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Re: [cgal-discuss] Faulty vertex normal transforming Polyhedron -> Nef Polyheron.


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  • From: "Sebastien Loriot (GeometryFactory)" <>
  • To:
  • Subject: Re: [cgal-discuss] Faulty vertex normal transforming Polyhedron -> Nef Polyheron.
  • Date: Fri, 20 Nov 2015 08:42:53 +0100
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  • Organization: GeometryFactory

The nef facets are triangulated using a projection of the vertices inside the XY, YZ or ZX plane followed by a call to Delaunay
on the projected plane.

One thing to try is to hack the class Build_polyhedron
define in Nef_polyhedron_3.h:762 and remove the if part
line 793 to keep only the else. That way your polyhedron
faces won't be triangulated.

Then you can call triangulate_faces [1]

If this gives good results, we will thing about doing this by
default.

Sebastien.

[1] http://doc.cgal.org/latest/Polygon_mesh_processing/group__PkgPolygonMeshProcessing.html#ga78da163452ce0675288191bcab1dedc8

On 11/18/2015 11:08 AM, Gilles wrote:
Hello,

May be a newbie question !

To be able to achieve boolean operations, I have to transform *Polyhedron
into Nef Polyhedron* and from Nef Polyhedron once the boolean operation is
done.

The problem :

The way the transformation triangulate makes *faulty normals *(please look
at the image).

Is there a way to triangulate "properly" the polyhedron to avoid this
problem.

Thank you in advance
Best Regards.

Gilles


<http://cgal-discuss.949826.n4.nabble.com/file/n4661349/normals.png>




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