MPlug Class Reference

#include <MPlug.h>

Class Description

Create and Access dependency node plugs.

MPlug provides methods for creating plugs, and accessing the plugs' dependency node and attributes.

A plug is a point on a dependency node where a particular attribute can be connected. In simple cases the plug and attribute are equivalent. When you have array attributes, however, the plug is more specific in that it indicates which of the array elements is to be connected.

There are two main types of plugs: networked plugs and non-networked plugs. Non-networked plugs can be considered user plugs as they are created by users and belong to users. Networked plugs can be considered dependency node plugs as they are part of the dependency graph and can only be referenced by users.

In every dependency node there is a network or "tree" of plugs indicating connections that have been made to attributes of the node. The plugs in this tree are known as networked plugs as they belong to the dependency node's network.

Non-networked plugs are plugs that you can create in order to establish a new connection to an attribute, or to get or set a value on an attribute. When a connection is made using these plugs, a networked version of the plug is created and added to the dependency nodes network.

A networked plug cannot be explicitly created. They are created when a connection is established for some attribute of the node. Since the allocation of networked plugs is managed exclusively by Maya, a plugin should never reference a networked plug after changes are made to the DG. Instead, use a non-networked version of the plug, or get a new reference to the networked plug.

All a non-networked plug knows is how to uniquely describe the attribute that it references, in fact the purpose of a non-networked plug is to specify, without ambiguity, an attribute of a dependency node. A non-networked plug contains an array of array indices that plot the path from the root plug to this plug.

For simple attributes the plug and attribute are equivalent. Compound attributes are also unambiguous. A plug that refers to an array attribute, however, is more complex as it can refer to the array plug or an element plug in the array.

Several methods are provided for navigating the plug tree. The child() method can be used to retrieve the child plugs of a compound plug. The elementByLogicalIndex() and elementByPhysicalIndex() methods can be used to retrieve the element plugs of an array plug. The parent() and array() methods traverse the tree in the opposite direction: parent() retrieves a compound plug from a child plug, and array() retrieves an array plug from an element plug.

Since connections to arrays are sparse, element plugs have both logical and physical indexes. The logical indexes are used by MEL, and are sparse. Physical indexes, on the other hand, are not sparse. It is guaranteed that the physical indexes will range from 0 to numElements() - 1. Using the physical indexes, iterating over the element plugs in an array is easy:

// See note below on numElements() method
for (i = 0; i < arrayPlug.numElements (); i++)
{
    MPlug elementPlug = arrayPlug [i];
    unsigned int logicalIndex = elementPlug.logicalIndex();
    // ...
}

This is equivalent to calling elementByPhysicalIndex() since the bracket operator uses physical indexes.

The ancestry of a plug is the tree above the plug: any parents or arrays which this plug belongs to. The selectAncestorLogicalIndex() method provides quick access to element plugs without walking the plug tree. A plug does not need to exist in the datablock or plug tree in order to be constructed using selectAncestorLogicalIndex(), but once a value is requested or set on the plug, it will be added to the datablock if it was not there already. For example:

MPlug plug(node,attribute);
// See note below on numElements() method
unsigned int count = plug.numElements();
if (0 == count) {
    plug.selectAncestorLogicalIndex(0,attribute);
    plug.setValue(setVal);
    count = plug.numElements(); // count will now be 1 since we added a value

    plug.selectAncestorLogicalIndex(10,attribute);
    MObject getVal;
    plug.getValue(getVal);
    count = plug.numElements(); // count will now be 2 since we asked for a value
}

Once a value has been added to an array plug, it will usually remain in the datablock as long as the scene is open. The exception is for attributes that have their disconnect behavior set to kDelete: data for these attributes will be deleted when their connection is broken. When a file is saved, only array values that are not at their default values will be written out. Therefore, the number of elements in an array plug may change when the file is read in again.

Note

The numElements() call for array plugs returns a value based on the information in the datablock. It is possible to have un-evaluated connected items being excluded from the count since these items are not yet in the datablock. In this case, the numElements() method will return the correct answer if the evaluateNumElements() call is made first. But this cannot be done in the MPxNode::compute() method of a node.

Examples:

Public Types
enum	MValueSelector { kAll, kNonDefault, kChanged, kLastAttrSelector }
	Which values to generate setAttr commands for. More...
enum	FreeToChangeState { kFreeToChange = 0, kNotFreeToChange, kChildrenNotFreeToChange }
	Plug state returned by isFreeToChange. More...

