

@@ -348,7 +348,11 @@ void Engine::setParam(Module *module, int paramId, float value) {
 	module->params[paramId].value = value;
 }
 
-void Engine::setParamSmooth(Module *module, int paramId, float value) {
+float Engine::getParam(Module *module, int paramId) {
+	return module->params[paramId].value;
+}
+
+void Engine::setSmoothParam(Module *module, int paramId, float value) {
 	// If another param is being smoothed, jump value
 	if (internal->smoothModule && !(internal->smoothModule == module && internal->smoothParamId == paramId)) {
 		internal->smoothModule->params[internal->smoothParamId].value = internal->smoothValue;
@@ -358,6 +362,12 @@ void Engine::setParamSmooth(Module *module, int paramId, float value) {
 	internal->smoothModule = module;
 }
 
+float Engine::getSmoothParam(Module *module, int paramId) {
+	if (internal->smoothModule == module && internal->smoothParamId == paramId)
+		return internal->smoothValue;
+	return getParam(module, paramId);
+}
+
 int Engine::getNextModuleId() {
 	return internal->nextModuleId++;
 }