#ifndef REFERENCEPOINT_HH
#define REFERENCEPOINT_HH
//
// $Id: ReferencePoint.hpp,v 1.6 1998/10/23 14:32:53 hobbs Exp $
//
// File: ReferencePoint.hh
// Purpose: Define a geometry support element which is an arbirary reference
//    point.
// Created: 08-OCT-1997   John Hobbs
//
// $Revision: 1.6 $
//
//

// Include files
#include <geometry_system/components/GeometryElement.hpp>

namespace dgs {
class CartesianCoordinate;

/**  Define a geometry support element which is an arbirary reference point.

     Defines an arbitrary reference point, using Cartesian Coordinates.

  */
class ReferencePoint: public GeometryElement {
public:

  ///  Default constructor.
  ReferencePoint(): _cvers("$Revision: 1.6 $") {}

  /// The interface required by GeometryElement from which this is inherited.
  SpacePoint local_to_global(const CartesianCoordinate& lpt) const;

  /// The interface required by GeometryElement from which this is inherited.
  CartesianCoordinate global_to_local(const SpacePoint& gpt) const;

  /// Can't resize a reference point, but can attach kids.
  bool position_child_at(const CartesianCoordinate& lpt, GeometryElement& kid);
  
  /// Get source code version. Kept to allow following code changes
  const std::string& code_version() const { return _cvers; }

  ///  Stream insertion operator.
  friend std::ostream& operator<<(std::ostream& os, const ReferencePoint& me);

private:

  /// Help out positioning children.
  CartesianCoordinate xform_to_local(const GeometryXform& xf) const;

  /// Help out positioning children.
  GeometryXform local_to_xform(const CartesianCoordinate& lpt) const;

  /// RCS version
  std::string _cvers;  // Replaced at checkout

public:

  // Make me persistable.
  D0_OBJECT_SETUP(ReferencePoint);

};
}
#endif //REFERENCEPOINT_HH