C++ API Reference

Base class for user defined dependency nodes. More...

#include <MPxNode.h>

+ Inheritance diagram for MPxNode:

Public Types

enum  Type {
  kDependNode, kLocatorNode, kDeformerNode, kManipContainer,
  kSurfaceShape, kFieldNode, kEmitterNode, kSpringNode,
  kIkSolverNode, kHardwareShader, kHwShaderNode, kTransformNode,
  kObjectSet, kFluidEmitterNode, kImagePlaneNode, kParticleAttributeMapperNode,
  kCameraSetNode, kConstraintNode, kManipulatorNode, kMotionPathNode,
  kClientDeviceNode, kThreadedDeviceNode, kAssembly, kSkinCluster,
  kGeometryFilter, kBlendShape, kLast
}
 Defines the type of node. More...
 
enum  SchedulingType {
  kParallel, kSerial, kGloballySerial, kUntrusted ,
  kDefaultScheduling = kSerial, kSerialize = kSerial, kGloballySerialize = kGloballySerial
}
 Defines the degree of parallelism of a node. More...
 

Public Member Functions

 MPxNode ()
 Constructor. More...
 
virtual ~MPxNode ()
 Destructor.
 
virtual void postConstructor ()
 Post constructor. More...
 
virtual MStatus compute (const MPlug &, MDataBlock &)
 This method should be overridden in user defined nodes. More...
 
virtual bool getInternalValue (const MPlug &, MDataHandle &)
 This method is overridden by nodes that store attribute data in some internal format. More...
 
virtual bool setInternalValue (const MPlug &, const MDataHandle &)
 This method is overridden by nodes that store attribute data in some internal format. More...
 
virtual int internalArrayCount (const MPlug &) const
 This method is overridden by nodes that have internal array attributes which are not stored in Maya's datablock. More...
 
virtual void copyInternalData (MPxNode *)
 This method is overridden by nodes that store attribute data in some internal format. More...
 
virtual MStatus legalConnection (const MPlug &, const MPlug &, bool asSrc, bool &isLegal) const
 This method allows you to check for legal connections being made to attributes of this node. More...
 
virtual MStatus legalDisconnection (const MPlug &, const MPlug &, bool asSrc, bool &isLegal) const
 This method allows you to check for legal disconnections being made to attributes of this node. More...
 
virtual MStatus setDependentsDirty (const MPlug &plug, MPlugArray &plugArray)
 This method can be overridden in user defined nodes to specify which plugs should be set dirty based upon an input plug {plugBeingDirtied} which Maya is marking dirty. More...
 
virtual MStatus preEvaluation (const MDGContext &context, const MEvaluationNode &evaluationNode)
 Prepare a node's internal state for threaded evaluation. More...
 
virtual MStatus postEvaluation (const MDGContext &context, const MEvaluationNode &evaluationNode, PostEvaluationType evalType)
 Clean up node's internal state after threaded evaluation. More...
 
virtual SchedulingType schedulingType () const
 When overridden this method controls the degree of parallelism supported by the node during threaded evaluation. More...
 
virtual void getCacheSetup (const MEvaluationNode &, MNodeCacheDisablingInfo &, MNodeCacheSetupInfo &, MObjectArray &) const
 Provide node-specific setup info for the Cached Playback system. More...
 
virtual void configCache (const MEvaluationNode &, MCacheSchema &) const
 Defines the node's behavior when participating in Cached Playback. More...
 
virtual MTimeRange transformInvalidationRange (const MPlug &source, const MTimeRange &input) const
 Override this method to register this node as an Invalidation-Range-Transformation kernel (IRT kernel) An IRT kernel node will change the invalidation time range for its downstream nodes For example, Dynamics-solver will transform invalidation time range [a,b] to [a,+inf) And Clip-Time-Editor will send out the invalidation range for each of the clip [a,b] to ( [t0+a,t0+b] U [t1+a,t1+b] U [t2+a,t2+b] U ... More...
 
bool hasInvalidationRangeTransformation () const
 Checks if this MPxNode derived node overrides the MPxNode::transformInvalidationRange method.
 
virtual MStatus connectionMade (const MPlug &, const MPlug &, bool asSrc)
 This method gets called when connections are made to attributes of this node. More...
 
virtual MStatus connectionBroken (const MPlug &, const MPlug &, bool asSrc)
 This method gets called when connections are broken with attributes of this node. More...
 
virtual MStatus dependsOn (const MPlug &, const MPlug &, bool &depends) const
 This method may be overridden by the user defined node. More...
 
virtual bool isPassiveOutput (const MPlug &) const
 This method may be overridden by the user defined node if it wants to provide output attributes which do not prevent value modifications to the destination attribute. More...
 
virtual MStatus shouldSave (const MPlug &, bool &isSaving)
 This method may be overridden by the user defined node. More...
 
virtual MPlug passThroughToOne (const MPlug &) const
 This method may be overridden by nodes that have a one-to-one relationship between an input attribute and a corresponding output attribute. More...
 
virtual bool passThroughToMany (const MPlug &, MPlugArray &) const
 This method is overridden by nodes that want to control the traversal behavior of some Maya search algorithms which traverse the history/future of shape nodes looking for directly related nodes. More...
 
virtual Type type () const
 Returns the type of node that this is. More...
 
virtual bool isAbstractClass () const
 Override this class to return true if this node is an abstract node. More...
 
virtual bool isTrackingTopology () const
 Override this class to return true if this node wants to track topology. More...
 
virtual MStringArray getFilesToArchive (bool shortName=false, bool unresolvedName=false, bool markCouldBeImageSequence=false) const
 Use this method to return all external files used by this node. More...
 
virtual void getExternalContent (MExternalContentInfoTable &table) const
 Returns the external content (files) that this node depends on. More...
 
bool addExternalContentForFileAttr (MExternalContentInfoTable &, const MObject &attr) const
 Adds content info to the specified table from a file path attribute. More...
 
bool setExternalContentForFileAttr (const MObject &attr, const MExternalContentLocationTable &)
 Sets content info in the specified attribute from the table. More...
 
virtual void setExternalContent (const MExternalContentLocationTable &)
 Changes the location of external content in batch. More...
 
virtual MTypeId typeId () const
 Returns the TYPEID of this node. More...
 
virtual MString typeName () const
 Returns the type name of this node. More...
 
virtual MString name () const
 Returns the name of this particular instance of this class. More...
 
virtual MObject thisMObject () const
 Returns the MObject associated with this user defined node. More...
 
virtual MStatus setExistWithoutInConnections (bool flag)
 This method specifies whether or not the node can exist without input connections. More...
 
virtual bool existWithoutInConnections (MStatus *ReturnStatus=NULL) const
 Determines whether or not this node can exist without input connections. More...
 
virtual MStatus setExistWithoutOutConnections (bool flag)
 This method specifies whether or not the node can exist without output connections. More...
 
virtual bool existWithoutOutConnections (MStatus *ReturnStatus=NULL) const
 Determines whether or not this node can exist without output connections. More...
 
void _setMPSafe (bool isMPSafe)
 This method is obsolete. More...
 
MDataBlock _forceCache (const MDGContext &)
 This method is obsolete. More...
 
virtual bool getInternalValueInContext (const MPlug &, MDataHandle &, MDGContext &)
 This method is obsolete. More...
 
virtual bool setInternalValueInContext (const MPlug &, const MDataHandle &, MDGContext &)
 This method is obsolete. More...
 
virtual int internalArrayCount (const MPlug &, const MDGContext &) const
 This method is obsolete. More...
 

Static Public Member Functions

static MStatus addAttribute (const MObject &attr)
 This method adds a new attribute to a user defined node type during the type's initialization. More...
 
static MStatus inheritAttributesFrom (const MString &parentClassName)
 This method allows a class of plugin node to inherit all of the attributes of a second class of plugin node. More...
 
static MStatus attributeAffects (const MObject &whenChanges, const MObject &isAffected)
 This method specifies that a particular input attribute affects a specific output attribute. More...
 
static MStatus attributeAffects (const MObject &whenChanges, const MObject &isAffected, bool affectsTopology)
 This method is an extension to the other version of the attributeAffects method. More...
 
static const char * className ()
 Returns the name of this class. More...
 

