MNodeClass Class Reference

#include <MNodeClass.h>

Class Description

A class for performing node class-level operations in the dependency graph.

MNodeClass allows the manipulation of dependency graph node classes. Operations specific to a particular node should instead use MFnDependencyNode.

Public Member Functions
	MNodeClass (const MString &nodeClassName)
	Construct an MNodeClass object based on the given class name. More...
	MNodeClass (const MTypeId &nodeTypeId)
	Construct an MNodeClass object based on the given MTypeId. More...
MTypeId	typeId () const
	Returns the type id of this node class. More...
MString	typeName () const
	Returns the type name of this node class. More...
MString	classification () const
	Retrieves the classification string for a node class. More...
MStatus	addToClassification (const MString &str)
	Adds to the node class's classification string. More...
MStatus	removeFromClassification (const MString &str)
	Removes an element from the node class's classification string. More...
MString	pluginName (MStatus *ReturnStatus=NULL) const
	Returns the name of the plug-in this node class was defined in. More...
MStatus	addExtensionAttribute (const MObject &attr) const
	Adds an extension attribute to the node class. More...
MStatus	removeExtensionAttribute (const MObject &attr) const
	Removes an extension attribute from the node class. More...
MStatus	removeExtensionAttributeIfUnset (const MObject &attr) const
	Removes an extension attribute from the given dependency node type but only if there are no nodes in the graph with non-default values for this attribute. More...
MStatus	getAttributes (MObjectArray &attr) const
	Get the list of attributes for the node class. More...
unsigned int	attributeCount (MStatus *ReturnStatus=NULL) const
	Get the number of attributes for the node class. More...
MObject	attribute (unsigned int index, MStatus *ReturnStatus=NULL) const
	Finds the attribute of this node class at the given index. More...
MObject	attribute (const MString &attrName, MStatus *ReturnStatus=NULL) const
	Finds the attribute of this node class that has the given name. More...
bool	hasAttribute (const MString &attrName, MStatus *ReturnStatus=NULL) const
	Returns true if the node class already has an attribute with the given name. More...

Static Public Member Functions
static const char *	className ()
	Returns the name of this class. More...

Constructor & Destructor Documentation

MNodeClass

(

const MString &

nodeClassName

)

Construct an MNodeClass object based on the given class name.

If the name cannot be resolved as a known class, the MNodeClass will refer to an MFn::kInvalid api type.

Parameters

[in]

nodeClassName

class name of the node type to wrap

MNodeClass

(

const MTypeId &

nodeTypeId

)

Construct an MNodeClass object based on the given MTypeId.

This can then be used to perform class-level operations.

Parameters

[in]

nodeTypeId

id of the node type to wrap

Member Function Documentation

MTypeId typeId

(

)

const

Returns the type id of this node class.

The type is is the 4 byte code that is used in the binary file format to identify the type of this node.

Returns

The type id of this node

MString typeName

(

)

const

Returns the type name of this node class.

The string returned is the name of the node type as it is used in the ascii file format.

Returns

The type name of this node

MString classification

(

)

const

Retrieves the classification string for a node class.

This is a string that is used in dependency nodes that are also shaders to provide more detailed type information to the rendering system. See the documentation for the MEL commands getClassification and listNodeTypes for information on the strings that can be provided.

User-defined nodes set this value through a parameter to MFnPlugin::registerNode.

Returns

The classification string. If the node class does not have an associated classification, an empty string will be returned.

MStatus addToClassification

(

const MString &

str

)

Adds to the node class's classification string.

See the classification() method, above.

Adding to the classification string is useful in conjunction with the MSwatchRenderRegister API, to override the swatch rendering of built-in Maya node types. Adding the classification 'swatch/File' causes nodes to use a simple default icon instead of their usual swatch rendering.

Parameters

[in]

str

The string to add to the classification

Returns

Status of operation.

Status Codes:

• MS::kSuccess operation successful
• MS::kFailure new classification not added
• MS::kInvalidParameter the string to add was invalid (e.g. contained the separator character (':'))

MStatus removeFromClassification

(

const MString &

str

)

Removes an element from the node class's classification string.

See the classification() method, above.

Parameters

[in]

str

The string to remove from the classification

Returns

Status of operation.

