CGAL users discussion list

["Sebastien Loriot (GeometryFactory)" <>]

After fixing compiling errors in your code it was working fine on my
machine with CGAL 3.9 (see the attached code).

Did you have a look at this section where you can attach info to points 
stored in the tree by using property maps?

http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Spatial_searching/Chapter_main.html#Subsection_60.3.6

Sebastien.



 wrote:
> typedef CGAL::Exact_predicates_inexact_constructions_kernel         K;
> typedef K::Point_3 Point3;
>
>         struct Point:public Point3
>         {
>                 Point(double dx,double dy,double dz):Point_3(dx,dy,dz)
>                 {
>
>                         bUsed = false;
>                 }
>                 AcDbObjectId id;
>
>                 bool bUsed;
>         };
>
>         struct Construct_coord_iterator
>         {
> 		// Get an iterator for the approximate coordinates. 
> 		const Point::Cartesian_const_iterator operator() (const Point&
> nnp) const
>                 {
>                         return (nnp.cartesian_begin());
>                 }
>
> 		//Get a past-the-end iterator for the approximate coordinates. 
> 		const Point::Cartesian_const_iterator operator() (const Point&
> nnp, int) const
>                 {
>                         return (nnp.cartesian_end());
>                 }
>         };
>
>         typedef CGAL::Search_traits<K::FT, Point, const
> double*,Construct_coord_iterator> Traits;
>         typedef CGAL::Orthogonal_incremental_neighbor_search<Traits>
> NN_incremental_search;
>         typedef NN_incremental_search::iterator NN_iterator;
>         typedef NN_incremental_search::Tree Tree;
>
>         struct point_not_used{
>                 bool operator()(const NN_iterator& it)
> 		{ 
> 			return (((*it).first).bUsed);
>                         //return true;
>                 }
>         };
>         // An iterator that only enumerates dD points with positive
> x-coordinate
>         typedef CGAL::Filter_iterator<NN_iterator,point_not_used>
> NN_positive_x_iterator;
>
> .... //init a Tree ojbect and do the below seach.
>
> NN_incremental_search NN(tree,query);
>                 NN_positive_x_iterator
> it(NN.end(),point_not_used(),NN.begin()),end(NN.end(),point_not_used());
>                 for (int j=0;(j<nK)&&(it!=end);++j,++it)
>                 {
>                         const Point& p = (*it).first;
>                         Point& pp = const_cast<Point&>(p);
>
>
>                         pp.bUsed = true;// why can this line not change the
> tree's point extra info "bUsed".
>
>                         idArr_Res.append(p.id);
>                         acutPrintf(_T("\nsquard
> distance=%g"),CGAL::to_double((*it).second));
>                 }
>
>    the code above can be compiled well, but "pp.bUsed = true" did nothing, why
> can't change the tree's point extral info.

#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Orthogonal_incremental_neighbor_search.h>
#include <CGAL/Search_traits.h>

typedef CGAL::Exact_predicates_inexact_constructions_kernel	    K;
typedef K::Point_3 Point3;

struct Point:public Point3
{
  Point(){}
  Point(double dx,double dy,double dz):Point3(dx,dy,dz)
  {

    bUsed = false;
  }

  bool bUsed;
};

struct Construct_coord_iterator
{
  typedef Point::Cartesian_const_iterator result_type;
  // Get an iterator for the approximate coordinates. 
  Point::Cartesian_const_iterator operator() (const Point& nnp) const
  {
    return (nnp.cartesian_begin());
  }

  //Get a past-the-end iterator for the approximate coordinates. 
  Point::Cartesian_const_iterator operator() (const Point& nnp, int) const
  {
    return (nnp.cartesian_end());
  }
};

typedef CGAL::Search_traits<K::FT, Point, const double*,Construct_coord_iterator> Traits;
typedef CGAL::Orthogonal_incremental_neighbor_search<Traits> NN_incremental_search;
typedef NN_incremental_search::iterator NN_iterator;
typedef NN_incremental_search::Tree Tree;

struct point_not_used{
  bool operator()(const NN_iterator& it)
  { 
    return (((*it).first).bUsed);
    //return true;
  }
};
// An iterator that only enumerates dD points with positive x-coordinate
typedef CGAL::Filter_iterator<NN_iterator,point_not_used> NN_positive_x_iterator;

int main(){

  Tree tree;

  std::list<Point> lst;
  lst.push_back(Point(0,0,0));
  lst.back().bUsed=true;
  lst.push_back(Point(0,0,1));
  lst.back().bUsed=true;
  lst.push_back(Point(0,1,1));
  lst.push_back(Point(1,1,1));
  lst.push_back(Point(2,1,1));
  lst.push_back(Point(2,2,3));
  lst.push_back(Point(2,2,2));

  tree.insert(lst.begin(),lst.end());
  int nK=2;  
    

  Point query(0,0,0.1);

    
  NN_incremental_search NN(tree,query);

  std::cout << NN.begin()->first.bUsed << std::endl;
  std::cout << (++NN.begin())->first.bUsed << std::endl;

  NN_positive_x_iterator it(NN.end(),point_not_used(),NN.begin()),end(NN.end(),point_not_used());
  for (int j=0;(j<nK)&&(it!=end);++j,++it)
  {
    const Point& p = (*it).first;
    Point& pp = const_cast<Point&>(p);
    pp.bUsed = false;// why can this line not change the tree's point extra info "bUsed".
  }
  std::cout << NN.begin()->first.bUsed << std::endl;
  std::cout << (++NN.begin())->first.bUsed << std::endl;

}