MPxSurfaceShape Class Reference
[OpenMaya - API module for common classes, Proxy classes]

#include <MPxSurfaceShape.h>

Inheritance diagram for MPxSurfaceShape:

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Collaboration diagram for MPxSurfaceShape:

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List of all members.

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Detailed Description

Parent class of all user defined shapes.

MPxSurfaceShape is the parent class of all user defined shapes. User defined shapes are dependency nodes (and DAG nodes) which contain overridable drawing, selection, and component methods.

This class can be used to implement new kinds of shapes within Maya that can have selectable/manipulatable components and behave in a similar manner to the default shapes in maya.

The UI dependent aspects of the shape should be implemented in a class derived from MPxSurfaceShapeUI. This includes the drawing and interactive selection of the shape and any components that the shape implements.

Examples:

apiMeshShape.h, apiMeshShapeUI.cpp, and quadricShape.cpp.

Public Types
enum	MVertexCachingMode { kNoPointCaching, kSavePoints, kRestorePoints, kUpdatePoints }
	Vertex caching modes. More...
enum	MVertexOffsetMode { kNormal, kUTangent, kVTangent, kUVNTriad }
	Vertex offset modes. More...
enum	MatchResult {    kMatchOk, kMatchNone, kMatchTooMany, kMatchInvalidName,    kMatchInvalidAttribute, kMatchInvalidAttributeIndex, kMatchInvalidAttributeRange, kMatchInvalidAttributeDim }
	Return values for the matchComponent() method. More...
enum	MChildChanged { kObjectChanged, kBoundingBoxChanged }
	Scope of change. More...
Public Member Functions
	MPxSurfaceShape ()
virtual	~MPxSurfaceShape ()
virtual MPxNode::Type	type () const
virtual bool	isBounded () const
virtual MBoundingBox	boundingBox () const
virtual void	transformUsing (const MMatrix &mat, const MObjectArray &componentList)
virtual void	transformUsing (const MMatrix &mat, const MObjectArray &componentList, MVertexCachingMode cachingMode, MPointArray *pointCache)
virtual void	tweakUsing (const MMatrix &mat, const MObjectArray &componentList, MVertexCachingMode cachingMode, MPointArray *pointCache, MArrayDataHandle &handle)
bool	convertToTweakNodePlug (MPlug &plug) const
virtual bool	vertexOffsetDirection (MObject &component, MVectorArray &direction, MVertexOffsetMode mode, bool normalize)
virtual MObject	newControlPointComponent () const
virtual void	componentToPlugs (MObject &component, MSelectionList &selectionList) const
virtual bool	match (const MSelectionMask &mask, const MObjectArray &componentList) const
virtual MatchResult	matchComponent (const MSelectionList &item, const MAttributeSpecArray &spec, MSelectionList &list)
virtual MObject	createFullVertexGroup () const
virtual bool	deleteComponents (const MObjectArray &componentList, MDoubleArray &undoInfo)
virtual bool	undeleteComponents (const MObjectArray &componentList, MDoubleArray &undoInfo)
virtual MObject	localShapeInAttr () const
virtual MObject	localShapeOutAttr () const
virtual MObject	worldShapeOutAttr () const
virtual MObject	cachedShapeAttr () const
virtual MObject	geometryData () const
virtual void	closestPoint (const MPoint &toThisPoint, MPoint &theClosestPoint, double tolerance)
virtual bool	pointAtParm (const MPoint &atThisParm, MPoint &evaluatedPoint)
virtual MPxGeometryIterator *	geometryIteratorSetup (MObjectArray &, MObject &, bool forReadOnly=false)
virtual bool	acceptsGeometryIterator (bool writeable=true)
virtual bool	acceptsGeometryIterator (MObject &, bool writeable=true, bool forReadOnly=false)
MObjectArray	activeComponents () const
bool	hasActiveComponents () const
void	childChanged (MChildChanged=kObjectChanged)
bool	isRenderable () const
void	setRenderable (bool)
MMatrix	getWorldMatrix (MDataBlock &, unsigned int) const
Static Public Attributes
static MObject	mControlPoints
	Control points for the derived shapes.
static MObject	mControlValueX
	X value of a control point.
static MObject	mControlValueY
	Y value of a control point.
static MObject	mControlValueZ
	Z value of a control point.
static MObject	nodeBoundingBox
	bounding box attribute
static MObject	nodeBoundingBoxMin
	bounding box minimum point
static MObject	nodeBoundingBoxMinX
	X component of boundingBoxMin.
static MObject	nodeBoundingBoxMinY
	Y component of boundingBoxMin.
static MObject	nodeBoundingBoxMinZ
	Z component of boundingBoxMin.
static MObject	nodeBoundingBoxMax
	bounding box maximum point
static MObject	nodeBoundingBoxMaxX
	X component of boundingBoxMax.
static MObject	nodeBoundingBoxMaxY
	Y component of boundingBoxMax.
static MObject	nodeBoundingBoxMaxZ
	Z component of boundingBoxMax.
static MObject	nodeBoundingBoxSize
	bounding box size vector
static MObject	nodeBoundingBoxSizeX
	X component of boundingBoxSize.
static MObject	nodeBoundingBoxSizeY
	Y component of boundingBoxSize.
static MObject	nodeBoundingBoxSizeZ
	Z component of boundingBoxSize.
static MObject	center
	object center attribute
static MObject	boundingBoxCenterX
	X component of boundingBoxCenter.
static MObject	boundingBoxCenterY
	Y component of boundingBoxCenter.
static MObject	boundingBoxCenterZ
	Z component of boundingBoxCenter.
static MObject	matrix
	matrix attribute
static MObject	inverseMatrix
	inverse matrix attribute
static MObject	worldMatrix
	world matrix attribute
static MObject	worldInverseMatrix
	inverse world matrix attribute
static MObject	parentMatrix
	parent matrix attribute
static MObject	parentInverseMatrix
	inverse parent matrix attribute
static MObject	visibility
	visibility attribute
static MObject	intermediateObject
	intermediate object attribute
static MObject	isTemplated
	template attribute
static MObject	instObjGroups
	instances object group info attribute
static MObject	objectGroups
	object groups attributes
static MObject	objectGrpCompList
	component in object groups attribute
static MObject	objectGroupId
	group id attribute
static MObject	objectGroupColor
	group id attribute
static MObject	useObjectColor
	controls choice of wireframe dormant object color
static MObject	objectColor
	the per object dormant wireframe color

