[Dune] Intersection area and corners

[Marco Cisternino]

Good morning,
I have a problem with one intersection in my dune application.
The area I get is not what I expect.
So I tried to look inside the Intersection object using gdb
It is important to say that my grid is a GeometryGrid with a DiscreteFunction to parametrize the elements.

If I look at these two things:

- *(in.real.insideGeo_.mapping_)
- *(iGeo.realGeometry.mapping_)

where the in variable type is 
GeometryGrid::LeafGridView::IntersectionIterator::Intersection
and iGeo is 
GeometryGrid::LeafGridView::IntersectionIterator::Intersection::Geometry

I see different corners stored in. I mean two of the 4 corners given by *(iGeo.realGeometry.mapping_) are different from the two correspondant corners given by *(in.real.insideGeo_.mapping_). All the other corners are the same.

If I compute the intersection area using corners given by *(in.real.insideGeo_.mapping_), I get the right area. On the other hand, if I compute the intersection area using the corners given by *(iGeo.realGeometry.mapping_), the area is wrong.

I want to specify that the corners given by *(in.real.insideGeo_.mapping_) are the same I get using e.geometry().corners(i) where e is of type
GeometryGrid::LeafGridView::template Codim<0>::template Partition<Dune::InteriorBorder_Partition>::Iterator::Entity

Could anyone help me please? Am I doing something wrong?
Ask for more details if you need.

I'm using DUNE 2.3 with ALUGrid 1.52. I know it is old, but at the moment I cannot migrate to the new Dune releases.

Thanks a lot!

Marco