Specifying geometry mapping

[Martin Sandve Alnæs]

We need some way to specificy higher order geometry mappings of cells.

One alternative is to use named basis function mapping:

• mapping = "affine"
• mapping = "isoparametric"
• mapping = "Piola" (how to handle covariant/contravariant/symmetric Piola here?)

But this is very restrictive, and a more generic approach is preferable. The hard part is not UFL, so consider this design in concert with DOLFIN/UFC/FFC.

[Martin Sandve Alnæs]

Not a well posed issue.