mirror of https://github.com/CGAL/cgal
wein: fixed vertical-decomposition
This commit is contained in:
Efi Fogel
parent
39ab15f6d6
commit
f46a4b71aa
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@ -0,0 +1,106 @@
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// Copyright (c) 2007 Tel-Aviv University (Israel).
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// All rights reserved.
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//
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// This file is part of CGAL (www.cgal.org); you may redistribute it under
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// the terms of the Q Public License version 1.0.
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// See the file LICENSE.QPL distributed with CGAL.
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//
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// Licensees holding a valid commercial license may use this file in
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||||
// accordance with the commercial license agreement provided with the software.
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||||
//
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||||
// This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
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// WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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//
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// $URL$
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// $Id$
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//
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//
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// Author(s) : Ron Wein <wein@post.tau.ac.il>
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#ifndef CGAL_ARR_BOUNDED_PLANAR_VERT_DEOCMP_HELPER_H
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#define CGAL_ARR_BOUNDED_PLANAR_VERT_DEOCMP_HELPER_H
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/*! \file
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* Definition of the Arr_bounded_planar_vert_decomp_helper class-template.
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*/
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CGAL_BEGIN_NAMESPACE
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#include <CGAL/Sweep_line_empty_visitor.h>
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/*! \class Arr_bounded_planar_vert_decomp_helper
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* A helper class for the vertical decomposition sweep-line visitor, suitable
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* for an Arrangement_on_surface_2 instantiated with a topology-traits class
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* for bounded curves in the plane.
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*/
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template <class Traits_, class Arrangement_>
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class Arr_bounded_planar_vert_decomp_helper
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{
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public:
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typedef Traits_ Traits_2;
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typedef Arrangement_ Arrangement_2;
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typedef typename Arrangement_2::Face_const_handle Face_const_handle;
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typedef Sweep_line_empty_visitor<Traits_2> Base_visitor;
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typedef typename Base_visitor::Event Event;
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typedef typename Base_visitor::Subcurve Subcurve;
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protected:
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typedef typename Arrangement_2::Topology_traits Topology_traits;
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// Data members:
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const Topology_traits *m_top_traits; // The topology-traits class.
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Face_const_handle m_unb_face; // The unbounded arrangement face.
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public:
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/*!
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* Constructor.
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* \param arr The arrangement.
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*/
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Arr_bounded_planar_vert_decomp_helper (const Arrangement_2 *arr) :
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m_top_traits (arr->topology_traits())
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{}
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/// \name Notification functions.
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//@{
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/* A notification issued before the sweep process starts. */
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void before_sweep ()
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{
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// Get the unbounded face.
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m_unb_face = Face_const_handle (m_top_traits->unbounded_face());
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}
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/*!
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* A notification invoked after the sweep-line finishes handling the given
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* event.
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*/
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void after_handle_event (Event* event)
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{
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return;
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}
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//@}
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/*! Get the current top object. */
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CGAL::Object top_object () const
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{
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// Wrap the unbounded face by a CGAL object.
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return (CGAL::make_object (m_unb_face));
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}
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/*! Get the current bottom object. */
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CGAL::Object bottom_object () const
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{
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// Wrap the unbounded face by a CGAL object.
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return (CGAL::make_object (m_unb_face));
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}
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};
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CGAL_END_NAMESPACE
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#endif
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@ -0,0 +1,105 @@
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// Copyright (c) 2007 Tel-Aviv University (Israel).
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// All rights reserved.
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//
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// This file is part of CGAL (www.cgal.org); you may redistribute it under
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// the terms of the Q Public License version 1.0.
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// See the file LICENSE.QPL distributed with CGAL.
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//
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// Licensees holding a valid commercial license may use this file in
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// accordance with the commercial license agreement provided with the software.
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//
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// This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
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// WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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//
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// $URL$
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// $Id$
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//
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// Author(s) : Ron Wein <wein@post.tau.ac.il>
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// Efi Fogel <efif@post.tau.ac.il>
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//
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#ifndef CGAL_ARR_SPHERICAL_VERT_DECOMP_HELPER_H
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#define CGAL_ARR_SPHERICAL_VERT_DECOMP_HELPER_H
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/*! \file
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* Definition of the Arr_spherical_vert_decomp_helper class-template.