Public Member Functions
	MPlug ()
	Constructor. More...
	MPlug (const MPlug &in)
	Copy constructor. More...
	MPlug (const MObject &node, const MObject &attribute)
	Constructor. More...
virtual	~MPlug ()
	Destructor.
MStatus	setAttribute (MObject &attribute)
	This method is a convenience routine to allow quick movement between attributes on a single node. More...
MObject	attribute (MStatus *ReturnStatus=nullptr) const
	This method returns the attribute that this plug refers to. More...
MObject	node (MStatus *ReturnStatus=nullptr) const
	Returns the dependency node that this plug belongs to. More...
MString	name (MStatus *ReturnStatus=nullptr) const
	Returns the name of this plug in the form 'nodeName.attributeName'. More...
MString	partialName (bool includeNodeName=false, bool includeNonMandatoryIndices=false, bool includeInstancedIndices=false, bool useAlias=false, bool useFullAttributePath=false, bool useLongNames=false, MStatus *ReturnStatus=nullptr) const
	By default, this method returns the shortest possible name for the plug, but its parameters can be used to add parts back in. More...
MStatus	getSetAttrCmds (MStringArray &cmds, MValueSelector valueSelector=kAll, bool useLongNames=false)
	Returns an array of strings containing setAttr commands for this plug and all of its descendent plugs. More...
bool	isNetworked (MStatus *ReturnStatus=nullptr) const
	This method determines if the plug is networked or non-networked. More...
bool	isArray (MStatus *ReturnStatus=nullptr) const
	This method determines if the plug is an array plug. More...
bool	isElement (MStatus *ReturnStatus=nullptr) const
	This method determines if the plug is an element plug. More...
bool	isCompound (MStatus *ReturnStatus=nullptr) const
	This method determines if the plug is a compound plug. More...
bool	isChild (MStatus *ReturnStatus=nullptr) const
	This method determines if the plug is a child plug. More...
bool	isProcedural (MStatus *ReturnStatus=nullptr) const
	This method determines if the plug is a procedural plug. More...
unsigned int	logicalIndex (MStatus *ReturnStatus=nullptr) const
	Returns the logical index of the element this plug refers to. More...
MStatus	selectAncestorLogicalIndex (unsigned int index, const MObject &attribute=MObject::kNullObj)
	This method is a convenience routine to allow quick iteration and construction of plugs with array plugs in their ancestry. More...
unsigned int	getExistingArrayAttributeIndices (MIntArray &indices, MStatus *ReturnStatus=nullptr)
	This method will return a list of the logical indices of the elements in an array attribute that are either connected or have had their value set. More...
unsigned int	numElements (MStatus *ReturnStatus=nullptr) const
	Return the total number of elements in the datablock of this array plug. More...
unsigned int	evaluateNumElements (MStatus *ReturnStatus=nullptr)
	Return the total number of elements in the datablock of this array plug. More...
unsigned int	numChildren (MStatus *ReturnStatus=nullptr) const
	Return the total number of children of this compound plug. More...
unsigned int	numConnectedElements (MStatus *ReturnStatus=nullptr) const
	Return the total number of connected element plugs belonging to this array plug. More...
unsigned int	numConnectedChildren (MStatus *ReturnStatus=nullptr) const
	Return the number of children of this plug that are connected in the dependency graph. More...
MPlug	child (MObject &attr, MStatus *ReturnStatus=nullptr) const
	Returns a plug to a given attribute that is a child of this plug. More...
MPlug	child (unsigned int index, MStatus *ReturnStatus=nullptr) const
	Returns a plug to a given attribute that is a child of this plug. More...
MPlug	parent (MStatus *ReturnStatus=nullptr) const
	Returns the parent plug. More...
MPlug	array (MStatus *ReturnStatus=nullptr) const
	Returns the array to which this element plug belongs. More...
MPlug	elementByLogicalIndex (unsigned int logicalIndex, MStatus *ReturnStatus=nullptr) const
	This method will find and return a plug with the given logical index. More...
MPlug	elementByPhysicalIndex (unsigned int physicalIndex, MStatus *ReturnStatus=nullptr) const
	This method will find and return a plug with the given physical index. More...
MPlug	connectionByPhysicalIndex (unsigned int physicalIndex, MStatus *ReturnStatus=nullptr) const
	This method will find and return a connected plug with the given physical index for its connection. More...
bool	connectedTo (MPlugArray &array, bool asDst, bool asSrc, MStatus *ReturnStatus=nullptr) const
	This method finds all of the plugs that this plug is connected with. More...
bool	isConnected (MStatus *ReturnStatus=nullptr) const
	Determines if this plug is connected to one or more plugs. More...
MPlug	source (MStatus *ReturnStatus=nullptr) const
	If this plug is a destination, return the source plug connected to it. More...
bool	destinations (MPlugArray &theDestinations, MStatus *ReturnStatus=nullptr) const
	If this plug is a source, return the destination plugs connected to it. More...
MPlug	sourceWithConversion (MStatus *ReturnStatus=nullptr) const
	If this plug is a destination, return the source plug connected to it. More...
bool	destinationsWithConversions (MPlugArray &theDestinations, MStatus *ReturnStatus=nullptr) const
	If this plug is a source, return the destination plugs connected to it. More...
bool	isKeyable (MStatus *ReturnStatus=nullptr) const
	Determines if this plug is keyable. More...
MStatus	setKeyable (bool keyable)
	This overrides the default keyability of a plug set with MFnAttribute::setKeyable. More...
bool	isLocked (MStatus *ReturnStatus=nullptr) const
	Determines the locked state of this plug's value. More...
MStatus	setLocked (bool locked)
	Sets the locked state for this plug's value. More...
bool	isChannelBoxFlagSet (MStatus *ReturnStatus=nullptr) const
	Returns true if this plug or its attribute has its channel box flag set. More...
MStatus	setChannelBox (bool channelBox)
	Sets whether this plug is displayed in the channel box. More...
bool	isCachingFlagSet (MStatus *ReturnStatus=nullptr) const
	Returns true if this plug or its attribute has its caching flag set. More...
MStatus	setCaching (bool caching)
	Sets whether this plug is cached internally. More...
bool	isNull (MStatus *ReturnStatus=nullptr) const
	This method determines whether this plug is valid. More...
MString	info (MStatus *ReturnStatus=nullptr) const
	This method returns a string containing the name of the node this plug belongs to and the attributes that the plug refers to. More...
bool	isFromReferencedFile (MStatus *ReturnStatus=nullptr) const
	This method determines whether this plug came from a referenced file. More...
bool	isDynamic (MStatus *ReturnStatus=nullptr) const
	Determines whether the attribute is of dynamic type or not. More...
bool	isIgnoredWhenRendering (MStatus *ReturnStatus=nullptr) const
	Determines whether a connection to the attribute should be ignored during rendering. More...
bool	isDefaultValue (bool forceEval=true, MStatus *ReturnStatus=nullptr) const
	This method determines if the plug value is equivalent to the plug's default value. More...
MPlug::FreeToChangeState	isFreeToChange (bool checkParents=true, bool checkChildren=true, MStatus *ReturnStatus=nullptr) const
	Returns true if the plug's value is allowed to be set directly. More...
MDataHandle	constructHandle (MDataBlock &) const
	This method returns a data handle constructed for this plug. More...
void	destructHandle (MDataHandle &) const
	This method destructs the data handle for this plug.
MObject	asMObject (MStatus *ReturnStatus=nullptr) const
	Retrieve the value in the current evaluation context of the attribute this plug references. More...
MDataHandle	asMDataHandle (MStatus *ReturnStatus=nullptr) const
	Retrieve the value in the current evaluation context of the attribute this plug references. More...
double	asDouble (MStatus *ReturnStatus=nullptr) const
	Retrieve the value in the current evaluation context of the attribute this plug references. More...
float	asFloat (MStatus *ReturnStatus=nullptr) const
	Retrieve the value in the current evaluation context of the attribute this plug references. More...
MInt64	asInt64 (MStatus *ReturnStatus=nullptr) const
	Retrieve the value in the current evaluation context of the attribute this plug references. More...
int	asInt (MStatus *ReturnStatus=nullptr) const
	Retrieve the value in the current evaluation context of the attribute this plug references. More...
short	asShort (MStatus *ReturnStatus=nullptr) const
	Retrieve the value in the current evaluation context of the attribute this plug references. More...
bool	asBool (MStatus *ReturnStatus=nullptr) const
	Retrieve the value in the current evaluation context of the attribute this plug references. More...
MDistance	asMDistance (MStatus *ReturnStatus=nullptr) const
	Retrieve the value in the current evaluation context of the attribute this plug references. More...
MAngle	asMAngle (MStatus *ReturnStatus=nullptr) const
	Retrieve the value in the current evaluation context of the attribute this plug references. More...
MTime	asMTime (MStatus *ReturnStatus=nullptr) const
	Retrieve the value in the current evaluation context of the attribute this plug references. More...
char	asChar (MStatus *ReturnStatus=nullptr) const
	Retrieve the value in the current evaluation context of the attribute this plug references. More...
MString	asString (MStatus *ReturnStatus=nullptr) const
	Retrieve the value in the current evaluation context of the attribute this plug references. More...
MStatus	setMObject (MObject &)
	Set the current value of the attribute this plug references. More...
MStatus	setMPxData (MPxData *)
	Set the current value of the attribute this plug references. More...
MStatus	setMDataHandle (MDataHandle &)
	Set the current value of the attribute this plug references with the values in the handle. More...
MStatus	setDouble (double)
	Set the current value of the attribute this plug references. More...
MStatus	setFloat (float)
	Set the current value of the attribute this plug references. More...
MStatus	setInt64 (MInt64)
	Set the current value of the attribute this plug references. More...
MStatus	setInt (int)
	Set the current value of the attribute this plug references. More...
MStatus	setShort (short)
	Set the current value of the attribute this plug references. More...
MStatus	setBool (bool)
	Set the current value of the attribute this plug references. More...
MStatus	setMDistance (MDistance &)
	Set the current value of the attribute this plug references. More...
MStatus	setMAngle (MAngle &)
	Set the current value of the attribute this plug references. More...
MStatus	setMTime (MTime &)
	Set the current value of the attribute this plug references. More...
MStatus	setChar (char)
	Set the current value of the attribute this plug references. More...
MStatus	setString (const MString &)
	Set the current value of the attribute this plug references. More...
MPlug &	operator= (const MPlug &other)
	Assignment operator. More...
MPlug	operator[] (unsigned int physicalIndex) const
	This method will find and return a plug with the given physical index. More...
bool	operator== (const MPlug &other) const
	Comparison operator for MPlugs. More...
bool	operator== (const MObject &other) const
	Comparison operator for a plug and an attribute. More...
bool	operator!= (const MPlug &other) const
	The inequality operator for MPlugs. More...
bool	operator!= (const MObject &other) const
	The inequality operator for a plug and an attribute. More...
MStatus	setNumElements (unsigned int)
	The method is used to pre-allocate the number of elements that an array plug will contain. More...
bool	isSource (MStatus *ReturnStatus=nullptr) const
	Determines if this plug is connected as a source. More...
bool	isDestination (MStatus *ReturnStatus=nullptr) const
	Determines if this plug is connected as a destination. More...
MStatus	getValue (MObject &) const
	NO SCRIPT SUPPORT. More...
MStatus	getValue (MDataHandle &) const
	NO SCRIPT SUPPORT. More...
MStatus	getValue (double &) const
	NO SCRIPT SUPPORT. More...
MStatus	getValue (float &) const
	NO SCRIPT SUPPORT. More...
MStatus	getValue (MInt64 &) const
	NO SCRIPT SUPPORT. More...
MStatus	getValue (int &) const
	NO SCRIPT SUPPORT. More...
MStatus	getValue (short &) const
	NO SCRIPT SUPPORT. More...
MStatus	getValue (bool &) const
	NO SCRIPT SUPPORT. More...
MStatus	getValue (MDistance &) const
	NO SCRIPT SUPPORT. More...
MStatus	getValue (MAngle &) const
	NO SCRIPT SUPPORT. More...
MStatus	getValue (MTime &) const
	NO SCRIPT SUPPORT. More...
MStatus	getValue (char &) const
	NO SCRIPT SUPPORT. More...
MStatus	getValue (MString &) const
	NO SCRIPT SUPPORT. More...
MStatus	setValue (MObject &)
	NO SCRIPT SUPPORT. More...
MStatus	setValue (MPxData *)
	NO SCRIPT SUPPORT. More...
MStatus	setValue (MDataHandle &)
	NO SCRIPT SUPPORT. More...
MStatus	setValue (double)
	NO SCRIPT SUPPORT. More...
MStatus	setValue (float)
	NO SCRIPT SUPPORT. More...
MStatus	setValue (MInt64)
	NO SCRIPT SUPPORT. More...
MStatus	setValue (int)
	NO SCRIPT SUPPORT. More...
MStatus	setValue (short)
	NO SCRIPT SUPPORT. More...
MStatus	setValue (bool)
	NO SCRIPT SUPPORT. More...
MStatus	setValue (MDistance &)
	NO SCRIPT SUPPORT. More...
MStatus	setValue (MAngle &)
	NO SCRIPT SUPPORT. More...
MStatus	setValue (MTime &)
	NO SCRIPT SUPPORT. More...
MStatus	setValue (char)
	NO SCRIPT SUPPORT. More...
MStatus	setValue (const MString &)
	NO SCRIPT SUPPORT. More...
MStatus	setValue (const char *)
	NO SCRIPT SUPPORT. More...
MPlug	operator[] (MObject &attr) const
	NO SCRIPT SUPPORT. More...
	operator MObject () const
	NO SCRIPT SUPPORT. More...
bool	operator! () const
	NO SCRIPT SUPPORT. More...
MObject	asMObject (const MDGContext &, MStatus *ReturnStatus=nullptr) const
	This method is obsolete. More...
MDataHandle	asMDataHandle (const MDGContext &, MStatus *ReturnStatus=nullptr) const
	This method is obsolete. More...
double	asDouble (const MDGContext &, MStatus *ReturnStatus=nullptr) const
	This method is obsolete. More...
float	asFloat (const MDGContext &, MStatus *ReturnStatus=nullptr) const
	This method is obsolete. More...
MInt64	asInt64 (const MDGContext &, MStatus *ReturnStatus=nullptr) const
	This method is obsolete. More...
int	asInt (const MDGContext &, MStatus *ReturnStatus=nullptr) const
	This method is obsolete. More...
short	asShort (const MDGContext &, MStatus *ReturnStatus=nullptr) const
	This method is obsolete. More...
bool	asBool (const MDGContext &, MStatus *ReturnStatus=nullptr) const
	This method is obsolete. More...
MDistance	asMDistance (const MDGContext &, MStatus *ReturnStatus=nullptr) const
	This method is obsolete. More...
MAngle	asMAngle (const MDGContext &, MStatus *ReturnStatus=nullptr) const
	This method is obsolete. More...
MTime	asMTime (const MDGContext &, MStatus *ReturnStatus=nullptr) const
	This method is obsolete. More...
char	asChar (const MDGContext &, MStatus *ReturnStatus=nullptr) const
	This method is obsolete. More...
MString	asString (const MDGContext &, MStatus *ReturnStatus=nullptr) const
	This method is obsolete. More...
MStatus	getValue (MObject &, MDGContext &) const
	This method is obsolete. More...
MStatus	getValue (MDataHandle &, MDGContext &) const
	This method is obsolete. More...
MStatus	getValue (double &, MDGContext &) const
	This method is obsolete. More...
MStatus	getValue (float &, MDGContext &) const
	This method is obsolete. More...
MStatus	getValue (MInt64 &, MDGContext &) const
	This method is obsolete. More...
MStatus	getValue (int &, MDGContext &) const
	This method is obsolete. More...
MStatus	getValue (short &, MDGContext &) const
	This method is obsolete. More...
MStatus	getValue (bool &, MDGContext &) const
	This method is obsolete. More...
MStatus	getValue (MDistance &, MDGContext &) const
	This method is obsolete. More...
MStatus	getValue (MAngle &, MDGContext &) const
	This method is obsolete. More...
MStatus	getValue (MTime &, MDGContext &) const
	This method is obsolete. More...
MStatus	getValue (char &, MDGContext &) const
	This method is obsolete. More...
MStatus	getValue (MString &, MDGContext &) const
	This method is obsolete. More...

