Houdini 20.0 Nodes Geometry nodes

VDB to Spheres geometry node

Fills a VDB volume with adaptively-sized spheres.

Since 13.0

This node is useful for generating proxy geometry for RBD simulations since converting non convex polygons into sphere compounds drastically improves the simulation time. This can be used for example, on the output of a VDB Fracture.

It is also useful for cloud modeling, to produce the initial density volume.



The name(s) of VDB primitives to fill. See specifying volumes for more information.


The crossing point of the VDB values that is considered the surface. A value of 0 works for signed distance fields, and 0.5 is a better choice for fog VDBs.

Min Radius in Voxels

Determines the smallest sphere size in voxel units.

Max Radius in Voxels

Determines the largest sphere size in voxel units.

Max Spheres

No more than this number of spheres are generated per VDB primitive.

Scatter Points

Maximum number of interior points to consider for the sphere placement. Increasing this count increases the chances of finding optimal sphere sizes.


When enabled, spheres will be allowed to overlap/intersect.

Preserve Attributes and Groups

Enable to copy attributes and groups from the input.

Add ID Attribute

Enable to add an id point attribute that corresponds to different VDBs.

See also

Geometry nodes