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cgal/Arrangement_on_surface_2/include/CGAL/Arr_accessor.h

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// Copyright (c) 2005 Tel-Aviv University (Israel).
// All rights reserved.
//
// This file is part of CGAL (www.cgal.org); you may redistribute it under
// the terms of the Q Public License version 1.0.
// See the file LICENSE.QPL distributed with CGAL.
//
// 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.
//
// $URL$
// $Id$
//
//
// Author(s) : Ron Wein <wein@post.tau.ac.il>
// Efi Fogel <efif@post.tau.ac.il>
#ifndef CGAL_ARR_ACCESSOR_H
#define CGAL_ARR_ACCESSOR_H
/*! \file
* Definition of the Arr_accessor<Arrangement> class.
*/
#include <CGAL/Arrangement_2/Arr_traits_adaptor_2.h>
CGAL_BEGIN_NAMESPACE
/*! \class
* A class that provides access to some of the internal arrangement operations.
* Used mostly by the global insertion functions and by the sweep-line visitors
* for utilizing topological and geometrical information available during the
* algorithms they perform.
* The Arrangement parameter corresponds to an arrangement instantiation
* (of the template Arrangement_on_surface_2).
*/
template <class Arrangement_>
class Arr_accessor
{
public:
typedef Arrangement_ Arrangement_2;
typedef Arr_accessor<Arrangement_2> Self;
typedef typename Arrangement_2::Size Size;
typedef typename Arrangement_2::Point_2 Point_2;
typedef typename Arrangement_2::X_monotone_curve_2 X_monotone_curve_2;
typedef typename Arrangement_2::Vertex_handle Vertex_handle;
typedef typename Arrangement_2::Vertex_const_handle Vertex_const_handle;
typedef typename Arrangement_2::Halfedge_handle Halfedge_handle;
typedef typename Arrangement_2::Halfedge_const_handle Halfedge_const_handle;
typedef typename Arrangement_2::Face_handle Face_handle;
typedef typename Arrangement_2::Face_const_handle Face_const_handle;
typedef typename Arrangement_2::Ccb_halfedge_circulator
Ccb_halfedge_circulator;
private:
typedef typename Arrangement_2::DVertex DVertex;
typedef typename Arrangement_2::DHalfedge DHalfedge;
typedef typename Arrangement_2::DFace DFace;
typedef typename Arrangement_2::DOuter_ccb DOuter_ccb;
typedef typename Arrangement_2::DInner_ccb DInner_ccb;
typedef typename Arrangement_2::DIso_vertex DIso_vertex;
private:
Arrangement_2 *p_arr; // The associated arrangement.
public:
/*! Constructor with an associated arrangement. */
Arr_accessor (Arrangement_2& arr) :
p_arr (&arr)
{}
/* Get the arrangement. */
Arrangement_2& arrangement ()
{
return (*p_arr);
}
/* Get the arrangement (const version). */
const Arrangement_2& arrangement() const
{
return (*p_arr);
}
/// \name Accessing the notification functions (for the global functions).
//@{
/*! Notify that a global operation is about to take place. */
void notify_before_global_change ()
{
p_arr->_notify_before_global_change();
}
/*! Notify that a global operation was completed. */
void notify_after_global_change ()
{
p_arr->_notify_after_global_change();
}
//@}
/// \name Local operations and predicates for the arrangement.
//@{
/*!
* Locate the arrangement feature that contains the given curve-end.
* \param cv The curve.
* \param ind ARR_MIN_END if we refer to cv's minimal end;
* ARR_MAX_END if we refer to its maximal end.
* \param ps_x The boundary condition in x.
* \param ps_y The boundary condition in y.
* \pre The relevant end of cv has boundary conditions in x or in y.
* \return An object that contains the curve end.
* This object may wrap a Face_const_handle (the general case),
* or a Halfedge_const_handle (in case of an overlap).
