Houdini 21.0 Nodes Geometry nodes

Motion Mixer Smooth geometry node

Defines a smooth effect for the motion mixer.

Since 21.0
This feature is still under development. The current functionality is unfinished and subject to change, and may have thin or no documentation. Please bear this in mind when using it.

The motion mixer’s smooth effect smooths out unwanted noise by applying a Butterworth filter to remove the frequencies that exceed a specified cut-off frequency, similar to the Smooth Motion SOP. This node defines an APEX graph that performs a smooth effect on the MixerAnim.skel of a single character. MixerAnim.skel is a skeleton that contains the control transforms of the character, and is output by the motion mixer.

This effect is invoked internally by the Motion Mixer SOP and uses multiple MixerAnim.skel samples. See smooth effect for more information.

Parameters

Pattern

A pattern that filters for a subset of skeleton joints on MixerAnim.skel. Only the specified joints are affected by the smoothing effect. This field accepts APEX path patterns, for example, “#L_*”.

Type

The type of filter to use.

Butterworth

This filter has a maximally flat magnitude in the passband, and is only available for low-pass and high-pass filters.

Order

The order of the filter. Determines how steeply the filter curve rolls off after the cutoff frequency. Higher orders correspond to a steeper roll off. This is only used by Butterworth filters.

Cutoff Frequency

The cutoff frequency for the filter, in hertz. Frequencies over this value are filtered out.

Components

Applies the filter to the translation, rotation, and/or scale components.

Transform Order

The transformation order to use when cracking and rebuilding the transformation matrices:

  • Scale Rot Trans

  • Scale Trans Rot

  • Rot Scale Trans

  • Rot Trans Scale

  • Trans Scale Rot

  • Trans Rot Scale

Rotate Order

The rotation order to use when cracking and rebuilding the transformation matrices:

  • Rx Ry Rz

  • Rx Rz Ry

  • Ry Rx Rz

  • Ry Rz Rx

  • Rz Rx Ry

  • Rz Ry Rx

Window

The number of frames to evaluate around the current frame. A window of 0 evaluates only the current frame. A value of 1 evaluates 1 frame before the current frame, the current frame, and 1 frame after the current frame.

Rate

The sampling rate, in frames per second, when computing the frames for the window.

See also

Geometry nodes