dust3d/thirdparty/cgal/CGAL-5.1/include/CGAL/Arr_simple_point_location.h

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// Copyright (c) 2006,2007,2009,2010,2011 Tel-Aviv University (Israel).
// All rights reserved.
//
// This file is part of CGAL (www.cgal.org).
//
// $URL: https://github.com/CGAL/cgal/blob/v5.1/Arrangement_on_surface_2/include/CGAL/Arr_simple_point_location.h $
// $Id: Arr_simple_point_location.h 0779373 2020-03-26T13:31:46+01:00 Sébastien Loriot
// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
//
//
// Author(s) : Ron Wein <wein@post.tau.ac.il>
// (based on old version by Eyal Flato)
// Efi Fogel <efif@post.tau.ac.il>
#ifndef CGAL_ARR_SIMPLE_POINT_LOCATION_H
#define CGAL_ARR_SIMPLE_POINT_LOCATION_H
#include <CGAL/license/Arrangement_on_surface_2.h>
#include <CGAL/disable_warnings.h>
/*! \file
* Definition of the Arr_simple_point_location<Arrangement> template.
*/
#include <CGAL/Arr_point_location_result.h>
#include <CGAL/Arrangement_2/Arr_traits_adaptor_2.h>
#include <boost/optional.hpp>
namespace CGAL {
/*! \class
* A class that answers point-location and vertical ray-shooting queries
* on a 2D arrangement using a simple algorithm.
* The Arrangement parameter corresponds to an arrangement instantiation
* of type Arrangement_on_surface_2<GeomTraits, TopTraits>.
*/
template <typename Arrangement_>
class Arr_simple_point_location {
public:
typedef Arrangement_ Arrangement_2;
typedef typename Arrangement_2::Geometry_traits_2 Geometry_traits_2;
typedef typename Arrangement_2::Topology_traits Topology_traits;
typedef typename Arrangement_2::Vertex_const_handle Vertex_const_handle;
typedef typename Arrangement_2::Halfedge_const_handle Halfedge_const_handle;
typedef typename Arrangement_2::Face_const_handle Face_const_handle;
typedef typename Geometry_traits_2::Point_2 Point_2;
typedef typename Geometry_traits_2::X_monotone_curve_2 X_monotone_curve_2;
typedef Arr_point_location_result<Arrangement_2> Result;
typedef typename Result::Type Result_type;
// Support cpp11::result_of
typedef Result_type result_type;
protected:
#if CGAL_ARR_POINT_LOCATION_VERSION < 2
typedef Result_type Optional_result_type;
#else
typedef typename boost::optional<Result_type> Optional_result_type;
#endif
typedef typename Topology_traits::Dcel Dcel;
typedef Arr_traits_basic_adaptor_2<Geometry_traits_2> Traits_adaptor_2;
// Data members:
const Arrangement_2* m_arr; // The associated arrangement.
const Traits_adaptor_2* m_geom_traits; // Its associated geometry traits.
const Topology_traits* m_topol_traits; // Its associated topology traits.
#if CGAL_ARR_POINT_LOCATION_VERSION < 2
inline bool optional_empty(const CGAL::Object& obj) const { return obj.empty(); }
inline const Result_type& optional_assign(const CGAL::Object& t) const { return t; }
#else
inline bool optional_empty(const boost::optional<Result_type>& t) const { return (!t); }
inline const Result_type& optional_assign(const boost::optional<Result_type>& t) const { return *t; }
#endif
template<typename T>
Result_type make_result(T t) const { return Result::make_result(t); }
inline Optional_result_type make_optional_result() const { return Result::empty_optional_result(); }
inline Result_type default_result() const { return Result::default_result(); }
public:
/*! Default constructor. */
Arr_simple_point_location() :
m_arr(nullptr),
m_geom_traits(nullptr),
m_topol_traits(nullptr)
{}
/*! Constructor given an arrangement. */
Arr_simple_point_location(const Arrangement_2& arr) :
m_arr(&arr)
{
m_geom_traits =
static_cast<const Traits_adaptor_2*>(m_arr->geometry_traits());
m_topol_traits = m_arr->topology_traits();
}
/*! Attach an arrangement object. */
void attach(const Arrangement_2& arr)
{
m_arr = &arr;
m_geom_traits =
static_cast<const Traits_adaptor_2*>(m_arr->geometry_traits());
m_topol_traits = m_arr->topology_traits();
}
/*! Detach from the current arrangement object. */
void detach()
{
m_arr = nullptr;
m_geom_traits = nullptr;
m_topol_traits = nullptr;
}
/*!
* Locate the arrangement feature containing the given point.
* \param p The query point.
* \return An object representing the arrangement feature containing the
* query point. This object is either a Face_const_handle or a
* Halfedge_const_handle or a Vertex_const_handle.
*/
Result_type locate(const Point_2& p) const;
/*!
* Locate the arrangement feature which a upward vertical ray emanating from
* the given point hits.
* \param p The query point.
* \return An object representing the arrangement feature the ray hits.
* This object is either an empty object or a
* Halfedge_const_handle or a Vertex_const_handle.
*/
Result_type ray_shoot_up(const Point_2& p) const
{ return (_vertical_ray_shoot(p, true)); }
/*!
* Locate the arrangement feature which a downward vertical ray emanating
* from the given point hits.
* \param p The query point.
* \return An object representing the arrangement feature the ray hits.
* This object is either an empty object or a
* Halfedge_const_handle or a Vertex_const_handle.
*/
Result_type ray_shoot_down(const Point_2& p) const
{ return (_vertical_ray_shoot(p, false)); }
protected:
/*!
* Locate the arrangement feature which a vertical ray emanating from the
* given point hits (not inculding isolated vertices).
* \param p The query point.
* \param shoot_up Indicates whether the ray is directed upward or downward.
* \return An object representing the arrangement feature the ray hits.
* This object is either a Halfedge_const_handle,
* a Vertex_const_handle or an empty object.
*/
Optional_result_type _base_vertical_ray_shoot(const Point_2& p,
bool shoot_up) const;
/*!
* Locate the arrangement feature which a vertical ray emanating from the
* given point hits, considering isolated vertices.
* \param p The query point.
* \param shoot_up Indicates whether the ray is directed upward or downward.
* \return An object representing the arrangement feature the ray hits.
* This object is either a Halfedge_const_handle,
* a Vertex_const_handle or an empty object.
*/
Result_type _vertical_ray_shoot(const Point_2& p, bool shoot_up) const;
/*!
* Find the first halfedge with a given source vertex, when going clockwise
* from "6 o'clock" around this vertex.
* \param v The given vertex.
* \return The first halfedge.
*/
Halfedge_const_handle _first_around_vertex(Vertex_const_handle v) const;
};
} //namespace CGAL
// The member-function definitions can be found under:
#include <CGAL/Arr_point_location/Arr_simple_point_location_impl.h>
#include <CGAL/enable_warnings.h>
#endif