[Dune] Feature request

[Christian Engwer]

Hi,

I'm using DG myself I never got hte problems you described. The
integral over the intersection I do as follows:
1) I have intersection iterator.
2) the quadrature points are defined in local coordinates of the
   intersection's reference element, i.e. a line in 2D or a triangle
   or quadrilateral in 3D.
3) using intersectionSelfLocal and intersectionNeighborLocal I can
   map the quadrature points onto the element's or the neighbor's
   reference element.
4) I evalute the function in local coordinates of the element.

Perhaps I missed something, but where do you need the twist?
There is one thing that can be important... if you assemble one part
from the element and an other part from the neighbor then you get into
trouble if you use a non-symetric quadrature rule or you need to know
the orientation of the intersection. But this problem should not
occure as the quadrature rules in Dune are all symetric at the moment.

Christian