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Member Enumeration Documentation

enum MPxSurfaceShape::MVertexCachingMode

Vertex caching modes.

Enumerator:

kNoPointCaching	No point caching.
kSavePoints	Points should be saved for undo in the point cache.
kRestorePoints	Points should be restored from the point cache.
kUpdatePoints	Update the points.

enum MPxSurfaceShape::MVertexOffsetMode

Vertex offset modes.

Enumerator:

kNormal	Move in normal direction.
kUTangent	Move in u tangent direction.
kVTangent	Move in v tangent direction.
kUVNTriad	Calculate u, v, and normal offsets.

enum MPxSurfaceShape::MatchResult

Return values for the matchComponent() method.

Enumerator:

kMatchOk	The component was matched without error.
kMatchNone	No component was matched.
kMatchTooMany	Not used.
kMatchInvalidName	One of the names in the attribute specification was not valid.
kMatchInvalidAttribute	Not used.
kMatchInvalidAttributeIndex	The attribute specification contained an index for a non-array attribute.
kMatchInvalidAttributeRange	An attribute index was out of range.
kMatchInvalidAttributeDim	The attribute specification provided the wrong number of dimensions for an attribute.

enum MPxSurfaceShape::MChildChanged

Scope of change.

Enumerator:

kObjectChanged	Object geometry changed. Internal caches need to be updated.
kBoundingBoxChanged	Object geometry is unchanged but its bounding box has changed. This might happen if the object was moved or an offset changed.

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Constructor & Destructor Documentation

MPxSurfaceShape::MPxSurfaceShape

(

)

Class constructor.

Any calls the MPxSurfaceShape methods must be done in the postConstructor method and not here.

MPxSurfaceShape::~MPxSurfaceShape

(

)

[virtual]

Class destructor.

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Member Function Documentation

MPxNode::Type MPxSurfaceShape::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 (MPxNode::kSurfaceShape)

Reimplemented from MPxNode.

bool MPxSurfaceShape::isBounded

(

)

const [virtual]

This method should be overridden to return true if the user supplies a bounding box routine. Supplying a bounding box routine makes refresh and selection more efficient.

Returns:

A boolean value indicating whether a bounding box routine has been supplied

Examples:

apiMeshShape.h, and quadricShape.cpp.