Static Public Attributes

static MObject message
 message attribute
 
static MObject isHistoricallyInteresting
 is historically interesting attribute
 
static MObject caching
 caching attribute
 
static MObject state
 state attribute
 
static MObject frozen
 frozen attribute
 

Protected Member Functions

virtual MDataBlock forceCache ()
 USE _forceCache() IN SCRIPT. More...
 
virtual MStatus setDoNotWrite (bool flag)
 USE _setDoNotWrite() IN SCRIPT. More...
 
virtual bool doNotWrite (MStatus *ReturnStatus=NULL) const
 USE _doNotWrite() IN SCRIPT. More...
 
virtual void setMPSafe (bool isMPSafe)
 This method is obsolete. More...
 
virtual MDataBlock forceCache (const MDGContext &)
 This method is obsolete. More...
 

Detailed Description

Base class for user defined dependency nodes.

MPxNode is the the parent class for user defined dependency nodes. A dependency node is an object that resides in the dependency graph. It computes output attributes based on a set of input attributes. When an input changes, the compute method is called for each dependent output.

The dependency graph is made up of nodes that have connections between their attributes. When an attribute changes, recomputation propagates through the graph until all affected values have been updated.

When writing a dependency node, there is a very basic rule that should be observed. The outputs should be calculated only using the values of the inputs. All information about the world outside the node should come from input attributes. If this rule is not observed, then the results may be unpredictable.

Developers must decide whether to support the HasNoEffect setting of the state attribute. {HasNoEffect} means that a node should pass through all data without performing computations on it. For example, a deformer node will pass geometry through unmodified when state is set to HasNoEffect. It is up the the plug-in writer to observe the HasNoEffect mode if it is relevant to the type of node.

Examples:
AbcImport/AlembicNode.h, affectsNode/affectsNode.cpp, animCubeNode/animCubeNode.cpp, anisotropicShader/anisotropicShader.cpp, apiMeshShape/apiMeshCreator.h, arcLenNode/arcLenNode.cpp, backfillShader/backfillShader.cpp, blindDataShader/blindDataMesh.h, brickShader/brickShader.cpp, buildRotationNode/buildRotationNode.cpp, cellShader/cellShader.cpp, cgFx/cgfxShaderNode.cpp, cgFx/cgfxShaderNode.h, cgFx/cgfxVector.h, checkerShader/checkerShader.cpp, circleNode/circleNode.cpp, clearcoat.cpp, closestPointOnCurve/closestPointOnCurveNode.h, compositingShader/compositingShader.cpp, contrastShader/contrastShader.cpp, customComponentTagNode/customComponentTagNode.cpp, depthShader/depthShader.cpp, displacementShader/displacementShader.cpp, dx11Shader/dx11ConeAngleToHotspotConverter.h, dx11Shader/dx11Shader.cpp, dx11Shader/dx11Shader.h, exampleFalloff/smoothFalloffNode.cpp, exampleFalloff/smoothFalloffNode.h, exampleRampAttribute/exampleMRampAttribute.cpp, fileTexture/fileTexture.cpp, flameShader/flameShader.cpp, footPrintNode_AnimatedMaterial/footPrintNode_GeometryOverride_AnimatedMaterial.cpp, footPrintNode_GeometryOverride/footPrintNode_GeometryOverride.cpp, fullLoftNode/fullLoftNode.cpp, gammaShader/gammaShader.cpp, genericAttributeNode/genericAttributeNode.cpp, geometrytools.cpp, geomShader/geomShader.cpp, gpuCache/gpuCacheCmd.cpp, gpuCache/gpuCacheShapeNode.cpp, gpuCache/gpuCacheShapeNode.h, hlslShader/hlslShader.cpp, hlslShader/hlslShader.h, interpShader/interpShader.cpp, jitterNode/jitterNode.cpp, lambertShader/lambertShader.cpp, latticeNoise/latticeNoise.h, lavaShader/lavaShader.cpp, lightShader/lightShader.cpp, meshOpCmd/polyModifierNode.h, MetadataSample/tweakMetadataNode.h, mixtureShader/mixtureShader.cpp, multiCurveNode/multiCurveNode.cpp, noiseShader/noiseShader.cpp, onbShader/onbShader.cpp, phongShader/phongShader.cpp, pointOnMeshInfo/pointOnMeshInfoNode.h, pointOnSubdNode/pointOnSubdNode.h, renderAccessNode/renderAccessNode.cpp, sceneAssembly/adskPrepareRenderGlobals.h, sceneAssembly/assemblyReference.cpp, sceneAssembly/assemblyReference.h, shadowMatteShader/shadowMatteShader.cpp, shellNode/shellNode.cpp, shiftNode/shiftNode.cpp, simpleEvaluationNode/simpleEvaluationNode.cpp, simpleLoftNode/simpleLoftNode.cpp, simpleNoiseShader/simpleNoiseShader.cpp, simplePhysicsEngine/simplePhysicsEngine.cpp, simpleSimulationNode/simpleSimulationNode.cpp, simpleSkipNode/simpleSkipNode.cpp, sineNode/sineNode.cpp, slopeShader/slopeShaderNode.h, solidCheckerShader/solidCheckerShader.cpp, splitUVCmd/polyModifierNode.h, stringFormatNode/stringFormatNode.cpp, testMTopologyEvaluator/testMTopologyEvaluator.h, testNobjectNode/testNobjectNode.h, testNpassiveNode/testNpassiveNode.h, testNsolverNode/testNsolverNode.h, testNucleusNode/testNucleusNode.h, topologyTrackingNode/topologyTrackingNode.cpp, transCircleNode/transCircleNode.cpp, volumeShader/volumeShader.cpp, and weightListNode/weightListNode.cpp.

Member Enumeration Documentation

enum Type

Defines the type of node.

Enumerator
kDependNode 

Custom node derived from MPxNode.

kLocatorNode 

Custom locator derived from MPxLocatorNode.

kDeformerNode 

Custom deformer derived from MPxDeformerNode.

kManipContainer 

Custom container derived from MPxManipContainer.

kSurfaceShape 

Custom shape derived from MPxSurfaceShape.

kFieldNode 

Custom field derived from MPxFieldNode.

kEmitterNode 

Custom emitter derived from MPxEmitterNode.

kSpringNode 

Custom spring derived from MPxSpringNode.

kIkSolverNode 

Custom IK solver derived from MPxIkSolverNode.

kHardwareShader 

Custom shader derived from MPxHardwareShader.

kHwShaderNode 

Custom shader derived from MPxHwShaderNode.

kTransformNode 

Custom transform derived from MPxTransform.

kObjectSet 

Custom set derived from MPxObjectSet.

kFluidEmitterNode 

Custom fluid emitter derived from MpxFluidEmitterNode.

kImagePlaneNode 

Custom image plane derived from MPxImagePlane.

kParticleAttributeMapperNode 

Custom particle attribute mapper derived from MPxParticleAttributeMapperNode.

kCameraSetNode 

Custom director derived from MPxCameraSet.

kConstraintNode 

Custom constraint derived from MPxConstraint.

kManipulatorNode 

Custom manipulator derived from MPxManipulatorNode.

kMotionPathNode 

Custom motionPath derived from MPxMotionPathNode.

kClientDeviceNode 

Custom threaded device derived from MPxThreadedDeviceNode.

kThreadedDeviceNode 

Custom threaded device node.

kAssembly 

Custom assembly derived from MPxAssembly.

kSkinCluster 

Custom deformer derived from MPxSkinCluster.

kGeometryFilter 

Custom deformer derived from MPxGeometryFilter.

kBlendShape 

Custom deformer derived from MPxBlendShape.

kLast 

Last value, used for counting.

Defines the degree of parallelism of a node.

