Houdini 20.0 Nodes Geometry nodes

MotionClip Extract geometry node

Extracts the motion of joints over a set of frames from a MotionClip.

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Since 18.5

This SOP takes as input a MotionClip (for example, from the MotionClip SOP) and evaluates it at the given frames. If a requested frame is not stored in the clip, this node will interpolate between the neighboring cached frames.

The output geometry contains the requested joints from the given frames, assigning each point a time attribute that describes where it originated from.

Use the MotionClip Update SOP to take the modified output from this node and pack it back into a MotionClip.



These parameters determine how the poses of the MotionClip are extracted.

Output Mode

Specifies whether to output skeletons (Frames) or motion trails displaying lines that show the movement of each joint (Motion Trails).

Joint Group

A group of the topology skeleton’s points to be extracted. The topology is packed in primitive zero of the MotionClip.

Unpack Existing Samples

When turned on, the MotionClip is evaluated at all of the samples within the range.

This option is useful when working with sparse data and you only want to modify the keyframes, skipping the frames in between.

Clip Range

The source used to define the frame range and rate when extracting poses. This can be obtained from either the clipinfo detail attribute of the MotionClip or the Frame Range parameter.

Frame Range

Specifies the start/end/increment of the range of frames to be extracted. These values are based on the scene frame rate.

The Unpack Existing Samples parameter can be used to extract every frame in the Motion Clip within this range.

This parameter is available when Clip Range is set to Custom Frame Range.

End Behavior

Describes the behavior of the animation when it is evaluated outside the bounds of the MotionClip. When turned off, the left and right end behaviors are determined from the clipinfo detail attribute.


The first and last poses are extended out indefinitely.


The animation repeats from the beginning.

Mirrored Loop

The animation repeats in reverse.

Center of Mass

These parameters determine the center of mass of the skeleton and define how it is used.

Output Center of Mass

When turned on, creates a point at the center of mass of each extracted skeleton with a name defined by Point Name. The unpacked attributes for these points are taken from the first point of each extracted skeleton. If the Joint Group parameter is set, this point is at the center of mass of that group of joints.

Isolate Center of Mass

When turned on, deletes all the skeleton points so that only the points at the center of mass remains.

Point Name

The name of the point at the center of mass of each skeleton.

Configuration Attribute

The name of the dictionary point attribute on the rest pose of the MotionClip that defines the mass and local center of mass for each joint of the skeleton. This attribute can be created using the Configure Joints SOP.


These parameters determine the extra attributes that are unpacked from the MotionClip.

Unpack Attributes

When turned on, any attributes other than P, transform, name, path, and clipinfo are preset on the output geometry.

Turn off this parameter for maximum performance.

Rest Attributes

The attributes that should be unpacked from the rest pose of the MotionClip.

All groups, primitive attributes, and vertex attributes in the MotionClip are unpacked exclusively from the rest pose of the MotionClip.

Additionally, all animation attributes that are not matched by the Attributes to Store parameter on the MotionClip SOP can be unpacked from the rest pose of the MotionClip.

Animated Attributes

The attributes that should be evaluated from the animated poses of the MotionClip. These are the attributes that are matched by the Attributes to Store parameter on the MotionClip SOP.

If an attribute is unpacked from the rest pose, and evaluated from the animated poses, the animated attribute takes priority.



The MotionClip to extract from.


Extracted Geometries

The skeleton in a range of poses extracted from the MotionClip at the specified frames. If a joint does not exist at a frame, data is interpolated from surrounding frames.


SimpleMotionClipExtract Example for MotionClip Extract geometry node

This example demonstrates how to use the MotionClip Extract node to extract a series of frames from a motion clip.

See also

Geometry nodes