Houdini 21.0 Nodes Geometry nodes

Guide Find Strays geometry node

Identifies stray guide curves based on root distance and other metrics.

Since 21.0

This SOP identifies guide curves that are isolated from others, which may need special treatment in certain hair and fur workflows. Stray guides are detected by comparing root distances to nearby guides and distance changes along each curve pair.

You can output strays as a primitive group or mask attribute. The mask attribute allows identifying part of a curve as stray.

Parameters

Reference Distance

Mode

The method for computing expected distances between guides.

Individual Root Distances

Compares each guide’s root to its immediate neighbors directly.

Root Distance Percentile

Uses a statistical model based on the distance percentile between guide roots.

Root Dist Percentile

The percentile used to determine a baseline expected root distance (e.g., 0.5 = median). Guides beyond this distance may be considered strays.

Min Dist Multiple

Minimum multiplier of the reference distance to consider a guide valid. Guides closer than this multiple are not marked as strays.

Max Dist Multiple

Maximum multiplier of the reference distance. Guides with distances exceeding this threshold are flagged as strays.

Group Threshold

Optional numeric threshold used when comparing attributes listed in Threshold Attributes.

Threshold Attributes

Apply group threshold to mask attributes, making them either 0 (not stray) or 1 (stray).

Primitive Group

Create Primitive Group

Create a primitive group containing all stray guide curves.

Output Primitive Group

Name of the primitive group that will store stray guides.

Primitive Mask

Create Primitive Mask Attribute

Adds primitive mask identifying stray guides.

Primitive Mask Attribute

Name of the output primitive mask attribute.

Point Mask

Create Point Mask Attribute

Adds a float mask attribute to the points of stray guides.

Propagate Mask Along Curve

Enables propagation of the point mask along each curve.

Propagation

Controls how mask is propagated along each guide:

Forward Minimum

Propagates the mask forward from root to tip, taking the minimum of current and next point at each step.

Forward Maximum

Propagates the mask forward from root to tip, taking the maximum of current and next point at each step.

Backward Minimum

Propagates the mask forward from tip to root, taking the minimum of current and next point at each step.

Backward Maximum

Propagates the mask forward from tip to root, taking the maximum of current and next point at each step.

Point Mask Attribute

Name of the output point attribute used for marking stray guide points.

See also

Geometry nodes