Enumerator
kParallel 

This schedulingType indicates that the node can be evaluated concurrently to any other nodes without restrictions.

kSerial 

Groups are formed for nodes having this ShedulingType when they are directly connected to each other.

Within a same group nodes are guaranteed to not to be concurrently evaluated. However nodes in distinct groups can still be concurently be evaluated.

kGloballySerial 

Nodes having the kGloballySerial SchedulingType are guaranteed not to be evaluated concurrently to any other node having the same schedulingType.

kUntrusted 

Untrusted nodes are guaranteed not to be evaluately concurrently to any other node.

Last value, used for counting

kDefaultScheduling 

This method is obsolete.

as of Maya2017, use kSerial

kSerialize 

This method is obsolete.

as of Maya2017, use kSerial

kGloballySerialize 

This method is obsolete.

as of Maya2017, use kGloballySerial

Constructor & Destructor Documentation

MPxNode ( )

Constructor.

The constructor should never call any methods from MPxNode or make any calls that require the existence of the MObject associated with the user defined node. The postConstructor method should be used to do any initialization of this kind.

Member Function Documentation

MStatus compute ( const MPlug plug,
MDataBlock block 
)
virtual

This method should be overridden in user defined nodes.

Recompute the given output based on the nodes inputs. The plug represents the data value that needs to be recomputed, and the data block holds the storage for all of the node's attributes.

The MDataBlock will provide smart handles for reading and writing this node's attribute values. Only these values should be used when performing computations.

When evaluating the dependency graph, Maya will first call the compute method for this node. If the plug that is provided to the compute indicates that the attribute was defined by the Maya parent node, the compute method should return MS::kUnknownParameter. When this occurs, Maya will call the internal Maya node from which the user-defined node is derived to compute the plug's value.

This means that a user defined node does not need to be concerned with computing inherited output attributes. However, if desired, these can be safely recomputed by this method to change the behaviour of the node.

Parameters
[in]plugplug representing the attribute that needs to be recomputed
[in]blockdata block containing storage for the node's attributes
Returns
Status code
Status Codes:
  • MS::kSuccess Compute was successful
  • MS::kFailure Compute failed

Reimplemented in MPxTransform, MPxPolyTrg, MPxEmitterNode, MPxFieldNode, MPxFluidEmitterNode, and MPxParticleAttributeMapperNode.

Examples:
AbcImport/AlembicNode.h, affectsNode/affectsNode.cpp, animCubeNode/animCubeNode.cpp, anisotropicShader/anisotropicShader.cpp, apiDirectionalLightShape/apiDirectionalLightShape.h, apiMeshShape/apiMeshCreator.h, apiMeshShape/apiMeshShape.h, arcLenNode/arcLenNode.cpp, backfillShader/backfillShader.cpp, blindDataShader/blindDataMesh.h, blindDataShader/blindDataShader.h, brickShader/brickShader.cpp, buildRotationNode/buildRotationNode.cpp, cellShader/cellShader.cpp, cgFx/cgfxShaderNode.h, cgFx/cgfxVector.h, checkerShader/checkerShader.cpp, circleNode/circleNode.cpp, clearcoat.cpp, closestPointOnCurve/closestPointOnCurveNode.h, compositingShader/compositingShader.cpp, contrastShader/contrastShader.cpp, customComponentTagNode/customComponentTagNode.cpp, cvColorNode/cvColorNode.cpp, depthShader/depthShader.cpp, displacementShader/displacementShader.cpp, dx11Shader/dx11ConeAngleToHotspotConverter.h, exampleFalloff/smoothFalloffNode.h, exampleRampAttribute/exampleMRampAttribute.cpp, fileTexture/fileTexture.cpp, flameShader/flameShader.cpp, footPrintManip/footPrintManip.cpp, footPrintNode/footPrintNode.cpp, footPrintNode_AnimatedMaterial/footPrintNode_GeometryOverride_AnimatedMaterial.cpp, footPrintNode_GeometryOverride/footPrintNode_GeometryOverride.cpp, footPrintNode_SubSceneOverride/footPrintNode_SubSceneOverride.cpp, fullLoftNode/fullLoftNode.cpp, gameInputDevice/gameInputDevice.cpp, gammaShader/gammaShader.cpp, genericAttributeNode/genericAttributeNode.cpp, geometrySurfaceConstraint/geometrySurfaceConstraint.h, geometrytools.cpp, geomShader/geomShader.cpp, hwPhongShader/hwPhongShader.h, interpShader/interpShader.cpp, jitterNode/jitterNode.cpp, lambertShader/lambertShader.cpp, latticeNoise/latticeNoise.h, lavaShader/lavaShader.cpp, lightShader/lightShader.cpp, MetadataSample/tweakMetadataNode.h, mixtureShader/mixtureShader.cpp, motionPathNode/motionPathNode.cpp, multiCurveNode/multiCurveNode.cpp, noiseShader/noiseShader.cpp, onbShader/onbShader.cpp, phongShader/phongShader.cpp, pointOnMeshInfo/pointOnMeshInfoNode.h, pointOnSubdNode/pointOnSubdNode.h, randomizerDevice/randomizerDevice.cpp, renderAccessNode/renderAccessNode.cpp, shadowMatteShader/shadowMatteShader.cpp, shellNode/shellNode.cpp, shiftNode/shiftNode.cpp, simpleEvaluationNode/simpleEvaluationNode.cpp, simpleLoftNode/simpleLoftNode.cpp, simpleNoiseShader/simpleNoiseShader.cpp, simplePhysicsEngine/simplePhysicsEngine.cpp, simpleSimulationNode/simpleSimulationNode.cpp, simpleSkipNode/simpleSkipNode.cpp, simpleSpring/simpleSpring.h, sineNode/sineNode.cpp, slopeShader/slopeShaderNode.h, solidCheckerShader/solidCheckerShader.cpp, splatDeformer/splatDeformer.cpp, squaresNode_noDepthTest/squaresNode_noDepthTest.cpp, sseDeformer/sseDeformer.cpp, stringFormatNode/stringFormatNode.cpp, swissArmyManip/swissArmyManip.cpp, testMTopologyEvaluator/testMTopologyEvaluator.h, testNobjectNode/testNobjectNode.h, testNpassiveNode/testNpassiveNode.h, testNsolverNode/testNsolverNode.h, testNucleusNode/testNucleusNode.h, topologyTrackingNode/topologyTrackingNode.cpp, transCircleNode/transCircleNode.cpp, udpDevice/udpDevice.cpp, volumeShader/volumeShader.cpp, vp2BlinnShader/vp2BlinnShader.h, and weightListNode/weightListNode.cpp.
bool getInternalValue ( const MPlug plug,
MDataHandle dataHandle 
)
virtual

This method is overridden by nodes that store attribute data in some internal format.

The internal state of attributes can be set or queried using the setInternal and internal methods of MFnAttribute.

When internal attribute values are queried via getAttr or MPlug::getValue this method is called.

Warning
Do not call getInternalValueInContext(const MPlug& , MDataHandle& , MDGContext& ) inside your override.
Note
All internal data should respect the current context, which may be obtained from MDGContext::current().
Parameters
[in]plugthe attribute that is being queried
[out]dataHandlethe dataHandle to store the attribute value
Returns
  • true the attribute was placed in the datablock
  • false could not handle the specified attribute, pass this request to the default handler
Examples:
apiMeshShape/apiMeshShape.cpp, apiMeshShape/apiMeshShape.h, cgFx/cgfxShaderNode.cpp, cgFx/cgfxShaderNode.h, customImagePlane/customImagePlane.cpp, dx11Shader/dx11Shader.cpp, dx11Shader/dx11Shader.h, glslShader/GLSLShader.cpp, glslShader/GLSLShader.h, gpuCache/gpuCacheShapeNode.cpp, hlslShader/hlslShader.cpp, hlslShader/hlslShader.h, hwPhongShader/hwPhongShader.h, and testMTopologyEvaluator/testMTopologyEvaluator.h.
bool setInternalValue ( const MPlug plug,
const MDataHandle dataHandle 
)
virtual

This method is overridden by nodes that store attribute data in some internal format.

