Dear PETSc Team,
We are using DMPlex, and we create a mesh using
DMPlexCreateBoxMesh (.... );
and get a uniform mesh. The mesh is periodic.
We typically want to "scale" the coordinates (vertices) of the mesh, and
to achieve this, we call
DMGetCoordinatesLocal(dm, &coordinates);
and scale the entries in the Vector coordinates appropriately.
and then
DMSetCoordinatesLocal(dm, coordinates);
After this, we localise the coordinates by calling
DMLocalizeCoordinates(dm);
This worked fine up to PETSc 3.18, but with versions after this, the
coordinates we get from the call
DMPlexGetCellCoordinates(dm, CellID, &isDG, &CoordSize,
&ArrayCoordinates, &Coordinates);
are no longer correct if the mesh is periodic. A number of the
coordinates returned from calling DMPlexGetCellCoordinates are wrong.
I think, this is because DMLocalizeCoordinates is now automatically
called within the routine DMPlexCreateBoxMesh.
So, my question is: How should we scale the coordinates from a periodic
DMPlex mesh so that they are reflected correctly when calling both
DMGetCoordinatesLocal and DMPlexGetCellCoordinates, with PETSc versions
>= 3.18?
Many thanks, Berend.
