Houdini 21.0 Nodes Geometry nodes

Labs Calculate Thickness 1.0 geometry node

Computes an approximate thickness value for geometry using inward ray casting.

This node estimates geometric thickness by casting rays inward from the surface, similar in principle to ambient occlusion but inverted in direction. The resulting thickness values represent an approximation of how much geometry exists behind a surface point and can be used for effects such as inexpensive subsurface scattering masks, wear masks, or material modulation.

This method is an approximation and trades physical accuracy for performance.

Parameters

Thickness Settings

Number of Rays

Number of rays cast per sample. Higher values increase quality at the cost of performance.

Maximum Ray Distance

Maximum distance a ray is allowed to travel, in world units. Increase this value for larger-scale geometry.

Advanced

Ray Direction

Direction used for casting thickness rays. By default, the node computes an appropriate inward direction automatically. Use this parameter to override the direction in special cases. Input normals are expected to point outward.

Minimum Ray Distance

Minimum distance a ray must travel before contributing to thickness. Increasing this value increases contrast in the result.

Cone Angle

Maximum angular deviation, in degrees, from the central ray direction.

Seed

Seed used for ray sampling variation.

Output

Output Thickness as Color ( Cd )

Writes the thickness result to the point attribute Cd.

Normalized

Outputs thickness values normalized to the 0–1 range instead of world units.

Thickness Attribute

Name of the output attribute when Output Thickness as Color (Cd) is turned off.

Output curve

Remaps the computed thickness values. This curve allows basic level adjustments without recomputing the thickness rays.

Geometry nodes