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cgal/Linear_cell_complex/include/CGAL/Linear_cell_complex.h

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// Copyright (c) 2011 CNRS and LIRIS' Establishments (France).
// 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.
//
// $URL$
// $Id$
//
// Author(s) : Guillaume Damiand <guillaume.damiand@liris.cnrs.fr>
//
#ifndef CGAL_LINEAR_CELL_COMPLEX_H
#define CGAL_LINEAR_CELL_COMPLEX_H 1
#include <CGAL/Combinatorial_map.h>
#include <CGAL/Combinatorial_map_operations.h>
#include <CGAL/Combinatorial_map_constructors.h>
#include <CGAL/Linear_cell_complex_min_items.h>
#include <CGAL/Linear_cell_complex_traits.h>
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
namespace CGAL {
/** @file Linear_cell_complex.h
* Definition of a linear cell complex, i.e. a combinatorial map with points
* associated to all vertices.
*/
/** Linear_cell_complex class.
* The Linear_cell_complex a nD object with linear geometry, ie
* an nD combinatorial map with point associated to each vertex.
*/
template < unsigned int d_, unsigned int ambient_dim = d_,
class Traits_ = Linear_cell_complex_traits<d_>,
class Items_ = Linear_cell_complex_min_items<d_>,
class Alloc_ = CGAL_ALLOCATOR(int),
template<unsigned int,class,class,class>
class CMap = Combinatorial_map_base >
class Linear_cell_complex:
public CMap<d_,Linear_cell_complex<d_, ambient_dim, Traits_,
Items_, Alloc_>, Items_, Alloc_>
{
public:
typedef Linear_cell_complex<d_, ambient_dim,
Traits_, Items_, Alloc_> Self;
typedef Combinatorial_map_base<d_, Self, Items_, Alloc_> Base;
typedef Traits_ Traits;
typedef Items_ Items;
typedef Alloc_ Alloc;
static const unsigned int ambient_dimension = ambient_dim;
static const unsigned int dimension = Base::dimension;
typedef typename Base::Dart_handle Dart_handle;
typedef typename Base::Dart_const_handle Dart_const_handle;
typedef typename Base::Helper Helper;
typedef typename Traits::Point Point;
typedef typename Traits::Vector Vector;
typedef typename Traits::FT FT;
typedef typename Base::Dart_range Dart_range;
typedef typename Base::template Attribute_type<0>::type Vertex_attribute;
typedef typename Base::template Attribute_handle<0>::type
Vertex_attribute_handle;
typedef typename Base::template Attribute_const_handle<0>::type
Vertex_attribute_const_handle;
typedef typename Base::template Attribute_range<0>::type
Vertex_attribute_range;
typedef typename Base::template Attribute_const_range<0>::type
Vertex_attribute_const_range;
/// To use previous definition of create_dart methods.
using Base::create_dart;
/** Create a vertex attribute.
* @return an handle on the new attribute.
*/
#ifndef CGAL_CFG_NO_CPP0X_VARIADIC_TEMPLATES
template<typename ...Args>
Vertex_attribute_handle create_vertex_attribute(const Args&... args)
{ return Base::template create_attribute<0>(args...); }
#else
Vertex_attribute_handle create_vertex_attribute()
{ return Base::template create_attribute<0>(); }
template<typename T1>
Vertex_attribute_handle create_vertex_attribute(const T1& t1)
{ return Base::template create_attribute<0>(t1); }
template<typename T1, typename T2>
Vertex_attribute_handle create_vertex_attribute
(const T1& t1, const T2 &t2)
{ return Base::template create_attribute<0>(t1, t2); }
template<typename T1, typename T2, typename T3>
Vertex_attribute_handle create_vertex_attribute
(const T1& t1, const T2 &t2, const T3 &t3)
{ return Base::template create_attribute<0>(t1, t2, t3); }
template<typename T1, typename T2, typename T3, typename T4>
Vertex_attribute_handle create_vertex_attribute
(const T1& t1, const T2 &t2, const T3 &t3, const T4 &t4)
