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50
51#ifndef TRACKBALL_H
52#define TRACKBALL_H
53
54#include <QQuaternion>
55#include <QTime>
56#include <QVector3D>
57
58class TrackBall
59{
60public:
61 enum TrackMode
62 {
63 Plane,
64 Sphere,
65 };
66 TrackBall(TrackMode mode = Sphere);
67 TrackBall(float angularVelocity, const QVector3D &axis, TrackMode mode = Sphere);
68 // coordinates in [-1,1]x[-1,1]
69 void push(const QPointF &p, const QQuaternion &transformation);
70 void move(const QPointF &p, const QQuaternion &transformation);
71 void release(const QPointF &p, const QQuaternion &transformation);
72 void start(); // starts clock
73 void stop(); // stops clock
74 QQuaternion rotation() const;
75private:
76 QQuaternion m_rotation;
77 QVector3D m_axis = QVector3D(0, 1, 0);
78 float m_angularVelocity = 0;
79
80 QPointF m_lastPos;
81 QTime m_lastTime = QTime::currentTime();
82 TrackMode m_mode;
83 bool m_paused = false;
84 bool m_pressed = false;
85};
86
87#endif
88

source code of qtbase/examples/widgets/graphicsview/boxes/trackball.h