This reference page is linked to from the following overview topics: Maya Architecture Overview, Skinning, Example C++ plug-in descriptions.

skinCluster function set

MFnSkinCluster is the function set for skinClusters. SkinCluster nodes are created during a smooth bindSkin. The purpose of the skinCluster is to store a weight per influence object for each component of each geometry that is deformed. Influence objects can be joints or any transform.

Note that unlike most deformers, a skinCluster node can deform only a single geometry. Therefore, if additional geometries are added to the skinCluster set, they will be ignored.

This function set provides methods for getting and setting weights on skin cluster nodes. It parent class, MFnGeometryFilter provides methods for accessing the skin cluster's input and output geometry.

**Examples:**

`#include <MFnSkinCluster.h>`

Inheritance diagram for MFnSkinCluster:

## Public Member Functions | |

virtual MFn::Type | type () const |

Function set type. | |

virtual | ~MFnSkinCluster () |

Destructor. | |

MFnSkinCluster () | |

Default constructor. | |

MFnSkinCluster (MObject &object, MStatus *ReturnStatus=NULL) | |

Constructor. | |

MStatus | getWeights (const MDagPath &path, const MObject &components, unsigned int influenceIndex, MDoubleArray &weights) const |

Gets the skinCluster weights for the influence object for the specified components of the object whose dagPath is specified. | |

MStatus | getWeights (const MDagPath &path, const MObject &components, MDoubleArray &weights, unsigned int &influenceCount) const |

Gets the skinCluster weights for all influenceObjects for the specified components of the object whose dagPath is specified. | |

MStatus | getWeights (const MDagPath &path, const MObject &components, MIntArray &influenceIndices, MDoubleArray &weights) const |

Gets the skinCluster weights for the influence objects for the specified components of the object whose dagPath is specified. | |

MStatus | setWeights (const MDagPath &path, const MObject &components, unsigned int jointIndex, double value, bool normalize=true, MDoubleArray *oldValues=NULL) |

Sets the skinCluster weight for the influence object on the specified components of the object whose dagPath is specified. | |

MStatus | setWeights (const MDagPath &path, const MObject &components, MIntArray &influenceIndices, MDoubleArray &values, bool normalize=true, MDoubleArray *oldValues=NULL) |

Sets the skinCluster weight on the specified components of the object whose dagPath is specified for the influence objects corresponding to the specified influence indices. | |

MStatus | getPointsAffectedByInfluence (const MDagPath &path, MSelectionList &result, MDoubleArray &weights) |

During deformation, the skinCluster algorithm is applied for a given influence object on all points in the deformer's set whose weights are non-zero. | |

unsigned int | indexForInfluenceObject (const MDagPath &path, MStatus *ReturnStatus=NULL) const |

Returns the logical index of the matrix array attribute where the specified influence object is attached. | |

unsigned int | influenceObjects (MDagPathArray &paths, MStatus *ReturnStatus=NULL) const |

Returns an array of paths to the influence objects for the skinCluster. | |

MStatus | getWeights (const MDagPath &path, const MObject &components, unsigned int influenceIndex, MFloatArray &weights) const |

This method is obsolete. | |

MStatus | getWeights (const MDagPath &path, const MObject &components, MFloatArray &weights, unsigned int &influenceCount) const |

This method is obsolete. | |

MStatus | setWeights (const MDagPath &path, const MObject &components, unsigned int jointIndex, float value, bool normalize=true, MFloatArray *oldValues=NULL) |

This method is obsolete. | |

MStatus | setWeights (const MDagPath &path, const MObject &components, MIntArray &influenceIndices, MFloatArray &values, bool normalize=true, MFloatArray *oldValues=NULL) |

This method is obsolete. | |

MStatus | getPointsAffectedByInfluence (const MDagPath &path, MSelectionList &result, MFloatArray &weights) |

This method is obsolete. | |

MStatus | getBlendWeights (const MDagPath &path, const MObject &components, MDoubleArray &weights) const |

This method returns weights from skinCluster's blend weight array. | |

MStatus | setBlendWeights (const MDagPath &path, const MObject &components, const MDoubleArray &weights) |

This method sets weights in skinCluster's blend weight array. | |

MFnSkinCluster (const MObject &object, MStatus *ReturnStatus=NULL) | |

Constructor. | |

## Protected Member Functions | |

virtual const char * | className () const |

Class name. |

MFnSkinCluster | ( | MObject & | object, |

MStatus * | ReturnStatus = `NULL` |
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) |

Constructor.

Class constructor that initializes the function set to the given MObject.

**Parameters:**-
[in] object The MObject to attach the function set to [out] ReturnStatus the return status

**Status Codes:****MS::kSuccess**if the function set is successfully attached**MS::kInvalidParameter**if the MObject does not represent a valid Maya object or if the function set is not allowed to attach to this MObject

MFnSkinCluster | ( | const MObject & | object, |

MStatus * | ReturnStatus = `NULL` |
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) |

Constructor.