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*/
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CGAL_BEGIN_NAMESPACE
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#include <CGAL/Sweep_line_empty_visitor.h>
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/*! \class Arr_spherical_vert_decomp_helper
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* A helper class for the vertical decomposition sweep-line visitor, suitable
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* for an Arrangement_on_surface_2 instantiated with a topology-traits class
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* for bounded curves in the plane.
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*/
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template <class Traits_, class Arrangement_>
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class Arr_spherical_vert_decomp_helper
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{
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public:
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typedef Traits_ Traits_2;
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typedef Arrangement_ Arrangement_2;
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typedef typename Arrangement_2::Face_const_handle Face_const_handle;
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typedef Sweep_line_empty_visitor<Traits_2> Base_visitor;
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typedef typename Base_visitor::Event Event;
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typedef typename Base_visitor::Subcurve Subcurve;
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protected:
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typedef typename Arrangement_2::Topology_traits Topology_traits;
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const Topology_traits *m_top_traits; // The topology traits.
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Face_const_handle m_north_face; // Current north face.
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public:
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/*! Constructor.
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* \param arr The arrangement.
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*/
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Arr_spherical_batched_pl_helper(const Arrangement_2 *arr) :
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m_top_traits(arr->topology_traits())
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{}
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/// \name Notification functions.
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//@{
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/*! A notification issued before the sweep process starts. */
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void before_sweep()
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{
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// Get the spherical face of the arrangement.
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m_north_face = Face_handle_red(m_top_traits->spherical_face());
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return;
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}
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/*!
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* A notification invoked after the sweep-line finishes handling the given
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* event.
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*/
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void after_handle_event(Event * event)
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{
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return;
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}
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//@}
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/*! Get the current top object. */
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CGAL::Object top_object () const
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{
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// Wrap the north face with a CGAL object.
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return (m_north_face);
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}
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/*! Get the current bottom object. */
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CGAL::Object bottom_object () const
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{
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// Wrap the north face with a CGAL object.
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return (m_north_face);
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}
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};
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CGAL_END_NAMESPACE
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#endif
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@ -0,0 +1,186 @@
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// Copyright (c) 2007 Tel-Aviv University (Israel).
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// All rights reserved.
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//
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// This file is part of CGAL (www.cgal.org); you may redistribute it under
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// the terms of the Q Public License version 1.0.
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// See the file LICENSE.QPL distributed with CGAL.
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//
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// Licensees holding a valid commercial license may use this file in
|
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// accordance with the commercial license agreement provided with the software.
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||||
//
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// This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
|
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// WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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//
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// $URL$
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// $Id$
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//
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//
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// Author(s) : Ron Wein <wein@post.tau.ac.il>
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#ifndef CGAL_ARR_UNB_PLANAR_VERT_DECOMP_HELPER_H
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#define CGAL_ARR_UNB_PLANAR_VERT_DECOMP_HELPER_H
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/*! \file
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* Definition of the Arr_unb_planar_vert_decomp_helper class-template.
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*/
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CGAL_BEGIN_NAMESPACE
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#include <CGAL/Sweep_line_empty_visitor.h>
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/*! \class Arr_unb_planar_vert_decomp_helper
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* A helper class for the vertical decomposition sweep-line visitor, suitable
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* for an Arrangement_on_surface_2 instantiated with a topology-traits class
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* for unbounded curves in the plane.
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*/
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template <class Traits_, class Arrangement_>
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class Arr_unb_planar_vert_decomp_helper
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{
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public:
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typedef Traits_ Traits_2;
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typedef Arrangement_ Arrangement_2;
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typedef typename Arrangement_2::Face_const_handle Face_const_handle;
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typedef Sweep_line_empty_visitor<Traits_2> Base_visitor;
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typedef typename Base_visitor::Event Event;
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typedef typename Base_visitor::Subcurve Subcurve;
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protected:
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typedef typename Arrangement_2::Topology_traits Topology_traits;
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typedef typename Arrangement_2::Halfedge_const_handle Halfedge_const_handle;
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typedef typename Arrangement_2::Vertex_const_handle Vertex_const_handle;
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// Data members:
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const Topology_traits *m_top_traits; // The topology-traits class.
