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["Sebastien Loriot (GeometryFactory)" <>]

You can try boundary_to_off()
http://doc.cgal.org/latest/Mesh_3/classCGAL_1_1Mesh__complex__3__in__triangulation__3.html#af1d55be1242c37384224de9b235057cd

Sebastien


On 01/19/2017 04:44 PM, gori23 wrote:
> Hi all,
>
> I solved above problem with loading the Image_3 data
>
> The trick was changing the size parameter in createImage to 2 bytes
> _image* image11 = _createImage(dim, dim, dim, 1, 1.f, 1.f, 1.f, 2, WK_FIXED,
> SGN_UNSIGNED);
>
> I now sucessfully generated tetrahedral meshes with different domains. I am
> struggling with extracting just the surface triangles of the domains
>
> this is briefly what I am doing right now after generating the mesh:
>
>     for (Complex_Cell_Iterator it = c3t3.cells_in_complex_begin(); it !=
> c3t3.cells_in_complex_end(); ++it)
>     {
>
>       const Tr::Cell c(*it);
>       const C3t3::Vertex_handle i1 = c.vertex(0);
>       const C3t3::Vertex_handle i2 = c.vertex(1);
>       const C3t3::Vertex_handle i3 = c.vertex(2);
>       const C3t3::Vertex_handle i4 = c.vertex(3);
>
>      //v1-4 are 3d points with the coordinates of the vertices i1-4
>      // addTri adds an opriented triangle to my mesh structure
>
>       if(c.is_facet_on_surface(f4.second)) addTri(v1, v2, v3);
>       if(c.is_facet_on_surface(f3.second)) addTri(v1, v2, v4);
>       if(c.is_facet_on_surface(f1.second)) addTri(v4, v2, v3);
>       if(c.is_facet_on_surface(f2.second)) addTri(v1, v4, v3);
> }
>
> now when I run above code without the if(c.is_facet_on_surface) conditions
> (and simply add all triangles) I get the tetrahedras, already nicely
> oriented. I had assumed by just getting the surface it also would be
> oriented, but it isn't like that, the orientations seem to be random.
>
> Is there a better way to extract the surface mesh in a oriented way?
>
> Cheers,
>
>
>
>
> --
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> http://cgal-discuss.949826.n4.nabble.com/CGAL-Problem-when-generating-mesh-make-mesh-3-from-segmented-3d-image-tp4661387p4662475.html
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