Houdini 13.0 Nodes

Version 0.0.2

Creates the per-primitive piece ID attribute for geometry pieces (PrimGroup family SOP).

Takes an input geometry with primitive ('piece') groups, assigns an unique ID for each group, then creates a per-primitive attribute that stores this ID for all primitives.

This SOP creates the same __origpt attribute that is created by the Voronoi Fracture node, for other SOPs (such as the 'Xform by Points qL') might require this attribute.

In general, it is useful in any case where geometry is fractured/partitioned in some other way than with the Voronoi Fracture SOP, but a compatible geometry setup is expected (e.g. the Assemble SOP doesn’t generate this attribute).

This node is usually used together with other PrimGroup family SOPs – for example, it can read the group ID attributes from the PrimGroup Centroids qL SOP, and the results can be passed to the Xform by Points qL SOP.

Parameters

Mode

Mode for detecting each geometry fracture (by primitive groups or name attribute).

Group Mask

Primitive groups matching this mask will be used for geometry pieces.

Attrib Name

Name of the attribute used to determine the geometry pieces.

Tolerance

A tolerance value name attribute values (in case it contains numerical values, e.g. fracture indices). Values that differ less than the tolerance are considered equal.

Group ID Attribute

Name of the attribute to create. The default name is __origpt (to emulate the output of the Voronoi Fracture SOP).

Group IDs from

The way of determining the index number of each piece group.

Group List Order

Index numbers are assigned incrementally for each piece group in the order they are considered.

Stored Detail Attributes

Use a previously stored detail attribute list for determining indices for the piece groups. The geometry with these attributes is to be connected to the second input (if not, they will be looked for in the first input).

The attributes are expected in a way where the attribute name is the same as the group name, and the attribute value specifies the index number (integer). (For more details of these attributes, see the 'PrimGroup Centroids qL' SOP help.)

Detail Attribs (Unchecked)

Same as the previous mode but with disabled error checking for missing groups and/or attributes. It might be slightly faster for a very large number of pieces.

Note

An __origpt index (or ID) of -1 means that the source group could not be determined for a particular primitive. (It usually means some improper parameter settings).

Delete Groups

No not retain the piece groups once the ID attributes are created.

Delete Detail Attributes

If the group ID information came as detail attributes from the first input, delete those attributes.

Release Notes

Version 0.0.2

Support for fracture grouping with a name attribute (H12+).

Warning

Introduced parameter changes that break backwards-compatibility.

  • parameter 'mode' became 'idmode'

  • a new 'mode' parameter is introduced

Version 0.0.1

Initial release.