Houdini 20.0 Nodes VOP nodes

Specular Sheen VOP node

Generates a color using a specular lighting model with a Fresnel falloff calculation.

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This VOP uses a specular lighting model with a Fresnel falloff calculation to generate a color. Typically, adding this lighting model into the network, is the last thing done before connecting the resulting color to the output Cf input.



The normal vector is used in the sheen calculation.


The incidence direction ray used in the selected sheen calculation,

Sheen Intensity

A floating point value used to darken or lighten sheen highlight.

Sheen Color

The sheen highlight color. It is multiplied by the light color.

Index of Refraction

This value is the ratio of the speed of light in one medium, such as air, to that of another medium. This determines how much the ray bends as it passes into another material. In this context, it effects the amount of specular visible on the front of the surface. Higher values tend to “push” the specular towards the edges.


A floating point value used to control the size or spread of the sheen highlight.

face forward

This toggle will change the normal to face forward towards the camera. It is recommended this toggle be on.



The sheen highlight calculation.

Ksheen \* sheenColor * sheen(nN, nI, eta, urough)


The sheen lighting without the multiplication by the sheen intensity or the sheen color. Usually used as an export parameter for extra images planes used in the composite.


The PBR sheen calculation.

See also

VOP nodes