{ return Base::template create_attribute<0>(t1, t2, t3, t4); }
template<typename T1, typename T2, typename T3, typename T4, typename T5>
Vertex_attribute_handle create_vertex_attribute
(const T1& t1, const T2 &t2, const T3 &t3, const T4 &t4,
const T5 &t5)
{ return Base::template create_attribute<0>(t1, t2, t3, t4, t5); }
template<typename T1, typename T2, typename T3, typename T4, typename T5,
typename T6>
Vertex_attribute_handle create_vertex_attribute
(const T1& t1, const T2 &t2, const T3 &t3, const T4 &t4,
const T5 &t5, const T6 &t6)
{ return Base::template create_attribute<0>(t1, t2, t3, t4, t5, t6); }
template<typename T1, typename T2, typename T3, typename T4, typename T5,
typename T6, typename T7>
Vertex_attribute_handle create_vertex_attribute
(const T1& t1, const T2 &t2, const T3 &t3, const T4 &t4,
const T5 &t5, const T6 &t6, const T7 &t7)
{ return Base::template create_attribute<0>(t1, t2, t3, t4, t5, t6, t7); }
template<typename T1, typename T2, typename T3, typename T4, typename T5,
typename T6, typename T7, typename T8>
Vertex_attribute_handle create_vertex_attribute
(const T1& t1, const T2 &t2, const T3 &t3, const T4 &t4,
const T5 &t5, const T6 &t6, const T7 &t7, const T8 &t8)
{ return Base::template create_attribute<0>(t1, t2, t3, t4, t5, t6, t7,
t8); }
template<typename T1, typename T2, typename T3, typename T4, typename T5,
typename T6, typename T7, typename T8, typename T9>
Vertex_attribute_handle create_vertex_attribute
(const T1& t1, const T2 &t2, const T3 &t3, const T4 &t4,
const T5 &t5, const T6 &t6, const T7 &t7, const T8 &t8, const T9 &t9)
{ return Base::template create_attribute<0>(t1, t2, t3, t4, t5, t6, t7,
t8, t9); }
#endif // CGAL_CFG_NO_CPP0X_VARIADIC_TEMPLATES
/**
* Create a new dart associated with an handle through an attribute.
* @param ahandle the point handle to associated with the dart.
* @return a Dart_handle on the new dart.
*/
Dart_handle create_dart(Vertex_attribute_handle ahandle)
{
Dart_handle res = create_dart();
set_vertex_attribute_of_dart(res,ahandle);
return res;
}
/** Create a new dart associated with a point.
* @param apoint the point to associated with the dart.
* @return a Dart_handle on the new dart.
*/
Dart_handle create_dart(const Point& apoint)
{ return create_dart(create_vertex_attribute(apoint)); }
/** Erase a given vertex attribute.
* @param ahandle the handle to the vertex attribute to erase.
*/
void erase_vertex_attribute(Vertex_attribute_handle ahandle)
{ Base::template erase_attribute<0>(ahandle); }
/** Set the vertex attribute of the given dart.
* @param adart a dart.
* @param ah the attribute to set.
*/
void set_vertex_attribute_of_dart(Dart_handle adart,
Vertex_attribute_handle ah)
{
return CGAL::internal::Set_i_attribute_of_dart_functor<Self, 0>::
run(this, adart,ah);
}
/** Set the vertex attribute of all the darts of the vertex.
* @param adart a dart of the vertex.
* @param ah the attribute to set.
*/
void set_vertex_attribute(Dart_handle adart,
Vertex_attribute_handle ah)
{ return CGAL::Set_i_attribute_functor<Self, 0>::run(this, adart,ah); }
/// @return the Vertex_attribute_range for all vertex_attributes.
Vertex_attribute_range& vertex_attributes()
{ return this->template attributes<0>(); }
/// @return the Vertex_attribute_const_range for all vertex_attributes.
Vertex_attribute_const_range& vertex_attributes() const
{ return this->template attributes<0>(); }
/// @return the size of the vertex_attribute container.
typename Base::size_type number_of_vertex_attributes() const
{ return Base::template number_of_attributes<0>(); }
/// Get the vertex_attribute associated with a dart.
