Houdini 19.0 Nodes Geometry nodes VDB Analysis

VDB Analysis geometry node

Computes an analytic property of a VDB volumes, such as gradient or curvature.

Since 12.5

See volumes for an explanation of standard volumes and OpenVDB volumes.

This node computes some property from the values of VDB volumes, and generates new VDB volumes where the voxel values are the computed results. Using the Output name parameter you can choose whether the results volumes replace the original volumes.

Parameters

Group

The name(s) of the VDB primitives to analyze. See specifying volumes.

Operator

What to compute. The labels on the items in the menu indicate what datatype the incoming VDB volume must be and the datatype of the output volume.

Gradient (scalar → vector)

The gradient of a scalar field.

Curvature (scalar → scalar)

Mean curvature of a scalar field.

Laplacian (scalar → scalar)

The Laplacian of a scalar field.

Closest Point (scalar → vector)

Generates voxels containing the location of the closest point on a surface defined by the incoming signed distance field.

You can then use the resulting field with the VDB advect points node to stick points to the surface.

Divergence (vector → scalar)

The divergence of a vector field.

Curl (vector → vector)

The curl of a vector field.

Magnitude (vector → scalar)

The length of the vectors in a vector field.

Normalize (vector → vector)

Divides vector field’s values by their lengths.

Mask VDB

VDB (from the second input) used to define the iteration space.

Output Name

How to name the generated VDB volumes. If you choose “Keep incoming names”, the generated fields will replace the input fields.

Custom Name

If this is not blank, the output VDB will use this name.

See also

VDB Analysis