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[Nader SALMAN <>]

A correction , here you go :

// kernel
typedef CGAL::Exact_predicates_inexact_constructions_kernel Kernel;

// Simple geometric types
typedef Kernel::FT FT;
typedef Kernel::Point_3 Point;
typedef Kernel::Vector_3 Vector;

// Point with normal vector stored in a std::pair.
typedef std::pair<Point, Vector> PointVectorPair;
typedef std::vector<PointVectorPair> PointList;

PointList points // Type of input point set

// simplification by clustering using erase-remove idiom
double cell_size = 0.001;

PointList::iterator unwanted_points_begin = CGAL::grid_simplify_point_set(points.begin(), points.end(), CGAL::First_of_pair_property_map<PointVectorPair>(), cell_size);

// delete unwanted points
points.erase(unwanted_points_begin , points.end());

// Optional: after erase(), use Scott Meyer's "swap trick" to trim excess capacity
PointList(points).swap(points);

Sorry for the earlier message,

Cheers,
Nad.

Nader SALMAN

Nader SALMAN a écrit :

Hi Tina,

thank you for your interest in CGAl and for using the PSP package.

here is how you should do it in general :

// kernel
typedef CGAL::Exact_predicates_inexact_constructions_kernel Kernel;

// Simple geometric types
typedef Kernel::FT FT;
typedef Kernel::Point_3 Point;
typedef Kernel::Vector_3 Vector;

// Point with normal vector stored in a std::pair.
typedef std::pair<Point, Vector> PointVectorPair;
typedef std::vector<PointVectorPair> PointList;

CGAL::grid_simplify_point_set(points.begin(), points.end(),
                                               CGAL::First_of_pair_property_map<PointVectorPair>(),
                                               cell_size);


in your case it would be :

 // simplification by clustering using erase-remove idiom
  double cell_size = 0.001;

  points.erase(CGAL::grid_simplify_point_set(points.begin(), points.end(),                                CGAL::First_of_pair_property_map<PointVectorPair>(), cell_size), points.end());

  // Optional: after erase(), use Scott Meyer's "swap trick" to trim excess capacity
  std::vector<Point>(points).swap(points);

Hope this helped!

Cheers,
Nad.

Nader SALMAN
Geometrica Lab, Byron Y308
INRIA Sophia Antipolis (FRANCE)

Tel: +33(0)4 9238 7161   Fax: +33(0)4 9715 5395   


http://www-sop.inria.fr/members/Nader.Salman

tina rumi a écrit :

Hi all,

I am trying to use following function:

points.erase(CGAL::grid_simplify_point_set(points.begin(), points.end(), cell_size),
               points.end());



the type that I am using for points is :

// types
typedef CGAL::Exact_predicates_inexact_constructions_kernel Kernel;
typedef Kernel::Point_3 Point;
typedef Kernel::Vector_3 Vector;

// Point with normal vector stored in a std::pair.
typedef std::pair<Point, Vector> PointVectorPair;

std::list<PointVectorPair> points;

but it caused error. I want to keep this type for points. Do you have any suggestion to fix it.

Thank you,
Tina