Numerics of "Gradient Of Unstructured DataSet" Filter

I’ve been working on getting the structured grid and applying the Gradient filter once my Resample To Image is generated. However, I’m having issues getting Gradient to work. When I import my CFD results, I have:

  • Point Data: contains point 3D space orientation, velocity vector, velocity-component array(s) [x, y, z]
  • Cell Data: Block Number, Cell ID, Cell Type (Tetrahedron)

I can create the structured grid, and the vectors/scalars are transferred over well. I’m able to visualize nicely with the “Volume” rendering. I use Transform to scale the data back to the correct scale (m → mm) before creating the structured grid. I am able to apply Gradient to either version of the structured grid, but I’m having errors.

For the case where I’ve transformed > grid generation, I get:

No Scalar Field has been specified - assuming 1 component!

Which is strange, because I am feeding it a scalar. When applying to the NON-transformed grid, I don’t receive any errors. However, the bounds of the gradient-dataset are stretched/do not stay at the same location or scale. The top two images show the structured grid/shape of my volume render. The bottom two show how Gradient caused a massive expansion.