filter refactor (not working yet)

Author: tesselode

source/Filter.cpp

@@ -45,17 +45,10 @@ double StateVariableFilter::Process(double dt, double input, double cutoff, bool
 	return highPass ? high : low;
 }
 
-void MultiFilter::UpdateFilterMixes(double dt)
-{
-	filter1Mix += ((mode == FilterModes::onePole ? 1.0 : 0.0) - filter1Mix) * 100.0 * dt;
-	filter2Mix += ((mode == FilterModes::twoPole ? 1.0 : 0.0) - filter2Mix) * 100.0 * dt;
-	filter4Mix += ((mode == FilterModes::fourPole ? 1.0 : 0.0) - filter4Mix) * 100.0 * dt;
-	filterSvfMix += ((mode == FilterModes::stateVariable ? 1.0 : 0.0) - filterSvfMix) * 100.0 * dt;
-}
-
 void MultiFilter::Process(double dt, double & l, double & r, double cutoff, bool highPass)
 {
-	UpdateFilterMixes(dt);
+	for (int i = 0; i < std::size(mix); i++)
+		mix[i] += ((mode == i ? 1.0 : 0.0) - mix[i]) * 100.0 * dt;
 
 	auto inL = l;
 	auto inR = r;
@@ -64,19 +57,10 @@ void MultiFilter::Process(double dt, double & l, double & r, double cutoff, bool
 	l = 0.0;
 	r = 0.0;
 
-	filter1.Process(dt, inL, inR, cutoff, tempOutL, tempOutR, highPass);
-	l += tempOutL * filter1Mix;
-	r += tempOutR * filter1Mix;
-
-	filter2.Process(dt, inL, inR, cutoff, tempOutL, tempOutR, highPass);
-	l += tempOutL * filter2Mix;
-	r += tempOutR * filter2Mix;
-
-	filter4.Process(dt, inL, inR, cutoff, tempOutL, tempOutR, highPass);
-	l += tempOutL * filter4Mix;
-	r += tempOutR * filter4Mix;
-
-	filterSvf.Process(dt, inL, inR, cutoff, tempOutL, tempOutR, highPass);
-	l += tempOutL * filterSvfMix;
-	r += tempOutR * filterSvfMix;
+	for (int i = 0; i < std::size(filters); i++)
+	{
+		filters[i].Process(dt, inL, inR, cutoff, tempOutL, tempOutR, highPass);
+		l += tempOutL * mix[i];
+		r += tempOutR * mix[i];
+	}
 }

source/Filter.h

@@ -1,5 +1,6 @@
 #pragma once
 
+#include <array>
 #include <cmath>
 
 enum FilterModes
@@ -53,8 +54,14 @@ class StateVariableFilter
 	double low = 0.0;
 };
 
+class DualFilterBase
+{
+public:
+	void Process(double dt, double inL, double inR, double cutoff, double &outL, double &outR, bool highPass = false) {}
+};
+
 template<class T>
-class DualFilter
+class DualFilter : public DualFilterBase
 {
 public:
 	void Process(double dt, double inL, double inR, double cutoff, double &outL, double &outR, bool highPass = false)
@@ -68,23 +75,19 @@ class DualFilter
 	T right;
 };
 
-
 class MultiFilter
 {
 public:
 	void SetMode(FilterModes m) { mode = m; }
 	void Process(double dt, double &l, double &r, double cutoff, bool highPass = false);
 
 private:
-	void UpdateFilterMixes(double dt);
-
 	FilterModes mode = FilterModes::onePole;
-	DualFilter<OnePoleFilter> filter1;
-	DualFilter<TwoPoleFilter> filter2;
-	DualFilter<FourPoleFilter> filter4;
-	DualFilter<StateVariableFilter> filterSvf;
-	double filter1Mix = 0.0;
-	double filter2Mix = 0.0;
-	double filter4Mix = 0.0;
-	double filterSvfMix = 0.0;
+	std::array<DualFilterBase, numFilterModes> filters = {
+		DualFilter<OnePoleFilter>(),
+		DualFilter<TwoPoleFilter>(),
+		DualFilter<FourPoleFilter>(),
+		DualFilter<StateVariableFilter>()
+	};
+	std::array<double, numFilterModes> mix = {0.0, 0.0, 0.0, 0.0};
 };