A gridformat-compatible grid type for CVFE discretizations that uses DuMux DOF indices directly for VTK point field lookup. More...

#include <config.h>

Description

Unlike gridformat's LagrangePolynomialGrid this class uses the DuMux dofMapper to identify DOFs, making writing higher-order point fields from a DOF-indexed solution vector efficient (no FE evaluation):

IO::GridWriter writer{IO::Format::vtu, gridView, IO::order<2>};
writer.setPointField("velocity", x);   // x indexed by order-2 Lagrange DOF index
writer.write("output");

Parallel correctness: internally the grid builds a sequential VTK point index (0…N_used-1) that covers only DOFs referenced by interior-partition cells, filtering out ghost/overlap DOFs not owned by this process. Each Point object carries both the sequential VTK index (used by gridformat for connectivity) and the DuMux DOF index (used for solution lookup).

The VTK Lagrange connectivity inside each element is built using the same dune_to_gfmt_sub_entity ordering as gridformat, so the output is valid VTK Lagrange XML. For methods with multiple DOFs per edge/face (PQ3 and higher), the geometry helper's orientation-consistent dofIndex is used to ensure shared-entity DOFs get the same global index from all elements.