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Halfedge_const_handle m_top_fict; // The current top fictitious halfedge.
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Halfedge_const_handle m_bottom_fict; // The current bottom fictitious
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// halfedge.
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public:
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/*!
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* Constructor.
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* \param arr The arrangement.
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*/
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Arr_unb_planar_vert_decomp_helper (const Arrangement_2 *arr) :
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m_top_traits (arr->topology_traits())
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{}
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/// \name Notification functions.
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//@{
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/* A notification issued before the sweep process starts. */
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void before_sweep ();
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/*!
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* A notification invoked after the sweep-line finishes handling the given
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* event.
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*/
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void after_handle_event (Event* event);
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//@}
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/*! Get the current top object. */
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CGAL::Object top_object () const
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{
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// Wrap the top fictitious halfedge by a CGAL object.
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return (CGAL::make_object (m_top_fict));
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}
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/*! Get the current bottom object. */
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CGAL::Object bottom_object () const
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{
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// Wrap the bottom fictitious halfedge by a CGAL object.
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return (CGAL::make_object (m_bottom_fict));
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}
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};
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//-----------------------------------------------------------------------------
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// Memeber-function definitions:
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//-----------------------------------------------------------------------------
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//-----------------------------------------------------------------------------
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// A notification issued before the sweep process starts.
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//
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template <class Tr, class Arr>
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void Arr_unb_planar_vert_decomp_helper<Tr, Arr>::before_sweep ()
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{
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// Initialize the fictitious halfedge lying on the top edge of the
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// bounding rectangle. We start from the leftmost halfedge, which is
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// incident to the top-left vertex and directed from right to left.
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Vertex_const_handle v_tl =
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Vertex_const_handle (m_top_traits->top_left_vertex());
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m_top_fict = v_tl->incident_halfedges();
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if (m_top_fict->direction() == LEFT_TO_RIGHT)
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m_top_fict = m_top_fict->next()->twin();
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CGAL_assertion_code (
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Vertex_const_handle v_tr =
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Vertex_const_handle (m_top_traits->top_right_vertex());
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);
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CGAL_assertion ((m_top_fict->source() == v_tr) ||
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(m_top_fict->source()->boundary_in_x() == NO_BOUNDARY &&
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m_top_fict->source()->boundary_in_y() == PLUS_INFINITY));
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// Initialize the fictitious halfedge lying on the bottom edge of the
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// bounding rectangle. We start from the leftmost halfedge, which is
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// incident to the bottom-left vertex and whose source is not at -oo.
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Vertex_const_handle v_bl =
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Vertex_const_handle (m_top_traits->bottom_left_vertex());
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m_bottom_fict = v_bl->incident_halfedges();
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if (m_bottom_fict->source()->boundary_in_x() == MINUS_INFINITY)
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m_bottom_fict = m_bottom_fict->next()->twin();
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CGAL_assertion_code (
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Vertex_const_handle v_br =
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Vertex_const_handle (m_top_traits->bottom_right_vertex());
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);
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CGAL_assertion ((m_bottom_fict->source() == v_br) ||
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(m_bottom_fict->source()->boundary_in_x() == NO_BOUNDARY &&
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m_bottom_fict->source()->boundary_in_y() == MINUS_INFINITY));
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return;
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}
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//-----------------------------------------------------------------------------
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// A notification invoked after the sweep-line finishes handling the given
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// event.
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//
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template <class Tr, class Arr>
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void Arr_unb_planar_vert_decomp_helper<Tr, Arr>::after_handle_event
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(Event* event)
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{
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// If the event is at infinity and occurs on the top edge of the fictitious
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// face (namely x is finite and y = +oo), we have to update the fictitious
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// halfedges we keep.