The internal state of attributes can be set or queried using the setInternal and internal methods of MFnAttribute.

When internal attribute values are set via setAttr or MPlug::setValue this method is called.

Another use for this method is to impose attribute limits.

Warning
Do not call setInternalValueInContext(const MPlug& , const MDataHandle& , MDGContext& ) inside your override.
Note
All internal data should respect the current context, which may be obtained from MDGContext::current().
Parameters
[in]plugthe attribute that is being set
[in]dataHandlethe dataHandle containing the value to set
Examples:
apiMeshShape/apiMeshShape.cpp, apiMeshShape/apiMeshShape.h, cgFx/cgfxShaderNode.cpp, cgFx/cgfxShaderNode.h, customImagePlane/customImagePlane.cpp, dx11Shader/dx11Shader.cpp, dx11Shader/dx11Shader.h, glslShader/GLSLShader.cpp, glslShader/GLSLShader.h, gpuCache/gpuCacheShapeNode.cpp, hlslShader/hlslShader.cpp, hlslShader/hlslShader.h, hwPhongShader/hwPhongShader.h, MayaPluginForSpreticle/spReticleLoc.h, and testMTopologyEvaluator/testMTopologyEvaluator.h.
int internalArrayCount ( const MPlug plug) const
virtual

This method is overridden by nodes that have internal array attributes which are not stored in Maya's datablock.

This method is used by Maya to determine the non-sparse count of array elements during file io. If the internal array is stored sparsely, you should return the maximum index of the array plus one. If the internal array is non-sparse then return the length of the array.

This method does not need to be implemented for attributes that are stored in the datablock since Maya will use the datablock size.

If this method is overridden, it should return -1 for attributes which it does not handle. Maya will use the datablock size to determine the array length when -1 is returned.

Note
All internal data should respect the current context, which may be obtained from MDGContext::current().
Parameters
[in]plugthe array plug
void copyInternalData ( MPxNode node)
virtual

This method is overridden by nodes that store attribute data in some internal format.

On duplication this method is called on the duplicated node with the node being duplicated passed as the parameter. Overriding this method gives your node a chance to duplicate any internal data you've been storing and manipulating outside of normal attribute data.

Parameters
[in]nodethe node that is being duplicated

Reimplemented in MPxTransform.

Examples:
cgFx/cgfxShaderNode.h, dx11Shader/dx11Shader.cpp, dx11Shader/dx11Shader.h, and hlslShader/hlslShader.h.
MStatus legalConnection ( const MPlug plug,
const MPlug otherPlug,
bool  asSrc,
bool &  isLegal 
) const
virtual

This method allows you to check for legal connections being made to attributes of this node.

You should return kUnknownParameter to specify that maya should handle this connection if you are unable to determine if it is legal.

Parameters
[in]plugattribute on this node
[in]otherPlugattribute on other node
[in]asSrcis this plug a source of the connection
[in]isLegalset this to true if the connection is legal, false otherwise
Returns
Status code
Status Codes:
  • MS::kSuccess Operation successful
  • MS::kUnknownParameter Unknown attribute
MStatus legalDisconnection ( const MPlug plug,
const MPlug otherPlug,
bool  asSrc,
bool &  isLegal 
) const
virtual

This method allows you to check for legal disconnections being made to attributes of this node.

You should return kUnknownParameter to specify that maya should handle this disconnection if you are unable to determine if it is legal.

Parameters
[in]plugattribute on this node
[in]otherPlugattribute on other node
[in]asSrcis this plug a source of the connection
[out]isLegalset this to true if the disconnection is legal, false otherwise
Returns
Status code
Status Codes:
  • MS::kSuccess Operation successful
  • MS::kUnknownParameter Unknown attribute
MStatus setDependentsDirty ( const MPlug plugBeingDirtied,
MPlugArray affectedPlugs 
)
virtual

This method can be overridden in user defined nodes to specify which plugs should be set dirty based upon an input plug {plugBeingDirtied} which Maya is marking dirty.

The list of plugs for Maya to mark dirty is returned by the plug array {affectedPlugs}. This method handles both dynamic as well as non-dynamic plugs and is useful in the following ways:

  • Allows attributeAffects-style relationships to be handled for dynamically-added attributes. Since MPxNode::attributeAffects can only be used with non-dynamic attributes, use of this method allows a way for all attributes of a node to affect one another, both dynamic and non-dynamic.
  • Provides more flexible relationships than what is available with MPxNode::attributeAffects. For example, you may wish to not dirty plugs when the current frame is one. However, as the routine is called during dirty propagation, there are restrictions on what can be done within the routine, most importantly you must not cause any dependency graph computation. For details, see the IMPORTANT NOTE below.

This method is designed to work harmoniously with MPxNode::attributeAffects on the same node. Alternately, you can do all affects relationships within a yourNode::setDependentsDirty() implementation.

The body of a user-implemented setDependentsDirty() implementation might look like the following example, which causes the plug called "B" to be set dirty whenever plug "A" is changed, i.e. A affects B.

const MString exampleNode::A( "A" ); // Dynamic attribute "A"
MObject exampleNode::attrB; // Non-dynamic attribute "B"
MStatus exampleNode::setDependentsDirty(
const MPlug &plugBeingDirtied,
MPlugArray &affectedPlugs )
{
// This example shows a dynamic attribute (A) affecting a
// non-dynamic attribute (B). For an example of a dynamic
// affecting a dynamic, please the the developer's toolkit
// example plug-in, affectsNode.cpp.
//
if ( plugBeingDirtied.partialName() == A ) {
// "A" is being dirtied. We want "A" to affect "B", so we
// add "B" to the list of plugs for Maya to dirty. Once again,
// please see the IMPORTANT NOTE about what you can and
// cannot do within a setDependentsDirty() routine.
//
MObject thisNode = thisMObject();
MPlug pB( thisNode, exampleNode::attrB );
affectedPlugs.append( pB );
}
return( MS::kSuccess );
}

In the above example, whenever plugBeingDirtied is A, we add B to affectedPlugs so that Maya will dirty B and also any plugs which depend upon B.

For cases where multi compound attributes are dirtied, it is the programmer's responsibility to define ALL affects relationships. Dirtying the parent plug of a multi does not imply that all of its children will be marked dirty. Likewise, dirtying a child attribute does not imply the parent of the multi is dirty. This must be explicitly defined using the affected plug array. The following example demonstrates how one would dirty both the element affected and the parent plug.

MObject exampleNode::inputAttr; // Non-dynamic multi-input attribute.
MObject exampleNode::outputAttr; // Non-dynamic multi-output attribute.
MStatus exampleNode::setDependentsDirty(MPlug const & inPlug,
MPlugArray & affectedPlugs)
{
if ( inPlug.attribute() != inputAttr ) {
return MS::kSuccess;
}
MPlug outArrayPlug(thisMObject(),outputAttr);
if (inPlug.isElement()) {
// First dirty the output output element first.
// Of course, dirty output element itself
MPlug elemPlug = outArrayPlug.elementByLogicalIndex(
inPlug.logicalIndex());
affectedPlugs.append(elemPlug);
// We also need to dirty the parent.
//
affectedPlugs.append(outArrayPlug);
} else {
// Mark the parent output plug as dirty.
//
affectedPlugs.append(outArrayPlug);
// Also visit each element.
//
unsigned int i,n = outArrayPlug.numElements();
for (i = 0; i < n; i++) {
MPlug elemPlug = outArrayPlug.elementByPhysicalIndex(i);
affectedPlugs.append(elemPlug);
}
}
return MS::kSuccess;
}

IMPORTANT NOTE: since the setDependentsDirty() method is called during dirty propagation, you must be careful not to perform any dependency graph computations from within the routine. Instead, if you want to know the value of a plug, use MDataBlock::outputValue() because it will not result in computation (and thus recursion). In general, the majority of {setDependentsDirty()} methods which users will implement should involve only fixed relationships. In the rare occurrence where you need to look at plug values, please heed the warning with {MDataBlock::outputValue()} and use plugs which contain values which you know to be up to date prior to the start of dirty propagation.