*/
CGAL::Object locate_curve_end (const X_monotone_curve_2& cv,
Arr_curve_end ind,
Arr_parameter_space ps_x,
Arr_parameter_space ps_y) const
{
CGAL_precondition (ps_x != ARR_INTERIOR || ps_y != ARR_INTERIOR);
// Use the topology traits to locate the unbounded curve end.
CGAL::Object obj =
p_arr->topology_traits()->locate_curve_end (cv, ind,
ps_x, ps_y);
// Return a handle to the DCEL feature.
DFace *f;
if (CGAL::assign (f, obj))
return (CGAL::make_object (p_arr->_const_handle_for (f)));
DHalfedge *he;
if (CGAL::assign (he, obj))
return (CGAL::make_object (p_arr->_const_handle_for (he)));
DVertex *v;
if (CGAL::assign (v, obj))
return (CGAL::make_object (p_arr->_const_handle_for (v)));
// We should never reach here:
CGAL_error();
return Object();
}
/*!
* Locate the place for the given curve around the given vertex.
* \param vh A handle for the arrangement vertex.
* \param cv The given x-monotone curve.
* \pre v is one of cv's endpoints.
* \return A handle for a halfedge whose target is v, where cv should be
* inserted between this halfedge and the next halfedge around this
* vertex (in a clockwise order).
*/
Halfedge_handle locate_around_vertex (Vertex_handle vh,
const X_monotone_curve_2& cv) const
{
typedef
Arr_traits_basic_adaptor_2<typename Arrangement_2::Geometry_traits_2>
Traits_adaptor_2;
const Traits_adaptor_2 *m_traits =
static_cast<Traits_adaptor_2*> (p_arr->geometry_traits());
Arr_curve_end ind = ARR_MIN_END;
if (m_traits->is_bounded_2_object() (cv, ARR_MAX_END) &&
m_traits->equal_2_object() (vh->point(),
m_traits->construct_max_vertex_2_object()(cv)))
{
ind = ARR_MAX_END;
}
DHalfedge * he = p_arr->_locate_around_vertex(p_arr->_vertex (vh), cv, ind);
CGAL_assertion (he != NULL);
return (p_arr->_handle_for (he));
}
/*!
* Locate the place for the given curve-end around the given vertex,
* which lies on the boundary.
* \param vh A handle for the arrangement vertex.
* \param cv The curve.
* \param ind ARR_MIN_END if we refer to cv's minimal end;
* ARR_MAX_END if we refer to its maximal end.
* \param ps_x The boundary condition in x.
* \param ps_y The boundary condition in y.
* \pre The relevant end of cv has boundary conditions in x or in y.
* \return A handle for a halfedge whose target is v, where cv should be
* inserted between this halfedge and the next halfedge around this
* vertex (in a clockwise order).
*/
Halfedge_handle
locate_around_boundary_vertex (Vertex_handle vh,
const X_monotone_curve_2& cv,
Arr_curve_end ind,
Arr_parameter_space ps_x,
Arr_parameter_space ps_y) const
{
CGAL_precondition (ps_x != ARR_INTERIOR || ps_y != ARR_INTERIOR);
// Use the topology traits to locate the unbounded curve end.
DHalfedge* he = p_arr->topology_traits()->
locate_around_boundary_vertex (p_arr->_vertex (vh),
cv, ind, ps_x, ps_y);
CGAL_assertion (he != NULL);
return (p_arr->_handle_for (he));
}
/*!
* Compute the distance (in halfedges) between two halfedges.
* \param e1 A handle for the source halfedge.
* \param e2 A handle for the destination halfedge.
* \return In case e1 and e2 belong to the same connected component, the
* function returns number of boundary halfedges between the two
* halfedges. Otherwise, it returns (-1).