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if (event->is_finite())
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return;
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if (event->boundary_in_x() != NO_BOUNDARY)
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return;
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Boundary_type by = event->boundary_in_y();
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if (by == PLUS_INFINITY)
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{
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// Update the fictitious top halfedge.
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m_top_fict = m_top_fict->twin()->next()->twin();
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}
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else
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{
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CGAL_assertion (by == PLUS_INFINITY);
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// Update the fictitious bottom halfedge.
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m_bottom_fict = m_bottom_fict->prev();
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}
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return;
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}
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CGAL_END_NAMESPACE
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#endif
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@ -0,0 +1,328 @@
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// Copyright (c) 2007 Tel-Aviv University (Israel).
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// 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.
|
||||
//
|
||||
// $URL$
|
||||
// $Id$
|
||||
//
|
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//
|
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// Author(s) : Ron Wein <wein@post.tau.ac.il>
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#ifndef CGAL_ARR_VERT_DECOMP_SL_VISITOR_H
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#define CGAL_ARR_VERT_DECOMP_SL_VISITOR_H
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/*!
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* Definition of the Arr_vert_decomp_sl_visitor class-template.
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*/
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CGAL_BEGIN_NAMESPACE
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#include <CGAL/Object.h>
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/*! \class Arr_vert_decomp_sl_visitor
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* A sweep-line visitor for performing vertical decomposition on an
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* arrangement embedded on a surface.
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*/
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template <class Helper_, class OutputIterator_>
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class Arr_vert_decomp_sl_visitor :
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public Helper_::Base_visitor
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{
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public:
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typedef Helper_ Helper;
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typedef OutputIterator_ OutputIterator;
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typedef typename Helper::Traits_2 Traits_2;
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typedef typename Helper::Arrangement_2 Arrangement_2;
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typedef typename Helper::Base_visitor Base;
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typedef typename Helper::Event Event;
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typedef typename Helper::Subcurve Subcurve;
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typedef typename Arrangement_2::Vertex_const_handle Vertex_const_handle;
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typedef std::pair<CGAL::Object, CGAL::Object> Vert_pair;
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typedef std::pair<Vertex_const_handle, Vert_pair> Vert_entry;
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protected:
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typedef typename Base::Status_line_iterator Status_line_iterator;
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typedef typename Arrangement_2::Halfedge_const_handle Halfedge_const_handle;
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typedef typename Arrangement_2::Vertex_const_handle Vertex_const_handle;
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typedef typename Arrangement_2::Halfedge_around_vertex_const_circulator
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Halfedge_around_vertex_const_circulator;
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// Data members:
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Helper m_helper; // The helper class.
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const typename Arrangement_2::Geometry_traits_2 *m_traits;
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// The traits class.
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const Vertex_const_handle invalid_vh;
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// An invalid vertex handle.
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Vertex_const_handle m_prev_vh; // The previous vertex.
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CGAL::Object m_prev_obj_below; // The object this vertex sees below it.
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CGAL::Object m_prev_obj_above; // The object this vertex sees above it.
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OutputIterator *m_out; // An output iterator for the result.
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public:
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/*!
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* Constructor.
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* \param arr The arrangement.
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* \param oi A pointer to the output iterator that will store the result.
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*/
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Arr_vert_decomp_sl_visitor (const Arrangement_2 *arr,
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OutputIterator *oi) :
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m_helper (arr),
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m_traits (arr->geometry_traits()),
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invalid_vh(),
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m_out (oi)
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{}
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/* A notification issued before the sweep process starts. */
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void before_sweep ();
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/*!
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||||
* A notification invoked after the sweep-line finishes handling the given
|
||||
* event.
|
||||
* \param event The event.
|
||||
* \param above An iterator to the sweep-line subcurves lying right above
|
||||
* (or on) the event point.
|
||||
* \param on_above Whether the event is locates on the subcurve above it.
|
||||
*/
|
||||
bool after_handle_event (Event* event,
|
||||
Status_line_iterator above,
|
||||
bool on_above);
|
||||
|
||||
/*!
|
||||
* A notification issued when the sweep process is over.