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

Member Enumeration Documentation

enum MValueSelector

Which values to generate setAttr commands for.

Enumerator
kAll	All values.
kNonDefault	Non default values.
kChanged	Changed values.
kLastAttrSelector	Last value, for counting.

enum FreeToChangeState

Plug state returned by isFreeToChange.

Enumerator
kFreeToChange	All tested plugs are free to change.
kNotFreeToChange	Some of the tested plugs are not free to change.
kChildrenNotFreeToChange	Some of the children are not free to change.

Constructor & Destructor Documentation

OPENMAYA_MAJOR_NAMESPACE_OPEN MPlug

(

)

Constructor.

Creates an empty plug.

MPlug

(

const MPlug &

other

)

Copy constructor.

Duplicates the given plug.

Parameters

[in]

other

Plug to be copied.

MPlug	(	const MObject &	node,
		const MObject &	attribute
	)

Constructor.

Creates a new plug for the specified attribute and dependency node.

The new plug can be used to establish or remove a connection to the attribute it references. The plug can also be used to query or set the value of the attribute.

This constructor will only create non-networked plugs. A networked version of this plug is automatically created and added to the dependency node's network when a connection to this plug is established.

Parameters

[in]	node	the dependency node this plug belongs to
[in]	attribute	the attribute this plug refers to

Member Function Documentation

MStatus setAttribute

(

MObject &

attribute

)

This method is a convenience routine to allow quick movement between attributes on a single node.

If the current plug is a networked plug, it becomes a new non-networked plug referring to the requested attribute. If the current plug is a non-networked plug, it is changed to refer to the requested attribute.

The passed attribute must be the attribute of a plug on the current node.

Parameters

[in]

attribute

attribute to change the plug to

Returns

Status code

Status Codes:

• MS::kSuccess Operating succeeded
• MS::kFailure Object error

Examples:

MObject attribute

(

MStatus *

ReturnStatus = nullptr

)

const

This method returns the attribute that this plug refers to.

Parameters

[out]

ReturnStatus

Status Code

Returns

The attribute that this plug refers to.

Status Codes:

• MS::kSuccess The attribute was successfully returned.
• MS::kFailure Object error.

Examples:

MObject node

(

MStatus *

ReturnStatus = nullptr

)

const

Returns the dependency node that this plug belongs to.

Parameters

[out]

ReturnStatus

Status Code

Returns

A pointer to this plug's dependency node.

Status Codes:

• MS::kSuccess The dependency node was successfully returned
• MS::kFailure Object error

Examples:

MString name

(

MStatus *

ReturnStatus = nullptr

)

const

Returns the name of this plug in the form 'nodeName.attributeName'.

Parameters

[out]

ReturnStatus

return status

Returns

The name of this node

Status Codes:

• MS::kSuccess operation successful
• MS::kFailure plug is not valid

Examples:

MString partialName	(	bool	includeNodeName = false,
		bool	includeNonMandatoryIndices = false,
		bool	includeInstancedIndices = false,
		bool	useAlias = false,
		bool	useFullAttributePath = false,
		bool	useLongNames = false,
		MStatus *	ReturnStatus = nullptr
	)		const

By default, this method returns the shortest possible name for the plug, but its parameters can be used to add parts back in.

Parameters

[in]	includeNodeName	If true, then the plug's node name is prefixed to the name of the plug, with a dot separating it from the attribute name. If false, then just the attribute name is returned. (default: false)
[in]	includeNonMandatoryIndices	If the plug's attribute is a non-instanced element of a multi which is NOT marked as indexMatters, then setting this parameter true will cause its index to be included in the returned string anyway. If the attribute is marked as indexMatters then its array index will be included regardless of the setting of this parameter. If the attribute is instanced then it is not affected by this parameter. See the next parameter instead. (default: false)
[in]	includeInstancedIndices	If the plug's attribute is an element of an instanced multi, then setting this parameter true will cause the array index to be included in the returned string. For example, if you are planning to append the returned plug name to a node's dagPath, then the instance index is unnecessary as it can be determined from the dagPath. (default: false)
[in]	useFullAttributePath	Normally, the plug's attribute path is compressed so that any compound ancestors which do not serve to uniquely identify the plug are removed. Setting this parameter true will cause the full attribute path to be used. (default: false)
[in]	useAlias	Display aliased name if alias exists. (default: false)
[in]	useLongNames	Normally, short attribute names are used. Setting this true will cause long names to be used. (default: false)
[out]	ReturnStatus	Return status.

Returns

The name of the plug.

Status Codes:

• MS::kSuccess operation successful
• MS::kFailure function set does not have a valid node

Examples:

MStatus getSetAttrCmds	(	MStringArray &	cmds,
		MPlug::MValueSelector	valueSelector = kAll,
		bool	useLongNames = false
	)

Returns an array of strings containing setAttr commands for this plug and all of its descendent plugs.

Parameters

[out]	cmds	Array of strings in which the setAttr commands are to be returned.
[in]	valueSelector	kAll - return setAttr commands for the plug and its children, regardless of their values. kNonDefault - only return setAttr commands for the plug or its children if they are not at their default values. kChanged - for nodes from referenced files, setAttr commands are only returned if the plug or one of its children has changed since its file was loaded. For all other nodes, the behaviour is the same a kNonDefault. Note that if the plug is compound and one of its children has changed, then setAttrs will be generated for *all* of its children, even those which have not changed. (default: kAll)
[in]	useLongNames	Normally, the returned commands will use the short names for flags and attributes. If this parameter is true then their long names will be used instead. (default: false)

Returns

Status code

Status Codes:

• MS::kSuccess operation successful
• MS::kFailure function set does not have a valid node

bool isNetworked

(

MStatus *

ReturnStatus = nullptr

)

const

This method determines if the plug is networked or non-networked.

Networked plugs are part of a dependency node network and define points where connections have been made to the nodes attributes.

Non-networked plugs are user created plugs that are used to refer to an attribute of a node so that it can be connected. If the attribute that the plug refers to has been connected then there will also be a corresponding networked plug.

Parameters

[out]

ReturnStatus

Status Code

Returns

• true
• false

Status Codes:

• MS::kSuccess The operation succeeded.
• MS::kFailure Object error.

bool isArray

(

MStatus *

ReturnStatus = nullptr

)

const

This method determines if the plug is an array plug.

Array plugs refer to array attributes and contain element plugs.

Parameters

[out]

ReturnStatus

Status Code

Returns

• true
• false

Status Codes:

• MS::kSuccess The operation succeeded.
• MS::kFailure Object error.

Examples:

bool isElement

(

MStatus *

ReturnStatus = nullptr

)

const

This method determines if the plug is an element plug.

Element plugs refer to array attributes and are members of array plugs.

Parameters

[out]

ReturnStatus

Status Code

Returns

• true
• false

Status Codes:

• MS::kSuccess The operation succeeded.
• MS::kFailure Object error.

Examples:

bool isCompound

(

MStatus *

ReturnStatus = nullptr

)

const

This method determines if the plug is a compound plug.

Compound plugs refer to compound attributes and have child plugs.

Parameters

[out]

ReturnStatus

Status Code

Returns

• true
• false

Status Codes:

• MS::kSuccess The operation succeeded.
• MS::kFailure Object error.

Examples:

bool isChild

(

MStatus *

ReturnStatus = nullptr

)

const

This method determines if the plug is a child plug.

A child plug's parent is always a compound plug.

Parameters

[out]

ReturnStatus

Status Code

Returns

• true
• false

Status Codes:

• MS::kSuccess The operation succeeded.
• MS::kFailure Object error.

Examples:

bool isProcedural

(

MStatus *

ReturnStatus = nullptr

)

const

This method determines if the plug is a procedural plug.

A procedural plug is one which is created by Maya's internal procedures or by the nodes themselves and which should not be saved to or restored from files.

Parameters

[out]

ReturnStatus

Status Code

Returns

• true
• false

Status Codes:

• MS::kSuccess The operation succeeded.
• MS::kFailure Object error.

Examples:

unsigned int logicalIndex

(

MStatus *

ReturnStatus = nullptr

)

const

Returns the logical index of the element this plug refers to.

The logical index is a sparse index, equivalent to the array index used in MEL.

This plug must be an element plug, and may be either networked or non-networked.

Parameters

[out]

ReturnStatus

Status Code

Returns

The logical array index of the element this plug refers to

Status Codes:

• MS::kSuccess The operation succeeded
• MS::kFailure Object error - no plug
• MS::kInvalidDataType This plug is not an element plug

Examples:

MStatus selectAncestorLogicalIndex	(	unsigned int	index,
		const MObject &	attribute = MObject::kNullObj
	)

This method is a convenience routine to allow quick iteration and construction of plugs with array plugs in their ancestry.

It selects a plug into the current object by changing an ancestor array's logical index.

The passed attribute must be either the attribute of the current plug, or the attribute of an ancestor's plug. It must be an array attribute. By default, it refers to the attribute of the current plug.

If the passed attribute is the attribute of this plug, then this plug will change to refer to its indexth element plug.