*/
int halfedge_distance (Halfedge_const_handle e1,
Halfedge_const_handle e2) const
{
// If the two halfedges do not belong to the same component, return (-1).
const DHalfedge *he1 = p_arr->_halfedge (e1);
const DHalfedge *he2 = p_arr->_halfedge (e2);
if (he1 == he2)
return (0);
const DInner_ccb *ic1 = (he1->is_on_inner_ccb()) ? he1->inner_ccb() : NULL;
const DOuter_ccb *oc1 = (ic1 == NULL) ? he1->outer_ccb() : NULL;
const DInner_ccb *ic2 = (he2->is_on_inner_ccb()) ? he2->inner_ccb() : NULL;
const DOuter_ccb *oc2 = (ic2 == NULL) ? he2->outer_ccb() : NULL;
if (oc1 != oc2 || ic1 != ic2)
return (-1);
// Compute the distance between the two halfedges.
unsigned int dist = p_arr->_halfedge_distance (he1, he2);
return (static_cast<int> (dist));
}
/*!
* Determine whether a given query halfedge lies in the interior of a new
* face we are about to create, by connecting it with another halfedge
* using a given x-monotone curve.
* \param prev1 A handle for the query halfedge.
* \param prev2 The other halfedge we are about to connect with prev1.
* \param cv The x-monotone curve we use to connect prev1 and prev2.
* \pre prev1 and prev2 belong to the same connected component, and by
* connecting them using cv we form a new face.
* \return (true) if prev1 lies in the interior of the face we are about
* to create, (false) otherwise - in which case prev2 must lie
* inside this new face.
*/
bool is_inside_new_face (Halfedge_handle prev1,
Halfedge_handle prev2,
const X_monotone_curve_2& cv) const
{
return (p_arr->_is_inside_new_face (p_arr->_halfedge (prev1),
p_arr->_halfedge (prev2),
cv));
}
/*!
* Check if the given vertex represents one of the ends of a given curve.
* \param v The vertex.
* \param cv The curve.
* \param ind ARR_MIN_END if we refer to cv's minimal end;
* ARR_MAX_END if we refer to its maximal end.
* \param ps_x The boundary condition of the curve end in x.
* \param ps_y The boundary condition of the curve end in y.
* \return Whether v represents the left (or right) end of cv.
*/
bool are_equal (Vertex_const_handle v,
const X_monotone_curve_2& cv, Arr_curve_end ind,
Arr_parameter_space ps_x, Arr_parameter_space ps_y) const
{
return (p_arr->topology_traits()->are_equal (p_arr->_vertex (v),
cv, ind, ps_x, ps_y));
}
/*!
* Check whether the given halfedge lies on the outer boundary of its
* incident face.
* \param he The given halfedge.
* \return (true) in case he lies on the outer boundary of its incident face;
* (false) if he lies on a hole inside this face.
*/
bool is_on_outer_boundary (Halfedge_const_handle he) const
{
const DHalfedge *p_he = p_arr->_halfedge (he);
return (! p_he->is_on_inner_ccb());
}
/*!
* Check whether the given halfedge lies on the inner boundary of its
* incident face.
* \param he The given halfedge.
* \return (true) in case he lies on a hole inside its incident face;
* (false) if he lies on the outer boundary of this face.
*/
bool is_on_inner_boundary (Halfedge_const_handle he) const
{
const DHalfedge *p_he = p_arr->_halfedge (he);
return (p_he->is_on_inner_ccb());
}
/*!
* Create a new vertex and associate it with the given point.
* \param p The point.
* \return A handle for the newly created vertex.
*/
Vertex_handle create_vertex (const Point_2& p)
{
DVertex* v = p_arr->_create_vertex (p);
CGAL_assertion (v != NULL);
return (p_arr->_handle_for (v));
}
/*!
* Create a new boundary vertex.
* \param cv The curve incident to the boundary.
* \param ind The relevant curve-end.
* \param ps_x The boundary condition in x.
* \param by The boundary condition in y.
* \param notify Should we send a notification to the topology traits
* on the creation of the vertex (true by default).
* \pre Either ps_x or by does not equal ARR_INTERIOR.
* \return A handle for the newly created vertex.
