// SpacePoint.h

#ifndef SpacePoint_H
#define SpacePoint_H

// Describes a space point. The default Space point is at the origin.
// Derived classes can be used to set values in cartesian, cylindrical
// or spherical coordinates.  Point is set in the constructor and
// cannot be changed.  The methods simply return different coordinates.
//
// Transformations (translations, rotations, etc) are carried out by
// external functions which return new SpacePoints.

#include <iostream>

#ifdef DEFECT_NO_BOOL
#include <bool.h>
#endif

class SpacePoint {

protected:  // data
  double _x;
  double _y;
  double _z;
  double _xy;
  double _xyz;
  double _phi;
  double _tht;

public:  // static methods

  // Return if two doubles are close enough to be considered equal.
  // This is used to compare components for operator==.
  static bool equal(double x1, double x2);

  // Return the tolerance used in equal.
  static double equal_tolerance();

public:  // methods

  // Default constructor.
  // Sets point to be the origin.
  SpacePoint( );

  // Destructor.
  virtual ~SpacePoint( );

  // Cartesian x.
  double x( ) const { return _x; };

  // Cartesian y.
  double y( ) const { return _y; };

  // Cartesian z.
  double z( ) const { return _z; };

  // Cylindrical r.
  double rxy( ) const { return _xy; };

  // Cylindrical phi.
  double phi( ) const { return _phi; };

  // Spherical r.
  double rxyz( ) const { return _xyz; };

  // Spherical theta.
  double theta( ) const { return _tht; };

  // cos(phi)
  double cos_phi( ) const;

  // sin(phi)
  double sin_phi( ) const;

  // cos(phi)
  double sin_theta( ) const;

  // cos(phi)
  double cos_theta( ) const;

};

std::ostream& operator<<(std::ostream & stream, const SpacePoint& spt);

//**********************************************************************

class CartesianPoint : public SpacePoint {

public:

  // Constructor.
  CartesianPoint(double x, double y, double z);

};
  
//**********************************************************************

class CylindricalPoint : public SpacePoint {

public:

  // Constructor.
  CylindricalPoint(double r, double phi, double z);

};
  
//**********************************************************************

class SphericalPoint : public SpacePoint {

public:

  // Constructor.
  SphericalPoint(double r, double phi, double theta);

};
  
//**********************************************************************
// Free functions.
//**********************************************************************

// Equality.

bool operator==(const SpacePoint& lhs, const SpacePoint& rhs);

//**********************************************************************

// Inequality.

bool operator!=(const SpacePoint& lhs, const SpacePoint& rhs);

//**********************************************************************

// Return the distance between two space points.
double distance(const SpacePoint spt1, const SpacePoint spt2);

//**********************************************************************

#endif