Questions about nanovdb

[trsh]

1. How do we manage some kind of hierarchy? Lets say I have bunch of voxels in the grid (leaves), at some place, with different color values. And I want for them to have sort of a parent node, that has a color value equal to interpolated between those child voxels. And then I could something similar to ZeroCrossing but with LOD level 2 and hit this parent node and get the color value. Without any need to loop trough all leaves.

2. Is there some technique or ready to use functionality, to retrieve all voxels in a certain area? Like I could define a sphere/box/line/cone, and I could get all voxels inside and/or intersecting. Or its just very simple math and not it's trivial to have special functions for this?