Parameters
[in]plugBeingDirtiedplug which is being set dirty by Maya
[in]affectedPlugsthe programmer should add any plugs which they want to set dirty to this list.
Returns
Status code
Status Codes:
  • MS::kSuccess Dirtying was successful
  • MS::kFailure Dirtying failed
Examples:
AbcImport/AlembicNode.cpp, AbcImport/AlembicNode.h, affectsNode/affectsNode.cpp, apiMeshShape/apiMeshShape.h, dx11Shader/dx11Shader.cpp, dx11Shader/dx11Shader.h, fileTexture/fileTexture.cpp, footPrintNode_AnimatedMaterial/footPrintNode_GeometryOverride_AnimatedMaterial.cpp, footPrintNode_GeometryOverride/footPrintNode_GeometryOverride.cpp, glslShader/GLSLShader.cpp, glslShader/GLSLShader.h, simpleEvaluationNode/simpleEvaluationNode.cpp, and testMTopologyEvaluator/testMTopologyEvaluator.h.
MStatus preEvaluation ( const MDGContext context,
const MEvaluationNode evaluationNode 
)
virtual

Prepare a node's internal state for threaded evaluation.

During the evaluation graph execution each node gets a chance to reset its internal states just before being evaluated.

This code has to be thread safe, non-blocking and work only on data owned by the node.

The timing of this callback is at the discretion of evaluation graph dependencies and individual evaluators. This means, it should be used purely to prepare this node for evaluation and no particular order should be assumed.

This call will most likely happen from a worker thread.

When using Evaluation Caching or VP2 Custom Caching, preEvaluation() is called as part of the evaluation process. This function is not called as part of the cache restore process because no evaluation takes place in that case.

Parameters
[in]contextContext in which the evaluation is happening. This should be respected and only internal state information pertaining to it should be modified.
[in]evaluationNodeEvaluation node which contains information about the dirty plugs that are about to be evaluated for the context. Should be only used to query information.
Examples:
apiMeshShape/apiMeshShape.h, footPrintNode/footPrintNode.cpp, simpleEvaluationNode/simpleEvaluationNode.cpp, simpleSkipNode/simpleSkipNode.cpp, and testMTopologyEvaluator/testMTopologyEvaluator.h.
MStatus postEvaluation ( const MDGContext context,
const MEvaluationNode evaluationNode,
PostEvaluationType  evalType 
)
virtual

Clean up node's internal state after threaded evaluation.

After the evaluation graph execution, each node gets a chance to update its internal states. For example, resetting draw state.

This code has to be thread safe, non-blocking and work only on data owned by the node.

This call will most likely happen from a worker thread.

When using Evaluation Caching or VP2 Custom Caching, postEvaluation() will be called as part of the evaluation process. In addition to its role in regular EM evaluation, it can also be used to notify VP2 to ensure correctness of VP2 cached buffers, and perform pull evaluation to ensure any internal secondary data is up to date after evaluation. Similar to preEvaluation() this function is not called as part of the cache restore process.

Parameters
[in]contextContext in which the evaluation happened. This should be respected and only internal state information pertaining to it should be modified.
[in]evaluationNodeEvaluation node which contains information about the dirty plugs that were evaluated for this context.
[in]evalTypekEvaluatedIndirectly: The node's compute function handled evaluation. kEvaluatedDirectly: Evaluation was performed externally and the results injected back into the node. This would happen in situations such as extracting values from an external cache. The node needs to update any additional internal state based on the new values. kLeaveDirty: Evaluation was performed without updating this node. Internal state should be updated to reflect that the node is dirty.
Examples:
apiMeshShape/apiMeshShape.h, footPrintNode_AnimatedMaterial/footPrintNode_GeometryOverride_AnimatedMaterial.cpp, and footPrintNode_GeometryOverride/footPrintNode_GeometryOverride.cpp.
void getCacheSetup ( const MEvaluationNode evalNode,
MNodeCacheDisablingInfo disablingInfo,
MNodeCacheSetupInfo cacheSetupInfo,
MObjectArray monitoredAttributes 
) const
virtual

Provide node-specific setup info for the Cached Playback system.

This method will be called at EM partitioning time. It works in one of two ways.

  • It can state that the node supports Cached Playback and background evaluation. In this case it can use the cacheSetupInfo to configure preferences and requirements
  • It can state that this node cannot work with Cached Playback enabled and will therefore cause Cached Playback to be disabled. In this case it can use the disablingInfo to provide additional info about why Cached Playback is disabled.

In case the answer depends on the value of attributes (for example, a node can have multiple modes, some of them working with caching and some of them not), the node can add the attributes to the monitored attribute list so they can be monitored in case the value changes.

By default, this method states that Cached Playback is supported, but does not request to be cached by default.

Note that regardless of the preferences expressed by a node, Caching Rules can always override the preferences from this method. Caching Rules always have the last world. This method simply indicates the built-in Evaluation Cache rule used by Maya's default Caching Modes that this node is to be cached. Other rules can ignore or override this behavior.

Parameters
[in]evalNodeThis node's evaluation node, contains animated plug information
[out]disablingInfoInformation about why the node disables Cached Playback to be reported to the user
[out]cacheSetupInfoPreferences and requirements this node has for Cached Playback
[out]monitoredAttributesAttributes impacting the behavior of this method that will be monitored for change

Reimplemented in MPxLocatorNode.

Examples:
apiMeshShape/apiMeshShape.cpp, apiMeshShape/apiMeshShape.h, simplePhysicsEngine/simplePhysicsEngine.cpp, simpleSimulationNode/simpleSimulationNode.cpp, and testMTopologyEvaluator/testMTopologyEvaluator.h.
void configCache ( const MEvaluationNode evalNode,
MCacheSchema schema 
) const
virtual

Defines the node's behavior when participating in Cached Playback.

This method will be called at EM partitioning time, after rules evaluation.

Parameters
[in]evalNodeThis node's evaluation node, contains animated plug information
[in,out]schemaSpecification about what attributes to cache
Examples:
simplePhysicsEngine/simplePhysicsEngine.cpp.
MTimeRange transformInvalidationRange ( const MPlug source,
const MTimeRange input 
) const
virtual

Override this method to register this node as an Invalidation-Range-Transformation kernel (IRT kernel) An IRT kernel node will change the invalidation time range for its downstream nodes For example, Dynamics-solver will transform invalidation time range [a,b] to [a,+inf) And Clip-Time-Editor will send out the invalidation range for each of the clip [a,b] to ( [t0+a,t0+b] U [t1+a,t1+b] U [t2+a,t2+b] U ...

)

Parameters
[in]sourceThe source plug in this node where the dirty propagation comes from
[in]inputThe incoming invalidation range
Returns
The output invalidation range for all the dependents of plug 'source'
Warning
You cannot do any evaluation in this function, because it can be called in dirty-propagation
Do *not* call MPxNode::transformInvalidationRange from your override method
Note
If a plugin node have invalidation-range-transformation *conditionally* Only transform the invalidation range when attribute 'enableIRT' is set The plugin should call MPxNode::transformInvalidationRange to signal it does not perform any IRT
Examples:
simplePhysicsEngine/simplePhysicsEngine.cpp, and simpleSimulationNode/simpleSimulationNode.cpp.
MStatus connectionMade ( const MPlug plug,
const MPlug otherPlug,
bool  asSrc 
)
virtual

This method gets called when connections are made to attributes of this node.

You should return kUnknownParameter to specify that maya should handle this connection or if you want maya to process the connection as well.

Only in very exceptional circumstances would you want to bypass maya's internal processing so when overriding this method the safest thing to do is to return the result from the base class as shown below.

