MDagPath Class Reference
[OpenMaya - API module for common classes]

#include <MDagPath.h>

List of all members.

---

Detailed Description

DAG Path.

Provides methods for obtaining one or all Paths to a specified DAG Node, determining if a Path is valid and if two Paths are equivalent, obtaining the length, transform, and inclusive and exclusive matrices of a Path, as well as performing Path to Path assignment.

DAG Paths may be used as parameters to some methods in the DAG Node Function Set (MFnDagNode).

It is often useful to combine DAG Paths into DAG Path arrays (MDagPathArray).

Use this DAG Path Class to obtain and query Paths to DAG Nodes. A DAG path is a path from the world node to a particular object in the DAG.

If a DAG object is instanced, then an MDagPath is required to identify a particular instance. DAG paths are also required when doing world space transformations.

Use this class in conjunction with the DAG Iterator (MItDag), DAG Node Function Set (MFnDagNode) and DAG Path Array class (MDagPathArray) to query and edit the DAG.

Examples:

animExportUtil.cpp, animExportUtil.h, animInfoCmd.cpp, apiMeshShape.cpp, apiMeshShapeUI.cpp, apiSimpleShapeUI.cpp, cgfxEffectDef.cpp, cgfxEffectDef.h, cgfxShaderCmd.cpp, cgfxShaderNode.cpp, cgfxShaderNode.h, cleanPerFaceAssignmentCmd.cpp, closestPointCmd.cpp, closestPointOnCurveCmd.cpp, closestPointOnCurveNode.cpp, closestPointOnNurbsSurfaceCmd.cpp, closestTangentUAndDistance.cpp, closestTangentUAndDistance.h, clusterWeightFunction.cpp, componentScaleManip.cpp, convertEdgesToFacesCmd.cpp, convertVerticesToEdgesCmd.cpp, convertVerticesToFacesCmd.cpp, curvedArrowsNode.cpp, customAttrManip.cpp, cvColorNode.cpp, cvColorShader.cpp, cvExpandCmd.cpp, cvPosCmd.cpp, D3DGeometryItem.cpp, D3DGeometryItem.h, D3DResourceManager.cpp, D3DResourceManager.h, D3DViewportRenderer.cpp, D3DViewportRenderer.h, dagMessageCmd.cpp, exportJointClusterDataCmd.cpp, exportSkinClusterDataCmd.cpp, findTexturesPerPolygonCmd.cpp, footPrintManip.cpp, footPrintNode.cpp, getPointAndNormal.cpp, getPointAndNormal.h, GLSLShaderNode.cpp, GLSLShaderNode.h, hairCollisionSolver.cpp, helix2Cmd.cpp, helixTool.cpp, hlslShader.cpp, hwAnisotropicShader_NV20.cpp, hwColorPerVertexShader.cpp, hwDecalBumpShader_NV20.cpp, hwManagedTextureShader.cpp, hwPhongShader.cpp, hwPhongShader.h, hwReflectBumpShader_NV20.cpp, hwRefractReflectShader_NV20.cpp, hwToonShader_NV20.cpp, hwUnlitShader.h, instanceCallbackCmd.cpp, instancerListCmd.cpp, intersectCmd.cpp, intersectOnNurbsSurfaceCmd.cpp, lassoTool.cpp, lineManip.cpp, lineManip.h, lineManipContainer.cpp, lineManipContainer.h, listLightLinksCmd.cpp, listPolyHolesCmd.cpp, lockEvent.cpp, maTranslator.cpp, meshMapUtils.cpp, meshMapUtils.h, meshOpCmd.cpp, meshRemapCmd.h, meshRemapTool.cpp, meshReorderCmd.h, meshReorderTool.cpp, motionPathCmd.cpp, moveCurveCVsCmd.cpp, moveManip.cpp, moveNumericTool.cpp, moveTool.cpp, narrowPolyViewer.cpp, narrowPolyViewer.h, narrowPolyViewerCmd.cpp, narrowPolyViewerCmd.h, objExport.cpp, OpenGLViewportRenderer.cpp, OpenGLViewportRenderer.h, peltOverlapCmd.cpp, pnTrianglesNode.cpp, pointOnMeshCmd.cpp, pointOnMeshInfoNode.cpp, polyExporter.cpp, polyExporter.h, polyMessageCmd.cpp, polyModifierCmd.cpp, polyModifierCmd.h, polyRawExporter.cpp, polyRawExporter.h, polyRawWriter.cpp, polyRawWriter.h, polyWriter.cpp, polyWriter.h, polyX3DExporter.cpp, polyX3DExporter.h, polyX3DWriter.cpp, polyX3DWriter.h, quadricShape.cpp, renderViewRenderCmd.cpp, renderViewRenderRegionCmd.cpp, rotateManip.cpp, sampleCmd.cpp, sampleParticles.cpp, scanDagCmd.cpp, scanDagSyntax.cpp, ShapeMonitor.cpp, simpleEmitter.cpp, simpleEmitter.h, simpleSolverNode.cpp, spiralAnimCurveCmd.cpp, splitUVCmd.cpp, squareScaleManip.cpp, squareScaleManip.h, squareScaleManipContext.cpp, squareScaleManipContext.h, surfaceBumpManip.cpp, surfaceTwist.cpp, surfaceTwistCmd.cpp, swissArmyManip.cpp, torusField.cpp, torusField.h, translateCmd.cpp, and zoomCameraCmd.cpp.