/// @param a dart
/// @return the vertex_attribute.
static Vertex_attribute_handle vertex_attribute(Dart_handle adart)
{
CGAL_assertion(adart!=NULL);
return adart->template attribute<0>();
}
/// Get the vertex_attribute associated with a const dart.
/// @param a dart
/// @return the vertex_const_attribute.
static Vertex_attribute_const_handle vertex_attribute(Dart_const_handle
adart)
{
CGAL_assertion(adart!=NULL);
return adart->template attribute<0>();
}
/// Get the point associated with a dart.
/// @param a dart
/// @return the point.
static Point& point(Dart_handle adart)
{
CGAL_assertion(adart!=NULL && adart->template attribute<0>()!=NULL );
return adart->template attribute<0>()->point();
}
/// Get the point associated with a const dart.
/// @param a dart
/// @return the point.
static const Point& point(Dart_const_handle adart)
{
CGAL_assertion(adart!=NULL && adart->template attribute<0>()!=NULL );
return adart->template attribute<0>()->point();
}
/** Test if the lcc is valid.
* A Linear_cell_complex is valid if it is a valid Combinatorial_map with
* an attribute associated to each dart.
* @return true iff the map is valid.
*/
bool is_valid() const
{
bool valid = Base::is_valid();
for (typename Dart_range::const_iterator it(this->darts().begin()),
itend(this->darts().end()); valid && it != itend; ++it)
{
if ( vertex_attribute(it) == NULL )
{
std::cerr << "Map not valid: dart "<<&(*it)
<<" does not have a vertex."<< std::endl;
valid = false;
}
}
return valid;
}
/** test if the two given facets have the same geometry
* @return true iff the two facets have the same geometry.
*/
bool are_facets_same_geometry(Dart_const_handle d1,
Dart_const_handle d2) const
{
typename Base::template Dart_of_orbit_range<1>::const_iterator
it1(*this,d1);
typename Base::template Dart_of_orbit_range<0>::const_iterator
it2(*this,d2);
bool samegeometry = true;
for ( ; samegeometry && it1.cont() && it2.cont(); ++it1, ++it2)
{
if ( it2->other_extremity()!=NULL &&
point(it1)!=point(it2->other_extremity()) )
samegeometry = false;
}
if ( it1.cont() != it2.cont() ) samegeometry = false;
return samegeometry;
}
/// Sew3 the marked facets having same geometry
/// (a facet is considered marked if one of its dart is marked).
unsigned int sew3_same_facets(int AMark)
{
unsigned int res = 0;
std::map<Point, std::vector<Dart_handle> > one_dart_per_facet;
int mymark = this->get_new_mark();
CGAL_assertion( mymark!=-1 );
// First we fill the std::map by one dart per facet, and by using
// the minimal point as index.
for (typename Dart_range::iterator it(this->darts().begin()),
itend(this->darts().end()); it!=itend; ++it )
{
if ( !this->is_marked(it, mymark) && this->is_marked(it, AMark) )
{
Point min_point=point(it);
Dart_handle min_dart = it;
this->mark(it, mymark);
typename Base::template
Dart_of_orbit_range<1>::iterator it2(*this,it);
++it2;
for ( ; it2.cont(); ++it2 )
{
Point cur_point=point(it2);
this->mark(it2, mymark);
if ( cur_point < min_point )
{
min_point = cur_point;
min_dart = it2;
}
}
one_dart_per_facet[min_point].push_back(min_dart);
}
else
this->mark(it, mymark);
}
// Second we run through the map: candidates for sew3 have necessary the
// same minimal point.
typename std::map<Point, std::vector<Dart_handle> >::iterator
itmap=one_dart_per_facet.begin(),
itmapend=one_dart_per_facet.end();
for ( ; itmap!=itmapend; ++itmap )
{
for ( typename std::vector<Dart_handle>::iterator
it1=(itmap->second).begin(),
it1end=(itmap->second).end(); it1!=it1end; ++it1 )
{
typename std::vector<Dart_handle>::iterator it2=it1;
for ( ++it2; it2!= it1end; ++it2 )
{
if ( *it1!=*it2 && (*it1)->is_free(3) &&
(*it2)->is_free(3) &&
are_facets_same_geometry(*it1,(*it2)->beta(0)) )
{
++res;
this->template sew<3>(*it1,(*it2)->beta(0));
}
}
}
}
CGAL_assertion( this->is_whole_map_marked(mymark) );
this->free_mark(mymark);
return res;
}
/// Sew3 the facets having same geometry
/// (all the facets of the map are considered)
unsigned int sew3_same_facets()
{
int mark = this->get_new_mark();
this->negate_mark(mark);
unsigned int res=sew3_same_facets(mark);
this->free_mark(mark);
return res;
}
/** Create an edge given 2 Vertex_attribute_handle.
