#ifndef __GEOMETRY_H
#define __GEOMETRY_H


// System Headers
#include <iostream>
#include <strstream>
using namespace std;


class Geometry
{
 private:
  //double ;
    
 public:
  //! Constructor of the class.
  Geometry ( );
  //! Destructor of the class.
  ~Geometry ( );
  
  //Methods
  
  //Distance between 2 points
  double DistPP(double A[3], double B[3]);

  //Finds direction of a track from A to B
  void FindDir(double& theta,double& phi,double A[3], double B[3]);

  //Modulus of a Vector
  double Mod(double vec[3]);

  //Normalizes a vector
  void Norm(double versor[3], double vector[3]);

  //Converts zenith & azimuth to a normalized vector
  void Dir2Vec(double versor[3],double& thetad, double& phid);

  //Addiction of vectors
  void AddVec(double sum[3],double vec1[3], double vec2[3]);

  //Multiplication by scalar
  void MultScal(double prod[3], double vec1[3], double factor);

  //Scalar Product
  double ScalProd(double vec1[3], double vec2[3]);

  //Angle between two vectors
  double Angle2Vec(double vec1[3], double vec2[3]);

  //Vector Product
  double VecProd(double prod[3],double vec1[3], double vec2[3]);

  //Defines a track
  void Track(double track[6],double A[3], double vec[3]);

  //Intersection of tracks
  void IntTrack(double A[3], double tr1[6], double tr2[6]);

  //Distance of a point to a track
  double DistPT(double P[3], double track[6]);

  //Find plane (from 3 points)
  void Plane(double plane[9], double A[3],double B[3], double C[3]);

  //Intersection of Track and Plane
  void IntTrPl(double A[3], double track[6], double plane[9]);

  //Definition of a Sphere
  void Sphere(double sphere[4],double O[3], double& radius);

  //Intersection of Track and Sphere
  void IntTrSph(double track[6],double sphere[4]);

};

#endif // __GEOMETRY