Public Member Functions
	MDagPath ()
	MDagPath (const MDagPath &src)
virtual	~MDagPath ()
bool	hasFn (MFn::Type type, MStatus *ReturnStatus=NULL) const
MFn::Type	apiType (MStatus *ReturnStatus=NULL) const
bool	isValid (MStatus *ReturnStatus=NULL) const
MObject	node (MStatus *ReturnStatus=NULL) const
MObject	transform (MStatus *ReturnStatus=NULL) const
unsigned int	length (MStatus *ReturnStatus=NULL) const
MStatus	extendToShape ()
MStatus	extendToShapeDirectlyBelow (unsigned int)
MStatus	numberOfShapesDirectlyBelow (unsigned int &) const
MStatus	push (const MObject &child)
MStatus	pop (unsigned int num=1)
unsigned int	childCount (MStatus *ReturnStatus=NULL) const
MObject	child (unsigned int i, MStatus *ReturnStatus=NULL) const
MMatrix	inclusiveMatrix (MStatus *ReturnStatus=NULL) const
MMatrix	exclusiveMatrix (MStatus *ReturnStatus=NULL) const
MMatrix	inclusiveMatrixInverse (MStatus *ReturnStatus=NULL) const
MMatrix	exclusiveMatrixInverse (MStatus *ReturnStatus=NULL) const
MDagPath &	operator= (const MDagPath &src)
bool	operator== (const MDagPath &src) const
MStatus	set (const MDagPath &src)
unsigned int	pathCount (MStatus *ReturnStatus=NULL) const
MStatus	getPath (MDagPath &path, unsigned int i=0) const
MString	fullPathName (MStatus *ReturnStatus=NULL) const
MString	partialPathName (MStatus *ReturnStatus=NULL) const
bool	isInstanced (MStatus *ReturnStatus=NULL) const
unsigned int	instanceNumber (MStatus *ReturnStatus=NULL) const
Static Public Member Functions
static MStatus	getAllPathsTo (const MObject &node, MDagPathArray &pathArray)
static MStatus	getAPathTo (const MObject &node, MDagPath &path)
static MDagPath	getAPathTo (const MObject &node, MStatus *ReturnStatus=NULL)
	Obsolete.

---

Constructor & Destructor Documentation

MDagPath::MDagPath

(

)

Class Constructor.

Creates a DAG Path

MDagPath::MDagPath

(

const MDagPath &

src

)

Copy constructor. Duplicate the given path.

Parameters:

[in]

src

the path to be copied

MDagPath::~MDagPath

(

)

[virtual]

Class Destructor

No additional action.

---

Member Function Documentation

MStatus MDagPath::getAllPathsTo	(	const MObject &	node,
		MDagPathArray &	pathArray
	)			[static]

Determines all Paths to the specified DAG Node.

