This node splits level set VDB volume primitives into multiple fragments.
To fracture the VDB primitives, you must supply some cutter geometry in the second input. The optional third input specifies points onto which the cutter geometry will be instanced (or transformed onto) to perform the cutting.
Typically, the first input is the result from a VDB from Polygons node. The fractured result can then be converted back to polygons seamlessly by using the Convert VDB node with the original polygons as the second input.
The cutter geometry must be a closed surface but does not need to be manifold. The cutter geometry can contain self intersections and degenerate faces. Normals on the cutter geometry are ignored.
The reference points supplied in the optional third input can have attributes that control how the cutter is transformed onto them. This follows the same rules as what the Copy node does, except for scaling. Scaling SDFs correctly require that the level set be rebuilt at the same time. Thus you must scale your cutter geometry appropriately first.
The name(s) of the VDB primitives to fracture. See specifying volumes.
Separate Cutters by Connectivity
The cutter geometry will be classified by point connectivity. Each connected component will be cut separately. Use this if an individual piece of cutting eometry has overlapping components.
Allow Cutter Overlap
Allow consecutive cutter instances to fracture previously generated fragments.
Center Cutter Geometry
If enabled, the cutter geometry will be first centered around its point position centroid.
Randomize Cutter Rotation
Apply a random rotation to each cutter as it is instanced onto each point.
Seed value for randomize cutter rotation.
Split Input Fragments into Primitives
Split input VDBs with disjoint fragments into multiple primitives, one per fragment.
If you have a tube and cut out the middle, the two ends might end up in the same VDB. This option will detect that and split the ends into two VDBs.
This operation only needs to be performed if you plan on using the output fragments for collision detection. If you use multiple fracture nodes, then it is most efficient to only enable it on the very last fracture node.
Specifies the group name to associate all fragments generated by this fracture. The residual fragments of the input VDBs are excluded from this group.
The generated VDBs can be coloured uniquely to make it easy to see the new pieces. The New Fragments option will leave the original pieces with their original colouring, only affecting the net-new pieces.