chromaflock/Source/DSP/Delay.h

#pragma once
#include <vector>
#include <algorithm>
#include <cmath>

class Delay {
public:
    void prepare(double sr) {
        sampleRate = sr;
        int maxSamples = static_cast<int>(sr * 2.0);
        bufferL.resize(maxSamples, 0.0f);
        bufferR.resize(maxSamples, 0.0f);
        writePos = 0;
    }

    void setParameters(float timeMs, float fb, float mx) {
        timeSamples = static_cast<int>(timeMs * 0.001f * sampleRate);
        int bufMax = static_cast<int>(bufferL.size()) - 1;
        timeSamples = std::clamp(timeSamples, 1, bufMax);
        feedback = std::clamp(fb, 0.0f, 0.95f);
        mix = std::clamp(mx, 0.0f, 1.0f);
    }

    void process(float& left, float& right) {
        int bufSize = static_cast<int>(bufferL.size());

        int readPos = (writePos - timeSamples + bufSize) % bufSize;

        float outL = bufferL[readPos];
        float outR = bufferR[readPos];

        bufferL[writePos] = left + outL * feedback;
        bufferR[writePos] = right + outR * feedback;

        writePos = (writePos + 1) % bufSize;

        left = left * (1.0f - mix) + outL * mix;
        right = right * (1.0f - mix) + outR * mix;
    }

private:
    std::vector<float> bufferL, bufferR;
    int writePos = 0;
    double sampleRate = 44100;
    int timeSamples = 8820;
    float feedback = 0.3f;
    float mix = 0.25f;
};