Houdini 20.0 Nodes Geometry nodes

Attribute Blur geometry node

Blurs out (or “relaxes”) points in a mesh or a point cloud.

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Since 16.0

This node blurs any floating-point attributes, including position, color and texture coordinates.

Blurring point positions effectively smooths the geometry if points lie on a surface.

Tip

In order to maintain good performance on time dependent meshes, there is a second input that can be used to specify the geometry at one frame in time (rest geometry). This will be used to construct the necessary temporary data that OpenCL uses to compute the Laplacian smooth. You can use this to improve performance on time varying geometries.

Using Attribute Blur

  1. Select the points you want to smooth.

  2. Put down an Attribute Blur node.

You can change the blurring specifications in the parameter editor.

Parameters

Group

Subset of points to smooth.

Attributes

The attributes to blur. Multiple attributes can be blurred at the same time. If the field is blank, the node does nothing.

Method

Lets you choose different blurring models that have different effects on the point attributes.

Uniform

Blur attributes evenly regardless of their distance from one another.

Edge Length

Blur attributes accounting for the fact that some points are closer than others. This option preserves relative distances between points, which is especially useful when points on the input are unevenly distributed.

Blurring Iterations

The number of times the input geometry is blurred. The higher the number, the more blurring.

Mode

The mode chooses how to specify the size (or “strength”) of each blurring iteration.

Laplacian

Each iteration has the same size specified by the Step Size parameter

Volume Preserving

Iteration sizes are chosen to blur based on a noise frequency chosen by the Cutoff Frequency parameter

Custom

Lets the user provide the sizes of odd and even iterations manually.

Step Size

Size of each iteration when Mode is set to Laplacian.

Cutoff Frequency

Noise frequency to remove. The larger this value, the more it will keep the original shape of the geometry. This option controls the blur strength in Volume Preserving mode.

Odd Step Size

Size of each odd iteration. The first iteration has this size.

Even Step Size

Size of each even iteration. The second iteration has this size.

Weight Attribute

Optional point attribute used as a multiplier to each point displacement. The larger the weight, the stronger the blurring.

Alpha Attribute

If enabled, performs mask-aware blurring using the point attribute specified. Points with an alpha value of 0 have no influence on neighboring points, while points with an alpha value of 1 apply the full blurring effect to neighbors.

Pin Border Points

Fixes all points on unshared edges on a polygonal surface. These points will not be blurred. This option can help prevent holes on a surface geometry from being enlarged when blurring point positions.

Influence Type

Blurring relies on each point being able to see what its neighbors' attributes are. This parameter determines how points see their neighbors.

Connectivity

Neighbors are determined by mesh connectivity. Each point mixes its attribute value with the value of its neighbors to achieve blurring.

Proximity

Neighbors are determined by proximity. Each point has a maximum number of neighbors given by the Max Neighbors parameter, where each neighbor must be within a certain distance away given by the Proximity Radius parameter.

Proximity Radius

Determines how far points influence each other when Influence Type is set to proximity.

Max Neighbors

Determines the maximum number of neighbors each point is permitted to have. Large numbers of neighbors may reduce performance.

Enable Blending

If this checkbox is turned on, blends the blurred result with the original input additively. The blending amount is controlled by Original Blend Amount and Blurred Blend Amount.

Original Blend Amount

The original attribute values are multiplied by this value before being added to the result. This is ignored if Enable Blending is turned off.

Blurred Blend Amount

The blurred attribute values are multiplied by this value before being added to the result. This is ignored if Enable Blending is turned off.

See also

Geometry nodes