Class DiffusionStep

reverb-example-code.h:116–155

template<int channels=8>
struct DiffusionStep {
	using Array = std::array<double, channels>;
	double delayMsRange = 50;
	
	std::array<int, channels> delaySamples;
	std::array<Delay, channels> delays;
	std::array<bool, channels> flipPolarity;
	
	void configure(double sampleRate) {
		double delaySamplesRange = delayMsRange*0.001*sampleRate;
		for (int c = 0; c < channels; ++c) {
			double rangeLow = delaySamplesRange*c/channels;
			double rangeHigh = delaySamplesRange*(c + 1)/channels;
			delaySamples[c] = randomInRange(rangeLow, rangeHigh);
			delays[c].resize(delaySamples[c] + 1);
			delays[c].reset();
			flipPolarity[c] = rand()%2;
		}
	}
	
	Array process(Array input) {
		// Delay
		Array delayed;
		for (int c = 0; c < channels; ++c) {
			delays[c].write(input[c]);
			delayed[c] = delays[c].read(delaySamples[c]);
		}
		
		// Mix with a Hadamard matrix
		Array mixed = delayed;
		Hadamard<double, channels>::inPlace(mixed.data());

		// Flip some polarities
		for (int c = 0; c < channels; ++c) {
			if (flipPolarity[c]) mixed[c] *= -1;
		}

		return mixed;
	}
};

template<int channels=8, int stepCount=4>
struct DiffuserEqualLengths {