Houdini 20.0 Nodes Geometry nodes

Volume Break geometry node

Cuts polygonal objects using a signed distance field volume.

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Since 10.0

The Volume Break operation cuts polygonal objects using a signed distance field (SDF). An SDF is a function over space, which evaluates to the signed distance to the surface of a specified volume.

It can be specified whether to keep the portion of the cut geometry lying inside or outside the volume, or keep all the geometry. Additional geometry may also be generated to close any holes created by the cut.

Note

This node currently only works with standard Houdini volumes. It does not work with VDBs.

Parameters

Geometry to Keep

Retain the geometry inside or outside the SDF volume, or all.

Closing Geometry

Add geometry to fill in holes created by the cut, or leave them open (do not close).

  • Flat: create one polygon for each hole (may not be planar).

  • Pyramid: find an apex point so that the closing geometry is a pointy approximation to the volume.

Close Polygons

If holes are left open, then check this option to close polygons that were opened by the cut. If holes are closed, then polygons are automatically closed.

Snapping Tolerance

A high tolerance will cause cuts to occur from vertex to vertex, while a low tolerance will cause the geometry to be split more accurately by introducing new vertices. To avoid tiny polygons, set the tolerance above zero.

Create Groups

Create groups to tell between the output geometry lying inside and outside the volume.

Inside Group

Primitive group containing polygons inside the volume.

Closure

Primitive group containing the closing geometry with respect to the inside geometry.

Outside Group

Primitive group containing polygons outside the volume.

Closure

Primitive group containing the closing geometry with respect to the outside geometry. The contents are identical to that of the first closure group.

Inputs

Geometry

The polygonal geometry to be cut.

Volume

The SDF volume used to cut the geometry.

See also

Geometry nodes