MFnSkinCluster Class Reference
[OpenMayaAnim - API module for animation, FunctionSet classes]

#include <MFnSkinCluster.h>

Inheritance diagram for MFnSkinCluster:

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Collaboration diagram for MFnSkinCluster:

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List of all members.

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Detailed Description

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:

exportSkinClusterDataCmd.cpp.

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
MStatus	getWeights (const MDagPath &path, const MObject &components, MDoubleArray &weights, unsigned int &influenceCount) const
MStatus	getWeights (const MDagPath &path, const MObject &components, MIntArray &influenceIndices, MDoubleArray &weights) const
MStatus	setWeights (const MDagPath &path, const MObject &components, unsigned int jointIndex, double value, bool normalize=true, MDoubleArray *oldValues=NULL)
MStatus	setWeights (const MDagPath &path, const MObject &components, MIntArray &influenceIndices, MDoubleArray &values, bool normalize=true, MDoubleArray *oldValues=NULL)
MStatus	getPointsAffectedByInfluence (const MDagPath &path, MSelectionList &result, MDoubleArray &weights)
unsigned int	indexForInfluenceObject (const MDagPath &path, MStatus *ReturnStatus=NULL) const
unsigned int	influenceObjects (MDagPathArray &paths, MStatus *ReturnStatus=NULL) const
MStatus	getWeights (const MDagPath &path, const MObject &components, unsigned int influenceIndex, MFloatArray &weights) const
MStatus	getWeights (const MDagPath &path, const MObject &components, MFloatArray &weights, unsigned int &influenceCount) const
MStatus	setWeights (const MDagPath &path, const MObject &components, unsigned int jointIndex, float value, bool normalize=true, MFloatArray *oldValues=NULL)
MStatus	setWeights (const MDagPath &path, const MObject &components, MIntArray &influenceIndices, MFloatArray &values, bool normalize=true, MFloatArray *oldValues=NULL)
MStatus	getPointsAffectedByInfluence (const MDagPath &path, MSelectionList &result, MFloatArray &weights)
MStatus	getBlendWeights (const MDagPath &path, const MObject &components, MDoubleArray &weights) const
MStatus	setBlendWeights (const MDagPath &path, const MObject &components, const MDoubleArray &weights)
	MFnSkinCluster (const MObject &object, MStatus *ReturnStatus=NULL)
	Constructor.
Protected Member Functions
virtual const char *	className () const
	Class name.

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Constructor & Destructor Documentation

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

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

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

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Member Function Documentation

MFn::Type MFnSkinCluster::type

(

)

const [virtual]

Function set type.

Return the class type : MFn::kSkinClusterFilter

Reimplemented from MFnGeometryFilter.

MStatus MFnSkinCluster::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. 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 MFnSkinCluster::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. 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 MFnSkinCluster::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 MFnSkinCluster::setWeights	(	const MDagPath &	path,
		const MObject &	components,
		unsigned int	influenceIndex,
		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. 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 MFnSkinCluster::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. 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 MFnSkinCluster::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. 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 MFnSkinCluster::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 MFnSkinCluster::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 MFnSkinCluster::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 MFnSkinCluster::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 MFnSkinCluster::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 MFnSkinCluster::setWeights	(	const MDagPath &	path,
		const MObject &	components,
		MIntArray &	influenceIndices,
		MFloatArray &	values,
		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]	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 MFnSkinCluster::getPointsAffectedByInfluence	(	const MDagPath &	path,
		MSelectionList &	result,
		MFloatArray &	weights
	)

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 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 MFnSkinCluster::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 MFnSkinCluster::setBlendWeights	(	const MDagPath &	path,
		const MObject &	components,
		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.