#include <MPxEmitterNode.h>

Class Description

Base class for user defined particle emitters.

MPxEmitterNode allows the creation and manipulation of dependency graph nodes representing particle emitters.

Examples:: ownerEmitter/ownerEmitter.h, simpleEmitter/simpleEmitter.h, and sweptEmitter/sweptEmitter.h.

Inheritance diagram for MPxEmitterNode:

Public Types
enum	MEmitterType { kDirectional = 0, kOmni, kSurface, kCurve, kVolume }
	Types of emitters. More...

Public Types inherited from MPxNode
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 }
	Defines the degree of parallelism of a node. More...

Public Member Functions
	MPxEmitterNode ()
	Class constructor.

virtual	~MPxEmitterNode ()
	The class destructor.

virtual MPxNode::Type	type () const
	This method returns the type of the node. More...

virtual MStatus	compute (const MPlug &plug, MDataBlock &dataBlock)
	This method should be overridden in user defined nodes. More...

virtual void	draw (M3dView &view, const MDagPath &path, M3dView::DisplayStyle style, M3dView::DisplayStatus)
	Overriding this method allows the drawing of custom geometry using standard OpenGL calls. More...

MEmitterType	getEmitterType (MDataBlock &block)
	Retrieves the type of the emitter, determined by the "emitterType" attribute value. More...

MObject	getOwnerShape ()
	If the emitter is a emitting from an object, this method returns the shape node for the object. More...

MTime	getCurrentTime (MDataBlock &block)
	Intended to be called from within the emitter's compute() method, this method returns the time at which the emitter is currently being evaluated. More...

MTime	getStartTime (int plugIndex, MDataBlock &block)
	Intended to be called from within the emitter's compute() method, this method returns the start times for each particle system or fluid into which the emitter is emitting. More...

MTime	getDeltaTime (int plugIndex, MDataBlock &block)
	Intended to be called from within the emitter's compute() method, this method returns the width of the time interval represented by the current emitter evaluation. More...

int	getRandomSeed (int plugIndex, MDataBlock &block)
	Intended to be called from within the emitter's compute() method, this method returns the random seed for a specified emission target (particle system or fluid shape into which the emitter is emitting). More...

void	getRandomState (int plugIndex, MDataBlock &block)
	Intended to be called from within the emitter's compute() method, this method copies the emitter node attribute representing the current random state for a particular emitter target into a local variable on the emitter object, to facilitate efficient random number generation using the randgen() method. More...

void	setRandomState (int plugIndex, MDataBlock &block)
	Intended to be called from within the emitter's compute() method, this method copies the emitter node class random state data member onto the emitter node's random state attribute. More...

void	resetRandomState (int plugIndex, MDataBlock &block)
	Intended to be called from within the emitter's compute() method, this method resets the emitter's random state data member. More...

double	randgen ()
	Intended to be called from within the emitter's compute() method, this method generates a double-precision random number in the rand [0,1]. More...

double	getRate (MDataBlock &block)
	Intended to be called from within the emitter's compute() method, this method retrieves the "rate" attribute value common to all particle and fluid emitters. More...

double	getMinDistance (MDataBlock &block)
	Intended to be called from within the emitter's compute() method, this method retrieves the "minDistance" attribute value common to all particle and fluid emitters. More...

double	getMaxDistance (MDataBlock &block)
	Intended to be called from within the emitter's compute() method, this method retrieves the "maxDistance" attribute value common to all particle and fluid emitters. More...

MPoint	getWorldPosition ()
	Returns the worldspace coordinates of the emitter. More...

MMatrix	getWorldMatrix ()
	Returns the matrix that maps from the emitter's local space coordinates to worldspace. More...

bool	volumePrimitiveBoundingBox (MBoundingBox &box)
	For volume emitters, this method returns the object-space bounding box of the volume primitive associated with the emitter. More...

bool	volumePrimitivePointInside (const MPoint &worldPoint, const MMatrix &emitterWorldMatrix)
	For volume emitters, this method determines whether a particular point in space lies within the volume defined by the emitter's volume primitive. More...

double	volumePrimitiveDistanceFromAxis (const MPoint &worldPoint, const MMatrix &emitterWorldMatrix)
	For volume emitters, this method determines the distance from a particular point to the major axis of the volumetric primitive associated with the emitter. More...

bool	hasValidEmission2dTexture (const MObject &texAttr, MStatus *status=NULL)
	Certain aspects of Maya's particle and fluid emitters can be textured using 2d textures. More...

