#ifndef __JEULERMATRIX3D__
#define __JEULERMATRIX3D__

#include <cmath>

#include "JGeometry3D/JRotation3D.hh"
#include "JGeometry3D/JEulerAngle3D.hh"


namespace JGEOMETRY3D {


  /**
   * Euler matrix
   *
   * The Euler matrix is a genuine 3D rotation matrix, i.e.
   * the inverse of an Euler mtarix is equal to its tranpose.
   *
   * The Euler angles are defined as follows:
   *
   *    1/ alpha      2D rotation around Z  -axis;
   *    2/ beta       2D rotation around X' -axis;
   *    3/ gamma      2D rotation around Z''-axis;
   */
  class JEulerMatrix3D :
    public JRotation3D
  {
  public:
    /**
     * Default constructor (= identity matrix).
     */
    JEulerMatrix3D() :
      JRotation3D()
    {}


    /**
     * Constructor.
     *
     * \param  euler  Euler angles
     */
    JEulerMatrix3D(const JEulerAngle3D& euler) :
      JRotation3D()
    {
      const double ca = cos(euler.getAlpha());
      const double sa = sin(euler.getAlpha());
      const double cb = cos(euler.getBeta());
      const double sb = sin(euler.getBeta());
      const double cg = cos(euler.getGamma());
      const double sg = sin(euler.getGamma());

      a00_ =  cg*ca - sg*cb*sa;  a01_ = -cg*sa - sg*cb*ca;  a02_ =  sg*sb;
      a10_ =  sg*ca + cg*cb*sa;  a11_ = -sg*sa + cg*cb*ca;  a12_ = -cg*sb;
      a20_ =  sb*sa;             a21_ =  sb*ca;             a22_ =  cb;
    }
  };
}

#endif