Houdini 20.0 Nodes Geometry nodes

Connectivity geometry node

Creates an attribute with a unique value for each set of connected primitives or points.

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The default name for the attribute is class.

Each primitive or point is assigned a number from 0 to the number of connected sets minus 1. Two primitives or points that share the same number will be connected.

Parameters

Connectivity Type

Determines whether it is to be points that are classified or primitives. The attribute will be a point or primitive attribute depending on this setting.

Primitive Include Group

The group of primitives to include in connectivity calculations. Primitives not in this group are treated as if they are deleted. This could introduce new disconnections to the remaining geometry, resulting in empty classes that contain no primitive.

When Connectivity Type is primitive, excluded primitives have integer -1 and empty string as their classifications.

Point Include Group

This parameter only applies if Connectivity Type is set to Point.

The group of points to include in connectivity calculations. Points not in this group are treated as if they are deleted, which could introduce new disconnections to the geometry.

Points not in this group have integer -1 and empty string as their classifications.

Attribute

The name of the attribute to create.

Attribute Type

Specifies whether to create an integer or string attribute.

Prefix

When Attribute Type is String, this prefix is combined with the integer value to produce the string value for each element.

Local Variable

The name of the local variable to map the new class to. By default it is the ALL CAPS version of the attribute.

Seam Group

Available only in the Primitive Connectivity mode.

A group of edges that are treated as additional topological boundaries when determining primitive connectivity.

Use UV Connectivity

Available only in the Primitive Connectivity mode, and when no Seam Group is provided.

Normally, two primitives are considered connected if they share any points. If this is set, they are instead considered connected if they have vertices that have the same vertex texture coordinate.

Note that this applies to vertex texture attribute, not point texture attributes.

UV Attribute

The name of the texture coordinate attribute to use when Use UV Connectivity is on, defaulting to uv.

Examples

ConnectedBalls Example for Connectivity geometry node

This example demonstrates how to use an attribute generated by the Connectivity SOP to color different pieces of geometry from a DOPs simulation.

See also

Geometry nodes