MStatus	evalEmission2dTexture (const MObject &texAttr, MDoubleArray &uCoords, MDoubleArray &vCoords, MVectorArray resultColors, MDoubleArray resultAlphas)
	If a supported 2d texture (see hasValidEmission2dTexture() method documentation) is connected to the given emitter attribute, this method can be called to evaluate that texture at a number of (u,v) texture coordinate values. More...

Public Member Functions inherited from MPxNode
	MPxNode ()
	Constructor. More...

virtual	~MPxNode ()
	Destructor.

virtual void	postConstructor ()
	Post constructor. More...

virtual bool	getInternalValueInContext (const MPlug &plug, MDataHandle &dataHandle, MDGContext &ctx)
	This method is overridden by nodes that store attribute data in some internal format. More...

virtual bool	setInternalValueInContext (const MPlug &plug, const MDataHandle &dataHandle, MDGContext &ctx)
	This method is overridden by nodes that store attribute data in some internal format. More...

virtual bool	getInternalValue (const MPlug &plug, MDataHandle &dataHandle)
	This method is obsolete. More...

virtual bool	setInternalValue (const MPlug &plug, const MDataHandle &dataHandle)
	This method is obsolete. More...

virtual int	internalArrayCount (const MPlug &plug, const MDGContext &ctx) 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 &plug, const MPlug &otherPlug, 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 &plug, const MPlug &otherPlug, 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 MStatus	connectionMade (const MPlug &plug, const MPlug &otherPlug, bool asSrc)
	This method gets called when connections are made to attributes of this node. More...

virtual MStatus	connectionBroken (const MPlug &plug, const MPlug &otherPlug, bool asSrc)
	This method gets called when connections are broken with attributes of this node. More...

virtual MStatus	dependsOn (const MPlug &plug, const MPlug &otherPlug, bool &depends) const
	This method may be overridden by the user defined node. More...

virtual bool	isPassiveOutput (const MPlug &plug) 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 &plug, bool &isSaving)
	This method may be overridden by the user defined node. More...

virtual MPlug	passThroughToOne (const MPlug &plug) 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 &plug, MPlugArray &plugArray) 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 bool	isAbstractClass () const
	Override this class to return true if this node is an abstract node. 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 &table, const MObject &attr) const
	Adds content info to the specified table from a file path attribute. More...

bool	setExternalContentForFileAttr (const MObject &attr, const MExternalContentLocationTable &table)
	Sets content info in the specified attribute from the table. More...

virtual void	setExternalContent (const MExternalContentLocationTable &table)
	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...

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

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

Static Public Attributes
static MObject	mEmitterType
	emitter type attribute

static MObject	mRate
	rate attribute

static MObject	mSpeed
	speed attribute

static MObject	mDirection
	direction attribute

static MObject	mDirectionX
	X component of mDirection.

static MObject	mDirectionY
	Y component of mDirection.

static MObject	mDirectionZ
	Z component of mDirection.

static MObject	mOwnerPosData
	owner postion attribute, multi

static MObject	mOwnerVelData
	owner velocity attribute, multi

static MObject	mOwnerCentroid
	owner centroid attribute

static MObject	mOwnerCentroidX
	X component of mOwnerCentroid.

static MObject	mOwnerCentroidY
	Y component of mOwnerCentroid.

static MObject	mOwnerCentroidZ
	Z component of mOwnerCentroid.

static MObject	mSweptGeometry
	input swept geometry attribute

static MObject	mWorldMatrix
	world matrix attribute

static MObject	mStartTime
	start time attribute

static MObject	mDeltaTime
	delta time attribute

static MObject	mIsFull
	flag for maximum count attribute

static MObject	mInheritFactor
	inherit factor attribute

static MObject	mSeed
	random seed attribute

static MObject	mRandState
	random state attribute

static MObject	mCurrentTime
	current time attribute

static MObject	mOutput
	output particle attribute, multi

static MObject	mMinDistance
	min distance attribute

static MObject	mMaxDistance
	max distance attribute

Static Public Attributes inherited from MPxNode
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

Additional Inherited Members
Protected Member Functions inherited from MPxNode
virtual MDataBlock	forceCache (MDGContext &ctx=MDGContext::fsNormal)
	USE _forceCache() IN SCRIPT. More...

virtual void	setMPSafe (bool flag)
	USE _setMPSafe() 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...

Member Enumeration Documentation

enum MEmitterType

Types of emitters.

Enumerator
kDirectional
kOmni
kSurface
kCurve
kVolume

Member Function Documentation

MPxNode::Type type ( ) const

virtual

This method returns the type of the node.

It should not be overridden by the user. It will return MPxNode::kEmitterNode.

