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[Josip Dzolonga <>]

It might be that the answer is obvious, but since I have very limited experience with CGAL I can not see a direct way of doing this. The following does not work by the same reasons I suspect

std::list<Vertex_handle> toRemove;

for(std::list<Facet>::iterator iter = grown->facets->begin();

      iter != grown->facets->end(); ++iter) {     

    Cell_handle c = (*iter).first;

int index = (*iter).second;

toRemove.push_back(c->vertex((index+1)%4));

toRemove.push_back(c->vertex((index+2)%4));

toRemove.push_back(c->vertex((index+3)%4));

}

T.remove(toRemove.begin(), toRemove.end());

Thanks,

Josip

On Fri, Nov 6, 2009 at 4:21 PM, Sylvain Pion <> wrote:

Josip Dzolonga wrote:

Here is the problematic code:

for(std::list<Facet>::iterator iter = grown->facets->begin();
     iter != grown->facets->end(); ++iter) {
   Cell_handle c = (*iter).first;

int index = (*iter).second;
T.remove(c->vertex((index+1)%4));
T.remove(c->vertex((index+2)%4));
T.remove(c->vertex((index+3)%4));
}

Basically, I have a set of facets that I have extracted from the triangulation and I want to remove them along with their points. But, the T.remove lines cause segmentation faults, where T is of type CGAL::Triangulation_hierarchy_3<Dt>. I get no precondition errors, just a segfault.

When you remove() the first vertex, then the Cell c becomes invalid.
Then, everything can happen.  You need to memorize the Vertex_handles
first, and then remove them without refering to Cells or Facets that
may become invalid.

--
Sylvain Pion
INRIA Sophia-Antipolis
Geometrica Project-Team
CGAL, http://cgal.org/

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