MyChildNode::connectionMade(...)
{
if( MyChildNode understands the attribute )
doChildThing();
return MyParentNode::connectionMade(...);
}
MyParentNode::connectionMade(...)
{
if( MyParentNode understands the attribute )
doParentThing();
}
Parameters
[in]plugattribute on this node
[in]otherPlugattribute on other node
[in]asSrcis this plug a source of the connection
Returns
Status code
Status Codes:
  • MS::kSuccess Operation successful
  • MS::kUnknownParameter Unknown attribute
Examples:
apiMeshShape/apiMeshShape.cpp, apiMeshShape/apiMeshShape.h, and dx11Shader/dx11Shader.h.
MStatus connectionBroken ( const MPlug plug,
const MPlug otherPlug,
bool  asSrc 
)
virtual

This method gets called when connections are broken with attributes of this node.

You should return kUnknownParameter to specify that maya should handle this connection or if you want maya to process the connection as well.

Only in very exceptional circumstances would you want to bypass maya's internal processing so when overriding this method the safest thing to do is to return the result from the base class as shown below.

MyChildNode::connectionBroken(...)
{
if( MyChildNode understands the attribute )
doChildThing();
return MyParentNode::connectionBroken(...);
}
MyParentNode::connectionBroken(...)
{
if( MyParentNode understands the attribute )
doParentThing();
}
Parameters
[in]plugattribute on this node
[in]otherPlugattribute on other node
[in]asSrcis this plug a source of the connection
Returns
Status code
Status Codes:
  • MS::kSuccess Operation successful
  • MS::kUnknownParameter Unknown attribute
Examples:
apiMeshShape/apiMeshShape.cpp, and apiMeshShape/apiMeshShape.h.
MStatus dependsOn ( const MPlug plug,
const MPlug otherPlug,
bool &  depends 
) const
virtual

This method may be overridden by the user defined node.

It should only be required to override this on rare occasions.

This method determines whether a specific attribute depends on another attribute.

You should return kUnknownParameter to specify that Maya should determines the dependency (default).

This is mainly to define dependency of dynamic attributes, since attributeAffects does not work with dynamic attributes.

Parameters
[in]plugplug representing the attribute
[in]otherPlugplug representing the attribute to check for dependency
[out]dependsboolean telling whether there is a dependency between the two attributes
Returns
Status code
Status Codes:
  • MS::kSuccess Operation successful
  • MS::kUnknownParameter Unknown attribute
Examples:
dx11Shader/dx11Shader.h, and glslShader/GLSLShader.h.
bool isPassiveOutput ( const MPlug plug) const
virtual

This method may be overridden by the user defined node if it wants to provide output attributes which do not prevent value modifications to the destination attribute.

For example, output plugs on animation curve nodes are passive. This allows the attributes driven by the animation curves to be set to new values by the user.

Parameters
[in]plugplug representing output in question
Returns
true indicates passive
Examples:
AbcImport/AlembicNode.cpp, and AbcImport/AlembicNode.h.
MStatus shouldSave ( const MPlug plug,
bool &  isSaving 
)
virtual

This method may be overridden by the user defined node.

It should only be required to override this on rare occasions.

This method determines whether a specific attribute of this node should be written out during a file save. The default behavior is to only write the value if it differs from the default and is not being supplied by a connection. This behavior should be sufficient in most cases. This method is not called for ramp attributes since they should always be written.

Parameters
[in]plugplug representing the attribute to be saved
[in]isSavingboolean telling whether to save or not
Returns
Status code
Status Codes:
  • MS::kSuccess Operation successful
  • MS::kUnknownParameter Unknown attribute
Examples:
apiMeshShape/apiMeshShape.cpp, apiMeshShape/apiMeshShape.h, cgFx/cgfxShaderNode.cpp, cgFx/cgfxShaderNode.h, and exampleRampAttribute/exampleMRampAttribute.cpp.
MPlug passThroughToOne ( const MPlug plug) const
virtual

This method may be overridden by nodes that have a one-to-one relationship between an input attribute and a corresponding output attribute.

This method is used by Maya to perform the following capabilities:

  • When this node is deleted, the delete command will rewire the source of the input attribute to the destination of the output attribute if the source and destination are connected to nodes that are not deleted.
  • History traversal algorithms such as the bakePartialHistory command use this method to direct its traversal through a shape's construction history.
  • The base class Maya implementation of passThroughToAll will call this method if passThroughToAll returns false.
Parameters
[in]plugthe plug
Returns
The corresponding plug, or an empty plug if no corresponding plug exists
Examples:
customComponentTagNode/customComponentTagNode.cpp.
bool passThroughToMany ( const MPlug plug,
MPlugArray plugArray 
) const
virtual

This method is overridden by nodes that want to control the traversal behavior of some Maya search algorithms which traverse the history/future of shape nodes looking for directly related nodes.

In particular, the Artisan paint code uses this method when searching for paintable nodes, and the disk cache code uses this method when searching for upstream cacheFile nodes.

If this method is not implemented or returns false, the base class Maya implementation of this method calls passThroughToOne and returns the results of that call.

Parameters
[in]plugthe plug
[in]plugArraythe corresponding plugs
Returns
true if plug was handled, false to invoke base class implementation
MPxNode::Type type ( ) const
virtual

Returns the type of node that this is.

This is used to differentiate user defined nodes that are derived off different MPx base classes.

It is not necessary to override this method.

Returns
Type of the node

Reimplemented in MPxAssembly, MPxGeometryFilter, MPxManipContainer, MPxHwShaderNode, MPxTransform, MPxThreadedDeviceNode, MPxHardwareShader, MPxMotionPathNode, MPxIkSolverNode, MPxClientDeviceNode, MPxSurfaceShape, MPxEmitterNode, MPxSpringNode, MPxLocatorNode, MPxImagePlane, MPxObjectSet, MPxFieldNode, MPxBlendShape, MPxDeformerNode, MPxFluidEmitterNode, MPxSkinCluster, MPxCameraSet, and MPxParticleAttributeMapperNode.

bool isAbstractClass ( ) const
virtual

Override this class to return true if this node is an abstract node.

An abstract node can only be used as a base class. It cannot be created using the 'createNode' command.

It is not necessary to override this method.

Returns
true if the node is abstract.

Reimplemented in MPxPolyTrg.

bool isTrackingTopology ( ) const
virtual

Override this class to return true if this node wants to track topology.

This is necessary to enable certain optimizations done when geometry created by this node does not alter topology.

It is not necessary to override this method.

Returns
true if the node wants to track topology.
Examples:
topologyTrackingNode/topologyTrackingNode.cpp.
MStatus addAttribute ( const MObject attr)
static

This method adds a new attribute to a user defined node type during the type's initialization.

This method will only work during the static initialization method of the user defined node class. The initialization method is the one that is passed into MFnPlugin::registerNode. The attributes must first be created using one of the MFnAttribute classes, and can then be added using this method.

For compound attributes, the proper way to use this method is by calling it with the parent attribute. If a compound attribute is passed, this method will add all of its children. NOTE: A failure will occur if you attempt to call addAttribute() on the children of a compound attribute.

Parameters
[in]attrnew attribute to add
Returns
Status code
Status Codes:
  • MS::kSuccess Operation successful
  • MS::kInvalidParameter Attribute is invalid or already added or child of a compound attribute is being added before the parent
  • MS::kFailure Method was not called during the node's initialize routine
Examples:
exampleFalloff/smoothFalloffNode.cpp, geometryReplicator/geometryReplicator.cpp, gpuCache/gpuCacheShapeNode.cpp, sceneAssembly/adskPrepareRenderGlobals.cpp, sceneAssembly/assemblyDefinition.cpp, sceneAssembly/assemblyReference.cpp, simpleEvaluationDraw/simpleEvaluationDraw.cpp, transformDrawNode/transformDrawNode.cpp, and uiDrawManager/uiDrawManager.cpp.
MStatus inheritAttributesFrom ( const MString parentClassName)
static

This method allows a class of plugin node to inherit all of the attributes of a second class of plugin node.

This method will only work during the static initialization method of the user defined node class and must be called before any other attributes have been added. The initialization method is the one that is passed into MFnPlugin::registerNode.

