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39#include <qmath.h>
40
41#include "qfreefallsensorgesturerecognizer.h"
42
43QT_BEGIN_NAMESPACE
44
45QFreefallSensorGestureRecognizer::QFreefallSensorGestureRecognizer(QObject *parent)
46 : QSensorGestureRecognizer(parent)
47 , active(0)
48 , detecting(0)
49{
50}
51
52QFreefallSensorGestureRecognizer::~QFreefallSensorGestureRecognizer()
53{
54}
55
56void QFreefallSensorGestureRecognizer::create()
57{
58}
59
60QString QFreefallSensorGestureRecognizer::id() const
61{
62 return QString("QtSensors.freefall");
63}
64
65bool QFreefallSensorGestureRecognizer::start()
66{
67 if (QtSensorGestureSensorHandler::instance()->startSensor(sensor: QtSensorGestureSensorHandler::Accel)) {
68 active = true;
69 connect(sender: QtSensorGestureSensorHandler::instance(),SIGNAL(accelReadingChanged(QAccelerometerReading*)),
70 receiver: this,SLOT(accelChanged(QAccelerometerReading*)));
71 } else {
72 active = false;
73 }
74 return active;
75
76}
77
78bool QFreefallSensorGestureRecognizer::stop()
79{
80 QtSensorGestureSensorHandler::instance()->stopSensor(sensor: QtSensorGestureSensorHandler::Accel);
81 disconnect(sender: QtSensorGestureSensorHandler::instance(),SIGNAL(accelReadingChanged(QAccelerometerReading*)),
82 receiver: this,SLOT(accelChanged(QAccelerometerReading*)));
83 active = false;
84
85 return active;
86}
87
88bool QFreefallSensorGestureRecognizer::isActive()
89{
90 return active;
91}
92
93#define FREEFALL_THRESHOLD 1.0
94#define LANDED_THRESHOLD 20.0
95#define FREEFALL_MAX 4
96
97void QFreefallSensorGestureRecognizer::accelChanged(QAccelerometerReading *reading)
98{
99 const qreal x = reading->x();
100 const qreal y = reading->y();
101 const qreal z = reading->z();
102 qreal sum = qSqrt(v: x * x + y * y + z * z);
103
104 if (qAbs(t: sum) < FREEFALL_THRESHOLD) {
105 detecting = true;
106 freefallList.append(t: sum);
107 } else {
108 if (detecting && qAbs(t: sum) > LANDED_THRESHOLD) {
109 Q_EMIT landed();
110 Q_EMIT detected("landed");
111 freefallList.clear();
112 }
113 }
114
115 if (freefallList.count() > FREEFALL_MAX) {
116 Q_EMIT freefall();
117 Q_EMIT detected("freefall");
118 }
119}
120
121
122QT_END_NAMESPACE
123
124

source code of qtsensors/src/plugins/sensorgestures/qtsensors/qfreefallsensorgesturerecognizer.cpp