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#ifndef TRACKBALL_H
#define TRACKBALL_H

#include <QtGui>

#include "vector.h"

class TrackBall
{
public:
    enum TrackMode
    {
        Plane,
        Sphere,
    };
    TrackBall(TrackMode mode = Sphere);
    TrackBall(float angularVelocity, const gfx::Vector3f& axis, TrackMode mode = Sphere);
    // coordinates in [-1,1]x[-1,1]
    void push(const QPointF& p, const gfx::Quaternionf &transformation);
    void move(const QPointF& p, const gfx::Quaternionf &transformation);
    void release(const QPointF& p, const gfx::Quaternionf &transformation);
    void start(); // starts clock
    void stop(); // stops clock
    gfx::Quaternionf rotation() const;
private:
    gfx::Quaternionf m_rotation;
    gfx::Vector3f m_axis;
    float m_angularVelocity;

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

#endif