Modulator.h

#ifndef MODULATOR_HPP__
#define MODULATOR_HPP__
 
#include "JS8_Audio/AudioDevice.h"
 
#include <QAudio>
#include <QPointer>
 
class SoundOutput;

class Modulator final : public AudioDevice {
    Q_OBJECT;
 
  public:
    enum class State { Synchronizing, Active, Idle };
 
    // Constructor
 
    explicit Modulator(QObject *parent = nullptr) : AudioDevice{parent} {}
 
    // Inline accessors

    bool isIdle() const { return m_state.load() == State::Idle; }
 
    // Manipulators
 
    void close() override;

    Q_SLOT void setAudioFrequency(double const audioFrequency) {
        m_audioFrequency = audioFrequency;
    }
 
    // Slots
 
    Q_SLOT void start(double audioFrequency, int submode, double tx_delay,
                      SoundOutput *stream, Channel channel);
    Q_SLOT void stop(bool quick = false);
    Q_SLOT void tune(bool state = true);
 
  protected:
    // QIODevice protocol
 
    qint64 readData(char *, qint64) override;
    qint64 writeData(char const *, qint64) override {
        return -1; // we don't consume data
    }
 
    // In current Qt versions, bytesAvailable() must return a size
    // that exceeds some threshold in order for the AudioSink to go
    // into Active state and start pulling data. This behavior began
    // on Windows with the 6.4 release, on Mac with 6.8, and on Linux
    // with 6.9.
    //
    // See: https://bugreports.qt.io/browse/QTBUG-108672
 
    qint64 bytesAvailable() const override { return 8000; }
 
  private:
    // Data members
 
    QPointer<SoundOutput> m_stream;
    std::atomic<State> m_state = State::Idle;
    bool m_quickClose = false;
    bool m_tuning = false;
    double m_audioFrequency;
    double m_audioFrequency0;
    double m_toneSpacing;
    double m_phi;
    double m_dphi;
    double m_amp;
    double m_nsps;
    qint64 m_silentFrames;
    unsigned m_ic;
    unsigned m_isym0;
};
 
#endif