OpenVDB vector grid padding

[Elyg]

Hello,

In our render engine for mb we need to make sure that the vel VDBs have the their active region padded, essentially streaking the vel field by itself and activating all the voxels along the way keeping the vel value in those new voxels

So taking the voxel, query the vector, and activate everything along its path

e.g.

single voxel with v (velocity vector)
v = (2,0,0)

original vel grid
--------
|    v | 
-------- 

new vel grid with padding
--------  -------  --------
|   v  |    v    |  v     |
-------- --------  --------

At the moment to achieve this I am converting everything into a point cloud and afterwards rebuilding the vdb grid (in houdini), which can be very heavy computationally and memory intensive for big grids.
Are there any tools in the openvdb toolkit/library that would help me activate the voxels and regions without needing to go from vdb -> points -> vdb and do it directly on the grid itself?

I am looking to hopefully discover something that will help do it from the get got, or otherwise some pointers where would be best to start on writing a custom plugin to achieve it

Thanks in advance