MBoundingBox MPxSurfaceShape::boundingBox

(

)

const [virtual]

This method should be overridden to return a bounding box for the shape. If this method is overridden, then MPxSurfaceShape::isBounded should also be overridden to return true.

Returns:

The bounding box of the shape

Examples:

apiMeshShape.h, apiMeshShapeUI.cpp, and quadricShape.cpp.

void MPxSurfaceShape::transformUsing	(	const MMatrix &	matrix,
		const MObjectArray &	componentList
	)			[virtual]

Transform the given components using the specified transformation matrix. This method should be overridden if the shape supports components that can be transformed using maya's move, scale, and rotate tools.

Parameters:

[in]	matrix	the matrix representing the transformation that is to be applied to the components
[in]	componentList	a list of components to be tranformed. If the list is empty, it indicates that every point in the geometry should be transformed.

Reimplemented in MPxComponentShape.

Examples:

apiMeshShape.h.

void MPxSurfaceShape::transformUsing	(	const MMatrix &	mat,
		const MObjectArray &	componentList,
		MVertexCachingMode	cachingMode,
		MPointArray *	pointCache
	)			[virtual]

Transform the given components using the specified transformation matrix. This method should be overridden if the shape supports components that can be transformed using maya's move, scale, and rotate tools.

Parameters:

[in]	mat	the matrix representing the transformation that is to be applied to the components
[in]	componentList	a list of components to be transformed. If the list is empty, it indicates that every point in the geometry should be transformed.
[in]	cachingMode	whether the points should be cached in the pointCache argument, or restored from the pointCache
[in]	pointCache	used to store for undo and restore points during undo

Reimplemented in MPxComponentShape.

void MPxSurfaceShape::tweakUsing	(	const MMatrix &	mat,
		const MObjectArray &	componentList,
		MVertexCachingMode	cachingMode,
		MPointArray *	pointCache,
		MArrayDataHandle &	handle
	)			[virtual]

Transform the given components using the specified transformation matrix. This method should be overridden if the shape supports components that can be transformed using maya's move, scale, and rotate tools. This method is called when the shape has history & connected to a tweak node. The most common reason why the shape would be connected to a tweak node is if it is being deformed. When a shape is connected to a tweak node, transformations applied to the points are placed in the tweak node rather than in the shape itself.

Parameters:

[in]	mat	the matrix representing the transformation that is to be applied to the components
[in]	componentList	a list of components to be tranformed. If the list is empty, it indicates that every point in the geometry should be transformed.
[in]	cachingMode	whether the points should be cached in the pointCache argument, or restored from the pointCache
[in]	pointCache	used to store for undo and restore points during undo
[in]	handle	array data handle where the tweaks are stored

Examples:

apiMeshShape.h.

bool MPxSurfaceShape::convertToTweakNodePlug

(

MPlug &

plug

)

const

Check if a tweak node is connected to this node. If it is, then reset the supplied plug to contain the controlPoints attribute on the tweak node.

Parameters:

[in]

plug

plug which will be set to point to the associated tweak node plug if a tweak node is connected

Returns:

true if a tweak node was found, false if the plug was unchanged

bool MPxSurfaceShape::vertexOffsetDirection	(	MObject &	component,
		MVectorArray &	direction,
		MVertexOffsetMode	mode,
		bool	normalize
	)			[virtual]

This method should be overridden if the shape supports components that can be moved in the direction of the normal or UV's using the move vertex normal tool.

This method should calculate the offset direction for a vertex components. The direction vector array is an array of offsets corresponding to the elements in the component. The mode argument specifies the type of movement that is being performed.

The default for this method is to return false, i.e. no support for move normal tool.

Parameters:

[in]	component
[in]	direction
[in]	mode	The type of vertex movement

• mode = 0 -> normal
• mode = 1 -> U
• mode = 2 -> V
• mode = 3 -> UVN triad

Parameters:

[in]

normalize

specifies whether the offset vectors should be normalized

Returns:

true if the shape supports the current mode, false if the shape cannot do the requested vertex move

Examples:

apiMeshShape.h.

MObject MPxSurfaceShape::newControlPointComponent

(

)

const [virtual]

The default action of this method is to return an MFnSingleIndexedComponent (of type MFn::kMeshVertComponent) in order to support rigid skinning binds.

This method can be overriden to support other types of components such as MFnDoubleIndexedComponent and MFnTripleIndexedComponent and should return a new component of that type. The types allowed are those listed in the create() method docs for each MFn*IndexedComponent.