*/
Vertex_handle create_boundary_vertex (const X_monotone_curve_2& cv,
Arr_curve_end ind,
Arr_parameter_space ps_x,
Arr_parameter_space ps_y,
bool notify = true)
{
DVertex *v = p_arr->_create_boundary_vertex (cv, ind, ps_x, ps_y);
CGAL_assertion (v != NULL);
// Notify the topology traits on the creation of the boundary vertex.
if (notify)
{
p_arr->topology_traits()->notify_on_boundary_vertex_creation(v, cv, ind,
ps_x, ps_y);
}
return (p_arr->_handle_for (v));
}
/*!
* Locate the arrangement features that will be used for inserting the
* given curve end, which has a boundary condition, and set a proper vertex
* there.
* \param f The face that contains the curve end.
* \param cv The x-monotone curve.
* \param ind The curve end.
* \param ps_x The boundary condition at the x-coordinate.
* \param ps_y The boundary condition at the y-coordinate.
* \return A pair of <Vertex_handle, Halfedge_handle>:
* The first element is the vertex that corresponds to the curve end.
* The second is its predecessor halfedge (if valid).
*/
std::pair<Vertex_handle, Halfedge_handle>
place_and_set_curve_end (Face_handle f,
const X_monotone_curve_2& cv, Arr_curve_end ind,
Arr_parameter_space ps_x, Arr_parameter_space ps_y)
{
DHalfedge *pred;
DVertex *v = p_arr->_place_and_set_curve_end (p_arr->_face (f), cv, ind,
ps_x, ps_y, &pred);
if (pred == NULL)
// No predecessor halfedge, return just the vertex:
return (std::make_pair (p_arr->_handle_for(v), Halfedge_handle()));
// Return a pair of the vertex and predecessor halfedge:
return (std::make_pair (p_arr->_handle_for(v), p_arr->_handle_for(pred)));
}
/*!
* Insert an x-monotone curve into the arrangement, where the end vertices
* are given by the target points of two given halfedges.
* The two halfedges should be given such that in case a new face is formed,
* it will be the incident face of the halfedge directed from the first
* vertex to the second vertex.
* \param cv the given curve.
* \param prev1 The reference halfedge for the first vertex.
* \param prev2 The reference halfedge for the second vertex.
* \param res The comparsion result between the points associated with the
* target vertex of prev and the target vertex of prev2.
* \param new_face Output - whether a new face has been created.
* \return A handle for one of the halfedges corresponding to the inserted
* curve directed from prev1's target to prev2's target.
* In case a new face has been created, it is given as the incident
* face of this halfedge.
*/
Halfedge_handle insert_at_vertices_ex (const X_monotone_curve_2& cv,
Halfedge_handle prev1,
Halfedge_handle prev2,
Comparison_result res,
bool& new_face)
{
DHalfedge* he = p_arr->_insert_at_vertices (cv,
p_arr->_halfedge (prev1),
p_arr->_halfedge (prev2),
res, new_face);
CGAL_assertion (he != NULL);
return (p_arr->_handle_for (he));
}
/*!
* Insert an x-monotone curve into the arrangement, such that one of its
* endpoints corresponds to a given arrangement vertex, given the exact
* place for the curve in the circular list around this vertex. The other
* endpoint corrsponds to a free vertex (a newly created vertex or an
* isolated vertex).
* \param cv The given x-monotone curve.
* \param prev The reference halfedge. We should represent cv as a pair
* of edges, one of them should become prev's successor.
* \param v The free vertex that corresponds to the other endpoint.
* \param res The comparsion result between the points associated with
* the target vertex of prev and the vertex v.
* \return A handle to one of the halfedges corresponding to the inserted
* curve, whose target is the vertex v.
*/
Halfedge_handle insert_from_vertex_ex (const X_monotone_curve_2& cv,
Halfedge_handle prev,
Vertex_handle v,
Comparison_result res)
{
DVertex *p_v = p_arr->_vertex (v);
if (p_v->is_isolated())
{
// Remove the isolated vertex record, which will not be isolated any
// more.