Returns: The type of node

Status Codes:

MS::kSuccess The undo was successful
MS::kFailure This method is not undoable

Reimplemented from MPxNode.

Reimplemented in MPxFluidEmitterNode.

MStatus compute	(	const MPlug &	plug,
		MDataBlock &	dataBlock
	)

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 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]	plug	plug representing the attribute that needs to be recomputed
[in]	dataBlock	data block containing storage for the node's attributes

Returns: Status code

Status Codes:

MS::kSuccess Compute was successful
MS::kFailure Compute failed

Reimplemented from MPxNode.

Reimplemented in MPxFluidEmitterNode.

Examples:: ownerEmitter/ownerEmitter.h, simpleEmitter/simpleEmitter.h, and sweptEmitter/sweptEmitter.h.

void draw	(	M3dView &	view,
		const MDagPath &	path,
		M3dView::DisplayStyle	style,
		M3dView::DisplayStatus
	)

virtual

Overriding this method allows the drawing of custom geometry using standard OpenGL calls.

The OpenGL state should be left in the same state that it was in previously. The OpenGL routine glPushAttrib may be used to make this easier.

When this routine is called, the following conditions may be assumed:

the correct transform matrix will be loaded for the node, so the geometry should be drawn in local space
the correct default color will be set for wire frame drawing given the object's state (eg active, dormant, etc.)
the object is not invisible or hidden
if the object has a bounding box, then the bounding box is at least partially in the frustum

As a convenience, this draw method will also be used by OpenGL's selection mechanism to determine whether this object gets selected by a particular mouse event. The user does not need to write a separate selection routine.

Parameters

[in]	view	3D view that is being drawn into
[in]	path	to this node in the DAG
[in]	style	style to draw object in

Examples:: simpleEmitter/simpleEmitter.h.

MPxEmitterNode::MEmitterType getEmitterType ( MDataBlock & block )

Retrieves the type of the emitter, determined by the "emitterType" attribute value.

This is intended to be called from within the emitter's compute() method, in order to decide how the emitter should behave when evaluated.

Parameters

[in] block data block containing storage for the node's attributes

Returns: An MEmitterType value representing the type of emitter (directional, omni, surface, curve, or volume)

MObject getOwnerShape ( )

If the emitter is a emitting from an object, this method returns the shape node for the object.

Returns: An MObject representing the "owner" of this emitter (ie the object being emitted from, or kNullObj if the emitter is not emitting from an object.

MTime getCurrentTime ( MDataBlock & block )

Intended to be called from within the emitter's compute() method, this method returns the time at which the emitter is currently being evaluated.

This is equivalent to querying the "currentTime" attribute on the emitter.

Parameters

[in] block data block containing storage for the node's attributes

Returns: The time at which the emitter is being evaluated.

MTime getStartTime	(	int	plugIndex,
		MDataBlock &	block
	)

Intended to be called from within the emitter's compute() method, this method returns the start times for each particle system or fluid into which the emitter is emitting.

Each of these "targets" is identified by an index value corresponding to the order in which they are connected to the emitter. The start time value gives the time at which the given target is to start receiving particles or fluid. If the current time is less than the start time for a target, then nothing should be emitted into that target in the current evaluation. This value is taken by evaluating an element of the emitter node's "startTime" array attribute.

Parameters

[in]	plugIndex	identifies which emitter target's start time is to be evaluated.
[in]	block	data block containing storage for the node's attributes

Returns: The start time for the specified target, ie the time at which the emitter is to start emitting into that target.

MTime getDeltaTime	(	int	plugIndex,
		MDataBlock &	block
	)

Intended to be called from within the emitter's compute() method, this method returns the width of the time interval represented by the current emitter evaluation.

Usually emitter emission rates are given as rates per second, so by converting this deltaTime value to seconds, plugin emitters can determine how many particles or how much fluid to emit in the current evaluation. This value is taken from the emitter's "deltaTime" attribute value, and can vary between different emitter targets (particle systems or fluid shapes into which the emitter is emitting), due to potential differences in oversampling settings. The "plugIndex" parameter indicates which target's time delta is being evaluated.

Parameters

[in]	plugIndex	identifies which emitter target's time delta is to be evaluated.
[in]	block	data block containing storage for the node's attributes

Returns: The time delta for the current emitter evaluation on the specified target.

int getRandomSeed	(	int	plugIndex,
		MDataBlock &	block
	)

Intended to be called from within the emitter's compute() method, this method returns the random seed for a specified emission target (particle system or fluid shape into which the emitter is emitting).

