Faulty generation of Ghosts for vtu file formats
Hi all,
I use Paraview 5.10.1 and openMPI 4.0.3. There seems to be a problem with the generation of ghost cells for vtu files, more precisely some ghost points are not flagged as ghosts. Here is a pipeline to reproduce the problem:
To do the distribution of the vtu data, I first execute the following pipeline using the builtin pvserver:
Wavelet > GenerateGlobalIds > RedistributeDataSet
Le Whole Extent of the Wavelet is between -2 and 2 insterad of the default values -10 and 10 (for x, y, and z). The RedistributeDataSet has the option “Preserve Partition In Output” checked, and the numboer of partitions is 8. Otherwise, all options are at their default values.
I save the data as a .vtpd file distributed_volume_vtu.zip (11.0 KB), that links to several vtu files (as it should). Now, I execute Paraview using another server, executed with mpirun:
mpirun -n 8 pvserver
I then open the vtpd file, and execute the following Pipeline on it:
Tetrahedralize > ProcessIdScalars > GhostCellsGenerator > GroupDatasets
The ProcessIdScalars has the option Cell Scalars checked, and the GroupDatasets produces a vtkPartitionedDataSetCollection.
Now, when I look at the data in the spreadsheet view, at the level of the GroupDataset,
For the point of Global Id 14, it appears twice in the spreadsheet, as it appears on two processes: one is a ghost point, the other isn’t, as it should as explained here.
For the point of Global Id 22, it appears twice in the spreadsheet, as it appears on two processes: however, neither are ghost points, they both appear as if they truly belong to their processes. This shouldn't be happening, one of the occurrences of the point should be flagged as a ghost.
The screenshot below highlights the two points used here as well as shows their value in the spreadsheet.