Houdini 20.0 Nodes Geometry nodes

MotionClip Blend 2.0 geometry node

Blends the animation of one MotionClip on top of another

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Since 19.0

This takes two MotionClips, a base and a layer, and overlays the layer on top of the base. The contribution of the layer can be faded in up to a maximum weight given by Effect, and then faded out.

You can also specify a group of joints that you want to layer.

The output clip length will be the union of the base clip and the segment being layered on top of it.

State

This viewport state allows you to visualize a MotionClip or its evaluated poses over time using a color ramp, and it is available for every MotionClip SOP node that outputs a MotionClip.

MotionClip viewport state interaction

You can select individual joints from the current pose in the MotionClip viewport state. For the selected joints, you can then use the Evaluate Pose mode to view just the current pose, its selected joints, and the motion trails for those joints.

rFoot and lFoot joints selected, Mode = Evaluate Pose, Color = White to Red
MotionClip viewport state toolbar

Mode

Determines the MotionClip information that is displayed in the viewport.

MotionClip

Displays all the MotionClip’s poses.

Mode = MotionClip

Evaluate Pose

Displays a single MotionClip pose at the current time.

Mode = Evaluate Pose

Transparent MotionClip

When turned on, the MotionClip’s poses are displayed as fainter lines, making it easier to see the scene behind the MotionClip, as well as the evaluated pose.

Color

Applies the selected color ramp preset to the MotionClip’s visualization in the viewport. This color ramp helps to visualize changes to the MotionClip or individual poses over time.

Mode = Evaluate Pose, Color = White to Red

Extend Color

Determines how the poses outside of the MotionClip’s defined animation start and end range are visualized in the viewport.

Hold

Holds the color values at the ends of the range.

Mode = MotionClip, Color = Plasma, Extended Color = Hold

Gray

Poses outside the animation start and end range are colored gray.

Mode = MotionClip, Color = Plasma, Extended Color = Gray

Hide

Hides the poses outside the animation start and end range.

Mode = MotionClip, Color = Plasma, Extended Color = Hide

Parameters

Group

Only the joints specified in this group will be blended.

Region

These parameters manage the range during which the layer animation will be layered on top of the base animation, the range during the layer will fade in, and the range during which the layer will fade out.

Sample Increment

The number of frames you want to increment between each sample of the blended section.

Blend In

Enable Blend

If this is disabled, the layer will immediately take full effect.

Start Frame

The frame at which to begin easing in the layer.

End Frame

The frame at which to finish easing in the layer.

Blend Out

Enable Blend

If this is disabled, the layer will not fade out.

Start Frame

The frame at which to begin easing out the layer.

End Frame

The frame at which to finish easing out the layer.

Locomotion

These parameters manage how the locomotion of the MotionClip will be computed and blended.

To blend the locomotion of the MotionClips, the locomotion is first computed for each MotionClip, then the linear and rotational velocities of each frame of each MotionClip is computed, blended, and sequenced. This creates a more natural path for the blended MotionClip to follow.

Locomotion

The method used to determine the locomotion of the MotionClips.

None

The locomotion of the MotionClips will not be computed and the MotionClips will be blended without considering velocity.

Existing Locomotion

The locomotion will be obtained from the __locomotion__ point of the MotionClips. This point should be created by the Extract Locomotion node and should be present in both MotionClips.

Compute Locomotion

The locomotion of the MotionClips will be computed by this node.

Locomotion Source

The source of the locomotion of the MotionClips.

Joint

A joint in the skeletons of the MotionClips will be used as a reference for extracting the locomotion.

Center of Mass

The center of mass of the skeletons of the MotionClips will be computed and used as a reference for extracting the locomotion.

This parameter is only available when Locomotion is set to Compute Locomotion.

Locomotion Joint

The name of the joint in the input MotionClips which drives the translation and rotation of the animations.

This parameter is only available when Locomotion Source is set to Joint.

COM Joint

Name of the COM joint in the input skeleton to use as reference for extracting the translation and orientation.

This parameter is only available when Locomotion Source is set to Center of Mass.

Configuration Attribute

The name of the configuration point attribute from which to read the mass and local_com attributes from. See /nodes/sop/kinefx__configurejoints.html.

This parameter is only available when Locomotion Source is set to Center of Mass.

Apply Locomotion

The output animation will be shifted by its locomotion.

This parameter is only available when Locomotion is set to Existing Locomotion.

Translation

Shift Axes

Choose on which axes to blend the velocities of the MotionClips. If an orientation method is specified, these axes will refer to the skeleton’s local translation axes. Otherwise, these axes refer to the world translation axes.

These parameter is only available when Locomotion is set to Compute Locomotion.

Orientation

These parameter manage how the orientation of the locomotion of the MotionClips will be computed and blended.

These parameters are only available when Locomotion is set to Compute Locomotion.

Method

Specify around which axes to blend the rotational velocities of the MotionClips. See below for details on the parameters for each of these options.

None

Do not blend rotational velocity.

Around Up Axis

Blend the rotational velocity around the Up axis of the character. The Up axis will be deduced from the viewport orientation option.

Up Axis

Specify which method to use when extracting the orientation around the Up axis. See below for details on the parameters for each of these options.

Use Joint Orientation

Extract the orientation by pulling out the Euler angles from the locomotion joint and uses those to extract orientation data around the chosen axis.