DIso_vertex *iv = p_v->isolated_vertex();
DFace *f = iv->face();
f->erase_isolated_vertex (iv);
p_arr->_dcel().delete_isolated_vertex (iv);
}
DHalfedge* he =
p_arr->_insert_from_vertex (cv, p_arr->_halfedge (prev), p_v, res);
CGAL_assertion (he != NULL);
return (p_arr->_handle_for (he));
}
/*!
* Insert an x-monotone curve into the arrangement, such that both its
* endpoints correspond to free arrangement vertices (newly created vertices
* or existing isolated vertices), so a new hole is formed in the face
* that contains the two vertices.
* \param cv The given x-monotone curve.
* \param f The face containing the two end vertices.
* \param v1 The free vertex that corresponds to the left endpoint of cv.
* \param v2 The free vertex that corresponds to the right endpoint of cv.
* \param res The comparsion result between the points associated with the
* vertices v1 and v2.
* \return A handle to one of the halfedges corresponding to the inserted
* curve, directed from v1 to v2.
*/
Halfedge_handle insert_in_face_interior_ex (const X_monotone_curve_2& cv,
Face_handle f,
Vertex_handle v1,
Vertex_handle v2,
Comparison_result res)
{
DVertex *p_v1 = p_arr->_vertex (v1);
DVertex *p_v2 = p_arr->_vertex (v2);
if (p_v1->is_isolated())
{
// Remove the isolated vertex record, which will not be isolated any
// more.
DIso_vertex *iv1 = p_v1->isolated_vertex();
DFace *f1 = iv1->face();
f1->erase_isolated_vertex (iv1);
p_arr->_dcel().delete_isolated_vertex (iv1);
}
if (p_v2->is_isolated())
{
// Remove the isolated vertex record, which will not be isolated any
// more.
DIso_vertex *iv2 = p_v2->isolated_vertex();
DFace *f2 = iv2->face();
f2->erase_isolated_vertex (iv2);
p_arr->_dcel().delete_isolated_vertex (iv2);
}
DHalfedge* he = p_arr->_insert_in_face_interior (cv,
p_arr->_face (f),
p_v1,
p_v2,
res);
CGAL_assertion (he != NULL);
return (p_arr->_handle_for (he));
}
/*!
* Insert the given vertex as an isolated vertex inside the given face.
* \param f The face that should contain the isolated vertex.
* \param v The isolated vertex.
*/
void insert_isolated_vertex (Face_handle f, Vertex_handle v)
{
p_arr->_insert_isolated_vertex (p_arr->_face (f), p_arr->_vertex(v));
}
/*!
* Relocate all holes and isolated vertices to their proper position,
* immediately after a face has split due to the insertion of a new halfedge.
* In case insert_at_vertices_ex() was invoked and indicated that a new face
* has been created, this function should be called with the halfedge
* returned by insert_at_vertices_ex().
* \param new_he The new halfedge that caused the split, such that the new
* face lies to its left and the old face to its right.
*/
void relocate_in_new_face (Halfedge_handle new_he)
{
p_arr->_relocate_in_new_face (p_arr->_halfedge (new_he));
return;
}
void relocate_isolated_vertices_in_new_face (Halfedge_handle new_he)
{
p_arr->_relocate_isolated_vertices_in_new_face (p_arr->_halfedge(new_he));
return;
}
void relocate_holes_in_new_face (Halfedge_handle new_he)
{
p_arr->_relocate_holes_in_new_face (p_arr->_halfedge(new_he));
return;
}
/*!
* Move an outer CCB from one face to another.
* \param from_face The source face.
* \param to_face The destination face.
* \param ccb A CCB circulator that corresponds to component to move.
*/
void move_outer_ccb (Face_handle from_face, Face_handle to_face,
Ccb_halfedge_circulator ccb)
{
p_arr->_move_outer_ccb (p_arr->_face (from_face),
p_arr->_face (to_face),
p_arr->_halfedge (ccb));
return;
}
/*!
