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36
37#ifndef QQUICKVELOCITYCALCULATOR_P_P_H
38#define QQUICKVELOCITYCALCULATOR_P_P_H
39
40//
41// W A R N I N G
42// -------------
43//
44// This file is not part of the Qt API. It exists purely as an
45// implementation detail. This header file may change from version to
46// version without notice, or even be removed.
47//
48// We mean it.
49//
50
51#include <QtCore/qpoint.h>
52#include <QtCore/qelapsedtimer.h>
53
54QT_BEGIN_NAMESPACE
55
56class QQuickVelocityCalculator
57{
58public:
59 void startMeasuring(const QPointF &point1, qint64 timestamp = 0);
60 void stopMeasuring(const QPointF &m_point2, qint64 timestamp = 0);
61 void reset();
62 QPointF velocity() const;
63
64private:
65 QPointF m_point1;
66 QPointF m_point2;
67 qint64 m_point1Timestamp = 0;
68 qint64 m_point2Timestamp = 0;
69 // When a timestamp isn't available, we must use a timer.
70 // When stopMeasuring() has been called, we store the elapsed time in point2timestamp.
71 QElapsedTimer m_timer;
72};
73
74QT_END_NAMESPACE
75
76#endif // QQUICKVELOCITYCALCULATOR_P_P_H
77

source code of qtquickcontrols2/src/quicktemplates2/qquickvelocitycalculator_p_p.h