Old development ideas

[tkeskita]

Moved old development ideas here from readme:

• Don't save Unstructured Grid object in blend file to save disk space
  (mesh is anyways thrown away and regenerated from UG text
  strings)

• Add Gzip option to OpenFOAM PolyMesh export

• Split Cells (Edge Division) (e.g. hexahedral cell is split to 8
  cells, tetrahedral cell is split into 4 cells)

• Dissolve Internal Faces (merge cells)

• Merge Overlapping Boundary Faces (e.g. to merge two mesh regions)

• Separate Internal Faces (convert internal face to two boundary faces)

• Split Cells (Center Slicing) (polyhedron cell face vertices are
  connected to cell center)

• Show Cells (creates temporary object with faces around
  selected cells)

• Fix Intersecting Boundaries (move boundary vertices so
  that boundary faces don't intersect each other)

• Support for OpenFOAM sets?

• Mesh Quality metrics + operator to select bad cells. Definition of
  bad cells depend on target simulation type, so there would need to
  be several metrics. This would be nice-to-have but not essential,
  since it is possible to use checkMesh utility of OpenFOAM, or
  e.g. Mesh Quality filter in Paraview or e.g.
  BVTKNodes
  to evaluate mesh quality.