text: // Copyright (c) 2000  
  // Utrecht University (The Netherlands),
  // ETH Zurich (Switzerland),
  // INRIA Sophia-Antipolis (France),
  // Max-Planck-Institute Saarbruecken (Germany),
  // and Tel-Aviv University (Israel).  All rights reserved. 
  //
  // This file is part of CGAL (www.cgal.org); you can redistribute it and/or
  // modify it under the terms of the GNU Lesser General Public License as
  // published by the Free Software Foundation; either version 3 of the License,
  // or (at your option) any later version.
  //
  // Licensees holding a valid commercial license may use this file in
  // accordance with the commercial license agreement provided with the software.
  //
  // This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
  // WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  //
  // $URL: svn+ssh://scm.gforge.inria.fr/svn/cgal/branches/releases/CGAL-4.1-branch/Intersections_2/include/CGAL/Ray_2_Bbox_2_intersection.h $
  // $Id: Ray_2_Bbox_2_intersection.h 67093 2012-01-13 11:22:39Z lrineau $
  // 
  //
  // Author(s)     : Geert-Jan Giezeman
  
  
  #ifndef CGAL_RAY_2_BBOX_2_INTERSECTION_H
  #define CGAL_RAY_2_BBOX_2_INTERSECTION_H
  
  #include <CGAL/Bbox_2.h>
  #include <CGAL/Ray_2.h>
  #include <CGAL/kernel_assertions.h>
  #include <CGAL/number_utils.h>
  
  namespace CGAL {
  
  class Bbox_2_Ray_2_pair_impl;
  
  class CGAL_EXPORT Bbox_2_Ray_2_pair {
  public:
      enum Intersection_results {NO_INTERSECTION, POINT, SEGMENT};
      ~Bbox_2_Ray_2_pair() ;
      Bbox_2_Ray_2_pair() ;
      Bbox_2_Ray_2_pair(Bbox_2_Ray_2_pair const &o) ;
      Bbox_2_Ray_2_pair(Bbox_2 const &box,
                        double x, double y, double dx, double dy) ;
      Bbox_2_Ray_2_pair& operator=(Bbox_2_Ray_2_pair const &o) ;
      Intersection_results intersection_type() const;
      bool intersection(double &x, double &y) const;
      bool intersection(double &x1, double &y1, double &x2, double &y2) const;
  protected:
      Bbox_2_Ray_2_pair_impl *pimpl;
  };
  
  CGAL_EXPORT bool do_intersect_ray_2(
      const Bbox_2 &box, double x, double y, double dx, double dy);
  
  template <class Ray>
  bool do_intersect_ray_2(
      const Bbox_2 &box,
      const Ray &ray)
  {
      double startx = to_double(ray->start().x());
      double starty = to_double(ray->start().y());
      double dx = to_double(ray->direction().to_vector().x());
      double dy = to_double(ray->direction().to_vector().y());
      return do_intersect_ray_2(box, startx, starty, dx, dy);
  }
  
  template <class Ray>
  inline bool do_intersect_ray_2(
      const Ray &ray,
      const Bbox_2 &box)
  {
      return do_intersect_ray_2(box, ray);
  }
  } //namespace CGAL
  
  
  
  #endif
  