Houdini 21.0 Nodes Geometry nodes

Parallel Transport along Geometry geometry node

Quickly generate vector fields using parallel transport.

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Since 21.0

This node is useful to get started with a groom quickly by brushing a direction at a point over the entire surface by parallel transport along the shortest paths (geodesics) to the point. The input is a collection of source points and directions (black points and vectors below), and the output is a point attribute containing the extended vector field. It also provides the option to compute a radial vector fields as well. When multiple point sources are selected, the field is obtained by extending the values from the closest source point:

Only the connected components to the source group will have guides generated on it.

Parameters

Group

A subset of primitives in the input geometry whose attribute value will be set. Leave this blank to affect the attribute value for all points in the input.

Guide Attribute

This is the name of the guide point attribute to create.

Method

Method to generate the vector field from source data.

Parallel Transport

Extends guides from the source group parallel transport. Intuitively, this brushes the guide direction so that it is perfectly smooth everywhere except at a sparse set of curves where the brushed vectors disagree.

Radial Field

Computes a radial vector field emanating from the source points. No initial guides are needed for this method.

Source Guides Group

Start points to generate the guides from.

Attributes

Input Guide

3D vector attribute specifying a tangent direction (at each source point) to extend over the remainder of the surface. If the attribute is not valid, the node defaults to using an arbitrary (but fixed) direction for each point.

Global Rotation

Rotate all the generated guides uniformly around the surface normals.

Locals

See also

Geometry nodes