This seed value is set on the target itself, and should be used to ensure that any randomized emission behavior is repeatable when animations are played back repeatedly. The resetRandomState() method uses this value (see its documentation for details on how to implement repeatable randomized behaviour in emitters). This value is obtained by evaluating an element of the emitter's "seed" array attribute.

Parameters

[in]	plugIndex	identifies which emitter target's random seed is to be evaluated.
[in]	block	data block containing storage for the node's attributes

Returns: The random seed value for the specified target.

void getRandomState	(	int	plugIndex,
		MDataBlock &	block
	)

Intended to be called from within the emitter's compute() method, this method copies the emitter node attribute representing the current random state for a particular emitter target into a local variable on the emitter object, to facilitate efficient random number generation using the randgen() method.

See the documentation for resetRandomState() for a description of how to use this method in conjunction with the other random stream methods of this class.

There is only one local random state data member, so care should be taken not to inadvertently overwrite this member by calling getRandomState() on one target before setRandomState() has been called on a previously-evaluated target.

Parameters

[in]	plugIndex	identifies which emitter target's random state is to be copied to the local random state data member.
[in]	block	data block containing storage for the node's attributes

void setRandomState	(	int	plugIndex,
		MDataBlock &	block
	)

Intended to be called from within the emitter's compute() method, this method copies the emitter node class random state data member onto the emitter node's random state attribute.

See the documentation for resetRandomState() for a description of how to use this method in conjunction with the other random stream methods of this class.

There is only one local random state data member, so care should be taken not to inadvertently write the wrong random state value to the attribute by calling setRandomState() on a target before getRandomState() has been called for that target.

Parameters

[in]	plugIndex	identifies which emitter target's random state is to be written from the local random state data member.
[in]	block	data block containing storage for the node's attributes

void resetRandomState	(	int	plugIndex,
		MDataBlock &	block
	)

Intended to be called from within the emitter's compute() method, this method resets the emitter's random state data member.

To implement repeatable randomized emitter behavior, the following steps should be followed:

When the current time is less than the start time, call resetRandomState(). This sets the emitter's random state to an initial value determined by the random seed for the given target. This initializes both the emitter's randomState attribute and a random state data member on the emitter class.
When the emitter needs to emit either particles or fluid in a compute() call, first call the getRandomState() method. This copies the emitter's current random state from its randomState attribute into the data member on the emitter class.
Over the course of the compute() method, when a random value is required, call randgen(). This generates a random value using the random state data member value, which is then incremented.
When the emitter is finished emitting, call the setRandomState() method to set the random state data member's value back onto the random state attribute for the node. This way, the next evaluation of the emitter will pick up where the previous one left off in the random sequence.

This way, the emitter gets a repeatable stream of random numbers that is independent of the order of evaluation of the various emitter targets. Persistence is achieved by storing the random state on emitter attributes between evaluations, and efficiency is achieved by using a local random state variable during evaluations.

Parameters

[in]	plugIndex	identifies which emitter target's random state is to be reset.
[in]	block	data block containing storage for the node's attributes

double randgen ( )

Intended to be called from within the emitter's compute() method, this method generates a double-precision random number in the rand [0,1].

The emitter object's random state data member is used to generate the random number, and will be updated after the number is generated. To generate a stream of random numbers for a particular target, ensure that getRandomState() is called before calling randgen(), and that setRandomState() is called after all the random numbers have been generated. See the documentation for resetRandomState() for a description of how to use this method in conjunction with the other random stream methods of this class.

Returns: A double-precision random number between 0 and 1.

double getRate ( MDataBlock & block )

Intended to be called from within the emitter's compute() method, this method retrieves the "rate" attribute value common to all particle and fluid emitters.

For particle emitters, this indicates the number of particles to be emitted per second. For fluid emitters, this value is usually used as a multiplier applied to the emission rates for various fluid grids such as density, temperature, etc.

Parameters

[in] block data block containing storage for the node's attributes

Returns: The emission rate for the emitter.

double getMinDistance ( MDataBlock & block )

Intended to be called from within the emitter's compute() method, this method retrieves the "minDistance" attribute value common to all particle and fluid emitters.

This value indicates the minimum distance from the emitter center at which fluid or particles will be emitted.

Parameters

[in] block data block containing storage for the node's attributes

Returns: The minimum emission distance for the emitter.

double getMaxDistance ( MDataBlock & block )

Intended to be called from within the emitter's compute() method, this method retrieves the "maxDistance" attribute value common to all particle and fluid emitters.

This value indicates the maximum distance from the emitter center at which fluid or particles will be emitted.

Parameters

[in] block data block containing storage for the node's attributes

Returns: The maximum emission distance for the emitter.