A plugin node may only inherit attributes from one other class of plugin node. Attempting to call this method multiple times within a node's initialization method will result in an error.

Both node classes must be registered using the same MPxNode::Type.

Parameters
[in]parentClassNameclass of node to inherit attributes from
Returns
Status code
Status Codes:
  • MS::kSuccess Operation successful
  • MS::kInvalidParameter Class name is invalid or was registered with a different MPxNode::Type.
  • MS::kFailure Method was called outside of the node's initialize routine, or was called multiple times, or was called after attributes had already been added.
MStatus attributeAffects ( const MObject whenChanges,
const MObject isAffected 
)
static

This method specifies that a particular input attribute affects a specific output attribute.

This is required to make evaluation efficient. When an input changes, only the affected outputs will be computed. Output attributes cannot be keyable - if they are keyable, this method will fail.

This method must be called for every attribute dependency when initializing the node's attributes. The attributes must first be added using the MPxNode::addAttribute method. Failing to call this method will cause the node not to update when its inputs change. If there are no calls to this method in a node's initialization, then the compute method will never be called.

This method will only work during the static initialization method of the user defined node class. The initialization method is the one that is passed into MFnPlugin::registerNode. As a result, it does not work with dynamic attributes. For an alternate solution which handles dynamic as well as non-dynamic attributes refer to MPxNode::setDependentsDirty.

Parameters
[in]whenChangesinput attribute - MObject that points to an input attribute that has already been added
[in]isAffectedaffected output attribute - MObject that points to an output attribute that has already been added
Returns
Status code
Status Codes:
  • MS::kSuccess Operation successful
  • MS::kInvalidParameter At least one of the attributes is invalid or has not been added to this node using the addAttribute routine
  • MS::kFailure Method was not called during the node's initialize routine
MStatus attributeAffects ( const MObject whenChanges,
const MObject isAffected,
bool  affectsTopology 
)
static

This method is an extension to the other version of the attributeAffects method.

It allows specifying where the input attribute can affect the topology of the output attribute through this relationship.

Calling this method with the affectsTopology parameter set to true is the same as calling the 2-parameter version of this method. Calling it with false can enable certain optimizations done when geometry created by this node does not alter topology.

Parameters
[in]whenChangesinput attribute - MObject that points to an input attribute that has already been added
[in]isAffectedaffected output attribute - MObject that points to an output attribute that has already been added
[in]affectsTopologywhether this relationship affects topology or not
Returns
Status code
Status Codes:
  • MS::kSuccess Operation successful
  • MS::kInvalidParameter At least one of the attributes is invalid or has not been added to this node using the addAttribute routine
  • MS::kFailure Method was not called during the node's initialize routine
MStringArray getFilesToArchive ( bool  shortName = false,
bool  unresolvedName = false,
bool  markCouldBeImageSequence = false 
) const
virtual

Use this method to return all external files used by this node.

This file list will be used by the File > Archive zip feature, maya.exe -archive and the `file -q -list` mel command.

Only include files that exist.

If shortName is true, return just the filename portion of the path (can be obtained with MString::baseName()). Otherwise, return a full path.

If unresolvedName is true, return the path before any resolution has been done (i.e leave it as a relative path, include unexpanded environment variables, tildes, ".."s etc). Otherwise, resolve the file path and return an absolute path (to resolve with standard Maya path resolution, use MFileObject::resolvedFullName()).

Parameters
[in]shortNameIf true, only add the filename of the path
[in]unresolvedNameIf true, add paths before any resolution, rather than absolute paths.
[in]markCouldBeImageSequenceIf true, append an asterisk after any file path that could be an image sequence (note: only used by maya.exe -archive)
Returns
Array of file paths
Examples:
AbcImport/AlembicNode.h.
void getExternalContent ( MExternalContentInfoTable table) const
virtual

Returns the external content (files) that this node depends on.

The table populated by this method must include the location of all the content (files) used by this node, including those that do not exist. See MExternalContentInfoTable for details.

Keys used to add items to this table will be the same that get passed to setExternalContent through its MExternalContentLocationTable parameter to perform a batched change of content location.

When implementing getExternalContent, you are responsible for forwarding the call to the base class when it makes sense to do so, so that base classes can also add their external content to the table.

The default implementation does nothing.

Parameters
[out]tableContent information table that this method must populate.
Examples:
AbcImport/AlembicNode.cpp, AbcImport/AlembicNode.h, dx11Shader/dx11Shader.cpp, dx11Shader/dx11Shader.h, glslShader/GLSLShader.cpp, glslShader/GLSLShader.h, gpuCache/gpuCacheShapeNode.cpp, and sceneAssembly/assemblyDefinition.h.
bool addExternalContentForFileAttr ( MExternalContentInfoTable table,
const MObject attr 
) const

Adds content info to the specified table from a file path attribute.

This method is a helper for derived clases implementing getExternalContent(). It augments the external content info table passed in with an entry describing external content whose location is described by the specified attribute.

The method will not overwrite existing items, i.e. items with the same key. (attribute name). In this context, overwriting an item means the caller has called this function twice with the same attribute, or that two separate but identically named attributes were used. If replacing an entry is the desired effect, it is the caller's responsibility to erase the previous item first.

Parameters
[out]tableThe table in which the new entry will be added.
[in]attrThe attribute for which the plug value will be queried for a location.
Returns
true if an item was sucessfully added to the table. false if the attribute does not describe a non-empty location, or an item with the same key was already present in the table.
bool setExternalContentForFileAttr ( const MObject attr,
const MExternalContentLocationTable table 
)

Sets content info in the specified attribute from the table.

This method is a helper for derived clases implementing setExternalContent(). It assigns a value to a plug with the one from the table whose key is the same as the passed in attribute name.

The method will not write to the plug if the attribute is not found in the table.

Parameters
[in]attrThe attribute of the plug we want to write to.
[in]tableA table which may hold or not the value for a given plug.
Returns
true if the plug was successfully written to. false if no entry in the table was named after the attribute or if no plug was found.
void setExternalContent ( const MExternalContentLocationTable table)
virtual

Changes the location of external content in batch.

This is useful in the context of content relocation. This will be called while the scene is being loaded to apply path changes performed externally. Consequently, interaction with the rest of the scene must be kept to a minimum. It is however valid to call this method outside of scene loading contexts.

The keys in the map must be the same as the ones provided by the node in getExternalContent. The values are the new locations.

When implementing setExternalContent, you are responsible for forwarding the call to the base class when it makes sense to do so, so that base classes can also set their external content.

The default implementation does nothing.

Parameters
[in]tableKey->location table with new content locations.
Examples:
AbcImport/AlembicNode.cpp, AbcImport/AlembicNode.h, dx11Shader/dx11Shader.cpp, dx11Shader/dx11Shader.h, glslShader/GLSLShader.cpp, glslShader/GLSLShader.h, gpuCache/gpuCacheShapeNode.cpp, and sceneAssembly/assemblyDefinition.h.
const char * className ( )
static

Returns the name of this class.

Returns
The name of this class.
MTypeId typeId ( ) const
virtual

Returns the TYPEID of this node.

The TYPEID is a four byte identifier that uniquely identifies this type of node to the binary file format.

It is not necessary to override this method.

Returns
Type id of the node

Reimplemented in MPxAssembly.

Examples:
dx11Shader/dx11ConeAngleToHotspotConverter.h, dx11Shader/dx11Shader.h, and gpuCache/gpuCacheShapeNode.cpp.
MString typeName ( ) const
virtual

Returns the type name of this node.

The type name identifies the node type to the ASCII file format. It may also be used with the MEL command "createNode" to create a new node of this type.

It is not necessary to override this method.

Returns
Type name of the node

Reimplemented in MPxAssembly.

Examples:
exampleFalloff/smoothFalloffNode.h, and sceneAssembly/adskPrepareRenderGlobals.h.
MString name ( ) const
virtual

Returns the name of this particular instance of this class.