|
||||
*/
|
||||
void after_sweep ();
|
||||
};
|
||||
|
||||
//-----------------------------------------------------------------------------
|
||||
// Memeber-function definitions:
|
||||
//-----------------------------------------------------------------------------
|
||||
|
||||
//-----------------------------------------------------------------------------
|
||||
// A notification issued before the sweep process starts.
|
||||
//
|
||||
template <class Hlpr, class OutIt>
|
||||
void Arr_vert_decomp_sl_visitor<Hlpr, OutIt>::before_sweep ()
|
||||
{
|
||||
// Notify the helper that the sweep process now starts.
|
||||
m_helper.before_sweep();
|
||||
|
||||
// Set an invalid previous vertex.
|
||||
m_prev_vh = Vertex_const_handle();
|
||||
|
||||
return;
|
||||
}
|
||||
|
||||
//-----------------------------------------------------------------------------
|
||||
// A notification invoked after the sweep-line finishes handling the given
|
||||
// event.
|
||||
//
|
||||
template <class Hlpr, class OutIt>
|
||||
bool Arr_vert_decomp_sl_visitor<Hlpr, OutIt>::after_handle_event
|
||||
(Event* event,
|
||||
Status_line_iterator above, bool /* on_above */)
|
||||
{
|
||||
// Notify the helper on the event.
|
||||
m_helper.after_handle_event (event);
|
||||
|
||||
// We are only interested in events associated with finite points:
|
||||
if (! event->is_finite())
|
||||
return (true);
|
||||
|
||||
// Get the vertex handle associated with the current event (stored with
|
||||
// the point).
|
||||
Vertex_const_handle vh = event->point().vertex_handle();
|
||||
CGAL::Object obj_above, obj_below;
|
||||
|
||||
// Check the feature from above.
|
||||
if (above == this->status_line_end())
|
||||
{
|
||||
// There is no concrete subcurve above the current event point, so we use
|
||||
// the helper class to obtain the object above.
|
||||
obj_above = m_helper.top_object();
|
||||
}
|
||||
else
|
||||
{
|
||||
// We have a valid subcurve above the event: get its halfedge handle
|
||||
// and associate it with the vertex.
|
||||
obj_above =
|
||||
CGAL::make_object((*above)->last_curve().halfedge_handle());
|
||||
}
|
||||
|
||||
// Check if the previous vertex we handled has the same x-coordinate
|
||||
// as the current one (it lies vertically below the current vertex).
|
||||
const bool prev_same_x =
|
||||
(m_prev_vh != invalid_vh &&
|
||||
m_traits->compare_x_2_object() (vh->point(),
|
||||
m_prev_vh->point()) == EQUAL);
|
||||
|
||||
// Decrement the status-line iterator to reach the subcurve below the
|
||||
// event point. If the number of right subcurves associated with the
|
||||
// event is n_right, we decrement the iterator n_right times, then
|
||||
// check if it is possible to further decrement it.
|
||||
Status_line_iterator below = above;
|
||||
const int n_right = event->number_of_right_curves();
|
||||
int k;
|
||||
|
||||
for (k = 0; k < n_right; k++)
|
||||
--below;
|
||||
|
||||
if (below == this->status_line_begin())
|
||||
{
|
||||
if (prev_same_x)
|
||||
{
|
||||
// The previous vertex is vertically below the current vertex,
|
||||
// so we update their respective entries in the output map.
|
||||
// We first check if the two vertices are connected (by a vertical
|
||||
// segment) - if so, they "see" empty features.
|
||||
bool vert_connected = false;
|
||||
|
||||
if (! vh->is_isolated())
|
||||
{
|
||||
Halfedge_around_vertex_const_circulator circ, first;
|
||||
|
||||
first = circ = vh->incident_halfedges();
|
||||
do
|
||||
{
|
||||
if (circ->source() == m_prev_vh)
|
||||
vert_connected = true;
|
||||
++circ;
|
||||
} while (! vert_connected && circ != first);
|
||||
}
|
||||
|
||||
if (! vert_connected)
|
||||
{
|
||||
obj_below = CGAL::make_object(m_prev_vh);
|
||||
m_prev_obj_above = CGAL::make_object(vh);
|
||||
}
|
||||
else
|
||||
{
|
||||
obj_below = CGAL::Object();
|
||||
m_prev_obj_above = CGAL::Object();
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
// There is no concrete subcurve below the current event point, so we
|
||||
// use the helper class to obtain the object below.