For example, consider the following attribute tree. The topmost attribute is a compound attribute "in". It consists of two children: an enum attribute "operation" and a typed attribute "value". Both "value" and "in" are array attributes. To iterate through all of the values, you could write a loop like this:

MPlug inPlug (node, inAttribute);
MPlug valuePlug (node, valueAttribute);
MPlug plug (node, valueAttribute);
for (i = 0; i < inPlug.numElements (); i++)
{
    valuePlug.selectAncestorLogicalIndex (i, inAttribute);
    (for j = 0; j < valuePlug.numElements (); j++)
    {
        plug.selectAncestorLogicalIndex (i, inAttribute);
        plug.selectAncestorLogicalIndex (j, valueAttribute);
        // ...
    }
}

This method is only valid for non-networked plugs since networked plugs are part of a dependency node and can only be modified by making or breaking connections.

Parameters

[in]	index	index value to be set
[in]	attribute	array attribute whose index will be changed

Returns

Status code

Status Codes:

• MS::kSuccess Operation succeeded
• MS::kFailure Object error or networked plug

Examples:

unsigned int getExistingArrayAttributeIndices	(	MIntArray &	indices,
		MStatus *	ReturnStatus = nullptr
	)

This method will return a list of the logical indices of the elements in an array attribute that are either connected or have had their value set.

This method is useful when the logical indices of connected/set elements are sparse.

Parameters

[in]	indices	A list to store the logical indices of the set/connected elements.
[out]	ReturnStatus	Status Code

Returns

The number of set/connected elements

Status Codes:

• MS::kSuccess The indices were successfully obtained.
• MS::kFailure Object error.

unsigned int numElements

(

MStatus *

ReturnStatus = nullptr

)

const

Return the total number of elements in the datablock of this array plug.

The return count will include all existing non-connected elements plus connected elements if they have been evaluated. It will not include connected elements that have not yet been placed into the datablock. The method MPlug::evaluateNumElements can be used in the sitution where you want an accurate count that includes all connected elements.

This method is only valid for array plugs, as no other plugs have elements.

Parameters

[out]

ReturnStatus

Status Code

Returns

Total number of elements

Status Codes:

• MS::kSuccess The count was successfully returned
• MS::kFailure The plug is not an array plug or does not contain a valid node or attribute

Examples:

unsigned int evaluateNumElements

(

MStatus *

ReturnStatus = nullptr

)

Return the total number of elements in the datablock of this array plug.

The return count will include both connected and non-connected elements, and will perform an evaluate in order to make sure that the datablock is as up-to-date as possible since some nodes do not place array elements into the datablock until the attribute is evaluated.

Because this method performs an evaluate, it should not be called from within the compute of a node. Instead, if you want to know the number of elements in an array plug while in a compute, use either MDataBlock::inputArrayValue or MDataBlock::outputArrayValue because they are more efficient and will not result in recursion.

This method is only valid for array plugs, as no other plugs have elements.

Parameters

[out]

ReturnStatus

Status Code

Returns

Total number of elements

Status Codes:

• MS::kSuccess The count was successfully returned
• MS::kFailure The plug is not an array plug or does not contain a valid node or attribute

unsigned int numChildren

(

MStatus *

ReturnStatus = nullptr

)

const

Return the total number of children of this compound plug.

This method is only valid for networked plugs as non-networked plugs contain no information about their children. If this plug is non-networked then a networked version of the plug will be used. If a networked plug does not exist then 0 will be returned.

This method is also only valid for compound plugs or the root plug, since no other plugs have children.

Parameters

[out]

ReturnStatus

Status Code

Returns

Total number of children

Status Codes:

• MS::kSuccess The count was successfully returned
• MS::kFailure Object error

Examples:

unsigned int numConnectedElements

(

MStatus *

ReturnStatus = nullptr

)

const

Return the total number of connected element plugs belonging to this array plug.

This method is only valid for networked plugs as non-networked plugs contain no information about their children. If this plug is non-networked then a networked version of the plug will be used. If a networked plug does not exist then 0 will be returned.

This method is also only valid for array plugs, as no other plugs have elements.

Parameters

[out]

ReturnStatus

Status Code

Returns

Total number of elements

Status Codes:

• MS::kSuccess The count was successfully returned
• MS::kFailure Object error

Examples:

unsigned int numConnectedChildren

(

MStatus *

ReturnStatus = nullptr

)

const

Return the number of children of this plug that are connected in the dependency graph.

This method is only valid for networked plugs as non-networked plugs contain no information about their children. If this plug is non-networked then a networked version of the plug will be used. If a networked plug does not exist then 0 will be returned.

This method is only valid for compound plugs, since no other plugs have children.

Parameters

[out]

ReturnStatus

Status Code

Returns

Total number of children

Status Codes:

• MS::kSuccess The count was successfully returned
• MS::kFailure Object error
• MS::kInvalidDataType This is not a compound plug

Examples:

MPlug child	(	MObject &	obj,
		MStatus *	ReturnStatus = nullptr
	)		const

Returns a plug to a given attribute that is a child of this plug.

This method is only valid for compound plugs.

Parameters

[in]	obj	The child attribute.
[out]	ReturnStatus	Status code.

Returns

The child plug

Status Codes:

• MS::kSuccess Child successfully returned
• MS::kInvalidParameter The given attribute is not a child of this plug
• MS::kInvalidDataType This is not a compound plug
• MS::kFailure Object error or the given attribute is nullptr

Examples:

MPlug child	(	unsigned int	index,
		MStatus *	ReturnStatus = nullptr
	)		const

Returns a plug to a given attribute that is a child of this plug.

This method is only valid for compound plugs.

Parameters

[in]	index	The index of the plug to be found
[out]	ReturnStatus	Status code.

Returns

The child plug

Status Codes:

• MS::kSuccess Child successfully returned
• MS::kInvalidParameter The given attribute is not a child of this plug
• MS::kInvalidDataType This is not a compound plug
• MS::kFailure Object error or the given attribute is nullptr

MPlug parent

(

MStatus *

ReturnStatus = nullptr

)

const

Returns the parent plug.

The parent plug will always be a compound plug. This method is only valid for networked child plugs.

Parameters

[in]

ReturnStatus

Status Code

Returns

The parent of this plug.

Status Codes:

• MS::kSuccess The parent was successfully returned
• MS::kFailure Object error

Examples:

MPlug array

(

MStatus *

ReturnStatus = nullptr

)

const

Returns the array to which this element plug belongs.

This method is only valid for networked element plugs.

Parameters

[out]

ReturnStatus

Status Code

Returns

The array of this plug.

Status Codes:

• MS::kSuccess The array was successfully returned
• MS::kFailure Object error

MPlug elementByLogicalIndex	(	unsigned int	index,
		MStatus *	ReturnStatus = nullptr
	)		const

This method will find and return a plug with the given logical index.

The logical index is the sparse array index used in MEL scripts. If a plug does not exist at the given Index, Maya will create a plug at that index. This is not the case with elementByPhysicalIndex(). If needed, elementByLogicalIndex can be used to expand an array plug on a node. It is important to note that Maya assumes that all such plugs serve a purpose and it will not free non-networked plugs that result from such an array expansion.

The returned plug may or may not be connected.

Parameters

[in]	index	The index of the plug to be found
[out]	ReturnStatus	Status Code

Returns

A plug with the given index

Status Codes:

• MS::kSuccess a plug for the given index was successfully returned
• MS::kFailure Could not get a plug for the given index

Examples:

MPlug elementByPhysicalIndex	(	unsigned int	index,
		MStatus *	ReturnStatus = nullptr
	)		const

This method will find and return a plug with the given physical index.

The index can range from 0 to numElements() - 1. This function is particularly useful for iteration through the element plugs of an array plug. It is equivalent to operator [] (int) This method is only valid for array plugs.

If the returned plug is networked, the networked plug will be returned. Otherwise, a non-networked plug will be returned.

Parameters

[in]	index	The physical array index of the plug to be found
[out]	ReturnStatus	Status Code

Returns

A plug with the given index

Status Codes:

• MS::kSuccess a plug for the given index was successfully returned
• MS::kFailure Could not get a plug for the given index

Examples:

MPlug connectionByPhysicalIndex	(	unsigned int	index,
		MStatus *	ReturnStatus = nullptr
	)		const

This method will find and return a connected plug with the given physical index for its connection.

The index can range from 0 to numConnectedElements() - 1. This method varies from elementByPhysicalIndex in that elementByPhysicalIndex will return plugs pointing to all existing data in the datablock regardless of whether the plug is connected or not.

This method is only valid for array plugs.

Parameters

[in]	index	The physical array index of the plug to be found
[out]	ReturnStatus	Status Code

Returns

A plug with the given index

Status Codes:

• MS::kSuccess a plug for the given index was successfully returned
• MS::kFailure Could not get a plug for the given index

Examples:

bool connectedTo	(	MPlugArray &	array,
		bool	asDst,
		bool	asSrc,
		MStatus *	ReturnStatus = nullptr
	)		const

This method finds all of the plugs that this plug is connected with.

This method will always produce the networked version of the connected plugs.

NOTE: When asDst=true you are asking for a plug connecting in to this one i.e. a source plug that is driving this plug's value. There will only be one of these, or none.

NOTE: When asSrc=true you are asking for all plugs connecting out from this one i.e. destination plugs whose values are driven by this one. There can be any arbitrary number of these and order is not guaranteed so if you look for a specific output/destination plug be sure to check all of them.

It is generally not a good idea to ask for both at the same time since you won't know which are sources or destinations without checking. If you are only interested in the existence of a connection not the actual plug(s) to which this one is connected then use the appropriate connection check methods: isSource()/isDestination()/isConnected().

Calling this method with both asDst and asSrc set to false will do nothing.