Each object in the dependency graph has a name. This name will be used by the UI and by MEL.

It is not necessary to override this method.

Returns
Name of the node

Reimplemented in MPxAssembly.

Examples:
topologyTrackingNode/topologyTrackingNode.cpp.
MObject thisMObject ( ) const
virtual

Returns the MObject associated with this user defined node.

This makes it possible to use MFnDependencyNode or to construct plugs to this node's attributes.

It is not necessary to override this method.

Returns
MObject handle for this node

Reimplemented in MPxAssembly, and MPxManipContainer.

MStatus setExistWithoutInConnections ( bool  flag)
virtual

This method specifies whether or not the node can exist without input connections.

If a node connected to this node is deleted resulting in no more input connections and if this flag is false, then this node will be deleted.

Parameters
[in]flagtrue if this node can exist without input connections, false otherwise
Status Codes:
  • MS::kSuccess operation successful
  • MS::kFailure this MPxNode has not been initialized properly. Make sure this method is not being called from the constructor.

Reimplemented in MPxAssembly.

bool existWithoutInConnections ( MStatus ReturnStatus = NULL) const
virtual

Determines whether or not this node can exist without input connections.

If a node connected to this node is deleted resulting in no more input connections and if this flag is false, then this node will be deleted.

Parameters
[out]ReturnStatusStatus code.
Returns
true is this node can exist without input connections, false otherwise
Status Codes:
  • MS::kSuccess operation successful
  • MS::kFailure this MPxNode has not been initialized properly. Make sure this method is not being called from the constructor.

Reimplemented in MPxAssembly.

MStatus setExistWithoutOutConnections ( bool  flag)
virtual

This method specifies whether or not the node can exist without output connections.

If a node connected to this node is deleted resulting in no more output connections and if this flag is false, then this node will be deleted.

Parameters
[in]flagtrue if this node can exist without output connections, false otherwise
Status Codes:
  • MS::kSuccess operation successful
  • MS::kFailure this MPxNode has not been initialized properly. Make sure this method is not being called from the constructor.

Reimplemented in MPxAssembly.

bool existWithoutOutConnections ( MStatus ReturnStatus = NULL) const
virtual

Determines whether or not this node can exist without output connections.

If a node connected to this node is deleted resulting in no more output connections and if this flag is false, then this node will be deleted.

Parameters
[out]ReturnStatusStatus code.
Returns
true is this node can exist without output connections, false otherwise
Status Codes:
  • MS::kSuccess operation successful
  • MS::kFailure this MPxNode has not been initialized properly. Make sure this method is not being called from the constructor.

Reimplemented in MPxAssembly.

MDataBlock forceCache ( )
protectedvirtual

USE _forceCache() IN SCRIPT.

Get the datablock for this node at the current evaluation context.

If there is no datablock then one will be created.

Note
This should be used only in places where fast access to the datablock outside of a compute is critical such as the transformUsing method of MPxSurfaceShape.
Warning
Do not override this method.
Returns
The datablock

Reimplemented in MPxAssembly.

MStatus setDoNotWrite ( bool  flag)
protectedvirtual

USE _setDoNotWrite() IN SCRIPT.

Use this method to mark the "do not write" state of this proxy node.

If set, this node will not be saved when the Maya model is written out.

NOTES: 1. Plug-in "requires" information will be written out with the model when saved. But a subsequent reload and resave of the file will cause these to go away. 2. If this node is a DAG and has a parent or children, the "do not write" flag of the parent or children will not be set. It is the developerメs responsibility to ensure that the resulting scene file is capable of being read in without errors due to unwritten nodes.

Parameters
[in]flagTrue if the user node should not be saved.

Reimplemented in MPxAssembly.

bool doNotWrite ( MStatus ReturnStatus = NULL) const
protectedvirtual

USE _doNotWrite() IN SCRIPT.

Use this method to query the "do not write" state of this proxy node.

True is returned if this node will not be saved when the Maya model is written out.

Parameters
[out]ReturnStatus

Reimplemented in MPxAssembly.

void setMPSafe ( bool  flag)
protectedvirtual

This method is obsolete.

Set a flag to specify if a user defined shading node is safe for multi-processor rendering.

[as of Maya 2019]

Deprecated:
Override schedulingType() to set thread safety instead.

For a shading node to be MP safe, it cannot access any shared global data and should only use attributes in the datablock to get input data and store output data.

NOTE: This should be called from the postConstructor() method for shading node plug-ins only. If a shading node is non-safe, then it will only be useful during single processor rendering.

Parameters
[in]flagTrue if user node is safe, false if non-safe.

Reimplemented in MPxAssembly.

MDataBlock forceCache ( const MDGContext context)
protectedvirtual

This method is obsolete.

If you are going to use the datablock for evaluation then you should make sure you have set your current context accordingly.

[as of Maya 2018]

Deprecated:
Use the method forceCache() instead. If needed, use MDGContextGuardto switch the context.

For example,

{ MDGContextGuard contextGuard( MDGContext( 3.0 ) ); MDataBlock timeBlock = myNode.forceCache(); do_some_time_stuff( timeBlock ); Context is automatically restored when Guard is destroyed }

Note
All other API methods accepting a context will make that context current for the duration of the call. This method is different in that it presumes you intend to further interact with the datablock, requiring a persistent change in context.
Warning
Do not override this method.
Parameters
[in]context
Returns
The datablock in given context
void _setMPSafe ( bool  flag)

This method is obsolete.

Set a flag to specify if a user defined shading node is safe for multi-processor rendering.

[as of Maya 2019]

Deprecated:
Override schedulingType() to set thread safety instead.

For a shading node to be MP safe, it cannot access any shared global data and should only use attributes in the datablock to get input data and store output data.

NOTE: This should be called from the postConstructor() method for shading node plug-ins only. If a shading node is non-safe, then it will only be useful during single processor rendering.

Parameters
[in]flagTrue if user node is safe, false if non-safe.
MDataBlock _forceCache ( const MDGContext context)

This method is obsolete.

Script use only, same as forceCache(const MDGContext& )

[as of Maya 2018]

Deprecated:
Use the method _forceCache() instead. If needed, use MDGContextGuard to switch the context.
bool getInternalValueInContext ( const MPlug plug,
MDataHandle dataHandle,
MDGContext ctx 
)
virtual

This method is obsolete.

[as of Maya 2018]

Deprecated:
Use the method getInternalValue(const MPlug&, MDataHandle&) instead. If needed, use MDGContext::current() to get the context.
Warning
This method's default behavior has changed from MAYA 2017 to MAYA 2018.
The default behaviour is to call the virtual method MPxNode::getInternalValue( const MPlug&, MDataHandle& ) for any context ( only for normal context ).
Parameters
[in]plugthe attribute that is being queried
[out]dataHandlethe dataHandle to store the attribute value
[in]ctxthe context the method is being evaluated in
Returns
  • true the attribute was placed in the datablock
  • false could not handle the specified attribute, pass this request to the default handler
bool setInternalValueInContext ( const MPlug plug,
const MDataHandle dataHandle,
MDGContext ctx 
)
virtual

This method is obsolete.

[as of Maya 2018]

Deprecated:
Use the method setInternalValue(const MPlug&, const MDataHandle&) instead. If needed, use MDGContext::current() to get the context.
Warning
This method's default behavior has changed from MAYA 2017 to MAYA 2018.
The default behaviour is to call the virtual method MPxNode::setInternalValue( const MPlug&, const MDataHandle& ) for any context ( only for normal context ).
Parameters
[in]plugthe attribute that is being set
[in]dataHandlethe dataHandle containing the value to set
[in]ctxthe context the method is being evaluated in
Returns
  • true the attribute was set
  • false could not handle the specified attribute, pass this request to the default handler
int internalArrayCount ( const MPlug plug,
const MDGContext ctx 
) const
virtual

This method is obsolete.

[as of Maya 2018]

Deprecated:
Use the method internalArrayCount(const MPlug&) instead.
Parameters
[in]plug
[in]ctx

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