Parameters:

[in]	node	DAG Node for which Paths are determined
[out]	pathArray	Array containing all DAG Paths to the specified Node (implicit return)

Returns:

Status Code

Status Codes:

• MS::kSuccess Success
• MS::kInvalidParameter Invalid parameter passed for node - Node is not accessible, does not exist or is not a DAG Node
• MS::kFailure Unknown failure to determine Paths

MStatus MDagPath::getAPathTo	(	const MObject &	node,
		MDagPath &	path
	)			[static]

Determines the Path to the specified DAG Node. The Path returned is rooted at the World. If the object is instanced and has multiple paths, then the first one that is found is returned.

Parameters:

[in]	node	DAG Node for which Paths are determined
[out]	path	reference to the path of the specified DAG Node

Returns:

Status Code

Status Codes:

• MS::kSuccess Success
• MS::kInvalidParameter Invalid parameter passed for node - Node is not accessible, does not exist or is not a DAG Node
• MS::kFailure Unknown failure to determine Path

Examples:

animInfoCmd.cpp, closestPointCmd.cpp, dagMessageCmd.cpp, intersectCmd.cpp, maTranslator.cpp, polyMessageCmd.cpp, polyModifierCmd.cpp, and simpleSolverNode.cpp.

bool MDagPath::hasFn	(	MFn::Type	type,
		MStatus *	ReturnStatus = NULL
	)			const

Returns true if the object at the end of this DAG path supports the given function set.

If the object at the end of this DAG path is a transform node and has a child that is a shape, then that node will be checked as well. All function sets that take an MDagPath

Parameters:

[in]	type	function set type to check
[out]	ReturnStatus	status code

Returns:

Boolean value indicating whether the function set is supported

Status Codes:

• MS::kSuccess Success
• MS::kFailure Invalid object

Examples:

closestPointOnCurveCmd.cpp, cvExpandCmd.cpp, D3DResourceManager.cpp, D3DViewportRenderer.cpp, GLSLShaderNode.cpp, hwColorPerVertexShader.cpp, listLightLinksCmd.cpp, meshRemapTool.cpp, meshReorderTool.cpp, narrowPolyViewer.cpp, objExport.cpp, OpenGLViewportRenderer.cpp, pointOnMeshCmd.cpp, scanDagCmd.cpp, scanDagSyntax.cpp, surfaceTwist.cpp, and surfaceTwistCmd.cpp.

MFn::Type MDagPath::apiType

(

MStatus *

ReturnStatus = NULL

)

const

Returns the type of the object at the end of the path.

Parameters:

[out]

ReturnStatus

status code

Returns:

Type of the object

Status Codes:

• MS::kSuccess Success
• MS::kFailure Invalid object

Examples:

cleanPerFaceAssignmentCmd.cpp.

bool MDagPath::isValid

(

MStatus *

ReturnStatus = NULL

)

const

Determines if Path is valid.

Parameters:

[out]

ReturnStatus

status code

Returns:

True if valid

Status Codes:

• MS::kSuccess Success
• MS::kFailure Invalid object

Examples:

cgfxShaderNode.cpp, D3DResourceManager.cpp, D3DViewportRenderer.cpp, dagMessageCmd.cpp, GLSLShaderNode.cpp, instanceCallbackCmd.cpp, motionPathCmd.cpp, and OpenGLViewportRenderer.cpp.

MObject MDagPath::node

(

MStatus *

ReturnStatus = NULL

)

const

Retrieves the DAG Node for this DAG Path.

Parameters:

[out]

ReturnStatus

Status Code

Returns:

DAG Node for this DAG Path

Status Codes:

• MS::kSuccess Success
• MS::kFailure Invalid object or no node

Examples:

animExportUtil.cpp, blindDataShader.cpp, cgfxEffectDef.cpp, closestPointCmd.cpp, closestPointOnCurveCmd.cpp, componentScaleManip.cpp, D3DGeometryItem.cpp, dagMessageCmd.cpp, GLSLShaderNode.cpp, hwAnisotropicShader_NV20.cpp, hwColorPerVertexShader.cpp, hwManagedTextureShader.cpp, hwToonShader_NV20.cpp, listPolyHolesCmd.cpp, maTranslator.cpp, meshRemapTool.cpp, meshReorderTool.cpp, objExport.cpp, OpenGLViewportRenderer.cpp, pointOnMeshCmd.cpp, polyMessageCmd.cpp, polyModifierCmd.cpp, and splitUVCmd.cpp.