Parameters

[in]	array	Location for storing connected plugs (allocated by the caller)
[in]	asDst	Check connections with this plug as destination. If there are such connections, put them in array.
[in]	asSrc	Check connections with this plug as source. If there are such connections, put them in array.
[out]	ReturnStatus	Status Code

Returns

• true If the plug has connections as either source or destination. Note that the array is filled in only with the type of connecting plugs requested by asSrc and asDst. Therefore, the method could return true while the array has nothing in it if, for example, the plug has connections as source but the user passes asSrc = false to the method. The parameters asSrc and asDst have no effect on the boolean return value.
• false If this plug has no connections

Status Codes:

• MS::kSuccess Method returned successfully
• MS::kFailure Object error

Examples:

bool isConnected

(

MStatus *

ReturnStatus = nullptr

)

const

Determines if this plug is connected to one or more plugs.

Parameters

[out]

ReturnStatus

Status Code

Returns

• true If this plug is connected to another plug
• false If this plug is not connected to another plug

Status Codes:

• MS::kSuccess Method returned successfully
• MS::kFailure Object error

Examples:

MPlug source

(

MStatus *

ReturnStatus = nullptr

)

const

If this plug is a destination, return the source plug connected to it.

If this plug is not a destination, a null plug is returned.

This method will produce the networked version of the connected plug.

Parameters

[out]

ReturnStatus

Status Code

Returns

Source plug, or null plug if not a destination.

Status Codes:

• MS::kSuccess Method returned successfully
• MS::kFailure Object error (not attached to a Maya object)

Examples:

bool destinations	(	MPlugArray &	theDestinations,
		MStatus *	ReturnStatus = nullptr
	)		const

If this plug is a source, return the destination plugs connected to it.

If this plug is not a source, a null plug is returned.

This method will produce the networked version of the connected plug.

Parameters

[in]	theDestinations	Location for storing connected plugs (allocated by the caller). The array is first cleared, then the destination plugs are added.
[out]	ReturnStatus	Status Code

Returns

Returns true if the plug has one or more destinations.

Status Codes:

• MS::kSuccess Method returned successfully
• MS::kFailure Object error (not attached to a Maya object)

MPlug sourceWithConversion

(

MStatus *

ReturnStatus = nullptr

)

const

If this plug is a destination, return the source plug connected to it.

This method is very similar to the source() method. The only difference is that the source() method skips over any unit conversion node connected to this destination, and returns the source of the unit conversion node.

sourceWithConversion() does not skip over unit conversion nodes, and returns the source plug on a unit conversion node, if present.

Note that the behavior of connectedTo() is identical to sourceWithConversion(), that is, do not skip over unit conversion nodes.

Parameters

[out]

ReturnStatus

Status Code

Returns

Source plug, or null plug if not a destination.

Status Codes:

• MS::kSuccess Method returned successfully
• MS::kFailure Object error (not attached to a Maya object)

bool destinationsWithConversions	(	MPlugArray &	theDestinations,
		MStatus *	ReturnStatus = nullptr
	)		const

If this plug is a source, return the destination plugs connected to it.

This method is very similar to the destinations() method. The only difference is that the destinations() method skips over any unit conversion node connected to this source, and returns the destination of the unit conversion node.

destinationsWithConversions() does not skip over unit conversion nodes, and returns the destination plug on a unit conversion node, if present.

Note that the behavior of connectedTo() is identical to destinationsWithConversions(), that is, do not skip over unit conversion nodes.

Parameters

[in]	theDestinations	Location for storing connected plugs (allocated by the caller). The array is first cleared, then the destination plugs are added.
[out]	ReturnStatus	Status Code

Returns

Returns true if the plug has one or more destinations.

Status Codes:

• MS::kSuccess Method returned successfully
• MS::kFailure Object error (not attached to a Maya object)

bool isKeyable

(

MStatus *

ReturnStatus = nullptr

)

const

Determines if this plug is keyable.

The default keyability of a plug is determined by its attribute, and can be retrieved using MFnAttribute::isKeyable. Keyable plugs will be keyed by AutoKey and the Set Keyframe UI. Non-keyable plugs prevent the user from setting keys via the obvious UI provided for keying. Being non-keyable is not a hard block against adding keys to an attribute.

Parameters

[out]

ReturnStatus

Status Code

Returns

• true If this plug is keyable
• false If this plug is not keyable

Status Codes:

• MS::kSuccess Successful completion
• MS::kFailure Object error

MStatus setKeyable

(

bool

keyable

)

This overrides the default keyability of a plug set with MFnAttribute::setKeyable.

Keyable plugs will be keyed by AutoKey and the Set Keyframe UI. Non-keyable plugs prevent the user from setting keys via the obvious UI provided for keying. Being non-keyable is not a hard block against adding keys to an attribute.

Parameters

[in]

keyable

True if this plug should be keyable

Returns

Status code

Status Codes:

• MS::kSuccess Successful completion
• MS::kFailure Object error

bool isLocked

(

MStatus *

ReturnStatus = nullptr

)

const

Determines the locked state of this plug's value.

A plug's locked state determines whether or not the plug's value can be changed.

Parameters

[out]

ReturnStatus

Status Code

Returns

• true If this plug's value is locked
• false If this plug's value is not locked

Status Codes:

• MS::kSuccess Successful completion
• MS::kFailure Object error

Examples:

MStatus setLocked

(

bool

locked

)

Sets the locked state for this plug's value.

A plug's locked state determines whether or not the plug's value can be changed.

Parameters

[in]

locked

True if this plug's value is to be locked

Returns

Status code

Status Codes:

• MS::kSuccess Successful completion
• MS::kFailure Object error

bool isChannelBoxFlagSet

(

MStatus *

ReturnStatus = nullptr

)

const

Returns true if this plug or its attribute has its channel box flag set.

Attributes will appear in the channel box if their channel box flag is set or if they are keyable.

Parameters

[out]

ReturnStatus

Status Code

Returns

• true channel box flag has been set
• false channel box flag has not been set

Status Codes:

• MS::kSuccess Successful completion
• MS::kFailure Object error

MStatus setChannelBox

(

bool

inChannelBox

)

Sets whether this plug is displayed in the channel box.

This overrides the default display of a plug set with MFnAttribute::setChannelBox. Keyable attributes are always shown in the channel box so this flag is ignored on keyable plugs.

Parameters

[in]

inChannelBox

True if this plug should be displayed in the channel box

Returns

Status code

Status Codes:

• MS::kSuccess Successful completion
• MS::kFailure Object error

bool isCachingFlagSet

(

MStatus *

ReturnStatus = nullptr

)

const

Returns true if this plug or its attribute has its caching flag set.

Parameters

[out]

ReturnStatus

Status Code

Returns

• true caching flag has been set
• false caching flag has not been set

Status Codes:

• MS::kSuccess Successful completion
• MS::kFailure Object error

MStatus setCaching

(

bool

isCaching

)

Sets whether this plug is cached internally.

Note: turning caching on for a plug will force the plug to become networked. Network plugs take longer to look up in the DG; therefore you should only make a plug cached only if you are certain that the network plug look-up will take less than the saved evaluation cost.

Not all plugs can be made cached (or un-cached). If the attribute is defined to be cached, then you cannot uncache the attribute. As well, you cannot define caching on element plugs.

Parameters

[in]

isCaching

True if this plug should be cached

Returns

Status code

Status Codes:

• MS::kSuccess Successful completion
• MS::kFailure Object error
• MS::kInvalidDataType Plug is a multi or plug is marked permanently cached.

bool isNull

(

MStatus *

ReturnStatus = nullptr

)

const

This method determines whether this plug is valid.

A plug is valid if it refers to an attribute.

Parameters

[out]

ReturnStatus

Status Code

Returns

• true this plug is not valid
• false this plug is valid

Status Codes:

• MS::kSuccess This method was successful
• MS::kFailure Object error

Examples:

MString info

(

MStatus *

ReturnStatus = nullptr

)

const

This method returns a string containing the name of the node this plug belongs to and the attributes that the plug refers to.

The string is of the form dependNode:atr1.atr2[].attr3 ...

This method is useful for debugging purposes.

Parameters

[out]

ReturnStatus

Status Code

Returns

Returns a string containing dependency node and attribute information for this plug.

Status Codes:

• MS::kSuccess The string was successfully generated
• MS::kFailure Object error

Examples:

bool isFromReferencedFile

(

MStatus *

ReturnStatus = nullptr

)

const

This method determines whether this plug came from a referenced file.

A plug is considered to have come from a referenced file if it is connected and that connection was made within a referenced file.

Parameters

[out]

ReturnStatus

Status Code

Returns

• true plug was created within a referenced file
• false plug was created within the current scene

Status Codes:

• MS::kSuccess This method was successful
• MS::kFailure Object error

Examples:

bool isDynamic

(

MStatus *

ReturnStatus = nullptr

)

const

Determines whether the attribute is of dynamic type or not.

Parameters

[out]

ReturnStatus

Status Code

Returns

• true If the attribute is dynamic
• false If this attribute is not added by user.

Status Codes:

• MS::kSuccess Successful completion
• MS::kFailure Object error

bool isIgnoredWhenRendering

(

MStatus *

ReturnStatus = nullptr

)

const

Determines whether a connection to the attribute should be ignored during rendering.

Parameters

[out]

ReturnStatus

Status Code

Returns

• true If connected, the attribute should be ingored during rendering.
• false If connected, the attribute should not be ingored during rendering.

Status Codes:

• MS::kSuccess Successful completion
• MS::kFailure Object error

bool isDefaultValue	(	bool	forceEval = true,
		MStatus *	ReturnStatus = nullptr
	)		const

This method determines if the plug value is equivalent to the plug's default value.

Optionally, disable evaluation of the plug before testing its value against the plug's default value. Disabling this option represents a performance optimization in cases where the plug's value is known to be valid and correct.

Parameters

[in]	forceEval	Evaluate the plug prior to test.
[out]	ReturnStatus	Status Code

Status Codes:

• MS::kSuccess The operation succeeded.
• MS::kFailure Object error.

MPlug::FreeToChangeState isFreeToChange	(	bool	checkParents = true,
		bool	checkChildren = true,
		MStatus *	ReturnStatus = nullptr
	)		const

Returns true if the plug's value is allowed to be set directly.

A plug isFreeToChange if it is not locked, and it is not a destination or if it is a destination, then it must be a special case (such as connected to an anim curve).