|
||||
obj_below = m_helper.bottom_object();
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
// Decrement the iterator once more in order to reach the subcurve below
|
||||
// the current event.
|
||||
--below;
|
||||
|
||||
// If the previous event has the same x-coordinate as the current one,
|
||||
// we check whether it lies below or above the subcurve below. We do this
|
||||
// to distinguish between the following scenarios:
|
||||
//
|
||||
//
|
||||
// * *
|
||||
//
|
||||
// -------- x
|
||||
//
|
||||
// x ---------
|
||||
//
|
||||
if (prev_same_x &&
|
||||
(m_traits->compare_y_at_x_2_object()
|
||||
(m_prev_vh->point(),
|
||||
(*below)->last_curve().base()) != SMALLER))
|
||||
{
|
||||
// The previous vertex is vertically below the current vertex,
|
||||
// and above the subcurve that lies below vh. We therefore update
|
||||
// the respective entries in the output map accordingly.
|
||||
// We first check if the two vertices are connected (by a vertical
|
||||
// segment) - if so, they "see" empty features.
|
||||
bool vert_connected = false;
|
||||
|
||||
if (! vh->is_isolated())
|
||||
{
|
||||
Halfedge_around_vertex_const_circulator circ, first;
|
||||
|
||||
first = circ = vh->incident_halfedges();
|
||||
do
|
||||
{
|
||||
if (circ->source() == m_prev_vh)
|
||||
vert_connected = true;
|
||||
++circ;
|
||||
} while (! vert_connected && circ != first);
|
||||
}
|
||||
|
||||
if (! vert_connected)
|
||||
{
|
||||
obj_below = CGAL::make_object(m_prev_vh);
|
||||
m_prev_obj_above = CGAL::make_object(vh);
|
||||
}
|
||||
else
|
||||
{
|
||||
obj_below = CGAL::Object();
|
||||
m_prev_obj_above = CGAL::Object();
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
// Get the halfedge handle of the subcurve below the current event and
|
||||
// associate it with its vertex.
|
||||
obj_below =
|
||||
CGAL::make_object((*below)->last_curve().halfedge_handle());
|
||||
}
|
||||
}
|
||||
|
||||
// We can now create the entry for the previous vertex, as we are not
|
||||
// going to change the identity of the features below or above it.
|
||||
if (m_prev_vh != Vertex_const_handle())
|
||||
{
|
||||
*(*m_out) = Vert_entry (m_prev_vh, Vert_pair (m_prev_obj_below,
|
||||
m_prev_obj_above));
|
||||
++(*m_out);
|
||||
}
|
||||
|
||||
// We are done with the current vertex, but we cannot create the entry
|
||||
// yet - so we store it for the next event.
|
||||
m_prev_vh = vh;
|
||||
m_prev_obj_below = obj_below;
|
||||
m_prev_obj_above = obj_above;
|
||||
|
||||
// It is safe to deallocate the event.
|
||||
return (true);
|
||||
}
|
||||
|
||||
//-----------------------------------------------------------------------------
|
||||
// A notification issued when the sweep process is over.
|
||||
//
|
||||
template <class Hlpr, class OutIt>
|
||||
void Arr_vert_decomp_sl_visitor<Hlpr, OutIt>::after_sweep ()
|
||||
{
|
||||
// Create an entry for the last vertex (the xy-largest one).
|
||||
if (m_prev_vh != invalid_vh)
|
||||
{
|
||||
*(*m_out) = Vert_entry (m_prev_vh, Vert_pair (m_prev_obj_below,
|
||||
m_prev_obj_above));
|
||||
++(*m_out);
|
||||
}
|
||||
|
||||
return;
|
||||
}
|
||||
|
||||
CGAL_END_NAMESPACE
|
||||
|
||||
#endif
|
||||
Loading…
Reference in New Issue