Add Map Node apply levelset data from texture map through Map Helper node to the VDB Grid.
White get no effect. Black get shrink.

Input / VDB Grid:
Input vdb data for Add Map. You must connect this input for create.

Input / Map Helper:
Input map helper object for Add Map.
And select map type “2D map” or “3D map”. For 2D map, you need to have UVW channel on input grid.
You must connect this input for create.

Output / VDB Grid:
output result vdb data.

Multiplier:
Defines amount of the effect.