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[Ramin H <>]

Thanks for responding Stephane. 

You are right. When refining Facets I always get 0 but when refining cells I get a number larger than 0.

My goal is to apply a certain criterion to a Facet (on the boundary of domain). The criterion depends on calculating the normal vector of the facet. The normal vector must point outward from the domain surface. The direction of this vector is the problem. No matter what method I use, I can not get the coherent direction for all normal vectors of the domain surface (each normal points in a random direction).


I asked about this on the forum before (http://cgal-discuss.949826.n4.nabble.com/normal-vector-of-a-facet-td1580004.html). After applying those recommendations, the directions of normal vectors are still random. 

In do_is_bad(const Facet &f), I thought "f.first" is probably pointing to a cell that is not in the domain for some facets and for others it's pointing to cells that are in the domain. I thought I will check for this fact and use the mirror cell if the cell is not inside the domain. But now that subdomain_index is always zero, I don't know what to do.


I really need to figure this out. Hope you can help me resolve this problem.

Thanks,
-Ramin

On Wed, Apr 28, 2010 at 12:23 PM, Stephane Tayeb <> wrote:

Ramin H wrote:

Hi,

In /Mesh_3/mesh_standard_facet_criteria.h,
in class Uniform_size_ceriterion,
in do_is_bad(const Facet &f):

I am monitoring  subdomain_index of the cell containing f like this:
std::cerr << (int)(f.first->subdomain_index()) << std::endl;

It is always returning 0 for the subdomain index.
Should it not return a number greater than 0 for at least some of the cells?

(My domain is a polyheral domain with only one subdomain.)

-Ramin

Hi Ramin,

If you didn't find an answer by yourself, you may be interested by the following.

If the 3D mesher refines only the surface, it should return 0 (because in this case the mesher updates the status of newly created triangles before updating the status of newly created tetrahedra).

If the 3D mesher is also refines the volume, then it could return something different than 0.

Please let me know in which case you are, and don't hesitate to provide more details about your concern.

NB: I just tried to run the example Mesh_3/mesh_implicit_sphere with the same monitoring as you, and I saw lots of '1'.

Best,
--
Stephane Tayeb
Software engineer - INRIA Sophia Antipolis
Geometrica Project-Team

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