Houdini 20.0 Nodes VOP nodes

Hair Diffuse VOP node

Generates a color specifically for curves (hairs) using a lambert lighting model calculation.

This node type is deprecated. It is scheduled to be deleted in an upcoming revision of Houdini.

Use the Physically Based Hair Model node instead.

(Since version 12.5.)

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This VOP uses the hair lambert lighting model calculation to generate a color for curves (hairs). Typically, adding this lighting model into the network, is the last thing done before connecting the resulting color to the output Cf input.


This is cannot be used with PBR.


Diffuse Color

The diffuse color of the hair.

Diffuse Intensity

A multiplier which allows you to adjust the intensity of the diffuse color.



This normal should be the explicitly connected to the specially calculated hair normal VOP. In this VOP the normal is already front facing and normalized.


The diffuse intensity. A floating point value used to darken or lighten diffuse color.


The diffuse color. Usually with hair, a root and a tip color are specified. These 2 colors are mix along the length of the hair using the geometric or global t coordinate.



The diffuse lighting calculation.

Kd * diff * Cl * abs(dot(nN, nL))


Just hair diffuse lighting without the multiplication by the diffuse intensity and color. Usually used as an export parameter for extra image planes used in the composite of the final image.


Returns the PBR wirediffuse function calculation.

Kd * diff * wirediffuse(normalize(dPdt))
See also

VOP nodes