Class constructor that initializes the function set to the given MObject.

**Parameters:**-
[in] object The MObject to attach the function set to [out] ReturnStatus the return status

**Status Codes:****MS::kSuccess**if the function set is successfully attached**MS::kInvalidParameter**if the MObject does not represent a valid Maya object or if the function set is not allowed to attach to this MObject

MFn::Type type | ( | ) | const` [virtual]` |

Function set type.

Return the class type : MFn::kSkinClusterFilter.

Reimplemented from MFnGeometryFilter.

MStatus getWeights | ( | const MDagPath & | path, |

const MObject & | components, |
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unsigned int | influenceIndex, |
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MDoubleArray & | weights |
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) | const |

Gets the skinCluster weights for the influence object for the specified components of the object whose dagPath is specified.

Note that if some of components are not deformed by the skinCluster, zeros will be returned as the weights. For example, on periodic nurbs surfaces, some of the cvs enforce the periodicity of the surface. There is no weight data for these components. They do not get deformed since their position is automatically maintained by the nurb so that the periodicity of the surface will not be lost. Zeros will be returned for such components.

The influence object is specified using the physical (non-sparse) index of the influence object. This corresponds to the order the influences are returned by the influenceObjects method.

The length of the returned array will be equal to the number of specified components. The values in the returned array will be ordered in the same order as the input components.

**Parameters:**-
[in] path path to object deformed by the skinCluster [in] components components to return weights for [in] influenceIndex physical index of influence object [out] weights weight values

**Returns:**- The status

**Status Codes:****MS::kSuccess**operation successful**MS::kFailure**operation failed**MS::kInvalidObjectType**component was invalid, shape was not attached to skinCluster, or invalid influenceIndex was specified

MStatus getWeights | ( | const MDagPath & | path, |

const MObject & | components, |
||

MDoubleArray & | weights, |
||

unsigned int & | influenceCount |
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) | const |

Gets the skinCluster weights for all influenceObjects for the specified components of the object whose dagPath is specified.

Returns the weights in an array of size number of components x number of influenceObjects. The array elements are ordered by components: i.e. all of the weight values for the first component first, followed by all the weight values for the next component, and so on. For the first component, the weights are ordered by influence object in the same order that is returned by the MFnSkinCluster::influenceObjects method.

The number of influence objects is returned in influenceCount.

**Parameters:**-
[in] path path to object deformed by the skinCluster [in] components components to return weights for [out] weights weight values returned (one per component, per influence) [out] influenceCount count of influence objects

**Returns:**- The status

**Status Codes:****MS::kSuccess**operation successful**MS::kFailure**operation failed**MS::kInvalidObjectType**component was invalid, shape was not attached to skinCluster, or invalid influenceIndex was specified

MStatus getWeights | ( | const MDagPath & | path, |

const MObject & | components, |
||

MIntArray & | influenceIndices, |
||

MDoubleArray & | weights |
||

) | const |

Gets the skinCluster weights for the influence objects for the specified components of the object whose dagPath is specified.

Returns the weights in an array of size number of components x number of influence objects. The array elements are ordered by components: i.e. all of the weight values for the first component first, followed by all the weight values for the next component, and so on. For the first component, the weights are ordered by influence object in the same order as in influenceIndices.

**Parameters:**-
[in] path path to object deformed by the skinCluster [in] components components to return weights for [in] influenceIndices indices of influence objects to get [out] weights weight values returned (one per component, per influence)

**Returns:**- The status

**Status Codes:****MS::kSuccess**operation successful**MS::kFailure**operation failed**MS::kInvalidObjectType**component was invalid, shape was not attached to skinCluster, or invalid influenceIndex was specified

MStatus setWeights | ( | const MDagPath & | path, |

const MObject & | components, |
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unsigned int | influenceIndex, |
||

double | value, |
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bool | normalize = `true` , |
||

MDoubleArray * | oldValues = `NULL` |
||

) |

Sets the skinCluster weight for the influence object on the specified components of the object whose dagPath is specified.

The influence is specified using the physical (non-sparse) index of the influence object. This corresponds to the order the influences are returned by the influenceObjects method.

In order to undo the setWeight operation, it is necessary to save the oldValues array and call setWeight with the oldValues array at the time of undo. The number of oldValues returned will be of size number of specified components x the total number of influence objects. The values in the oldValues array will be ordered with first the all the values for the first component, then all the values for the next, and so on.

Note that unlike most deformers, a skinCluster node can deform only a single geometry. Therefore, if additional geometries are added to the skinCluster set, they will be ignored, and weights cannot be set for the additional geometry.