Normally this is not something that needs to be checked, since the DG or MEL operations take care of this for you.

If the parents are not free to change, then the children will not be free to change. However if the parents are free to change, some children may not be free to change.

Parameters

[in]	checkParents	Check parent plugs.
[in]	checkChildren	Check child plugs.
[out]	ReturnStatus	Status Code

Returns

• kFreeToChange All tested plugs are free to change.
• kNotFreeToChange Some of the tested plugs are not free to change.
• kChildrenNotFreeToChange Some of the children are not free to change.

Status Codes:

• MS::kSuccess Successful completion
• MS::kFailure Object error

Examples:

MDataHandle constructHandle

(

MDataBlock &

mBlock

)

const

This method returns a data handle constructed for this plug.

Returns

MDataHandle for this plug

MObject asMObject

(

MStatus *

ReturnStatus = nullptr

)

const

Retrieve the value in the current evaluation context of the attribute this plug references.

This method returns a copy of the attribute value for the plug and not a reference. The setObject method of this class can be used to modify the plug's value.

Parameters

[out]

ReturnStatus

Status Code

Returns

Value of plug as an MObject

Status Codes:

• MS::kSuccess Value exists and is non-null, and contains the correct information
• MS::kFailure Either the value is a nullptr value (kFailure) or the value does not exist (kObjectDoesNotExist failure)

Examples:

MDataHandle asMDataHandle

(

MStatus *

ReturnStatus = nullptr

)

const

Retrieve the value in the current evaluation context of the attribute this plug references.

This method is useful when wanting to retrieve an entire set of values from an array plug with a single call. An MArrayDataHandle can then be constructed from the returned MDataHandle to access the array data values.

Parameters

[out]

ReturnStatus

Status Code

Returns

Value of plug as an MDataHandle. When done using the returned handle, the caller must destroy it using MPlug::destructHandle().

Status Codes:

• MS::kSuccess
• MS::kFailure

Examples:

double asDouble

(

MStatus *

ReturnStatus = nullptr

)

const

Retrieve the value in the current evaluation context of the attribute this plug references.

Parameters

[out]

ReturnStatus

Status Code

Returns

Value of plug as a double

Status Codes:

• MS::kSuccess
• MS::kFailure

Examples:

float asFloat

(

MStatus *

ReturnStatus = nullptr

)

const

Retrieve the value in the current evaluation context of the attribute this plug references.

Parameters

[out]

ReturnStatus

Status Code

Returns

Value of plug as a float

Status Codes:

• MS::kSuccess
• MS::kFailure

Examples:

MInt64 asInt64

(

MStatus *

ReturnStatus = nullptr

)

const

Retrieve the value in the current evaluation context of the attribute this plug references.

Parameters

[out]

ReturnStatus

Status Code

Returns

Value of plug as an int

Status Codes:

• MS::kSuccess
• MS::kFailure

int asInt

(

MStatus *

ReturnStatus = nullptr

)

const

Retrieve the value in the current evaluation context of the attribute this plug references.

Parameters

[out]

ReturnStatus

Status Code

Returns

Value of plug as an int

Status Codes:

• MS::kSuccess
• MS::kFailure

Examples:

short asShort

(

MStatus *

ReturnStatus = nullptr

)

const

Retrieve the value in the current evaluation context of the attribute this plug references.

Parameters

[out]

ReturnStatus

Status Code

Returns

Value of plug as a short

Status Codes:

• MS::kSuccess
• MS::kFailure

Examples:

bool asBool

(

MStatus *

ReturnStatus = nullptr

)

const

Retrieve the value in the current evaluation context of the attribute this plug references.

Parameters

[out]

ReturnStatus

Status Code

Returns

Value of plug as a bool

Status Codes:

• MS::kSuccess
• MS::kFailure

Examples:

MDistance asMDistance

(

MStatus *

ReturnStatus = nullptr

)

const

Retrieve the value in the current evaluation context of the attribute this plug references.

Parameters

[out]

ReturnStatus

Status Code

Returns

Value of plug as an MDistance

Status Codes:

• MS::kSuccess
• MS::kFailure

MAngle asMAngle

(

MStatus *

ReturnStatus = nullptr

)

const

Retrieve the value in the current evaluation context of the attribute this plug references.

Parameters

[out]

ReturnStatus

Status Code

Returns

Value of plug as an MAngle

Status Codes:

• MS::kSuccess
• MS::kFailure

MTime asMTime

(

MStatus *

ReturnStatus = nullptr

)

const

Retrieve the value in the current evaluation context of the attribute this plug references.

Parameters

[out]

ReturnStatus

Status Code

Returns

Value of plug as an MTime

Status Codes:

• MS::kSuccess
• MS::kFailure

char asChar

(

MStatus *

ReturnStatus = nullptr

)

const

Retrieve the value in the current evaluation context of the attribute this plug references.

Parameters

[in]

ReturnStatus

Status Code

Returns

Value of plug as a char

Status Codes:

• MS::kSuccess
• MS::kFailure

Examples:

MString asString

(

MStatus *

ReturnStatus = nullptr

)

const

Retrieve the value in the current evaluation context of the attribute this plug references.

Parameters

[out]

ReturnStatus

Status Code

Returns

Value of plug as an MString

Status Codes:

• MS::kSuccess
• MS::kFailure Object error or internal failure

Examples:

MStatus setMObject

(

MObject &

val

)

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

MStatus setMPxData

(

MPxData *

val

)

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

MStatus setMDataHandle

(

MDataHandle &

handle

)

Set the current value of the attribute this plug references with the values in the handle.

This method is most useful when the plug is an array plug, and you've filled the handle with data. Sending the value using this version of setValue will set the handle's data into the datablock and send out the appropriate attributeChanged messages to update the UI related to the attribute.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Parameters

[in]

handle

The handle containing the data to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

MStatus setDouble

(

double

val

)

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

Examples:

MStatus setFloat

(

float

val

)

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

Examples:

MStatus setInt64

(

MInt64

val

)

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

MStatus setInt

(

int

val

)

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

Examples:

MStatus setShort

(

short

val

)

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

Examples:

MStatus setBool

(

bool

val

)

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

Examples:

MStatus setMDistance

(

MDistance &

val

)

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

Examples:

MStatus setMAngle

(

MAngle &

val

)

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

Examples:

MStatus setMTime

(

MTime &

val

)

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

Examples:

MStatus setChar

(

char

val

)

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

Examples:

MStatus setString

(

const MString &

val

)

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

Examples:

MPlug & operator=

(

const MPlug &

other

)

Assignment operator.

Copies one plug to another.

Networked plugs are not allowed to be duplicated so if the RHS is a networked plug then a non-networked version is returned.

Parameters

[in]

other

the plug to be copied

Returns

A reference to the copied plug

MPlug operator[]

(

unsigned int

physicalIndex

)

const

This method will find and return a plug with the given physical index.

This is the same as the elementByPhysicalIndex method.

Parameters

[in]

physicalIndex

Array index of child plug

Returns

A plug with the given index

bool operator==

(

const MPlug &

other

)

const

Comparison operator for MPlugs.

Plugs are considered equal if they refer to the same node and attribute unless both plugs are networked. In such cases a pointer comparison is done as there can only be one version of a networked plug.

If either or both plugs are null, the plugs are not considered equal.

Parameters

[in]

other

Other plug to compare against

Returns

• true If the plugs are equal
• false If the plugs are not equal

bool operator==

(

const MObject &

attr

)

const

Comparison operator for a plug and an attribute.

This actually compares the plug's attribute against the other attribute.

Parameters

[in]

attr

Attribute to compare against

Returns

• true If the plug's attribute is equal
• false If the plug's attribute is not equal

bool operator!=

(

const MPlug &

other

)

const

The inequality operator for MPlugs.

Plugs are considered equal if they refer to the same node and attribute unless both plugs are networked. In such cases a pointer comparison is done as there can only be one version of a networked plug.

If either or both plugs are null, the plugs are not considered equal.

Parameters

[in]

other

Other plug to compare against

Returns

• true If the plugs are not equal
• false If the plugs are equal

bool operator!=

(

const MObject &

attr

)

const

The inequality operator for a plug and an attribute.

This actually compares the plug's attribute against the other attribute.

Parameters

[in]

attr

Attribute to compare against

Returns

• true If the plug's attribute is not equal
• false If the plug's attribute is equal

MStatus setNumElements

(

unsigned int

elements

)

The method is used to pre-allocate the number of elements that an array plug will contain.

The plug passed to this method must be an array plug and there must be no elements already allocated.

The numElements() method is used to find the number of elements already in the array plug.

Parameters

[in]

elements

new array size

Returns

• kSuccess array plug size was changed
• kFailure failed to change array plug size, plug is not array or array size is already non-zero.

bool isSource

(

MStatus *

ReturnStatus = nullptr

)

const

Determines if this plug is connected as a source.

Parameters

[out]

ReturnStatus

pointer to a status code object

Returns

• true plug is connected as a source
• false plug is not connected as a source

Status Codes:

• MS::kSuccess Method returned successfully
• MS::kFailure Object error

Examples:

bool isDestination

(

MStatus *

ReturnStatus = nullptr

)

const

Determines if this plug is connected as a destination.

Parameters

[out]

ReturnStatus

pointer to a status code object

Returns

• true plug is connected as a destination
• false plug is not connected as a destination

Status Codes:

• MS::kSuccess Method returned successfully
• MS::kFailure Object error

Examples:

const char * className ( )

static

Returns the name of this class.

Returns

Name of this class.

MStatus getValue

(

MObject &

val

)

const

NO SCRIPT SUPPORT.

Retrieve the current value of the attribute this plug references.

This method returns a copy of the attribute value for the plug and not a reference. The setObject method of this class can be used to modify the plug's value.

Python Notes

This method is not available from Python. Use asMObject() instead.

