CGAL users discussion list

["Sebastien Loriot (GeometryFactory)" <>]

Currently, the class Point_set_2 inherits from Delaunay_triangulation_2.

The only solution I can propose right now, is to use a TDS with a 
vertex_with_info
(see example Adding colors here:
http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Triangulation_2/Chapter_main.html#Section_35.11
but use as vertex type Vertex_base_with_info_2, see also:
http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Point_set_2_ref/Class_Point_set_2.html)

Then use for example:
Vertex_handle vi=PSet.insert(pi);
vi->info()= i;

A better solution should come up with CGAL 3.9

S.





Battalgazi YILDIRIM wrote:
> Hi,
>
> I am looking following example under 
> examples/Point_set_2/nearest_neighborhood.cpp.  I want to
> assign some values to each points.  After I found nearest points, I 
> would like to reach
> nearest points' values. I can do this through std::map, but I don't feel 
> that it is the
> right way.
>
> As an example, you have temperature field over 2D domain (x,y). Each point
> you have some temperature value  such as (x,y,T).  When I ask nearest
> points around (x0,y0), I also  want to get T values, in addition to 
> (x,y)s , of nearest locations.
>
>
> Could you help me out?
>
> Thanks,
> #include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
> #include <CGAL/Point_set_2.h>
> #include <list>
>
> typedef CGAL::Exact_predicates_inexact_constructions_kernel K;
>
> typedef CGAL::Point_set_2<K>::Edge_iterator  Edge_iterator;
> typedef CGAL::Point_set_2<K>::Vertex_handle  Vertex_handle;
> typedef K::Point_2                           Point_2;
>
> CGAL::Point_set_2<K> PSet;
> Point_2 ar1[5];
>
>
> int main()
> {
>   std::list<Point_2> Lr;
>
>   Point_2 p1(12,14);
>   Point_2 p2(-12,14);
>   Point_2 p3(2,11);
>   Point_2 p4(5,6);
>   Point_2 p5(6.7,3.8);
>   Point_2 p6(11,20);
>   Point_2 p7(-5,6);
>   Point_2 p8(12,0);
>   Point_2 p9(4,31);
>   Point_2 p10(-10,-10);
>
>   Lr.push_back(p1); Lr.push_back(p2); Lr.push_back(p3);
>   Lr.push_back(p4); Lr.push_back(p5); Lr.push_back(p6);
>   Lr.push_back(p7); Lr.push_back(p8); Lr.push_back(p9);
>   Lr.push_back(p10);
>
>   PSet.insert(Lr.begin(),Lr.end());
>
>    // init
>   ar1[0]=p4; ar1[1]=p5; ar1[2]=p3; ar1[3]=p7; ar1[4]=p8;
>
>   Point_2 actual(3.0,4.5);
>
>   // nearest neighbor ...
>   Vertex_handle v = PSet.nearest_neighbor(actual);
>   std::cout << "Nearest neighbor:" << v->point() << "\n";
>
>   // k nearest neighbors ...
>   std::list<Vertex_handle> L;
>   std::list<Vertex_handle>::const_iterator it;
>
>   PSet.nearest_neighbors(actual,7, std::back_inserter(L));
>   std::cout << "actual point: " << actual << "\n";
>
>   for (it=L.begin();it != L.end(); it++)
>       std::cout << (*it)->point() << " infor = " << (*it)->info() << "\n";
>
>   return 0;
> }
>
>
> --
> B. Gazi YILDIRIM