MObject MDagPath::transform

(

MStatus *

ReturnStatus = NULL

)

const

Retrieves the lowest Transform in the DAG Path.

Parameters:

[out]

ReturnStatus

Status Code

Returns:

Lowest Transform for this DAG Path

Status Codes:

• MS::kSuccess Success
• MS::kInvalidParameter This object has no transform (i.e. this is the world node)
• MS::kFailure Invalid object

Examples:

dagMessageCmd.cpp, scanDagCmd.cpp, scanDagSyntax.cpp, and spiralAnimCurveCmd.cpp.

unsigned int MDagPath::length

(

MStatus *

ReturnStatus = NULL

)

const

Determines the number of DAG Nodes in the Path not including the root.

Parameters:

[out]

ReturnStatus

status code

Returns:

Number of DAG Nodes not including the root

Status Codes:

• MS::kSuccess Success
• MS::kFailure Invalid object

Examples:

maTranslator.cpp, and ShapeMonitor.cpp.

MStatus MDagPath::extendToShape

(

)

If the object at the end of this path is a transform and there is a shape node directly beneath it in the hierarchy, then the path is extended to that geometry node.

NOTE: This method will fail if there multiple shapes below the transform.

Returns:

Status code

Status Codes:

• MS::kSuccess operation successful
• MS::kInvalidParameter DAG path does not lead to a transform or there is no geometry below it
• MS::kFailure the object is invalid

Examples:

cleanPerFaceAssignmentCmd.cpp, closestPointOnCurveCmd.cpp, findTexturesPerPolygonCmd.cpp, listLightLinksCmd.cpp, listPolyHolesCmd.cpp, meshOpCmd.cpp, meshRemapTool.cpp, pointOnMeshCmd.cpp, polyMessageCmd.cpp, polyModifierCmd.cpp, and splitUVCmd.cpp.

MStatus MDagPath::extendToShapeDirectlyBelow

(

unsigned int

index

)

This method is used if the end of the path is a transform and there are shapes directly below the transform. The shape to extend to is set by passing in an appropriate index parameter.

Use the numberOfShapesDirectlyBelow() method to determine how many shapes are below

Parameters:

[in]

index

contains the index of the shape to extend the path to

Returns:

Status code

Status Codes:

• MS::kSuccess operation successful
• MS::kInvalidParameter DAG path does not lead to a transform or there is no geometry below it
• MS::kFailure the object is invalid

MStatus MDagPath::numberOfShapesDirectlyBelow

(

unsigned int &

num

)

const

If the object at the end of this path is a transform, this method will return the number of shapes directly below the transform.

Parameters:

[in]

num

on success, this parameter will be set to the number of shapes directly underneath the transform

Returns:

Status code

Status Codes:

• MS::kSuccess operation successful
• MS::kInvalidParameter DAG path does not lead to a transform or there is no geometry below it
• MS::kFailure the object is invalid

MStatus MDagPath::push

(

const MObject &

child

)

Push an object onto the end of the path. The object must be a child of the object that is currently at the end of the path.

Parameters:

[in]

child

child object to push onto the path

Returns:

Status code

Status Codes:

• MS::kSuccess operation successful
• MS::kFailure unexpected error or invalid object
• MS::kInvalidParameter child is invalid or is not a child of the object at the end of this path

MStatus MDagPath::pop

(

unsigned int

num = 1

)

Pop the given number of objects off of the end of the path.

Parameters:

[in]

num

number of objects to pop off of the path

Returns:

Status code

Status Codes:

• MS::kSuccess operation successful
• MS::kInvalidParameter the number of objects to pop is greater than the length of the path
• MS::kFailure the object is invalid

Examples:

footPrintManip.cpp, lineManipContainer.cpp, maTranslator.cpp, narrowPolyViewer.cpp, ShapeMonitor.cpp, and swissArmyManip.cpp.

unsigned int MDagPath::childCount

(

MStatus *

ReturnStatus = NULL

)

const

Return the number of children that the object at the end of the path has.

Parameters:

[out]

ReturnStatus

status code

Returns:

The number of children

Status Codes:

• MS::kSuccess operation successful
• MS::kFailure invalid object

Examples:

animExportUtil.cpp, and OpenGLViewportRenderer.cpp.