Parameters

[out]

val

Storage for the attribute value

Returns

Status Code

Status Codes:

• MS::kSuccess Value exists and is non-null, and contains the correct information
• MS::kFailure Either the value is a nullptr value (kFailure) or the value does not exist (kObjectDoesNotExist failure)

Examples:

MStatus getValue

(

MDataHandle &

val

)

const

NO SCRIPT SUPPORT.

Retrieve the current value of the attribute this plug references.

This method is useful when wanting to retrieve an entire set of values from an array plug with a single call. An MArrayDataHandle can then be constructed from the returned MDataHandle to access the array data values.

After using the returned MDataHandle, the caller must destroy the handle using MPlug::destructHandle().

Parameters

[out]

val

Storage for the attribute value

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure Object error or internal failure

MStatus getValue

(

double &

val

)

const

NO SCRIPT SUPPORT.

Retrieve the current value of the attribute this plug references.

Python Notes

This method is not available from Python. Use asDouble() instead.

Parameters

[out]

val

Storage for the attribute value

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure

MStatus getValue

(

float &

val

)

const

NO SCRIPT SUPPORT.

Retrieve the current value of the attribute this plug references.

Python Notes

This method is not available from Python. Use asFloat() instead.

Parameters

[out]

val

Storage for the attribute value

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure

MStatus getValue

(

MInt64 &

val

)

const

NO SCRIPT SUPPORT.

Retrieve the current value of the attribute this plug references.

Python Notes

This method is not available from Python. Use asInt64() instead.

Parameters

[out]

val

Storage for the attribute value

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure

MStatus getValue

(

int &

val

)

const

NO SCRIPT SUPPORT.

Retrieve the current value of the attribute this plug references.

Python Notes

This method is not available from Python. Use asInt() instead.

Parameters

[out]

val

Storage for the attribute value

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure

MStatus getValue

(

short &

val

)

const

NO SCRIPT SUPPORT.

Retrieve the current value of the attribute this plug references.

Python Notes

This method is not available from Python. Use asShort() instead.

Parameters

[out]

val

Storage for the attribute value

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure

MStatus getValue

(

bool &

val

)

const

NO SCRIPT SUPPORT.

Retrieve the current value of the attribute this plug references.

Python Notes

This method is not available from Python. Use asBool() instead.

Parameters

[out]

val

Storage for the attribute value

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure

MStatus getValue

(

MDistance &

val

)

const

NO SCRIPT SUPPORT.

Retrieve the current value of the attribute this plug references.

Python Notes

This method is not available from Python. Use asMDistance() instead.

Parameters

[out]

val

Storage for the attribute value

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure

MStatus getValue

(

MAngle &

val

)

const

NO SCRIPT SUPPORT.

Retrieve the current value of the attribute this plug references.

Python Notes

This method is not available from Python. Use asMAngle() instead.

Parameters

[out]

val

Storage for the attribute value

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure

MStatus getValue

(

MTime &

val

)

const

NO SCRIPT SUPPORT.

Retrieve the current value of the attribute this plug references.

Python Notes

This method is not available from Python. Use asMTime() instead.

Parameters

[out]

val

Storage for the attribute value

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure

MStatus getValue

(

char &

val

)

const

NO SCRIPT SUPPORT.

Retrieve the current value of the attribute this plug references.

Python Notes

This method is not available from Python. Use asChar() instead.

Parameters

[out]

val

Storage for the attribute value

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure

MStatus getValue

(

MString &

val

)

const

NO SCRIPT SUPPORT.

Retrieve the current value of the attribute this plug references.

Python Notes

This method is not available from Python. Use asString() instead.

Parameters

[out]

val

Storage for the attribute value

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure Object error or internal failure

MStatus setValue

(

MObject &

val

)

NO SCRIPT SUPPORT.

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Python Notes

This method is not available from Python. Use setMObject() instead.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

Examples:

MStatus setValue

(

MPxData *

val

)

NO SCRIPT SUPPORT.

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Python Notes

This method is not available from Python. Use setMPxData() instead.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

MStatus setValue

(

MDataHandle &

handle

)

NO SCRIPT SUPPORT.

Set the current value of the attribute this plug references with the values in the handle.

This method is most useful when the plug is an array plug, and you've filled the handle with data. Sending the value using this version of setValue will set the handle's data into the datablock and send out the appropriate attributeChanged messages to update the UI related to the attribute.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Python Notes

This method is not available from Python. Use setMDataHandle() instead.

Parameters

[in]

handle

The handle containing the data to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

MStatus setValue

(

double

val

)

NO SCRIPT SUPPORT.

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Python Notes

This method is not available from Python. Use setDouble() instead.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

MStatus setValue

(

float

val

)

NO SCRIPT SUPPORT.

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Python Notes

This method is not available from Python. Use setFloat() instead.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

MStatus setValue

(

MInt64

val

)

NO SCRIPT SUPPORT.

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Python Notes

This method is not available from Python. Use setInt64() instead.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

MStatus setValue

(

int

val

)

NO SCRIPT SUPPORT.

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Python Notes

This method is not available from Python. Use setInt() instead.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

MStatus setValue

(

short

val

)

NO SCRIPT SUPPORT.

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Python Notes

This method is not available from Python. Use setShort() instead.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

MStatus setValue

(

bool

val

)

NO SCRIPT SUPPORT.

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Python Notes

This method is not available from Python. Use setBool() instead.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

MStatus setValue

(

MDistance &

val

)

NO SCRIPT SUPPORT.

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Python Notes

This method is not available from Python. Use setMDistance() instead.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

MStatus setValue

(

MAngle &

val

)

NO SCRIPT SUPPORT.

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Python Notes

This method is not available from Python. Use setMAngle() instead.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

MStatus setValue

(

MTime &

val

)

NO SCRIPT SUPPORT.

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Python Notes

This method is not available from Python. Use setMTime() instead.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

MStatus setValue

(

char

val

)

NO SCRIPT SUPPORT.

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Python Notes

This method is not available from Python. Use setChar() instead.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

MStatus setValue

(

const MString &

val

)

NO SCRIPT SUPPORT.

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Python Notes

This method is not available from Python. Use setString() instead.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

MStatus setValue

(

const char *

val

)

NO SCRIPT SUPPORT.

Set the current value of the attribute this plug references.

If the attribute is the destination of a connection then setting the value will have no effect as once the node is re-evaluated the attribute value will be reset.

Python Notes

This method is not available from Python. Use setString() instead.

Parameters

[in]

val

The value to which the attribute will be set

Returns

Status Code

Status Codes:

• MS::kSuccess
• MS::kFailure
• MS::kLicenseFailure

MPlug operator[]

(

MObject &

attr

)

const

NO SCRIPT SUPPORT.

Returns a plug to the given attribute.

This is only valid for attributes with no arrays in their ancestry.

Parameters

[in]

attr

The attribute of the plug

Returns

A plug referring to the given attribute, or a nullptr plug if the operation fails.

operator MObject

(

)

const

NO SCRIPT SUPPORT.

This method returns the attribute for this plug.

Returns

The attribute for this plug

bool operator!

(

)

const

NO SCRIPT SUPPORT.

Returns true if this plug is not valid.

A plug is considered valid if it refers to an attribute.

Returns

• true The plug is NOT valid
• false The plug is valid

MObject asMObject	(	const MDGContext &	ctx,
		MStatus *	ReturnStatus = nullptr
	)		const

This method is obsolete.

Retrieve the value in the given context of the attribute this plug references.

[From Maya 2018]

Deprecated:

Use asMObject(MStatus*) instead. If needed, use MDGContextGuard to switch the context.

Note

Use this method only when you are deliberately evaluating at a different context, e.g. at a different time, otherwise use the overload with no context.

This method returns a copy of the attribute value for the plug and not a reference. The setObject method of this class can be used to modify the plug's value.

Parameters

[in]	ctx	Context in which to evaluate the plug
[out]	ReturnStatus	Status Code

Returns

Value of plug as an MObject

Status Codes:

• MS::kSuccess Value exists and is non-null, and contains the correct information
• MS::kFailure Either the value is a nullptr value (kFailure) or the value does not exist (kObjectDoesNotExist failure)

MDataHandle asMDataHandle	(	const MDGContext &	ctx,
		MStatus *	ReturnStatus = nullptr
	)		const

This method is obsolete.

Retrieve the value in the given context of the attribute this plug references.

[From Maya 2018]

Deprecated:

Use asMDataHandle(MStatus*) instead. If needed, use MDGContextGuard to switch the context.

Note

Use this method only when you are deliberately evaluating at a different context, e.g. at a different time, otherwise use the overload with no context.

This method is useful when wanting to retrieve an entire set of values from an array plug with a single call. An MArrayDataHandle can then be constructed from the returned MDataHandle to access the array data values.

Parameters

[in]	ctx	Context in which to evaluate the plug
[out]	ReturnStatus	Status Code

Returns

Value of plug as an MDataHandle. When done using the returned handle, the caller must destroy it using MPlug::destructHandle().

Status Codes:

• MS::kSuccess
• MS::kFailure

double asDouble	(	const MDGContext &	ctx,
		MStatus *	ReturnStatus = nullptr
	)		const

This method is obsolete.

Retrieve the value in the given context of the attribute this plug references.

[From Maya 2018]

Deprecated:

Use asDouble(MStatus*) instead. If needed, use MDGContextGuard to switch the context.

Note

Use this method only when you are deliberately evaluating at a different context, e.g. at a different time, otherwise use the overload with no context.

Parameters

[in]	ctx	Context in which to evaluate the plug
[out]	ReturnStatus	Status Code

Returns

Value of plug as a double

Status Codes:

• MS::kSuccess
• MS::kFailure

float asFloat	(	const MDGContext &	ctx,
		MStatus *	ReturnStatus = nullptr
	)		const

This method is obsolete.

Retrieve the value in the given context of the attribute this plug references.

[From Maya 2018]

Deprecated:

Use asFloat(MStatus*) instead. If needed, use MDGContextGuard to switch the context.

Note

Use this method only when you are deliberately evaluating at a different context, e.g. at a different time, otherwise use the overload with no context.