* @param h0 the first vertex handle.
* @param h1 the second vertex handle.
* @return the dart of the new edge incident to h0.
*/
Dart_handle make_segment(Vertex_attribute_handle h0,
Vertex_attribute_handle h1)
{
Dart_handle d1 = make_edge(*this);
set_vertex_attribute_of_dart(d1,h0);
set_vertex_attribute_of_dart(d1->beta(2),h1);
return d1;
}
/** Create a segment given 2 points.
* @param p0 the first point.
* @param p1 the second point.
* @return the dart of the new segment incident to p0.
*/
Dart_handle make_segment(const Point& p0,const Point& p1)
{
return make_segment(create_vertex_attribute(p0),
create_vertex_attribute(p1));
}
/** Create a triangle given 3 Vertex_attribute_handle.
* @param h0 the first vertex handle.
* @param h1 the second vertex handle.
* @param h2 the third vertex handle.
* @return the dart of the new triangle incident to h0.
*/
Dart_handle make_triangle(Vertex_attribute_handle h0,
Vertex_attribute_handle h1,
Vertex_attribute_handle h2)
{
Dart_handle d1 = make_combinatorial_polygon(*this,3);
set_vertex_attribute_of_dart(d1,h0);
set_vertex_attribute_of_dart(d1->beta(1),h1);
set_vertex_attribute_of_dart(d1->beta(0),h2);
return d1;
}
/** Create a triangle given 3 points.
* @param p0 the first point.
* @param p1 the second point.
* @param p2 the third point.
* @return the dart of the new triangle incident to p0.
*/
Dart_handle make_triangle(const Point& p0,
const Point& p1,
const Point& p2)
{
return make_triangle(create_vertex_attribute(p0),
create_vertex_attribute(p1),
create_vertex_attribute(p2));
}
/** Create a quadrangle given 4 Vertex_attribute_handle.
* @param h0 the first vertex handle.
* @param h1 the second vertex handle.
* @param h2 the third vertex handle.
* @param h3 the fourth vertex handle.
* @return the dart of the new quadrilateral incident to h0.
*/
Dart_handle make_quadrangle(Vertex_attribute_handle h0,
Vertex_attribute_handle h1,
Vertex_attribute_handle h2,
Vertex_attribute_handle h3)
{
Dart_handle d1 = make_combinatorial_polygon(*this,4);
set_vertex_attribute_of_dart(d1,h0);
set_vertex_attribute_of_dart(d1->beta(1),h1);
set_vertex_attribute_of_dart(d1->beta(1)->beta(1),h2);
set_vertex_attribute_of_dart(d1->beta(0),h3);
return d1;
}
/** Create a quadrangle given 4 points.
* @param p0 the first point.
* @param p1 the second point.
* @param p2 the third point.
* @param p3 the fourth point.
* @return the dart of the new quadrangle incident to p0.
*/
Dart_handle make_quadrangle(const Point& p0,
const Point& p1,
const Point& p2,
const Point& p3)
{
return make_quadrangle(create_vertex_attribute(p0),
create_vertex_attribute(p1),
create_vertex_attribute(p2),
create_vertex_attribute(p3));
}
/** Create a tetrahedron given 4 Vertex_attribute_handle.
* @param h0 the first vertex handle.
* @param h1 the second vertex handle.
* @param h2 the third vertex handle.
* @param h3 the fourth vertex handle.
* @return the dart of the new tetrahedron incident to h0 and to
* facet h0,h1,h2.
