rotation.H

/*
 * This file is part of the "Archon" framework.
 * (http://files3d.sourceforge.net)
 *
 * Copyright © 2002 by Kristian Spangsege and Brian Kristiansen.
 *
 * Permission to use, copy, modify, and distribute this software and
 * its documentation under the terms of the GNU General Public License is
 * hereby granted. No representations are made about the suitability of
 * this software for any purpose. It is provided "as is" without express
 * or implied warranty. See the GNU General Public License
 * (http://www.gnu.org/copyleft/gpl.html) for more details.
 *
 * The characters in this file are ISO8859-1 encoded.
 *
 * The documentation in this file is in "Doxygen" style
 * (http://www.doxygen.org).
 */

#ifndef ARCHON_MATH_ROTATION_H
#define ARCHON_MATH_ROTATION_H

#include <archon/math/vector.H>

namespace Archon
{
  namespace Math
  {
    struct Rotation3
    {
      static const Rotation3 &zero()
      {
        static Rotation3 r = makeZero();
        return r;
      }

      Vector3 axis; // The 1-D sub space around which we are rotating
      double angle;

      Rotation3() {}
      Rotation3(const Vector3 &axis, double angle):
        axis(axis), angle(angle) {}

      Rotation3 operator-() const { return Rotation3(axis, -angle); }

      bool operator==(const Rotation3 &r) const
      {
        return axis == r.axis && angle == r.angle;
      }

      bool operator!=(const Rotation3 &r) const
      {
        return axis != r.axis || angle != r.angle;
      }

      void combineWith(const Rotation3 &);

    private:
      static Rotation3 makeZero()
      {
        return Rotation3(Vector3::zero(), 0);
      }
    };
  }
}

#endif // ARCHON_MATH_ROTATION_H

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