#ifndef __PNDDRCOPTMATVACUUM_H__
#define __PNDDRCOPTMATVACUUM_H__

/*! 
  \brief Class for optical material representation.

  This material class represents simply nothing (vacuum).
*/

class PndDrcOptMatVacuum : public PndDrcOptMatAbs
{

 private:
  /*! \brief Auxiliary function for assignment operator and copy constructor..
    \param s The object to copy.
  */
  void copy(const PndDrcOptMatVacuum& s);         

 public:

  //!                                             Empty constructor.
  PndDrcOptMatVacuum();                

  /*! Copy constructor.
    /param Object to copy.
  */ 
  PndDrcOptMatVacuum(const PndDrcOptMatVacuum& mat);

  /*! Assignment operator.
    /param Object to assign.
  */ 
  PndDrcOptMatVacuum& operator=(const PndDrcOptMatVacuum& mat);

  // Implementation of pure virtual functions from base class.
  PndDrcOptMatVacuum* clone() const;
  double refIndex(const double lambda) const;
  double refIndexDeriv(const double lambda) const;
  bool   absorptionFlag(double lambda, double length) const;  

 
};
#endif