MObject MDagPath::child	(	unsigned int	index,
		MStatus *	ReturnStatus = NULL
	)			const

Return the child object at the given index, where the parent is the object at the end of the path.

Parameters:

[in]	index	child's index
[out]	ReturnStatus	status code

Returns:

A handle to the child

Status Codes:

• MS::kSuccess operation successful
• MS::kInvalidParameter the index is out of range
• MS::kFailure the object is invalid

MMatrix MDagPath::inclusiveMatrix

(

MStatus *

ReturnStatus = NULL

)

const

Determines the inclusive matrix of the Path.

Parameters:

[out]

ReturnStatus

status code

Returns:

The matrix for all Transforms in the Path including the the end Node in the Path if it is a Transform

Status Codes:

• MS::kSuccess success
• MS::kFailure the object is invalid or it has a null path

Examples:

apiMeshShapeUI.cpp, apiSimpleShapeUI.cpp, cgfxShaderNode.cpp, closestPointCmd.cpp, closestPointOnNurbsSurfaceCmd.cpp, D3DResourceManager.cpp, D3DViewportRenderer.cpp, GLSLShaderNode.cpp, hwAnisotropicShader_NV20.cpp, hwReflectBumpShader_NV20.cpp, hwRefractReflectShader_NV20.cpp, hwToonShader_NV20.cpp, instancerListCmd.cpp, intersectOnNurbsSurfaceCmd.cpp, OpenGLViewportRenderer.cpp, sampleCmd.cpp, and sampleParticles.cpp.

MMatrix MDagPath::exclusiveMatrix

(

MStatus *

ReturnStatus = NULL

)

const

Determines the exclusive matrix of the Path.

Parameters:

[out]

ReturnStatus

status code

Returns:

The matrix for all transforms in the Path excluding the end Node in the Path if it is Transform

Status Codes:

• MS::kSuccess success
• MS::kFailure the object is invalid

MMatrix MDagPath::inclusiveMatrixInverse

(

MStatus *

ReturnStatus = NULL

)

const

Determines the inverse inclusive matrix of the Path.

Parameters:

[out]

ReturnStatus

status code

Returns:

The inverse of the matrix for all Transforms in the Path including the end Node in the Path if it is a Transform

Status Codes:

• MS::kSuccess success
• MS::kFailure the object is invalid

Examples:

closestPointOnNurbsSurfaceCmd.cpp, hwAnisotropicShader_NV20.cpp, hwDecalBumpShader_NV20.cpp, hwToonShader_NV20.cpp, and intersectOnNurbsSurfaceCmd.cpp.

MMatrix MDagPath::exclusiveMatrixInverse

(

MStatus *

ReturnStatus = NULL

)

const

Determines the inverse exclusive matrix of the Path.

Parameters:

[out]

ReturnStatus

status code

Returns:

The inverse of the matrix for all transforms in the Path excluding the end Node in the Path if it is Transform

Status Codes:

• MS::kSuccess success
• MS::kFailure the object is invalid

MDagPath & MDagPath::operator=

(

const MDagPath &

src

)

Assigns the DAG Path on the RHS of the operator to the DAG Path on the LHS.

Parameters:

[in]

src

the path to be copied

Returns:

A bitwise copy of the the DAG Path on the LHS

bool MDagPath::operator==

(

const MDagPath &

src

)

const

Determines if the DAG Path on the LHS of the operator is equal to the DAG Path on the RHS.

Parameters:

[in]

src

The path to be compared.

Returns:

True is the objects are equal

MStatus MDagPath::set

(

const MDagPath &

src

)

Sets this DAG Path equal to the specified DAG Path.

Parameters:

[in]

src

DAG Path to be copied.

Returns:

Status code

Status Codes:

• MS::kSuccess success
• MS::kFailure the object is invalid

unsigned int MDagPath::pathCount

(

MStatus *

ReturnStatus = NULL

)

const

Return the number of paths which make up this path.

Parameters:

[out]

ReturnStatus

status code

Returns:

The path count

Status Codes:

• MS::kSuccess success
• MS::kFailure the object is invalid

Examples:

maTranslator.cpp.

MStatus MDagPath::getPath	(	MDagPath &	path,
		unsigned int	i = 0
	)			const

Return the i'th path. The zero'th path is the top-most path and must be rooted by the world. Additional paths are paths in the underworld of the object at the end of the previous path (path i-1).

