- Qt 5.5
- Qt Widgets
- Boxes
- trackball.h Example File
- Qt 5.5.1 Reference Documentation

# trackball.h Example File

graphicsview/boxes/trackball.h

    /****************************************************************************
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    ** Copyright (C) 2015 The Qt Company Ltd.
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    ** This file is part of the demonstration applications of the Qt Toolkit.
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    ** $QT_BEGIN_LICENSE:LGPL21$
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    #ifndef TRACKBALL_H
    #define TRACKBALL_H

    #include <QtWidgets>

    #include <QtGui/qvector3d.h>
    #include <QtGui/qquaternion.h>

    class TrackBall
    {
    public:
        enum TrackMode
        {
            Plane,
            Sphere,
        };
        TrackBall(TrackMode mode = Sphere);
        TrackBall(float angularVelocity, const QVector3D& axis, TrackMode mode = Sphere);
        // coordinates in [-1,1]x[-1,1]
        void push(const QPointF& p, const QQuaternion &transformation);
        void move(const QPointF& p, const QQuaternion &transformation);
        void release(const QPointF& p, const QQuaternion &transformation);
        void start(); // starts clock
        void stop(); // stops clock
        QQuaternion rotation() const;
    private:
        QQuaternion m_rotation;
        QVector3D m_axis;
        float m_angularVelocity;

        QPointF m_lastPos;
        QTime m_lastTime;
        bool m_paused;
        bool m_pressed;
        TrackMode m_mode;
    };

    #endif