shards Version of the Day
node = J < node_count ? IndexListAt< node_map,
polarity = IndexListAt< PermutationPolarity,
Node permutations for proper subcells.
ParentCell and SubCell are connected if every node of SubCell is also a node of ParentCell. However, the connection may be permuted.
Let ParentCell be dimension D and SubCell be dimension dim < D. Let SubCell be connected as subcell Ord with permutation P.
Then ParentCell.node(K) == SubCell.node(J) where:
The permutation map for P == 0 is required to be identity.