CGAL users discussion list

[Battalgazi YILDIRIM <>]

Hi Sebastian,

I don't know much about Alpha_shape_3, but it seems that it is what I am looking for if I 
set  the alpha parameter is 0. I will have all surface points and I want hull,

But, after that I need to have some kind of connectivity information to get from this concave hull.

I need FaceNodes  and CellNodes connectivity 
(FaceNodes: I have to know a face ID and its connected node IDs, 
CellNodes: Cell ID and its connected node IDs).

Do you help me how to get these information out of Alpha_shapes_3 object?

Thanks,

On Tue, Jan 3, 2012 at 1:15 PM, Sebastien Loriot (GeometryFactory) <> wrote:

One thing you can try is the Alpha_shape_3 demo
(in CGAL_ROOT/demo/Alpha_shape_3) and play with the slider to see
whether the reconstruction fit your needs.


Sebastien.

Battalgazi YILDIRIM wrote:

Hi Sebastian,

Our problem we have a simple shape of beam (thin plate) is deforming,

one of our solver is particle based solver and it send  surface   points of
the beam to other mesh-based solver. The mesh based solver takes these points and needs
to create the surface mesh.  But we insist on the original points, otherwise we have
a lot complications.

Those points might create a concave shape, I think that convex shape is not guaranteed.

Thanks,

On Tue, Jan 3, 2012 at 11:08 AM, Sebastien Loriot (GeometryFactory) < <mailto:>> wrote:

   Do your points have some particular properties (on a convex shape,
   inside a set of planes, ...)?

   Sebastien.

   Battalgazi YILDIRIM wrote:

       Hi Sebastian,

       Thanks for answer,

       Is there any other way to do in CGAL, just give surface points
       and get reconstructed mesh
       connecting those points?

       Thanks,

       On Tue, Jan 3, 2012 at 2:20 AM, Sebastien Loriot
       (GeometryFactory) <

       <mailto:> <mailto:

       <mailto:>>> wrote:

          Battalgazi YILDIRIM wrote:


              Hi,

              I am trying to use points and normals to reconstruct surface
              mesh, I follow "Surface
              Reconstruction from Point Sets" section in CGAL.

              I have some input points and its normal. Since algorithm
       solves
              eliptic equation of
              Poisson reconstruction and it gives a approximate surface.

              Is it possible to reconstruct mesh that its vertices are
               exactly the same with input?


          This is not possible with this algorithm.

          Sebastien.



              if you can help me, I would be really glad,

              Thanks,



              B. Gazi YILDIRIM



          --     You are currently subscribed to cgal-discuss.
          To unsubscribe or access the archives, go to

          https://lists-sop.inria.fr/____wws/info/cgal-discuss
       <https://lists-sop.inria.fr/__wws/info/cgal-discuss>

          <https://lists-sop.inria.fr/__wws/info/cgal-discuss
       <https://lists-sop.inria.fr/wws/info/cgal-discuss>>




       --         B. Gazi YILDIRIM



   --     You are currently subscribed to cgal-discuss.
   To unsubscribe or access the archives, go to
   https://lists-sop.inria.fr/__wws/info/cgal-discuss
   <https://lists-sop.inria.fr/wws/info/cgal-discuss>




--
B. Gazi YILDIRIM

--
You are currently subscribed to cgal-discuss.
To unsubscribe or access the archives, go to
https://lists-sop.inria.fr/wws/info/cgal-discuss

-- 
B. Gazi YILDIRIM