**Parameters:**-
[in] path path to object deformed by the skinCluster [in] components components to be weighted [in] influenceIndex physical index of influence object for the weight [in] value weight value [in] normalize whether or not to normalize weights on other influence objects [in] oldValues previous weight values, for undo

**Returns:**- The status

**Status Codes:****MS::kSuccess**operation successful**MS::kFailure**operation failed**MS::kInvalidObjectType**component or influence index was invalid, or shape was not attached to skinCluster

MStatus setWeights | ( | const MDagPath & | path, |

const MObject & | components, |
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MIntArray & | influenceIndices, |
||

MDoubleArray & | values, |
||

bool | normalize = `true` , |
||

MDoubleArray * | oldValues = `NULL` |
||

) |

Sets the skinCluster weight on the specified components of the object whose dagPath is specified for the influence objects corresponding to the specified influence indices.

The influence is specified using the physical (non-sparse) index of the influence object. This corresponds to the order the influences are returned by the influenceObjects method.

If you want to set the same values on all of the specified components, the number of values in the values array should equal the number of indices in the influence indices array. If you want to specify a unique value for each component, the number of values in the values array should equal the number of components x the number of indices in the influence indices array. The ordering of the values array should be such that first all the values for the first component are listed, then the second, and so on. For example, if you want to set the weights for three components for influences 7 and 10, the influence array would contain [7,10], and the values array would contain: [component#1 weight for influence 7, component #1 weight for influence 10, component#2 weight for influence 7, component#2 weight for influence 10, ...].

In order to undo the setWeights operation, it is necessary to save the oldValues array and call setWeights with the oldValues array at the time of undo. The number of oldValues returned will be of size number of components x total number of influence objects. The values in the oldValues array will be ordered with first the all the values for the first component, then all the values for the next, and so on.

Note that unlike most deformers, a skinCluster node can deform only a single geometry. Therefore, if additional geometries are added to the skinCluster set, they will be ignored, and weights cannot be set for the additional geometry.

**Parameters:**-
[in] path path to object deformed by the skinCluster [in] components components to be weighted [in] influenceIndices physical indices of influence objects to set [in] values weight values [in] normalize whether or not to normalize weights on other influence objects [in] oldValues previous weight values, for undo

**Returns:**- The status

**Status Codes:****MS::kSuccess**operation successful**MS::kFailure**operation failed**MS::kInvalidObjectType**component was invalid, or shape was not attached to skinCluster, or invalid influenceIndices were specified

MStatus getPointsAffectedByInfluence | ( | const MDagPath & | path, |

MSelectionList & | result, |
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MDoubleArray & | weights |
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) |

During deformation, the skinCluster algorithm is applied for a given influence object on all points in the deformer's set whose weights are non-zero.

This method allows the user to query the non-zero weights for a particular influence object.

Returns a selection list containing the dag path and the components that are affected by the specified influence object. To retrieve the components from the returned MSelectionList, use MSelectionList::getDagPath. Also returns the corresponding weights for the components. If no components are weighted for a specified influence, the resulting selection list will be empty.

**Parameters:**-
[in] path path of the influence object [out] result selection list of components affected by the influence object for this skinCluster (return) [out] weights weights for the affected components (return)

**Returns:**- Return status

**Status Codes:****MS::kSuccess**operation successful**MS::kFailure**operation failed, or path is not an influence object

unsigned int indexForInfluenceObject | ( | const MDagPath & | mpath, |

MStatus * | ReturnStatus = `NULL` |
||

) | const |

Returns the logical index of the matrix array attribute where the specified influence object is attached.

**Parameters:**-
[in] mpath path of the influence object [out] ReturnStatus return status

**Returns:**- The logical index of the influence object

**Status Codes:****MS::kSuccess**operation successful**MS::kFailure**operation failed, or transform is not an influence object

unsigned int influenceObjects | ( | MDagPathArray & | paths, |

MStatus * | ReturnStatus = `NULL` |
||

) | const |

Returns an array of paths to the influence objects for the skinCluster.

**Parameters:**-
[in] paths influence objects [out] ReturnStatus return status

**Returns:**- The number of influence objects

**Status Codes:****MS::kSuccess**operation successful**MS::kFailure**operation failed

MStatus getWeights | ( | const MDagPath & | path, |

const MObject & | components, |
||

unsigned int | influenceIndex, |
||

MFloatArray & | weights |
||

) | const |

This method is obsolete.

Maya's skinCluster nodes store their weights as doubles. This method has been replaced by one which uses doubles instead of floats. This method only exists for backwards-compilability of old plug-in code.