* Move an inner CCB from one face to another.
* \param from_face The source face.
* \param to_face The destination face.
* \param ccb A CCB circulator that corresponds to component to move.
*/
void move_inner_ccb (Face_handle from_face, Face_handle to_face,
Ccb_halfedge_circulator ccb)
{
p_arr->_move_inner_ccb (p_arr->_face (from_face),
p_arr->_face (to_face),
p_arr->_halfedge (ccb));
return;
}
/*!
* Move an isolated vertex from one face to another.
* \param from_face The source face.
* \param to_face The destination face.
* \param v The isolated vertex to move.
*/
void move_isolated_vertex (Face_handle from_face, Face_handle to_face,
Vertex_handle v)
{
p_arr->_move_isolated_vertex (p_arr->_face (from_face),
p_arr->_face (to_face),
p_arr->_vertex (v));
return;
}
/*!
* Remove an isolated vertex from its face.
* \param v The isolated vertex to remove.
*/
void remove_isolated_vertex_ex (Vertex_handle v)
{
CGAL_precondition (v->is_isolated());
DVertex *iso_v = p_arr->_vertex (v);
p_arr->_remove_isolated_vertex (iso_v);
return;
}
/*!
* Modify the point associated with a given vertex. The point may be
* geometrically different than the one currently associated with the vertex.
* \param v The vertex to modify.
* \param p The new point to associate with v.
* \return A handle for the modified vertex (same as v).
*/
Vertex_handle modify_vertex_ex (Vertex_handle v,
const Point_2& p)
{
p_arr->_modify_vertex (p_arr->_vertex (v),
p);
return (v);
}
/*!
* Modify the x-monotone curve associated with a given edge. The curve may be
* geometrically different than the one currently associated with the edge.
* \param e The edge to modify.
* \param cv The new x-monotone curve to associate with e.
* \return A handle for the modified edge (same as e).
*/
Halfedge_handle modify_edge_ex (Halfedge_handle e,
const X_monotone_curve_2& cv)
{
p_arr->_modify_edge (p_arr->_halfedge (e), cv);
return (e);
}
/*!
* Split a given edge into two at a given point, and associate the given
* x-monotone curves with the split edges.
* \param e The edge to split (one of the pair of twin halfegdes).
* \param p The split point.
* \param cv1 The curve that should be associated with the first split edge,
* whose source equals e's source and its target is p.
* \param cv2 The curve that should be associated with the second split edge,
* whose source is p and its target equals e's target.
* \return A handle for the first split halfedge, whose source equals the
* source of e, and whose target is the split point.
*/
Halfedge_handle split_edge_ex (Halfedge_handle e,
const Point_2& p,
const X_monotone_curve_2& cv1,
const X_monotone_curve_2& cv2)
{
DHalfedge* he = p_arr->_split_edge (p_arr->_halfedge (e), p, cv1, cv2);
CGAL_assertion (he != NULL);
return (p_arr->_handle_for (he));
}
/*!
* Split a given edge into two at the given vertex, and associate the given
* x-monotone curves with the split edges.
* \param e The edge to split (one of the pair of twin halfegdes).
* \param v The split vertex.
* \param cv1 The curve that should be associated with the first split edge,
* whose source equals e's source and its target is v's point.
* \param cv2 The curve that should be associated with the second split edge,
* whose source is v's point and its target equals e's target.
* \return A handle for the first split halfedge, whose source equals the
* source of e, and whose target is the split vertex v.
*/
Halfedge_handle split_edge_ex (Halfedge_handle e,
Vertex_handle v,
const X_monotone_curve_2& cv1,
const X_monotone_curve_2& cv2)
{
DHalfedge* he = p_arr->_split_edge (p_arr->_halfedge (e),
p_arr->_vertex (v),
cv1, cv2);
CGAL_assertion (he != NULL);
return (p_arr->_handle_for (he));
}
/*!
* Split a fictitious edge at the given vertex.
