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[Damian Sheehy <>]

Are you kidding?

Why don't you do this . . . . 

          Point vertex = triangle.vertex(2);

           triangles.push_back(Vec3(vertex.x(), vertex.y(), vertex.z()));
>         vertex = triangle.vertex(1);
>         triangles.push_back(Vec3(vertex.x(), vertex.y(), vertex.z()));
>
>         vertex = triangle.vertex(0);
>         triangles.push_back(Vec3(vertex.x(), vertex.y(), vertex.z()));


Instead of this. . . . .

          Point vertex = triangle.vertex(0);
           triangles.push_back(Vec3(vertex.x(), vertex.y(), vertex.z()));
>         vertex = triangle.vertex(1);
>         triangles.push_back(Vec3(vertex.x(), vertex.y(), vertex.z()));
>
>         vertex = triangle.vertex(2);
>         triangles.push_back(Vec3(vertex.x(), vertex.y(), vertex.z()));

 

Damian

On Thu, Jul 16, 2009 at 1:19 PM, <> wrote:

Hello, Im trying to use CGAL to triangulate polygon and I run into problem with
triangle orientation. CGAL always generate counter clock wise triangles for
some polygons. Here is my code:

typedef CGAL::Exact_predicates_inexact_constructions_kernel K;


   typedef CGAL::Triangulation_3<K> Triangulation;

   typedef Triangulation::Cell_handle Cell_handle;
   typedef Triangulation::Vertex_handle Vertex_handle;
   typedef Triangulation::Locate_type Locate_type;
   typedef Triangulation::Point Point;
   typedef Triangulation::Facet_iterator Facet_iterator;
   typedef Triangulation::Facet Facet;

   // construction from a list of points :

   std::list<Point> L;

       L.push_back(Point(0, 0, 0));
       Lpush_back(Point(25, 0, 0));
       Lpush_back(Point(25, 0, 25));
       Lpush_back(Point(0,0, 25));


   Triangulation T(L.begin(), L.end());

   for (Triangulation::Finite_facets_iterator fit = T.finite_facets_begin();
fit != T.finite_facets_end(); ++fit)
   {
       K::Triangle_3 triangle = T.triangle(*fit);
       Point vertex = triangle.vertex(0);
       triangles.push_back(Vec3(vertex.x(), vertex.y(), vertex.z()));

       vertex = triangle.vertex(1);
       triangles.push_back(Vec3(vertex.x(), vertex.y(), vertex.z()));

       vertex = triangle.vertex(2);
       triangles.push_back(Vec3(vertex.x(), vertex.y(), vertex.z()));
   }

can I somehow set Triangluation to give me clockwise triangles? thx for help
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