*/
Dart_handle make_tetrahedron(Vertex_attribute_handle h0,
Vertex_attribute_handle h1,
Vertex_attribute_handle h2,
Vertex_attribute_handle h3)
{
Dart_handle d1 = make_triangle(h0, h1, h2);
Dart_handle d2 = make_triangle(h1, h0, h3);
Dart_handle d3 = make_triangle(h1, h3, h2);
Dart_handle d4 = make_triangle(h3, h0, h2);
return make_combinatorial_tetrahedron(*this, d1, d2, d3, d4);
}
/** Create a tetrahedron given 4 points.
* @param p0 the first point.
* @param p1 the second point.
* @param p2 the third point.
* @param p3 the fourth point.
* @return the dart of the new tetrahedron incident to p0 and to
* facet p0,p1,p2.
*/
Dart_handle make_tetrahedron(const Point& p0,
const Point& p1,
const Point& p2,
const Point& p3)
{
return make_tetrahedron(create_vertex_attribute(p0),
create_vertex_attribute(p1),
create_vertex_attribute(p2),
create_vertex_attribute(p3));
}
/** Create an hexahedron given 8 Vertex_attribute_handle.
* (8 vertices, 12 edges and 6 facets)
* \verbatim
* 4----7
* /| /|
* 5----6 |
* | 3--|-2
* |/ |/
* 0----1
* \endverbatim
* @param h0 the first vertex handle.
* @param h1 the second vertex handle.
* @param h2 the third vertex handle.
* @param h3 the fourth vertex handle.
* @param h4 the fifth vertex handle.
* @param h5 the sixth vertex handle.
* @param h6 the seventh vertex handle.
* @param h7 the height vertex handle.
* @return the dart of the new hexahedron incident to h0 and to
* the facet (h0,h5,h6,h1).
*/
Dart_handle make_hexahedron(Vertex_attribute_handle h0,
Vertex_attribute_handle h1,
Vertex_attribute_handle h2,
Vertex_attribute_handle h3,
Vertex_attribute_handle h4,
Vertex_attribute_handle h5,
Vertex_attribute_handle h6,
Vertex_attribute_handle h7)
{
Dart_handle d1 = make_quadrangle(h0, h5, h6, h1);
Dart_handle d2 = make_quadrangle(h1, h6, h7, h2);
Dart_handle d3 = make_quadrangle(h2, h7, h4, h3);
Dart_handle d4 = make_quadrangle(h3, h4, h5, h0);
Dart_handle d5 = make_quadrangle(h0, h1, h2, h3);
Dart_handle d6 = make_quadrangle(h5, h4, h7, h6);
return make_combinatorial_hexahedron(*this, d1, d2, d3, d4, d5, d6);
}
/** Create an hexahedron given 8 points.
* \verbatim
* 4----7
* /| /|
* 5----6 |
* | 3--|-2
* |/ |/
* 0----1
* \endverbatim
* @param p0 the first point.
* @param p1 the second point.
* @param p2 the third point.
* @param p3 the fourth point.
* @param p4 the fifth point.
* @param p5 the sixth point.
* @param p6 the seventh point.
* @param p7 the height point.
* @return the dart of the new hexahedron incident to p0
* and to the facet (p0,p5,p6,p1).
*/
Dart_handle make_hexahedron(const Point& p0,
const Point& p1,
const Point& p2,
const Point& p3,
const Point& p4,
const Point& p5,
const Point& p6,
const Point& p7)
{
return make_hexahedron(create_vertex_attribute(p0),
create_vertex_attribute(p1),
create_vertex_attribute(p2),
create_vertex_attribute(p3),
create_vertex_attribute(p4),
create_vertex_attribute(p5),
create_vertex_attribute(p6),
create_vertex_attribute(p7));
}
/** Compute the barycenter of a given cell.
* @param adart a dart incident to the cell.
* @param adim the dimension of the cell.
* @return the barycenter of the cell.
*/
template<unsigned int i>
Point barycenter(Dart_const_handle adart) const
{
CGAL_static_assertion(0<i && i<=dimension);
CGAL_assertion(adart != NULL);
// Special case for edge.
if (i==1)
{
Dart_const_handle d2=adart->other_extremity();
if (d2==NULL) return point(adart);
return typename Traits::Construct_midpoint() (point(adart),
point(d2));
}
// General case, 1<i<=dimension
Vector vec(typename Traits::Construct_vector()(CGAL::ORIGIN,
point(adart)));
unsigned int nb = 1;
// TODO: test if we can optimize by using <Self,0,i,i+1> ?
