skinCluster

Smooth Skin Attributes

Note: skinCluster weights are exposed so you can extract skin weight data from the skinCluster node. Access to the skin weight data lets you use Skin Cluster influence weights in falloff networks. See Create deformer falloffs.

Skinning Method

Specify which skinning method you want to use for the selected deformable object. See also Smooth skinning methods for more information.

Classic Linear

Sets the object to use classic linear skinning. Use this mode if you want basic smooth skin deformation effects, the same as in previous versions of Maya. This mode allows some volume shrinking and collapse deformation effects to occur.

When a mesh is set to linear skinning, it can lose volume in areas where it is influenced by a joint that is twisting on its axis.

Dual Quaternion

Sets the object to use dual quaternion skinning. Use this method if you’re concerned with preserving volume in the mesh as it deforms around joints that twist.

When a mesh is set to use dual quaternion skinning, volume is preserved even as it is influenced by a joint twisting on its axis.

Weight Blended

Sets the object to use a blend of classic linear and dual quaternion skinning, based on a per-vertex weight map that you paint. See Blend smooth skinning methods.

Use Components

Specifies whether changes to the components of smooth skin influence objects can change their deformation effects on smooth skin objects. If Use Components is off (the default), changes to components do not change the deformation effect. If Use Components is on, changes to components can change the deformation effect.

For example, if your smooth skin influence objects are NURBS surfaces and Use Components is on, moving the influence object CVs can change the deformation effect.

Alternatively, if your smooth skin influence objects are polygonal surfaces (meshes), setting Use Components on makes it possible for changes to individual polygons to in turn deform skin. Otherwise, with Use Components off, the entire shape of the influence object influences the skin but changes to individual polygons can not influence the skin.

Use Components is off by default.

Deform User Normals

When on, the normals of the smooth skinned geometry deform with the skin if the skin has user-defined custom normals. If the skin does not have user-defined custom normals, turning on this option will have no affect. Deform User Normals is on by default.

You can turn this option off to make the skin evaluate faster. For example, if you are animating a skeleton or viewing your character’s skin in wireframe mode, then you do not need the skin normals to deform.

Relative Space Matrix

The Relative Space Matrix is a 4 x 4 array of floats that represent the translation, rotation, scale, and sheer of a transform node, letting you add a matrix so you can edit its values. (You can also view and edit, in a separate tab, its composition.)

The values in both the Composition and Matrix tabs are linked, as they represent the same transformation but in two different ways. If you change the values in the Composition tab, it affects values in the Matrix tab, and the same is true in the inverse.

See Transform Offset Parent Matrix for more.

Relative Space Mode

Select a node evaluation space from the menu: World, Local, or Custom:

Space	Function
World	(Default) Uses the center of the scene as the origin.
Local	Uses the geometry space for evaluation.
Custom	Use an external matrix as the space for evaluation.

Use Local for skinClusters to simplify USD Skeleton import, where instead of disabling Inherit Parent transform, you can connect the new attribute to the skin cluster. Setting a Relative Space Mode lets you avoid issues if double deformations or transformations occur when the geometry parent is moved.

Note:

A warning is shown if parents of transforms do not match the space mode. If the geometry has no local values for transformation, objects are parented to the parent of the geometry instead of the geometry.

.

Support non-rigid transformations

When on, lets you animate bone scaling on the skinCluster node and activates the Scale settings.

Use Support non-rigid transformations to enable non-rigid transformations (such as scale and shear) in dual-quaternion or blended-skinning modes.

Scale

Lets you apply global scaling.

This attribute is useful as it globally scales DQS deformations with dual quaternion or blended modes when rescaling a bound character to a different size scene (where non-rigid transformations are enabled).

Normalize Weights

This drop-down list lets you set how you want smooth skin weights normalized. These options can help you avoid letting the normalization process unintentionally set small weight values across many vertices.

Select from the following options:

Interactive

When on, Maya normalizes skin weight values as you add or remove influences, and as you paint skin weights. (This is the default.)

As you work, Maya adds or removes weights from other influences in order to make the total weights on all influences add up to 1.0. You can view the exact weights used for deformation on the skinCluster node weightList attribute.

For example, if you change a weight from 1.0 to 0.5, Maya distributes the remaining 0.5 amongst neighboring influences. This mode replicates the normalization process in previous versions of Maya.

Use the Weight Distribution setting to determine how Maya creates new weights during normalization, if necessary.

None

Turns off smooth skin weight normalization.

Attention: Be aware that this option lets you create weights of greater than one or less than one, which can allow for odd or incorrect deformation as you exercise the character.

Post

When on, Maya calculates normalized skin weight values as you deform the mesh, preventing any odd or incorrect deformation. No normalized weight values are stored on the mesh, which lets you continue painting weights or adjusting interactive bind manipulators without having the normalization process change your previous skin weighting work.

Selecting this mode lets you paint or change weights without affecting the weights for other influences, and still have the skin normalization occur when you deform the mesh.

Note: Since Maya calculates the normalized weight values dynamically at deformation time, you cannot view the normalized values on the skinCluster node weightList attribute. Your mesh will deform with normalized values, but the actual weight values on your skinCluster node may add up to more or less than 1.

If you use interactive skin binding, this mode is automatically selected for you. (See Interactive bind for smooth skinning.) As a result, for interactive binding, weights are not normalized until you deform the mesh.

For more information on skin weight normalization, see Smooth skin weight normalization and Set normalization mode and normalize weights.

Weight Distribution

Available only when Normalize Weights mode is set to Interactive.

When you paint weights with Interactive normalization mode, Maya re-normalizes weight values after each stroke, scaling the available weights (those that already have some value and are not locked), so that the vertex weights still add up to 1.0. When possible, weights are scaled based on their existing value.

In situations where all other unlocked, available weights are zero, this setting lets you determine how Maya creates new weights during normalization.

Note: This setting also applies as you change weights in the Component Editor.

Select from the following:

Distance

Calculates new weights based on the distance of the vertex from the various influences to which it is skinned. Closer joints are given a higher weight. (This is the default).

Neighbors

Calculates new weights based on the influences affecting the surrounding vertices. This prevents the vertex from getting weights to every joint in the skeleton, and gives it similar weights to the surrounding vertices. Only supported for polygon meshes.

Max Influences

Specifies the number of joints that can influence each skin point on your smooth skin geometry. Default is 5, which produces good smooth skinning results for most characters. You can also limit the range of joint influence by specifying a Dropoff/Falloff Rate.

Maintain Max Influences

When on, your smooth skinned geometry cannot have, at any time, a number of influences greater than that specified by Max Influences.

For example, if Max Influences is set to 3, and you paint or set weights for a fourth joint, one of the weights of the other three joints is set to 0 to maintain the total number of weighted influences specified by Max Influences.

This limits the redistribution of weights to a specific number of influences, and ensures that the primary joints are the ones that receive the weights.

Note: If you turn on Maintain Max Influences in the Attribute Editor, the skin weights are not modified until you reassign them by clicking Update Weights.