Direction Between Joints

Extract the orientation by specifying an extra joint and drawing a direction vector between the locomotion joint and the joint specified in Look At Joint. This direction vector will be projected on the relevant plane and used to determine the orientation around the chosen axis.

Look At Joint

Specify an extra joint that will act as the tip of the direction vector.

Around All Axes

Blend the rotational velocity around all axes of the character.

Custom

Customize which axis and which method you want to use for extracting the orientation of the character.

Rotation Order

Specify which rotation order to use when extracting the orientation from the character animation.

X Axis

Specify which method to use when extracting the orientation around the X axis. See the Up Axis above for details on the parameters for each of these options.

Y Axis

Specify which method to use when extracting the orientation around the Y axis. See the Up Axis above for details on the parameters for each of these options.

Z Axis

Specify which method to use when extracting the orientation around the Z axis. See the Up Axis above for details on the parameters for each of these options.

Attributes

These parameters are used to determine which attributes from the input MotionClips become animated on the output MotionClip.

For more details on what distinguishes an animated attribute from a rest attribute, see the Attributes folder on the MotionClip Evaluate SOP.

Tip

To maintain the attributes which were previously animated without adding any additional attributes to the poses, toggle Repack Attributes on, clear Rest Attributes, and set Animated Attributes to *.

Theses are the default values for these parameters.

Repack Attributes

When enabled, the attributes defined by the Rest Attributes and Animated Attributes patterns will be evaluated from the input MotionClips and packed into the output MotionClip’s poses. This will result in all of these attributes becoming animated attributes on the output MotionClip.

Rest Attributes

The attributes that should be unpacked from the rest pose of each input MotionClip. All attributes that match this pattern will become animated attributes on the output MotionClip.

Animated Attributes

The attributes that should be evaluated from the animated poses of the input MotionClips. All attributes that match this pattern will remain animated on the output MotionClip.

Blend

Locomotion

These parameters manage how the locomotion of the MotionClip should be blended. The parameters that affect the blend of the locomotion will be obtained from the parameters that affect the blend of a joint in the MotionClip.

Match Blend

The method of choosing the joint from which the parameters and attributes that affect the blend of the locomotion will be obtained.

None

No joint will be chosen and the locomotion will not be blended.

Locomotion Joint

If Locomotion is Compute Locomotion and Locomotion Source is Joint, the joint provided by the Locomotion Joint parameter will be chosen.

Otherwise, the __locomotion__ joint will be chosen.

Custom Joint

The joint provided by the Blend Joint parameter will be chosen.

Blend Joint

The parameters and attributes that affect the blend of the locomotion of this joint will be used to blend the locomotion of the animation.

This parameter is only available when Match Blend is set to Custom Joint.

Attributes

These parameters affect which attributes will be blended in the blend region and the shape of the blend for each joint.

Point Attributes

The point attributes of the joints which will be blended in addition to the P, transform, and localtransform attributes.

Blend Mode

The mode used to determine how each joint is blended.

All Joints

All joints are blended using the same parameters.

By Joint Group

A set of blending parameters can be defined for any number of joint groups.

By Attribute

The effect, blend shape, and bias will be determined from point attributes in the rest frame of one of the two clips.

All Joints

These parameters are visible when Blend Mode is set to All Joints.

Effect

The maximum weight of the layer. If this is animated with a channel, the whole SOP will become time dependent.

Effect Anim

The animated weight of each motion sample. If this is animated with a channel, the weight will be animated for each sample time.

Blend Type

The type of the blending function.

Linear

Linear shape.

Ease in

Smooth on entry.

Ease out

Smooth on exit.

Ease in Ease out

Smooth on entry and exit.

Bias

The bias of the blend. 0 biases toward the base and +1 biases towards the layer.

By Joint Group

These parameters are visible when Blend Mode is set to By Joint Group.

Number of Joint Groups

The number of joint groups to be layered on top of the base clip. If a joint belongs to multiple groups, it will be blended based upon the parameters for the first group to which it belongs.

Joint Group

A group of the layer topology skeleton’s joints to be overlayed.

Effect

The maximum weight of the layer for this joint group.

Blend Type

The type of the blending function for this joint group.

Linear

Linear shape.

Ease in

Smooth on entry.

Ease out

Smooth on exit.

Ease in Ease out

Smooth on entry and exit.

Bias

The bias of the blend for this joint group. 0 biases toward the base and +1 biases towards the layer.

By Attribute

These parameters are visible when Blend Mode is set to By Attribute.

Attribute Source

The MotionClip from which the attributes will be taken.

Base Clip

The attributes will be taken from the rest frame of the base clip.

Layer Clip

The attributes will be taken from the rest frame of the layer clip.

Effect Attribute

The name of the attribute which determines the effect.

Blend Type Attribute

The name of the attribute which determines the blend type.

Bias Attribute

The name of the attribute which determines the bias.

Inputs

Base MotionClip

The base MotionClip.

Layer MotionClip

The MotionClip layer you wish to overlay on top of the base.

Outputs

MotionClip

A MotionClip computed by blending the MotionClips on the first and second inputs together.

Examples

SimpleMotionClipBlend Example for MotionClip Blend geometry node

This example demonstrates how to use the MotionClip Blend node to blend an animation of someone being pushed while running forwards into an animation of someone jogging around a corner.

The final result is an animation of someone being pushed while jogging around a corner.

See also

Geometry nodes