Status Codes:

• MS::kSuccess operation successful
• MS::kFailure classification not removed
• MS::kInvalidParameter the string to remove was invalid (e.g. contained the separator character (':'))

MString pluginName

(

MStatus *

ReturnStatus = NULL

)

const

Returns the name of the plug-in this node class was defined in.

The name returned is the name of the plug-in on disk, and may contain pathname separators (such as `/') and drive letters (e.g. C:).

Parameters

[out]

ReturnStatus

return status

Returns

The name of the plug-in

Status Codes:

• MS::kSuccess operation successful
• MS::kFailure node class was not found in plugin database

MStatus addExtensionAttribute

(

const MObject &

attr

)

const

Adds an extension attribute to the node class.

An extension attribute is a class-level attribute which has been added dynamically to a node class. Because it is added at the class level, all nodes of that class will have the given attribute, and will only store the attribute's value if it differs from the default.

Parameters

[in]

attr

The attribute to add

Returns

Status of operation.

Status Codes:

• MS::kSuccess operation successful
• MS::kFailure extension attribute was not added
• MS::kInvalidParameter this node class was not a valid one for adding extensions

MStatus removeExtensionAttribute

(

const MObject &

attr

)

const

Removes an extension attribute from the node class.

An extension attribute is a class-level attribute which has been added dynamically to a node class. Because it is added at the class level, all nodes of that class will have the given attribute, and will only store the attribute's value if it differs from the default.

Parameters

[in]

attr

The attribute to remove

Returns

Status of operation.

Status Codes:

• MS::kSuccess operation successful
• MS::kFailure extension attribute was not removed
• MS::kInvalidParameter attribute was not an extension on this class

MStatus removeExtensionAttributeIfUnset

(

const MObject &

attr

)

const

Removes an extension attribute from the given dependency node type but only if there are no nodes in the graph with non-default values for this attribute.

An extension attribute is a class-level attribute which has been added dynamically to a node class. Because it is added at the class level, all nodes of that class will have the given attribute. This method will only remove the attribute if any of its node values differs from the default.

Parameters

[in]

attr

The attribute to remove

Returns

Status of operation.

Status Codes:

• MS::kSuccess extension attribute was removed
• MS::kFailure extension attribute was not removed
• MS::kInvalidParameter attribute was not an extension on this class

MStatus getAttributes

(

MObjectArray &

attr

)

const

Get the list of attributes for the node class.

Parameters

[out]

attr

The list of attributes

Returns

Status of operatation

Status Codes:

• MS::kSuccess operation successful
• MS::kFailure unable to complete operation

unsigned int attributeCount

(

MStatus *

ReturnStatus = NULL

)

const

Get the number of attributes for the node class.

Parameters

[out]

ReturnStatus

return status

Returns

The number of attributes.

Status Codes:

• MS::kSuccess operation successful
• MS::kFailure unable to count attributes

MObject attribute	(	unsigned int	index,
		MStatus *	ReturnStatus = NULL
	)		const

Finds the attribute of this node class at the given index.

Index order is based on the order in which the attributes were added to the class.

Parameters

[in]	index	the index of the attribute
[out]	ReturnStatus	return status

Returns

The attribute, or kNullObj if no attribute existed at the given index

Status Codes:

• MS::kSuccess operation successful
• MS::kFailure not a valid node class
• MS::kInvalidParameter index is out of range

MObject attribute	(	const MString &	attrName,
		MStatus *	ReturnStatus = NULL
	)		const

Finds the attribute of this node class that has the given name.

Parameters

[in]	attrName	name of the attribute to find
[out]	ReturnStatus	return status

Returns

The attribute, or kNullObj if no attribute with the given name could be found

Status Codes:

• MS::kSuccess operation successful
• MS::kFailure the search could not be completed

bool hasAttribute	(	const MString &	attrName,
		MStatus *	ReturnStatus = NULL
	)		const

Returns true if the node class already has an attribute with the given name.

Parameters

[in]	attrName	Name of attribute to be checked.
[out]	ReturnStatus	return status

Returns

true if the node class has attribute, false otherwise.

Status Codes:

• MS::kSuccess operation is successful
• MS::kFailure unable to complete operation

const char * className ( )

static

Returns the name of this class.

Returns

Name of this class.

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The documentation for this class was generated from the following files:

• MNodeClass.h
• MNodeClass.cpp