Parameters

[in]	ctx	Context in which to evaluate the plug
[out]	ReturnStatus	Status Code

Returns

Value of plug as a float

Status Codes:

• MS::kSuccess
• MS::kFailure

MInt64 asInt64	(	const MDGContext &	ctx,
		MStatus *	ReturnStatus = nullptr
	)		const

This method is obsolete.

Retrieve the value in the given context of the attribute this plug references.

[From Maya 2018]

Deprecated:

Use asInt64(MStatus*) instead. If needed, use MDGContextGuard to switch the context.

Note

Use this method only when you are deliberately evaluating at a different context, e.g. at a different time, otherwise use the overload with no context.

Parameters

[in]	ctx	Context in which to evaluate the plug
[out]	ReturnStatus	Status Code

Returns

Value of plug as an int

Status Codes:

• MS::kSuccess
• MS::kFailure

int asInt	(	const MDGContext &	ctx,
		MStatus *	ReturnStatus = nullptr
	)		const

This method is obsolete.

Retrieve the value in the given context of the attribute this plug references.

[From Maya 2018]

Deprecated:

Use asInt(MStatus*) instead. If needed, use MDGContextGuard to switch the context.

Note

Use this method only when you are deliberately evaluating at a different context, e.g. at a different time, otherwise use the overload with no context.

Parameters

[in]	ctx	Context in which to evaluate the plug
[out]	ReturnStatus	Status Code

Returns

Value of plug as an int

Status Codes:

• MS::kSuccess
• MS::kFailure

short asShort	(	const MDGContext &	ctx,
		MStatus *	ReturnStatus = nullptr
	)		const

This method is obsolete.

Retrieve the value in the given context of the attribute this plug references.

[From Maya 2018]

Deprecated:

Use asShort(MStatus*) instead. If needed, use MDGContextGuard to switch the context.

Note

Use this method only when you are deliberately evaluating at a different context, e.g. at a different time, otherwise use the overload with no context.

Parameters

[in]	ctx	Context in which to evaluate the plug
[out]	ReturnStatus	Status Code

Returns

Value of plug as a short

Status Codes:

• MS::kSuccess
• MS::kFailure

bool asBool	(	const MDGContext &	ctx,
		MStatus *	ReturnStatus = nullptr
	)		const

This method is obsolete.

Retrieve the value in the given context of the attribute this plug references.

[From Maya 2018]

Deprecated:

Use asBool(MStatus*) instead. If needed, use MDGContextGuard to switch the context.

Note

Use this method only when you are deliberately evaluating at a different context, e.g. at a different time, otherwise use the overload with no context.

Parameters

[in]	ctx	Context in which to evaluate the plug
[out]	ReturnStatus	Status Code

Returns

Value of plug as a bool

Status Codes:

• MS::kSuccess
• MS::kFailure

MDistance asMDistance	(	const MDGContext &	ctx,
		MStatus *	ReturnStatus = nullptr
	)		const

This method is obsolete.

Retrieve the value in the given context of the attribute this plug references.

[From Maya 2018]

Deprecated:

Use asMDistance(MStatus*) instead. If needed, use MDGContextGuard to switch the context.

Note

Use this method only when you are deliberately evaluating at a different context, e.g. at a different time, otherwise use the overload with no context.

Parameters

[in]	ctx	Context in which to evaluate the plug
[out]	ReturnStatus	Status Code

Returns

Value of plug as an MDistance

Status Codes:

• MS::kSuccess
• MS::kFailure

MAngle asMAngle	(	const MDGContext &	ctx,
		MStatus *	ReturnStatus = nullptr
	)		const

This method is obsolete.

Retrieve the value in the given context of the attribute this plug references.

[From Maya 2018]

Deprecated:

Use asMAngle(MStatus*) instead. If needed, use MDGContextGuard to switch the context.

Note

Use this method only when you are deliberately evaluating at a different context, e.g. at a different time, otherwise use the overload with no context.

Parameters

[in]	ctx	Context in which to evaluate the plug
[out]	ReturnStatus	Status Code

Returns

Value of plug as an MAngle

Status Codes:

• MS::kSuccess
• MS::kFailure

MTime asMTime	(	const MDGContext &	ctx,
		MStatus *	ReturnStatus = nullptr
	)		const

This method is obsolete.

Retrieve the value in the given context of the attribute this plug references.

[From Maya 2018]

Deprecated:

Use asMTime(MStatus*) instead. If needed, use MDGContextGuard to switch the context.

Note

Use this method only when you are deliberately evaluating at a different context, e.g. at a different time, otherwise use the overload with no context.

Parameters

[in]	ctx	Context in which to evaluate the plug
[out]	ReturnStatus	Status Code

Returns

Value of plug as an MTime

Status Codes:

• MS::kSuccess
• MS::kFailure

char asChar	(	const MDGContext &	ctx,
		MStatus *	ReturnStatus = nullptr
	)		const

This method is obsolete.

Retrieve the value in the given context of the attribute this plug references.

[From Maya 2018]

Deprecated:

Use asChar(MStatus*) instead. If needed, use MDGContextGuard to switch the context.

Note

Use this method only when you are deliberately evaluating at a different context, e.g. at a different time, otherwise use the overload with no context.

Parameters

[in]	ctx	Context in which to evaluate the plug
[in]	ReturnStatus	Status Code

Returns

Value of plug as a char

Status Codes:

• MS::kSuccess
• MS::kFailure

MString asString	(	const MDGContext &	ctx,
		MStatus *	ReturnStatus = nullptr
	)		const

This method is obsolete.

Retrieve the value in the given context of the attribute this plug references.

[From Maya 2018]

Deprecated:

Use asString(MStatus*) instead. If needed, use MDGContextGuard to switch the context.

Note

Use this method only when you are deliberately evaluating at a different context, e.g. at a different time, otherwise use the overload with no context.

Parameters

[in]	ctx	Context in which to evaluate the plug
[out]	ReturnStatus	Status Code

Returns

Value of plug as an MString

Status Codes:

• MS::kSuccess
• MS::kFailure Object error or internal failure

MStatus getValue	(	MObject &	val,
		MDGContext &	ctx
	)		const

This method is obsolete.

[From Maya 2018]

Deprecated:

Use getValue(MObject&) to get the value in the current evaluation context. If needed, use MDGContextGuard to switch the context.

Parameters

[out]	val
[in]	ctx

MStatus getValue	(	MDataHandle &	val,
		MDGContext &	ctx
	)		const

This method is obsolete.

[From Maya 2018]

Deprecated:

Use getValue(MDataHandle&) to get the value in the current evaluation context. If needed, use MDGContextGuard to switch the context.

Parameters

[out]	val
[in]	ctx

MStatus getValue	(	double &	val,
		MDGContext &	ctx
	)		const

This method is obsolete.

[From Maya 2018]

Deprecated:

Use getValue(double&) to get the value in the current evaluation context. If needed, use MDGContextGuard to switch the context.

Parameters

[out]	val
[in]	ctx

MStatus getValue	(	float &	val,
		MDGContext &	ctx
	)		const

This method is obsolete.

[From Maya 2018]

Deprecated:

Use getValue(float&) to get the value in the current evaluation context. If needed, use MDGContextGuard to switch the context.

Parameters

[out]	val
[in]	ctx

MStatus getValue	(	MInt64 &	val,
		MDGContext &	ctx
	)		const

This method is obsolete.

[From Maya 2018]

Deprecated:

Use getValue(MInt64&) to get the value in the current evaluation context. If needed, use MDGContextGuard to switch the context.

Parameters

[out]	val
[in]	ctx

MStatus getValue	(	int &	val,
		MDGContext &	ctx
	)		const

This method is obsolete.

[From Maya 2018]

Deprecated:

Use getValue(int&) to get the value in the current evaluation context. If needed, use MDGContextGuard to switch the context.

Parameters

[out]	val
[in]	ctx

MStatus getValue	(	short &	val,
		MDGContext &	ctx
	)		const

This method is obsolete.

[From Maya 2018]

Deprecated:

Use getValue(short&) to get the value in the current evaluation context. If needed, use MDGContextGuard to switch the context.

Parameters

[out]	val
[in]	ctx

MStatus getValue	(	bool &	val,
		MDGContext &	ctx
	)		const

This method is obsolete.

[From Maya 2018]

Deprecated:

Use getValue(bool&) to get the value in the current evaluation context. If needed, use MDGContextGuard to switch the context.

Parameters

[out]	val
[in]	ctx

MStatus getValue	(	MDistance &	val,
		MDGContext &	ctx
	)		const

This method is obsolete.

[From Maya 2018]

Deprecated:

Use getValue(MDistance&) to get the value in the current evaluation context. If needed, use MDGContextGuard to switch the context.

Parameters

[out]	val
[in]	ctx

MStatus getValue	(	MAngle &	val,
		MDGContext &	ctx
	)		const

This method is obsolete.

[From Maya 2018]

Deprecated:

Use getValue(MAngle&) to get the value in the current evaluation context. If needed, use MDGContextGuard to switch the context.

Parameters

[out]	val
[in]	ctx

MStatus getValue	(	MTime &	val,
		MDGContext &	ctx
	)		const

This method is obsolete.

[From Maya 2018]

Deprecated:

Use getValue(MTime&) to get the value in the current evaluation context. If needed, use MDGContextGuard to switch the context.

Parameters

[out]	val
[in]	ctx

MStatus getValue	(	char &	val,
		MDGContext &	ctx
	)		const

This method is obsolete.

[From Maya 2018]

Deprecated:

Use getValue(char&) to get the value in the current evaluation context. If needed, use MDGContextGuard to switch the context.

Parameters

[out]	val
[in]	ctx

MStatus getValue	(	MString &	val,
		MDGContext &	ctx
	)		const

This method is obsolete.

[From Maya 2018]

Deprecated:

Use getValue(MString&) to get the value in the current evaluation context. If needed, use MDGContextGuard to switch the context.

Parameters

[out]	val
[in]	ctx

---

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

• MPlug.h
• MPlug.cpp