* \param e The edge to split (one of the pair of twin halfegdes).
* \param v The split vertex.
* \return A handle for the first split halfedge, whose source equals the
* source of e, and whose target is the split vertex v.
*/
Halfedge_handle split_fictitious_edge (Halfedge_handle e, Vertex_handle v)
{
CGAL_precondition (e->is_fictitious());
DHalfedge *he =
p_arr->topology_traits()->split_fictitious_edge (p_arr->_halfedge (e),
p_arr->_vertex (v));
return (p_arr->_handle_for (he));
}
/*!
* Remove a pair of twin halfedges from the arrangement.
* \param e A handle for one of the halfedges to be removed.
* \param remove_source Should the source vertex of e be removed if it
* becomes isolated (true by default).
* \param remove_target Should the target vertex of e be removed if it
* becomes isolated (true by default).
* \pre In case the removal causes the creation of a new hole, e should
* point at this hole.
* \return A handle for the remaining face.
*/
Face_handle remove_edge_ex (Halfedge_handle e,
bool remove_source = true,
bool remove_target = true)
{
DFace* f = p_arr->_remove_edge (p_arr->_halfedge (e),
remove_source, remove_target);
CGAL_assertion (f != NULL);
return (p_arr->_handle_for (f));
}
/*!
* Check if the two given halfedges lie on the same inner component.
* \param e1 A handle for the first halfedge.
* \param e2 A handle for the second halfedge.
* \return Whether e1 and e2 lie on the same inner component.
*/
bool are_on_same_inner_component (Halfedge_handle e1, Halfedge_handle e2)
{
DHalfedge *he1 = p_arr->_halfedge (e1);
DHalfedge *he2 = p_arr->_halfedge (e2);
const DInner_ccb *ic1 = (he1->is_on_inner_ccb()) ? he1->inner_ccb() : NULL;
if (ic1 == NULL)
return (false);
const DInner_ccb *ic2 = (he2->is_on_inner_ccb()) ? he2->inner_ccb() : NULL;
return (ic1 == ic2);
}
/*!
* Check if the two given halfedges lie on the same outer component.
* \param e1 A handle for the first halfedge.
* \param e2 A handle for the second halfedge.
* \return Whether e1 and e2 lie on the same outer component.
*/
bool are_on_same_outer_component (Halfedge_handle e1, Halfedge_handle e2)
{
DHalfedge *he1 = p_arr->_halfedge (e1);
DHalfedge *he2 = p_arr->_halfedge (e2);
const DOuter_ccb *oc1 = (he1->is_on_outer_ccb()) ? he1->outer_ccb() : NULL;
if (oc1 == NULL)
return (false);
const DOuter_ccb *oc2 = (he2->is_on_outer_ccb()) ? he2->outer_ccb() : NULL;
return (oc1 == oc2);
}
//@}
/// \name Traversal methods for the BOOST graph traits.
//@{
/*! \class
* An iterator for traversing all arrangement vertices, including vertices
* at infinity (not including fictitious vertices).
*/
typedef typename Arrangement_2::_Is_valid_vertex Is_valid_vertex;
typedef typename Arrangement_2::_Valid_vertex_iterator Valid_vertex_iterator;
/*! Get an iterator for the first valid arrangement vertex. */
Valid_vertex_iterator valid_vertices_begin()
{
return (Valid_vertex_iterator
(p_arr->topology_traits()->dcel().vertices_begin(),
p_arr->topology_traits()->dcel().vertices_end(),
Is_valid_vertex (p_arr->topology_traits())));
}
/*! Get a past-the-end iterator for the valid arrangement vertices. */
Valid_vertex_iterator valid_vertices_end()
{
return (Valid_vertex_iterator
(p_arr->topology_traits()->dcel().vertices_end(),
p_arr->topology_traits()->dcel().vertices_end(),
Is_valid_vertex (p_arr->topology_traits())));
}
/*! Get the number of valid arrangement vertices. */
Size number_of_valid_vertices () const
{
return (p_arr->topology_traits()->number_of_valid_vertices());
}
//@}
/// \name Functions used by the arrangement reader and writer.
