// ============================================================================
//
// Copyright (c) 2000 The CGAL Consortium
//
// This software and related documentation is part of an INTERNAL release
// of the Computational Geometry Algorithms Library (CGAL). It is not
// intended for general use.
//
// ----------------------------------------------------------------------------
//
// release       : $CGAL_Revision $
// release_date  : $CGAL_Date $
//
// file          : include/CGAL/Partition_traits_2.h
// package       : $CGAL_Package: Partition_2 $
// maintainer    : Susan Hert <hert@mpi-sb.mpg.de>
// chapter       : Planar Polygon Partitioning
//
// revision      : $Revision$
// revision_date : $Date$
//
// author(s)     : Susan Hert <hert@mpi-sb.mpg.de>
//
// coordinator   : MPI (Susan Hert <hert@mpi-sb.mpg.de>)
//
// implementation: Traits class for polygon partitioning functions
// ============================================================================

#ifndef PARTITION_TRAITS_2_H
#define PARTITION_TRAITS_2_H

#include <CGAL/Polygon_2.h>
#include <CGAL/Polygon_traits_2.h>
#include <CGAL/Partition_traits_2_base.h>
#include <CGAL/polygon_function_objects.h>
#include <list>

namespace CGAL {

template <class R_>
class Partition_traits_2  : public Partition_traits_2_base<R_>
{
  public:
    typedef R_                                          R;
    typedef Partition_traits_2<R_>                      Self;
    typedef CGAL::Polygon_traits_2<R_>                  Poly_Traits;
    typedef typename Poly_Traits::Point_2               Point_2;
    typedef ::std::list<Point_2>                        Container;
    typedef CGAL::Polygon_2<Poly_Traits, Container>     Polygon_2;
    typedef typename R::Less_yx_2                       Less_yx_2;
    typedef typename R::Less_xy_2                       Less_xy_2;
    typedef typename R::Leftturn_2                      Leftturn_2;
    typedef typename R::Orientation_2                   Orientation_2;
    typedef typename R::Compare_y_2                     Compare_y_2;
    typedef typename R::Compare_x_2                     Compare_x_2;
    typedef Is_convex_2<Self>                           Is_convex_2;
    typedef Is_y_monotone_2<Self>                       Is_y_monotone_2;

    // needed by Indirect_edge_compare, used in y_monotone and greene_approx
    typedef typename R::Line_2                          Line_2;
    typedef typename R::Construct_line_2                Construct_line_2;
    typedef typename R::Compare_x_at_y_2                Compare_x_at_y_2;

    // needed by visibility graph and thus by optimal convex
    typedef Ray_2<R_>                                   Ray_2; 
    typedef typename R::Collinear_are_ordered_along_line_2
                                            Collinear_are_ordered_along_line_2;
    typedef typename R::Are_strictly_ordered_along_line_2
                                            Are_strictly_ordered_along_line_2;

    // needed by approx_convex (for constrained triangulation)
    // and optimal convex (for vis. graph)
    typedef typename R::Segment_2                       Segment_2;
    // needed by optimal convex (for vis. graph)
    typedef typename R::Construct_segment_2             Construct_segment_2;
    typedef typename R::Construct_ray_2                 Construct_ray_2;

 
    Construct_line_2
    construct_line_2_object() const
    {  return Construct_line_2(); }

    Compare_x_at_y_2
    compare_x_at_y_2_object() const
    { return Compare_x_at_y_2(); }

    Construct_segment_2
    construct_segment_2_object() const
    { return Construct_segment_2(); }

    Construct_ray_2
    construct_ray_2_object() const
    { return Construct_ray_2(); }

    Collinear_are_ordered_along_line_2
    collinear_are_ordered_along_line_2_object() const
    { return Collinear_are_ordered_along_line_2(); }

    Are_strictly_ordered_along_line_2
    are_strictly_ordered_along_line_2_object() const
    { return Are_strictly_ordered_along_line_2(); }

    Is_convex_2
    is_convex_2_object(const Self& traits) const
    {  return Is_convex_2(traits); }

    Is_y_monotone_2
    is_y_monotone_2_object(const Self& traits) const
    {  return Is_y_monotone_2(traits); }

    // necessary for convexity postcondition checking
    bool 
    lexicographically_xy_smaller(const Point_2& p, const Point_2& q) const
    {
       return Less_xy_2()(p,q);
    }
};

}

#endif // PARTITION_TRAITS_2_H