XML parser of OSG with Qt support

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#include <QDebug>
#include <QVBoxLayout>

#include <QAudioOutput>
#include <QAudioDeviceInfo>
#include <QtCore/qmath.h>
#include <QtCore/qendian.h>
#include "audiooutput.h"


const int DurationSeconds = 1;
const int ToneFrequencyHz = 600;
const int DataFrequencyHz = 44100;
const int BufferSize      = 32768;


WrapAudioStream::WrapAudioStream(osg::AudioStream *audioStream,
                     QObject *parent)
    :   QIODevice(parent)
    ,   _audioStream(audioStream)
{
}

WrapAudioStream::~WrapAudioStream()
{

}

void WrapAudioStream::start()
{
    open(QIODevice::ReadOnly);
}

void WrapAudioStream::stop()
{
    close();
}

qint64 WrapAudioStream::readData(char *data, qint64 len)
{
    qint64 total = 0;

    _audioStream->consumeAudioBuffer(data, len);

    total = len;

    return total;
}

qint64 WrapAudioStream::writeData(const char *data, qint64 len)
{
    Q_UNUSED(data);
    Q_UNUSED(len);

    return 0;
}

qint64 WrapAudioStream::bytesAvailable() const
{
//    return m_buffer.size() + QIODevice::bytesAvailable();
    return QIODevice::bytesAvailable();
}

AudioTest::AudioTest(osg::AudioStream *audioStream, QAudioFormat format)
    :   m_device(QAudioDeviceInfo::defaultOutputDevice())
    ,   m_generator(0)
    ,   m_audioOutput(0)
    ,   m_output(0)
    ,   m_buffer(BufferSize, 0)
    ,   _audioStream(audioStream)
    ,   m_format(format)
{
      initializeAudio();
}

void AudioTest::initializeAudio()
{

    m_pullMode = true;

    QAudioDeviceInfo info(QAudioDeviceInfo::defaultOutputDevice());
    if (!info.isFormatSupported(m_format)) {
        qWarning() << "Default format not supported - trying to use nearest";
        m_format = info.nearestFormat(m_format);
    }

    m_generator = new WrapAudioStream(_audioStream, this);

    createAudioOutput();
}

void AudioTest::createAudioOutput()
{
    delete m_audioOutput;
    m_audioOutput = 0;
    m_audioOutput = new QAudioOutput(m_device, m_format, this);
    connect(m_audioOutput, SIGNAL(notify()), SLOT(notified()));
    connect(m_audioOutput, SIGNAL(stateChanged(QAudio::State)), SLOT(stateChanged(QAudio::State)));
    m_generator->start();
    m_audioOutput->start(m_generator);
}

void AudioTest::pause()
{
    m_audioOutput->suspend();
}

void AudioTest::resume()
{
    m_audioOutput->resume();
}

AudioTest::~AudioTest()
{

}

void AudioTest::notified()
{
//    qWarning() << "bytesFree = " << m_audioOutput->bytesFree()
//               << ", " << "elapsedUSecs = " << m_audioOutput->elapsedUSecs()
//               << ", " << "processedUSecs = " << m_audioOutput->processedUSecs();
}

void AudioTest::stateChanged(QAudio::State state)
{
//    qWarning() << "state = " << state;
}