//@{
typedef typename Arrangement_2::Dcel Dcel;
typedef typename Arrangement_2::DVertex_const_iter Dcel_vertex_iterator;
typedef typename Arrangement_2::DEdge_const_iter Dcel_edge_iterator;
typedef typename Arrangement_2::DFace_const_iter Dcel_face_iterator;
typedef typename Arrangement_2::DOuter_ccb_const_iter
Dcel_outer_ccb_iterator;
typedef typename Arrangement_2::DInner_ccb_const_iter
Dcel_inner_ccb_iterator;
typedef typename Arrangement_2::DIso_vertex_const_iter
Dcel_iso_vertex_iterator;
typedef DVertex Dcel_vertex;
typedef DHalfedge Dcel_halfedge;
typedef DFace Dcel_face;
typedef DOuter_ccb Dcel_outer_ccb;
typedef DInner_ccb Dcel_inner_ccb;
typedef DIso_vertex Dcel_isolated_vertex;
/*!
* Get the arrangement DCEL.
*/
const Dcel& dcel () const
{
return (p_arr->_dcel());
}
/*!
* Clear the entire arrangment.
*/
void clear_all ()
{
p_arr->clear();
p_arr->_dcel().delete_all();
return;
}
/*!
* Create a new vertex.
* \param p A pointer to the point (may be NULL in case of a vertex at
* infinity).
* \param ps_x The boundary condition at x.
* \param ps_y The boundary condition at y.
* \return A pointer to the created DCEL vertex.
*/
Dcel_vertex* new_vertex (const Point_2 *p,
Arr_parameter_space ps_x, Arr_parameter_space ps_y)
{
Dcel_vertex *new_v = p_arr->_dcel().new_vertex();
if (p != NULL)
{
typename Dcel::Vertex::Point *p_pt = p_arr->_new_point(*p);
new_v->set_point (p_pt);
}
else
{
CGAL_precondition (p_arr->is_unbounded(ps_x, ps_y));
new_v->set_point (NULL);
}
new_v->set_boundary (ps_x, ps_y);
return (new_v);
}
/*!
* Create a new edge (halfedge pair), associated with the given curve.
* \param cv A pointer to the x-monotone curve (may be NULL in case of
* a fictitious edge).
* \return A pointer to one of the created DCEL halfedge.
*/
Dcel_halfedge* new_edge (const X_monotone_curve_2 *cv)
{
Dcel_halfedge *new_he = p_arr->_dcel().new_edge();
if (cv != NULL)
{
typename Dcel::Halfedge::X_monotone_curve *p_cv = p_arr->_new_curve(*cv);
new_he->set_curve (p_cv);
}
else
{
new_he->set_curve (NULL);
}
return (new_he);
}
/*!
* Create a new face.
* \return A pointer to the created DCEL face.
*/
Dcel_face* new_face ()
{
return (p_arr->_dcel().new_face());
}
/*!
* Create a new outer CCB.
* \return A pointer to the created DCEL outer CCB.
*/
Dcel_outer_ccb* new_outer_ccb ()
{
return (p_arr->_dcel().new_outer_ccb());
}
/*!
* Create a new inner CCB.
* \return A pointer to the created DCEL inner CCB.
*/
Dcel_inner_ccb* new_inner_ccb ()
{
return (p_arr->_dcel().new_inner_ccb());
}
/*!
* Create a new isolated vertex.
* \return A pointer to the created DCEL isolated vertex.
*/
Dcel_isolated_vertex* new_isolated_vertex ()
{
return (p_arr->_dcel().new_isolated_vertex());
}
/*!
* Update the topology traits after the DCEL has been updated.
*/
void dcel_updated()
{
p_arr->topology_traits()->dcel_updated();
return;
}
//@}
};
CGAL_END_NAMESPACE
#endif
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