eg-amp c++

gistfile1.cpp

#include "lv2.hpp"

#include <cmath> // for std::pow

// #define AMP_URI "http://lv2plug.in/plugins/eg-amp"

/** Define a macro for converting a gain in dB to a coefficient. */
#define DB_CO(g) ((g) > -90.0f ? std::pow(10.0f, (g) * 0.05f) : 0.0f)

class EG_Amp : public LV2_Plugin
{
public:
    EG_Amp(double sampleRate, const char* bundlePath)
        : LV2_Plugin(sampleRate, bundlePath) {}

protected:
    void connectPort(uint32_t port, void* dataLocation) override
    {
        buffers.connectPort(port, dataLocation);
    }

    void run(uint32_t sampleCount)
    {
        const float coef = DB_CO(*buffers.gain);

        for (uint32_t i = 0; i < sampleCount; ++i)
            buffers.output[i] = buffers.input[i] * coef;
    }

private:
    enum PortIndexes {
        kPortGain   = 0,
        kPortInput  = 1,
        kPortOutput = 2
    };

    struct PortBuffers {
        const float* gain;
        const float* input;
        float*       output;

        PortBuffers()
            : gain(nullptr),
              input(nullptr),
              output(nullptr) {}

        void connectPort(uint32_t port, void* dataLocation)
        {
            switch (port)
            {
            case kPortGain:
                gain = (const float*)dataLocation;
                break;
            case kPortInput:
                input = (const float*)dataLocation;
                break;
            case kPortOutput:
                output = (float*)dataLocation;
                break;
            }
        }
    };

    PortBuffers buffers;
};