Houdini 21.0 Nodes VOP nodes

MtlX Chiang Hair BSDF VOP node

A BSDF node for Chiang hair shading model.

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Since 21.0

Constructs a hair BSDF based on the Chiang hair shading model described in “A Practical and Controllable Hair and Fur Model for Production Path Tracing”. This node does not support vertical layering.

Parameters

Tint R

Color multiplier for the first R-lobe.

Tint TT

Color multiplier for the first TT-lobe.

Tint TRT

Color multiplier for the first TRT-lobe.

Ior

Index of refraction. Defaults to 1.55 being the value for keratin.

Roughness R

Longitudinal and azimuthal roughness (ν, s) for the first R-lobe, range [0.0, inf). With (0, 0) specifying pure specular scattering.

Roughness Tt

Longitudinal and azimuthal roughness (ν, s) for the first TT-lobe, range [0.0, nf). With (0, 0) specifying pure specular scattering.

Roughness Trt

Longitudinal and azimuthal roughness (ν, s) for the first TRT-lobe, range [0.0, inf). With (0, 0) specifying pure specular scattering.

Cuticle Angle

Cuticle angle in radians, Values above 0.5 tilt the scales towards the root of the fiber, range /nodes/vop/0.0, 1.0.html. With 0.5 specifying no tilt.

Absorption Coefficient

Absorption coefficient normalized to the hair fiber diameter.

Normal

Normal vector of the surface. Defaults to world space normal.

Curve Direction

Direction of the hair geometry. Defaults to world space tangent.

Outputs

out

BSDF

VOP nodes