[Dune] Are there hanging nodes in Alugrid

[Aleksejs Fomins]

Dear Dune,

We plan to implement adaptive tetrahedron refinement for our 
electromagnetic solver (HADES3D).
We currently use alugrid-1.22 and the question is as follows:

If we have a large tetrahedral mesh and we decide to refine 1 
tetrahedron in its middle,
will alugrid refine only that element creating hanging nodes or do 
something else?

Kind regards,
Aleksejs Fomins

Paul Scherrer Institut