Parameters:

[out]	path	reference to the destination path
[in]	i	the index of the path to retrieve

Returns:

Status code

Status Codes:

• MS::kSuccess success
• MS::kFailure the object is invalid

Examples:

customAttrManip.cpp, lineManipContainer.cpp, and maTranslator.cpp.

MString MDagPath::fullPathName

(

MStatus *

ReturnStatus = NULL

)

const

Return a string representing the full path from the root of the dag to this object.

Parameters:

[out]

ReturnStatus

status code

Returns:

The full path name

Status Codes:

• MS::kSuccess success
• MS::kFailure the object is invalid

Examples:

cleanPerFaceAssignmentCmd.cpp, convertEdgesToFacesCmd.cpp, convertVerticesToEdgesCmd.cpp, convertVerticesToFacesCmd.cpp, D3DGeometryItem.cpp, dagMessageCmd.cpp, hwColorPerVertexShader.cpp, instanceCallbackCmd.cpp, instancerListCmd.cpp, listLightLinksCmd.cpp, objExport.cpp, OpenGLViewportRenderer.cpp, renderViewRenderCmd.cpp, renderViewRenderRegionCmd.cpp, scanDagCmd.cpp, and scanDagSyntax.cpp.

MString MDagPath::partialPathName

(

MStatus *

ReturnStatus = NULL

)

const

Return a string representing the partial path from the root of the dag to this object.

The partial path is the minimum path that is still unique. This string may contain wildcards.

Parameters:

[out]

ReturnStatus

status code

Returns:

The partial path name

Status Codes:

• MS::kSuccess success
• MS::kFailure the object is invalid

Examples:

cgfxShaderCmd.cpp, cgfxShaderNode.cpp, closestPointOnNurbsSurfaceCmd.cpp, exportJointClusterDataCmd.cpp, exportSkinClusterDataCmd.cpp, hwDecalBumpShader_NV20.cpp, hwReflectBumpShader_NV20.cpp, hwRefractReflectShader_NV20.cpp, hwToonShader_NV20.cpp, intersectOnNurbsSurfaceCmd.cpp, maTranslator.cpp, and narrowPolyViewer.cpp.

bool MDagPath::isInstanced

(

MStatus *

ReturnStatus = NULL

)

const

Returns true if the object at the end of the DAG path is instanced. It is instanced if there is more than one path to the node from the top of the DAG. Each instance of the node will be drawn separately in the view, but the geometry will be shared.

Parameters:

[out]

ReturnStatus

status code

Returns:

True if the DAG node at the end of the path is instanced

Status Codes:

• MS::kSuccess success
• MS::kFailure the object is invalid

Examples:

findTexturesPerPolygonCmd.cpp.

unsigned int MDagPath::instanceNumber

(

MStatus *

ReturnStatus = NULL

)

const

For an instanced object, this returns the instance number that this path represents in the DAG. The instance number can be used to determine which element of the world space array attributes of a DAG node to connect to get information regarding this instance.

Parameters:

[out]

ReturnStatus

status code

Returns:

The instance number represented by this path

Status Codes:

• MS::kSuccess success
• MS::kFailure the object is invalid

Examples:

cleanPerFaceAssignmentCmd.cpp, closestPointOnCurveCmd.cpp, cvColorShader.cpp, D3DViewportRenderer.cpp, findTexturesPerPolygonCmd.cpp, and pointOnMeshCmd.cpp.

MDagPath MDagPath::getAPathTo	(	const MObject &	node,
		MStatus *	ReturnStatus = NULL
	)			[static]

Obsolete.

This method is obsolete.

Deprecated:

The function signature was inconsistent with the rest of the API. Please use the other MDagPath::getAPathTo method instead.

Determines the Path to the specified DAG Node. The Path returned is rooted at the World. If the object is instanced and has multiple paths, then the first one that is found is returned.

Parameters:

[in]	node	DAG Node for which Paths are determined
[out]	ReturnStatus	Status Code

Returns:

Path to the specified Node

Status Codes:

• MS::kSuccess Success
• MS::kInvalidParameter Invalid parameter passed for object - Node is not accessible, does not exist or is not a DAG Node
• MS::kFailure Unknown failure to determine Path