[Paraview] vtkHyperOctree

[Jean M. Favre]

Folks

I am evaluating the possibilities of using the HyperOctree to support an
astro-physics code. First question: Can we set a threshold to switch the
GeometryFilter to a bounding box mode when loading an hyperoctree? By
default the surface-mode is always ON and for an octree beyond 8 levels
of refinement, things are getting heavy.

Second question: I don't see what method should be used for
parallelizing the construction of the octree. Could one use  tags such a
mixture of UPDATE_RESOLUTION and UPDATE_PIECE_NUMBER  to divide up the
load? Are filters downstream ready to propagate the meta-data requests
for octrees? The example of the HyperOctree Fractal does a depth-first
construction. I suppose breadth-first is also possible since the
HyperOctreeCursor enables navigation in both direction. Simulation codes
actually use space-filling curves (e.g. Hilbert curves or others) and in
terms of reading back the data, this could one efficient way to access
data from disk, where each server follows a segment of the Hilbert
curve.  I just don't know if anyone has ever done parallel octree builds
in ParaView and if this is feasible?

--
Jean
Swiss National Supercomputing Center