MPxGeometryIterator Class Reference

This reference page is linked to from the following overview topics: Components.

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Detailed Description

Base class for user defined geometry iterators.

This is the base class for user defined geometry iterators. Geometry iterator allow iterating over components in geometry in a geometry independent manner. This base class defines the interface to be used by maya when a generic component iteration is required.

This class is used in conjunction with MPxSurfaceShape to provide an iterator for components in a user defined shape. Also this method can is used by MPxGeometryData to provide an iterator over geometry that is passed through DG connections.

The main methods to override in this class are point and setPoint. The reset, isDone, and next methods have a default implementation and should only be overridden if the component being iterator on is not a single indexed component type.

The iterator works in two modes, over components or over all elements in some geometry. If the components passed into the constructors are null or empty then the iteration is meant to be over the entire object.

Examples:

apiMeshData.cpp, apiMeshData.h, apiMeshIterator.cpp, apiMeshIterator.h, apiMeshShape.cpp, apiMeshShape.h, apiSimpleShape.cpp, apiSimpleShape.h, apiSimpleShapeIterator.cpp, and apiSimpleShapeIterator.h.

#include <MPxGeometryIterator.h>

List of all members.

Public Member Functions
	MPxGeometryIterator (void *userGeometry, MObjectArray &components)
	Class constructor.
	MPxGeometryIterator (void *userGeometry, MObject &components)
	Class constructor.
virtual	~MPxGeometryIterator ()
	Class destructor.
virtual bool	isDone () const
	Indicates if all the items have been traversed yet.
virtual void	next ()
	Advances to the next component. Search for all occurrences
virtual void	reset ()
	Resets the iterator to the start of the components so that another pass over them may be made.
virtual void	component (MObject &component)
	Returns a component for the current item in the iteration.
virtual bool	hasPoints () const
	Indicates whether the underlying geometry has point data.
virtual int	iteratorCount () const
	Returns an estimate of how many items will be iterated over.
virtual MPoint	point () const
	Returns the current component's positional data.
virtual void	setPoint (const MPoint &) const
	Sets the current component's positional data.
virtual int	setPointGetNext (MPoint &)
	Sets the current component's positional data, gets the next point.
virtual int	index () const
	Returns a unique index for the current item in the iteration.
virtual bool	hasNormals () const
	Indicates whether the underlying geometry has normals.
virtual int	indexUnsimplified () const
	Returns a unique index for the current item in the iteration Rather than being the iterator index this is the index for the actual item when simplification is skipping items.
int	currentPoint () const
	Returns the index that is being iterated on.
void	setCurrentPoint (int)
	Set the current index of the iteration.
int	maxPoints () const
	Returns the largest index that will be iterated over.
void	setMaxPoints (int)
	Sets the largest index that will be iterated over.
void	setObject (MPxSurfaceShape &)
	Optional method to set a shape object to iterate over to allow tweaking of the shape's history (input geometry). Search for all occurrences
void *	geometry () const
	Returns a pointer to the geometry that this iterator is iterating over.
Static Public Member Functions
static const char *	className ()
	Returns the name of this class. Search for all occurrences

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Constructor & Destructor Documentation

MPxGeometryIterator	(	void *	userGeometry,
		MObjectArray &	components
	)

Class constructor.

The components can be NULL if the iteration is to be over all elements in the geometry.

Parameters:

[in]	userGeometry	the geometry that will be iterated over
[in]	components	the (optional) list of components to iterate over

MPxGeometryIterator	(	void *	userGeometry,
		MObject &	components
	)

Class constructor.

The components can be NULL if the iteration is to be over all elements in the geometry.

Parameters:

[in]	userGeometry	the geometry that will be iterated over
[in]	components	the (optional) components to iterate over

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Member Function Documentation

bool isDone

(

)

const [virtual]

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Indicates if all the items have been traversed yet.

Returns:

• true the iterator has no more elements to traverse
• false the iterator is not finished traversing

void component

(

MObject &

component

)

[virtual]

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Returns a component for the current item in the iteration.

Parameters:

[out]

component

storage for the returned component

bool hasPoints

(

)

const [virtual]

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Indicates whether the underlying geometry has point data.

Returns:

• true the geometry has point data
• false the geometry does not have point data

Examples:

apiMeshIterator.h, and apiSimpleShapeIterator.h.

int iteratorCount

(

)

const [virtual]

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Returns an estimate of how many items will be iterated over.

Returns:

The iterator count

Examples:

apiMeshIterator.h, and apiSimpleShapeIterator.h.

MPoint point

(

)

const [virtual]

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Returns the current component's positional data.

Returns:

The current point being iterated over

Examples:

apiMeshIterator.h, and apiSimpleShapeIterator.h.

void setPoint

(

const MPoint &

point

)

const [virtual]

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Sets the current component's positional data.

Parameters:

[in]

point

the new positional value to set

Examples:

apiMeshIterator.h, and apiSimpleShapeIterator.h.

int setPointGetNext

(

MPoint &

point

)

[virtual]

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Sets the current component's positional data, gets the next point.

Parameters:

[in]

point

the positional value to set

Returns:

The next index value

int index

(

)

const [virtual]

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Returns a unique index for the current item in the iteration.

If the iteration is over the whole geometry then this index is the same as current point. If the iteration is over some elements of the geometry specified by a component then this index is the index in your geometry.

Returns:

The index of the current element

bool hasNormals

(

)

const [virtual]

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Indicates whether the underlying geometry has normals.

Returns:

• true this geometry has normals
• false this geometry has no normals

int indexUnsimplified

(

)

const [virtual]

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Returns a unique index for the current item in the iteration Rather than being the iterator index this is the index for the actual item when simplification is skipping items.

This index will be equal to index() if no simplification, otherwise it will be larger.

Returns:

The unsimplified index

int currentPoint

(

)

const

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Returns the index that is being iterated on.

This value is used when iterating over all elements of your geometry, i.e. when there are no components specified.

Returns:

The current point index

void setCurrentPoint

(

int

index

)

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Set the current index of the iteration.

This value is used when iterating over all elements of your geometry, i.e. when there are no components specified.

Parameters:

[in]

index

the current point in the iteration

int maxPoints

(

)

const

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Returns the largest index that will be iterated over.

This value is used when iterating over all elements of your geometry, i.e. when there are no components specified.

Returns:

The max index

void setMaxPoints

(

int

index

)

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Sets the largest index that will be iterated over.

This value is used when iterating over all elements of your geometry, i.e. when there are no components specified.

Parameters:

[in]

index

the maximum index value

void setObject

(

MPxSurfaceShape &

shape

)

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Optional method to set a shape object to iterate over to allow tweaking of the shape's history (input geometry).

Parameters:

[in]

shape

a user defined shape object

const char * className

(

)

[static]

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Returns the name of this class.

Returns:

The name of this class.