**Parameters:**-
[in] path path to object deformed by the skinCluster [in] components components to return weights for [in] influenceIndex index of influence object [out] weights weight values

**Returns:**- The status

**Status Codes:****MS::kSuccess**operation successful**MS::kFailure**operation failed**MS::kInvalidObjectType**component was invalid, shape was not attached to skinCluster, or invalid influenceIndex was specified

MStatus getWeights | ( | const MDagPath & | path, |

const MObject & | components, |
||

MFloatArray & | weights, |
||

unsigned int & | influenceCount |
||

) | const |

This method is obsolete.

Maya's skinCluster nodes store their weights as doubles. This method has been replaced by one which uses doubles instead of floats. This method only exists for backwards-compilability of old plug-in code.

**Parameters:**-
[in] path path to object deformed by the skinCluster [in] components components to return weights for [out] weights weight values returned (one per component, per influence) [out] influenceCount count of influence objects

**Returns:**- The status

**Status Codes:****MS::kSuccess**operation successful**MS::kFailure**operation failed**MS::kInvalidObjectType**component was invalid, shape was not attached to skinCluster, or invalid influenceIndex was specified**MS::kInvalidParameter**operation failed, NULL MObject passed or the MObject does not support components

MStatus setWeights | ( | const MDagPath & | path, |

const MObject & | components, |
||

unsigned int | influenceIndex, |
||

float | value, |
||

bool | normalize = `true` , |
||

MFloatArray * | oldValues = `NULL` |
||

) |

This method is obsolete.

Maya's skinCluster nodes store their weights as doubles. This method has been replaced by one which uses doubles instead of floats. This method only exists for backwards-compilability of old plug-in code.

**Parameters:**-
[in] path path to object deformed by the skinCluster [in] components components to be weighted [in] influenceIndex index of influence object for the weight [in] value weight value [in] normalize whether or not to normalize weights on other influence objects [in] oldValues previous weight values, for undo

**Returns:**- The status

**Status Codes:****MS::kSuccess**operation successful**MS::kFailure**operation failed**MS::kInvalidObjectType**component was invalid, or shape was not attached to skinCluster, or invalid influenceIndex was specified

MStatus setWeights | ( | const MDagPath & | path, |

const MObject & | components, |
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MIntArray & | influenceIndices, |
||

MFloatArray & | values, |
||

bool | normalize = `true` , |
||

MFloatArray * | oldValues = `NULL` |
||

) |

This method is obsolete.

**Parameters:**-
[in] path path to object deformed by the skinCluster [in] components components to be weighted [in] influenceIndices indices of influence objects to set [in] values weight values [in] normalize whether or not to normalize weights on other influence objects [in] oldValues previous weight values, for undo

**Returns:**- The status

**Status Codes:****MS::kSuccess**operation successful**MS::kFailure**operation failed**MS::kInvalidObjectType**component was invalid, or shape was not attached to skinCluster, or invalid influenceIndices was specified

MStatus getPointsAffectedByInfluence | ( | const MDagPath & | path, |

MSelectionList & | result, |
||

MFloatArray & | weights |
||

) |

This method is obsolete.

**Parameters:**-
[in] path path of the influence object [out] result selection list of components affected by the influence object for this skinCluster (return) [out] weights weights for the affected components (return)

**Returns:**- Return status

**Status Codes:****MS::kSuccess**operation successful**MS::kFailure**operation failed, or path is not an influence object

MStatus getBlendWeights | ( | const MDagPath & | path, |

const MObject & | components, |
||

MDoubleArray & | weights |
||

) | const |

This method returns weights from skinCluster's blend weight array.

These weights are used to determine the blending between classical linear skinning and dual quaternion bases skinning on a per vertex basis. The function returns the weights associated with the components passed. The components are defined on the object whose dagPath is specified.

**Parameters:**-
[in] path path to object deformed by the skinCluster [in] components the components to return weights for [out] weights the weight values returned (one per component in the order given)

**Returns:**- The status

**Status Codes:****MS::kSuccess**operation successful**MS::kFailure**operation failed**MS::kInvalidObjectType**component was invalid, shape was not attached to skinCluster.

MStatus setBlendWeights | ( | const MDagPath & | path, |

const MObject & | components, |
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const MDoubleArray & | weights |
||

) |

This method sets weights in skinCluster's blend weight array.

These weights are used to determine the blending between classical linear skinning and dual quaternion bases skinning on a per vertex basis. The function sets the weights for the given components of the object whose dagPath is specified. The array size should match the number of components passed. Failing this, it will set the smaller of the two.

**Parameters:**-
[in] path path to object deformed by the skinCluster [in] components the components list for the new weight values [out] weights the weight values (one per component in the order given)

**Returns:**- The status

**Status Codes:****MS::kSuccess**operation successful**MS::kFailure**operation failed**MS::kInvalidObjectType**component was invalid, shape was not attached to skinCluster.