main.cpp

#include <cmath>
#include <matplot/matplot.h>

#include "chowdsp_wdf/chowdsp_wdf.h"

using namespace chowdsp::wdft;

class vca_1
{
public:
    vca_1() = default;
    float _vcc = 0.0;

    void prepare (double sampleRate)
    {
        C1.prepare ((float) sampleRate);
    }

    void reset()
    {
        C1.reset();
    }

    void setCircuitParams ()
    {
    }

    void setCircuitElements (float vcc, float vinRes, float vccRes)
    {   
        _vcc = vcc;
        Vcc.setVoltage(vcc);
        Vin.setVoltage (0.0);
        Vin.setResistanceValue(vinRes);
        Vcc.setResistanceValue(vccRes);
    }

    inline float processSample (float x)
    {
        Vcc.setVoltage(_vcc);
        Vin.setVoltage (x);

        d1.incident (P1.reflected());
        P1.incident (d1.reflected());

        return current<float> (d1);
    }

    ResistiveVoltageSourceT<float> Vcc;
    ResistiveVoltageSourceT<float> Vin;
    CapacitorT<float> C1 { 22.0e-9f };

    WDFSeriesT<float, decltype (Vin), decltype (C1)> S1 { Vin, C1 };
    PolarityInverterT<float, decltype (S1)> inv {S1};
    WDFParallelT<float, decltype (Vcc), decltype (inv)> P1 { Vcc, inv };
    PolarityInverterT<float, decltype (P1)> inv2 {P1};
    // DiodeT<float, decltype (inv2)> d1 { inv2, 0.0115e-9f };
    DiodeT<float, decltype (inv2)> d1 { inv2, 2.52e-9f };
}; // vca_1

class vca_2
{
public:
    vca_2() = default;

    void prepare (double sampleRate)
    {
        C1.prepare ((float) sampleRate);
    }

    void reset()
    {
        C1.reset();
    }

    void setCircuitParams ()
    {
    }

    void setCircuitElements (float iinRes, float venvRes)
    {   
        Iin.setResistanceValue(iinRes);
        Venv.setResistanceValue(venvRes);
    }

    inline float processSample (float iin, float venv)
    {
        Iin.setCurrent (iin);
        Venv.setVoltage(venv);

        d1.incident (S1.reflected());
        S1.incident (d1.reflected());

        return voltage<float> (invS1) + voltage<float> (C1);
    }

    ResistiveVoltageSourceT<float> Venv;
    ResistiveCurrentSourceT<float> Iin;
    CapacitorT<float> C1 { 2.7e-9f };

    WDFParallelT<float, decltype (C1), decltype (Iin)> P1 { C1, Iin };
    PolarityInverterT<float, decltype (C1)> invC1 {C1};
    WDFSeriesT<float, decltype (Venv), decltype (P1)> S1 { Venv, P1 };
    PolarityInverterT<float, decltype (S1)> invS1 {S1};
    DiodeT<float, decltype (invS1)> d1 { invS1, 2.52e-9f };
}; // vca_2

using namespace matplot;

std::vector<float> venv;
std::vector<float> in;
std::vector<float> in2;
std::vector<float> in3;
std::vector<float> in4;
std::vector<float> out;
std::vector<float> out2;
std::vector<float> out3;

vca_1 vca1;
vca_2 vca2;

int main() {

    float m_time = 0.0;
    float m_amplitude = 0.23;
    float m_frequency = 440.0;
    float sr = 48000.0;
    float oneOverSr = 1/sr;
    float venvStep = 2.089e-3;
    float venvStart = 6.0;

    venv.resize(1024);
    for (int i = 0; i < 1024; ++i) {
        venv[i] = venvStart - i * venvStep;
    }

    vca1.prepare(sr);
    vca2.prepare(sr);
    //                      Vcc   Vinres    Vccres
    vca1.setCircuitElements(12.0, 100.0, 2200000.0);
    //                      Iinres    Venvres
    vca2.setCircuitElements(20.0e6, 15.0e3);

    in.resize(1024);
    in2.resize(1024);
    in3.resize(1024);
    in4.resize(1024);
    out.resize(1024);
    out2.resize(1024);
    out3.resize(1024);

    for (int i = 0; i < 1024; ++i)
    {
        float value = m_amplitude * sin(2 * M_PI * m_frequency * m_time);
        in[i] = value;

        m_time += oneOverSr;

        vca1.processSample(in[i]);
        out[i] = (current<float> (vca1.d1) * 1e-12) * 1.6727;

        vca2.processSample(out[i], venv[i]);
        out2[i] = voltage<float> (vca2.C1) * -1.0 + voltage<float> (vca2.d1);

        out3[i] = voltage<float> (vca1.d1);
    }

    for (int i = 0; i < 1024; ++i) {
    }

    // plot(in);
    // plt::plot(in2, "red");
    // plt::plot(in3, "green");
    // hold(on);
    // plot(out)->use_y2(true);
    // plot(out3);

    // plot(out);
    plot(out2);
    // plot(venv, "red");
    show();
}

// int main() {

//     auto x = linspace(0, 10);
//     auto y1 = transform(x, [](double x) { return sin(3 * x); });
//     plot(x, y1);

//     hold(on);
//     auto z = transform(x, [](double x) { return sin(3 * x) * exp(0.5 * x); });
//     plot(x, z)->use_y2(true);
//     y2lim({-150, 150});

//     show();
//     return 0;
// }

Makefile

# Untar this in current dir
# https://github.com/alandefreitas/matplotplusplus/releases/download/v1.1.0/matplotplusplus-1.1.0-Linux.tar.gz

LDFLAGS = lib/libmatplot.a lib/Matplot++/libnodesoup.a -lpng -lz -ltiff -ljpeg
CXXFLAGS = -std=c++17 -I../chowdsp_wdf/include  -Iinclude

SRC = main.cpp
OUT = main

$(OUT): $(SRC)
	$(CXX) $(CXXFLAGS) -o $(SRC).o -c $(SRC)
	$(CXX) $(SRC).o $(LDFLAGS) -o $(OUT)

run: $(OUT)
	./$(OUT)

clean:
	rm $(OUT)