QGyroscope readingChanged interval changes if QRotationSensor is used

[rentner323]

Hi,
I found a very strange behaviour.
The interval at which the readings will change (updated) depends on the types of sensor I use in my application!
Take a look at the following Code snipped:

SensorModuleV3::SensorModuleV3(QObject *parent) : QThread(parent)
{
    pAccelerometer = new QAccelerometer(this);
    pGyroscope = new QGyroscope(this);
    pRotationSensor = new QRotationSensor(this);

    pAccelerometer->stop();
    pGyroscope->stop();
    pRotationSensor->stop();

    pAccelerometer->setAlwaysOn(true);
    pAccelerometer->setActive(true);
    pAccelerometer->setAxesOrientationMode(QSensor::FixedOrientation);
    pAccelerometer->setSkipDuplicates(false);
    pAccelerometer->setAccelerationMode(QAccelerometer::Combined);

    pGyroscope->setAlwaysOn(true);
    pGyroscope->setActive(true);
    pGyroscope->setAxesOrientationMode(QSensor::FixedOrientation);
    pGyroscope->setSkipDuplicates(false);

    pAccelerometer->start();
    pGyroscope->start();
    //pRotationSensor->start(); // Uncomment and gyroscope interval will change!
}

SensorModuleV3::~SensorModuleV3()
{
    pAccelerometer->stop();
    pGyroscope->stop();

    delete pAccelerometer;
    delete pGyroscope;
    delete pRotationSensor;
}

void SensorModuleV3::slotTest()
{
    qint64 timestampEnd = QDateTime::currentMSecsSinceEpoch() + 1000;
    quint64 lastGyroPreciseTimestamp;
    quint64 lastAccelerometerPreciseTimestamp;
    while (QDateTime::currentMSecsSinceEpoch() < timestampEnd) {
        quint64 currentGyroPreciseTimestamp = pGyroscope->reading()->timestamp();
        quint64 gyroTimeDiff = currentGyroPreciseTimestamp - lastGyroPreciseTimestamp;
        if (gyroTimeDiff > 0) {
            qDebug() << "gyro precise diff:" << gyroTimeDiff;
            lastGyroPreciseTimestamp = currentGyroPreciseTimestamp;
        }

        quint64 currentAccelerometerPreciseTimestamp = pAccelerometer->reading()->timestamp();
        quint64 accelTimeDiff = currentAccelerometerPreciseTimestamp - lastAccelerometerPreciseTimestamp;
        if (accelTimeDiff > 0) {
            qDebug() << "accel precise diff:" << accelTimeDiff;
            lastAccelerometerPreciseTimestamp = currentAccelerometerPreciseTimestamp;
        }
    }
}

On my device (Samsung S4 mini) I get values around about 22 ms for "accelTimeDiff" and "gyroTimeDiff". If I uncomment the line "pRotationSensor->start();" the value for "gyroTimeDiff" will change to around about 6 ms!

Can someone try to reproduce this on another device?
Can someone tell me why this is happening?