CGAL::CMap_one_dart_per_incident_cell_const_iterator<Self,0,i>
it(*this, adart);
for ( ++it; it.cont(); ++it)
{
vec = typename Traits::Construct_sum_of_vectors()
(vec, typename Traits::Construct_vector()(CGAL::ORIGIN, point(it) ));
++nb;
}
return typename Traits::Construct_translated_point()
(CGAL::ORIGIN, typename Traits::Construct_scaled_vector()(vec, 1.0/nb));
}
/** Insert a point in a given 1-cell.
* @param dh a dart handle to the 1-cell
* @param p the point to insert
* @return a dart handle to the new vertex containing p.
*/
Dart_handle insert_point_in_cell_1(Dart_handle dh, const Point& p)
{
return CGAL::insert_cell_0_in_cell_1(*this, dh,
create_vertex_attribute(p));
}
/** Insert a point in a given 2-cell.
* @param dh a dart handle to the 2-cell
* @param p the point to insert
* @return a dart handle to the new vertex containing p.
*/
Dart_handle insert_point_in_cell_2(Dart_handle dh, const Point& p)
{
Vertex_attribute_handle v = create_vertex_attribute(p);
Dart_handle first = CGAL::insert_cell_0_in_cell_2(*this, dh, v);
if ( first== NULL ) // If the triangulated facet was made of one dart
erase_vertex_attribute(v);
CGAL_assertion( is_valid() );
return first;
}
/** Insert a point in a given i-cell.
* @param dh a dart handle to the i-cell
* @param p the point to insert
* @return a dart handle to the new vertex containing p.
*/
template <unsigned int i>
Dart_handle insert_point_in_cell(Dart_handle dh, const Point& p)
{
CGAL_static_assertion(1<=i && i<=2);
if (i==1) return insert_point_in_cell_1(dh, p);
return insert_point_in_cell_2(dh, p);
}
/** Insert a dangling edge in a given facet.
* @param dh a dart of the facet (!=NULL).
* @param p the coordinates of the new vertex.
* @return a dart of the new edge, incident to the new vertex.
*/
Dart_handle insert_dangling_cell_1_in_cell_2(Dart_handle dh,
const Point& p)
{
return CGAL::insert_dangling_cell_1_in_cell_2
(*this, dh, create_vertex_attribute(p));
}
/** Insert a point in a given i-cell.
* @param dh a dart handle to the i-cell
* @param p the point to insert
* @return a dart handle to the new vertex containing p.
*/
template <unsigned int i>
Dart_handle insert_barycenter_in_cell(Dart_handle dh)
{ return insert_point_in_cell<i>(dh, barycenter<i>(dh)); }
/** Compute the dual of a Linear_cell_complex.
* @param amap the lcc in which we build the dual of this lcc.
* @param adart a dart of the initial lcc, NULL by default.
* @return adart of the dual lcc, the dual of adart if adart!=NULL,
* any dart otherwise.
* As soon as we don't modify this lcc and alcc lcc, we can iterate
* simultaneously through all the darts of the two lcc and we have
* each time of the iteration two "dual" darts.
*/
Dart_handle dual_points_at_barycenter(Self & alcc, Dart_handle adart=NULL)
{
Dart_handle res = Base::dual(alcc, adart);
// Now the lcc alcc is topologically correct, we just need to add
// its geometry to each vertex (the barycenter of the corresponding
// dim-cell in the initial map).
typename Dart_range::iterator it2 = alcc.darts().begin();
for (typename Dart_range::iterator it(this->darts().begin());
it!=this->darts().end(); ++it, ++it2)
{
if (vertex_attribute(it2) == NULL)
{
alcc.set_vertex_attribute(it2, alcc.create_vertex_attribute
(barycenter<dimension>(it)));
}
}
return res;
}
};
} // namespace CGAL
#endif // CGAL_LINEAR_CELL_COMPLEX_H //
// EOF //
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