Quat.h

/****************************************************************************
 * Copyright 2005 Evan Drumwright
 * This library is distributed under the terms of the GNU General Public 
 * License (found in COPYING).
 ****************************************************************************/

#ifndef _QUAT_H
#define _QUAT_H

#include <Physsim/Base.h>
#include <Physsim/VectorN.h>
#include <Physsim/Vector3.h>

namespace Physsim {

class Matrix3;
class Matrix4;
class AAngle;


class Quat : public Base
{
        public:
                Quat();
                Quat(Real x, Real y, Real z, Real w);
                Quat(boost::shared_array<const Real>  q);
                Quat(const Quat& q);
                Quat(const VectorN& v);
                Quat(const Matrix3* m);
                Quat(const Matrix4* m);
                Quat(const AAngle* a);
                static Quat zero();
                void conjugate();
                static Quat conjugate(const Quat& q);
                bool epsilon_equals(const Quat& q, Real epsilon);
                static bool epsilon_equals(const Quat& q1, const Quat& q2, Real epsilon);
                void slerp(const Quat& q, Real alpha);
                static Quat slerp(const Quat& q1, const Quat& q2, Real alpha);
                void inverse();
                static Quat inverse(const Quat& q);
                void normalize();
                static Quat normalize(const Quat& q); 
                void set(const VectorN& v);
                void set(const AAngle* a);
                void set(const Matrix3* m);
                void set(const Matrix4* m);
                Quat operator-(const Quat& q) const;
                void operator-=(const Quat& q);
                Quat operator+(const Quat& q) const;
                void operator+=(const Quat& q);
                void operator=(const Quat& q);
                Quat operator*(const Quat& q) const;
                Quat operator*(Real scalar) const;
                void operator*=(const Quat& q);
                void operator*=(Real scalar);
                Real magnitude() const;
                static Quat deriv(const Quat& q, const Vector3& w);
                static Vector3 to_omega(const Quat& q, const Quat& qd);
                
                Real _x;

                Real _y;

                Real _z; 

                Real _w;
};

Quat operator*(Real scalar, const Quat& q);
std::ostream& operator<<(std::ostream& out, const Quat& q);

}
#endif

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