MPoint getWorldPosition ( )

Returns the worldspace coordinates of the emitter.

For curve, surface, and volume emitters, this returns the worldspace coordinates of the center of the emitter's local space. For point emitters, this value usually corresponds to the position of the emitter object itself.

Returns: The worldspace coordinates of the center of the emitter's local space.

Examples:: ownerEmitter/ownerEmitter.h, and simpleEmitter/simpleEmitter.h.

MMatrix getWorldMatrix ( )

Returns the matrix that maps from the emitter's local space coordinates to worldspace.

Returns: Emitter's object to world space transformation matrix.

bool volumePrimitiveBoundingBox ( MBoundingBox & box )

For volume emitters, this method returns the object-space bounding box of the volume primitive associated with the emitter.

Parameters

[out] box receives the object space bounding box for the emission volume primitive.

Returns: true if the emitter has an associated volume primitive, false otherwise.

bool volumePrimitivePointInside	(	const MPoint &	worldPoint,
		const MMatrix &	emitterWorldMatrix
	)

For volume emitters, this method determines whether a particular point in space lies within the volume defined by the emitter's volume primitive.

Parameters

[in]	worldPoint	worldspace coordinates of the point to be tested.
[in]	emitterWorldMatrix	object to worldspace matrix for the emitter, which can be obtained using the MPxEmitterNode::getWorldMatrix() method.

Returns: true if the point lies inside the emitter's volume primitive, false otherwise.

double volumePrimitiveDistanceFromAxis	(	const MPoint &	worldPoint,
		const MMatrix &	emitterWorldMatrix
	)

For volume emitters, this method determines the distance from a particular point to the major axis of the volumetric primitive associated with the emitter.

For fluid emitters, this distance can be used to implement simple emission dropoff behavior.

Parameters

[in]	worldPoint	worldspace coordinates of the point to be tested.
[in]	emitterWorldMatrix	object to worldspace matrix for the emitter, which can be obtained using the MPxEmitterNode::getWorldMatrix() method.

Returns: The distance from the point to the major axis of the emitter's volume primitive.

bool hasValidEmission2dTexture	(	const MObject &	texAttr,
		MStatus *	status = `NULL`
	)

Certain aspects of Maya's particle and fluid emitters can be textured using 2d textures.

For example, surface particle emitters can use a 2d texture to modulate the emission rate over the surface. For these purposes, only a subset of Maya's textures are supported, namely the default 2d textures (bulge, checker, cloth, file, fluid texture 2d, fractal, grid, mountain, movie, noise, ocean, ramp, water). No other nodes are supported. This method takes an attribute on an emitter, and determines if there is a supported texture connected to it. If the texture is supported, then the evalEmission2dTexture() method can be called to evaluate the texture at various (u,v) coordinate values.

Parameters

[in]	texAttr	attribute to be tested for a valid texture connection.
[out]	status	status code.

Status Codes:

MS::kSuccess The connected texture was successfully examined.
MS::kUnknownParameter There was no node connected to the specified attribute.

Returns: true if the node connected to the specified emitter attribute is a texture that can be evaluated using the evalEmission2dTexture() method, false otherwise.

MStatus evalEmission2dTexture	(	const MObject &	texAttr,
		MDoubleArray &	uCoords,
		MDoubleArray &	vCoords,
		MVectorArray *	resultColors,
		MDoubleArray *	resultAlphas
	)

If a supported 2d texture (see hasValidEmission2dTexture() method documentation) is connected to the given emitter attribute, this method can be called to evaluate that texture at a number of (u,v) texture coordinate values.

Parameters

[in]	texAttr	attribute whose connected texture is to be evaluated.
[in]	uCoords	array of u coordinate values
[in]	vCoords	array of v coordinate values
[out]	resultColors	if non-NULL, receives the result of the connected texture's outColor attribute, evaluated at all the (u,v) coordinates given by the uCoords and vCoords arrays.
[out]	resultAlphas	if non-NULL, receives the outAlpha values evaluated from the texture at these same points.

Status Codes:

MS::kSuccess The connected texture was successfully evaluated
MS::kUnknownParameter There was no texture, or an unsupported texture connected to the specified attribute, so textured values could not be evaluated.

const char * className ( )

static

Returns the name of this class.

Returns: The name of this class.

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

MPxEmitterNode.h
MPxEmitterNode.cpp

MPxEmitterNode Class Reference

Class Description

Public Types

Public Member Functions

Static Public Member Functions

Static Public Attributes

Additional Inherited Members

Member Enumeration Documentation

Member Function Documentation