No argument is required.

The skinning code handles the deallocation of the new component.

Returns:

The new component

void MPxSurfaceShape::componentToPlugs	(	MObject &	component,
		MSelectionList &	list
	)			const [virtual]

Converts the given component into a selection list of plugs. This method is used to associate a shapes components into the corresponding attributes (plugs) within the shape. For example, it gets called by the translate manipulator to determine which attributes should be driven by the manipulator, and by the setKeyframe command to determine where to connect animCurves for components.

This method should be overridden if the shape supports components that can be selected and moved in Maya.

Parameters:

[in]	component	the component to be converted
[in]	list	a selection list where the plug should be added

Reimplemented in MPxComponentShape.

Examples:

apiMeshShape.h.

bool MPxSurfaceShape::match	(	const MSelectionMask &	mask,
		const MObjectArray &	componentList
	)			const [virtual]

This method is used to check for matches between a selection type (or mask) and a given component. If your shape has components representing attributes then this method is used to match up your components with selection masks.

This is used by sets and deformers to make sure that the selected components fall into the "vertex only" category. This is useful when you want to make sure that only a particular component can be deformed.

Parameters:

[in]	mask	the selection mask to test against
[in]	componentList	a list of components to be tested

Returns:

• true the match was successfull
• false the match failed

Reimplemented in MPxComponentShape.

Examples:

apiMeshShape.h.

MPxSurfaceShape::MatchResult MPxSurfaceShape::matchComponent	(	const MSelectionList &	item,
		const MAttributeSpecArray &	spec,
		MSelectionList &	list
	)			[virtual]

This method is used to convert the string representation of a component into a component object and to validate that the indices.

This method should be overridden if the shape has components.

Parameters:

[in]	item	DAG selection item for the object being matched
[in]	spec	attribute specification object
[in]	list	list to add components to

Returns:

The component match result

Examples:

apiMeshShape.cpp, and apiMeshShape.h.

MObject MPxSurfaceShape::createFullVertexGroup

(

)

const [virtual]

This method is used to create a component containing every vertex/CV in the object.

This method is supposed to return non-NULL only if the dag object contains vertices/CVs (control points), so derived classes that do should override this method.

Eg: use MFnSingleIndexedComponent::setCompleteData( numVertices ) to specify that a component represents all the vertices of the shape.

Returns:

A component containing all of the vertices in the shape.

Reimplemented in MPxComponentShape.

Examples:

apiMeshShape.h.

bool MPxSurfaceShape::deleteComponents	(	const MObjectArray &	componentList,
		MDoubleArray &	undoInfo
	)			[virtual]

This method should be overridden if the shape is to support deletion of components. A list of components to be deleted will be passed in as well as an array of doubles where information about each deleted component can be stored for undo purposes. A typical use for this array is to store knot values or weights for control points that are deleted.

Parameters:

[in]	componentList	List of components to be deleted
[in]	undoInfo	Values used for undo purposes

Returns:

true if this method was successful, false otherwise

bool MPxSurfaceShape::undeleteComponents	(	const MObjectArray &	componentList,
		MDoubleArray &	undoInfo
	)			[virtual]

This method should be overridden if the shape is to support undeletion of components. A list of components to be deleted will be passed in as well as an array of doubles where information about each deleted component is stored for undo purposes. A typical use for this array is to store knot values or weights for control points that are deleted.

Parameters:

[in]	componentList	List of components that were deleted
[in]	undoInfo	Values used for undo purposes

Returns:

true if this method was successful, false otherwise

MObject MPxSurfaceShape::localShapeInAttr

(

)

const [virtual]

Returns the input attribute of the shape. This method will be called by Maya to determine if the shape has construction history.

Returns:

The input attribute

Reimplemented in MPxComponentShape.

Examples:

apiMeshShape.h.

MObject MPxSurfaceShape::localShapeOutAttr

(

)

const [virtual]

Returns the local output attribute of the shape.

Returns:

The output attribute

Examples:

apiMeshShape.h.

MObject MPxSurfaceShape::worldShapeOutAttr

(

)

const [virtual]

Returns the world space output attribute of the shape.

Returns:

The world space output attribute

Examples:

apiMeshShape.h.

MObject MPxSurfaceShape::cachedShapeAttr

(

)

const [virtual]

Returns the cached shape attribute of the shape.

