Random Attributes filter does not produce consistent results in some cases
The Random Attributes
does not produce the same result (with the same seed).
Steps to reproduce:
- Create two
Sphere
sources - Apply
Random Attributes
filter on each sphere
Example by coloring by RandomCellVectors
magnitude:
The reason is that the filter internally uses vtkMath::Random()
static function and should use vtkMinimalStandardRandomSequence
.
Another issue is the fact that the filter is not parallel aware and generates different results depending on the number of ranks (each ranks generates the same values).
On the left, the result with 2 ranks, on the right, the result with 4 ranks.
This issue would necessitate to rewrite the filter in order to be parallel aware (for example using GlobalIds
to generate the random values).
These issues can be problematic for regression testing in particular.