Houdini 20.0 Nodes VOP nodes

Pyro Blackbody VOP node

Converts a temperature value into color (chroma) and intensity according to the blackbody radiation model.

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Since 12.0

This node is designed to have most of its interface promoted up to the parent material. to promote the UI for this node, you must choose Promote Interface ▸ UI + Links + Inputs to trigger scripts on the node to promote and create parameters up on the parent node.


Field value

The input to the blackbody function. This is interpreted as a scale on the node’s Temperature parameter/input. If you connect an input of a data type with multiple components (such as a vector), the node will output the same data type with each component passed through the blackbody function separately.



If this checkbox is off, the node has no effect. This may be useful for debugging.

Temperature at 0 (K)

The temperature corresponding to an input value of 0.

Temperature at 1 (K)

The temperature corresponding to an input value of 1. For example, if this parameter is 5000 (the default), then an input value of 1 means a temperature of 5000 degrees Kelvin.

Tone mapping

The blackbody algorithm’s output has a huge dynamic range.


Squashes or stretches the low end of the generated intensity, similar to exposing a photograph for shadows.


Manipulates the high end of the generated intensity.

VOP nodes