Houdini 20.0 Nodes Geometry nodes

Attribute Composite geometry node

Composites vertex, point, primitive, and/or detail attributes between two or more selections.

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The specified attributes of the ordered inputs are composited in sequence. The attributes are first scaled by the corresponding blending weights and then composited using the specified compositing operator.

Attributes can be explicitly specified in the attribute text fields via the following rules:

Parameters

Selection Index

Specifies the input to use when generating the cooked selection.

Attributes

Detail

Detail attributes to composite.

Primitives

Primitive attributes to composite.

Points

Point attributes to composite.

Vertices

Vertex attributes to composite.

Allow P Attribute

When turned on, patterns used in the Points parameter can match the P attribute.

Weights

Blend #

Controls the contribution of the geometry inputs.

Operators

Alpha Attribute

Attribute containing the alpha mask.

Compositing Operation

Operator to composite with. For the Mean, Max, and Min operators, the specified Alpha Attribute affords a per-point, per-primitive, or per-vertex weight distribution. The Over and Under operators perform two of the standard alpha blending operations where the alpha values are taken from the specified Alpha Attribute.

Mean

Determines the weighted average of the input attributes.

Max

Determines the maximum of the weighted input attributes.

Min

Determines the minimum of the weighted input attributes.

Over

Scales the incoming weighted input attribute by its alpha value and adds it to the current intermediate output attribute scaled by one minus that alpha value:

source * alpha + destination * (1 - alpha)

If the Alpha Attribute does not exist for a particular input, then the alpha mask for that input is assumed to be 1.

Under

Similar to the Over operator, but with the alpha weights swapped:

source * (1 - alpha) + destination * alpha

If the Alpha Attribute does not exist for a particular input, then the alpha mask for that input is assumed to be 1.

Examples

BlendAttr Example for Attribute Composite geometry node

This example demonstrates how to blend attributes using the Attribute Composite SOP.

See also

Geometry nodes