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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
// Qt-Security score:significant reason:default
#include "qmagnetometer.h"
#include "qmagnetometer_p.h"
QT_BEGIN_NAMESPACE
IMPLEMENT_READING(QMagnetometerReading)
/*!
\class QMagnetometerReading
\ingroup sensors_reading
\inmodule QtSensors
\since 5.1
\brief The QMagnetometerReading class represents one reading from the
magnetometer.
\section1 QMagnetometerReading Units
The magnetometer returns magnetic flux density values along 3 axes.
The scale of the values is teslas. The axes are arranged as follows.
\image sensors-coordinates2.jpg
{Device with positive and negative x, y, and z axes
extending in all six directions}
The magnetometer can report on either raw magnetic flux values or geomagnetic flux values.
By default it returns raw magnetic flux values. The QMagnetometer::returnGeoValues property
must be set to return geomagnetic flux values.
The primary difference between raw and geomagnetic values is that extra processing
is done to eliminate local magnetic interference from the geomagnetic values so they
represent only the effect of the Earth's magnetic field. This process is not perfect
and the accuracy of each reading may change.
The image below shows the difference between geomagnetic (on the left) and raw (on the right)
readings for a phone that is being subjected to magnetic interference.
\image sensors-geo-vs-raw-magnetism.jpg
{Diagram comparing geomagnetic readings, with the phone axes
aligned to the Magnetic North Pole, against raw readings skewed
by a nearby magnet}
The accuracy of each reading is measured as a number from 0 to 1.
A value of 1 is the highest level that the device can support and 0 is
the worst.
\section1 Calibration
If the device is reporting low accuracy, then calibration might be needed before acceptable measurements
can be provided.
Basic calibration can usually be done by either rotating your device in a figure of eight, or by
rotating the device along each of its three axes. For more information, check your device's
documentation on how to calibrate the magnetic sensor.
*/
/*!
\property QMagnetometerReading::x
\brief the raw magnetic flux density on the X axis.
Measured as teslas.
\sa {QMagnetometerReading Units}
*/
qreal QMagnetometerReading::x() const
{
return d->x;
}
/*!
Sets the raw magnetic flux density on the X axis to \a x.
*/
void QMagnetometerReading::setX(qreal x)
{
d->x = x;
}
/*!
\property QMagnetometerReading::y
\brief the raw magnetic flux density on the Y axis.
Measured as teslas.
\sa {QMagnetometerReading Units}
*/
qreal QMagnetometerReading::y() const
{
return d->y;
}
/*!
Sets the raw magnetic flux density on the Y axis to \a y.
*/
void QMagnetometerReading::setY(qreal y)
{
d->y = y;
}
/*!
\property QMagnetometerReading::z
\brief the raw magnetic flux density on the Z axis.
Measured as teslas.
\sa {QMagnetometerReading Units}
*/
qreal QMagnetometerReading::z() const
{
return d->z;
}
/*!
Sets the raw magnetic flux density on the Z axis to \a z.
*/
void QMagnetometerReading::setZ(qreal z)
{
d->z = z;
}
/*!
\property QMagnetometerReading::calibrationLevel
\brief the accuracy of the reading.
Measured as a value from 0 to 1 with higher values being better.
Note that this only changes when measuring geomagnetic flux density.
Raw magnetic flux readings will always have a value of 1.
\sa {QMagnetometerReading Units}, {Calibration}
*/
qreal QMagnetometerReading::calibrationLevel() const
{
return d->calibrationLevel;
}
/*!
Sets the accuracy of the reading to \a calibrationLevel.
*/
void QMagnetometerReading::setCalibrationLevel(qreal calibrationLevel)
{
d->calibrationLevel = calibrationLevel;
}
// =====================================================================
/*!
\class QMagnetometerFilter
\ingroup sensors_filter
\inmodule QtSensors
\since 5.1
\brief The QMagnetometerFilter class is a convenience wrapper around QSensorFilter.
The only difference is that the filter() method features a pointer to QMagnetometerReading
instead of QSensorReading.
*/
/*!
\fn QMagnetometerFilter::filter(QMagnetometerReading *reading)
Called when \a reading changes. Returns false to prevent the reading from propagating.
\sa QSensorFilter::filter()
*/
bool QMagnetometerFilter::filter(QSensorReading *reading)
{
return filter(static_cast<QMagnetometerReading*>(reading));
}
char const * const QMagnetometer::sensorType("QMagnetometer");
/*!
\class QMagnetometer
\ingroup sensors_type
\inmodule QtSensors
\since 5.1
\brief The QMagnetometer class is a convenience wrapper around QSensor.
The only behavioural difference is that this class sets the type properly.
This class also features a reading() function that returns a QMagnetometerReading instead of a QSensorReading.
For details about how the sensor works, see \l QMagnetometerReading.
\sa QMagnetometerReading
*/
/*!
Construct the sensor as a child of \a parent.
*/
QMagnetometer::QMagnetometer(QObject *parent)
: QSensor(QMagnetometer::sensorType, *new QMagnetometerPrivate, parent)
{
}
/*!
Destroy the sensor. Stops the sensor if it has not already been stopped.
*/
QMagnetometer::~QMagnetometer()
{
}
/*!
\fn QMagnetometer::reading() const
Returns the reading class for this sensor.
\sa QSensor::reading()
*/
QMagnetometerReading *QMagnetometer::reading() const
{
return static_cast<QMagnetometerReading*>(QSensor::reading());
}
/*!
\property QMagnetometer::returnGeoValues
\brief a value indicating if geomagnetic values should be returned.
Set to true to return geomagnetic flux density.
Set to false (the default) to return raw magnetic flux density.
The property must be set before calling start().
*/
bool QMagnetometer::returnGeoValues() const
{
Q_D(const QMagnetometer);
return d->returnGeoValues;
}
void QMagnetometer::setReturnGeoValues(bool returnGeoValues)
{
Q_D(QMagnetometer);
if (d->returnGeoValues != returnGeoValues) {
d->returnGeoValues = returnGeoValues;
emit returnGeoValuesChanged(returnGeoValues);
}
}
QT_END_NAMESPACE
#include "moc_qmagnetometer.cpp"