dolfin team mailing list archive

[Shawn Walker <walker@xxxxxxxxxxxxxxx>]

Hello all.

I have finally got some time to put in (at least the first stage) the 
higher order mesh stuff for triangles
mapped with P2 lagrange elements. Just to remind you, the agreement that 
we came up with was this:

1. The local mapping for each element is independent of whatever finite 
elements you are using.  Thus, there
should be a completely different description of the mapping.

2. This info will be stored in MeshGeometry with extra data structures.

3. The info to store is (i) all the higher order vertex position data, and 
(ii) the `DoFmap' for your
particular map.  Storing the extra vertex data is just like storing the 
usual 3 triangle coordinates.

4. Eventually, for computing the local finite element matrices, there just 
needs to be a short subroutine
that returns the higher order vertex data (for a specific cell) to be used 
by, say, the code generated by
FFC.

My question is about the dofmap.  It is certainly reasonable to store it 
similarly to the vertex data.  But
there is a problem if the mesh is locally refined.  It seems like it will 
be a pain to modify this data
structure.  Any suggestions for this?

Remember, we do NOT want to use a function space here.  This was already 
discussed!

- Shawn