Returns:

The attribute that stores the cached shape

Examples:

apiMeshShape.h.

MObject MPxSurfaceShape::geometryData

(

)

const [virtual]

Returns the geometry data of the shape. The geometry data must be derived from the MPxGeometryData class.

The data is used by Maya to add, edit and query component grouping (set) information for the shape. This set information is stored and managed by Maya's shape base class, geometryShape.

Returns:

The geometry data of the shape

Examples:

apiMeshShape.h.

void MPxSurfaceShape::closestPoint	(	const MPoint &	toThisPoint,
		MPoint &	theClosestPoint,
		double	tolerance
	)			[virtual]

This method is used by Maya in functions (such as select) that require closest point information from your surface.

Parameters:

[in]	toThisPoint	the point to test against
[out]	theClosestPoint	the closest point on your surface tolerance tolerance to use in your calculations

Examples:

apiMeshShape.h.

bool MPxSurfaceShape::pointAtParm	(	const MPoint &	atThisParm,
		MPoint &	evaluatedPoint
	)			[virtual]

This method is used by Maya in functions (such as select) that require point at parameter values. This only makes sense for parametric surfaces such as NURBS.

Parameters:

[in]	atThisParm	the parameter to check
[out]	evaluatedPoint	the surface point

Returns:

true if a point was found, false otherwise

MPxGeometryIterator * MPxSurfaceShape::geometryIteratorSetup	(	MObjectArray &	componentList,
		MObject &	components,
		bool	forReadOnly = false
	)			[virtual]

This method should be overridden by the user to return a geometry iterator compatible with the user's geometry. A geometry iterator is used for iterating over the components of a shape, such as the vertices of a mesh, in a generic manner.

The components to be iterated over are passed to this function in on of two ways, as a list of components, or as a single component. Only one of these arguments is used at any particular time.

Parameters:

[in]	componentList	a list of components to be iterated over
[in]	components	the components to be iterated over
[in]	forReadOnly	specifies whether the iterator is for read-only

Returns:

The component match result

Examples:

apiMeshShape.h, and apiSimpleShape.h.

bool MPxSurfaceShape::acceptsGeometryIterator

(

bool

writeable = true

)

[virtual]

If the shape can supply a component iterator then then this method should be overridden to return true. The default is to return false.

Parameters:

[in]

writeable

is this component type writable by an iterator

Returns:

• true the shape can supply an iterator
• false the shape cannot supply an iterator

Examples:

apiMeshShape.h, and apiSimpleShape.h.

bool MPxSurfaceShape::acceptsGeometryIterator	(	MObject &	component,
		bool	writeable = true,
		bool	forReadOnly = false
	)			[virtual]

If the shape can supply a component iterator then then this method should be overridden to return true. The default is to return false. The component argument can be used to when the shape has multiple components and not all of them can be iterator over.

Parameters:

[in]	component	the component to test
[in]	writeable	is this component type writable by an iterator
[in]	forReadOnly	is this component type readable by an iterator

Returns:

• true the shape can supply an iterator
• false the shape cannot supply an iterator

MObjectArray MPxSurfaceShape::activeComponents

(

)

const

Returns a list of active (selected) components for the shape.

Returns:

An array of active components

bool MPxSurfaceShape::hasActiveComponents

(

)

const

This method is used to determine whether or not the shape has active (selected) components.

Returns:

• true there are active components
• false there are no active components

void MPxSurfaceShape::childChanged

(

MChildChanged

state = kObjectChanged

)

This method can be used to trigger the shape to recalculate its bounding box.

Parameters:

[in]

state

the type of change that has occurred

bool MPxSurfaceShape::isRenderable

(

)

const

Returns true if the shape is a renderable shape. Making a shape renderable allows the shape to have shading group assignments.

Returns:

• true the shape is renderable
• false the shape is not renderable

void MPxSurfaceShape::setRenderable

(

bool

flag

)

Specifies whether the shape is a renderable shape. Making a shape renderable allows the shape to have shading group assignments.

Parameters:

[in]

flag

true if the shape is to be renderable, false otherwise

MMatrix MPxSurfaceShape::getWorldMatrix	(	MDataBlock &	block,
		unsigned int	instanceGeom
	)			const

Returns MMatrix which takes a point from local object space to world space.

Parameters:

[in]	block	a MDataBlock
[in]	instanceGeom	the instance this MPxSurfaceShape corresponds to