MPxFieldNode Class Reference
[OpenMayaFX - API module for effects, Proxy classes]

#include <MPxFieldNode.h>

Inheritance diagram for MPxFieldNode:

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Collaboration diagram for MPxFieldNode:

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List of all members.

Detailed Description

Base class for user defined fields.

MPxFieldNode allows the creation and manipulation of dependency graph nodes representing fields. This is the top level of a hierarchy of field node function sets. It permits manipulation of the attributes common to all types of fields.

Examples:

: dynExprField.h, and torusField.h.


Public Member Functions
	MPxFieldNode ()
virtual	~MPxFieldNode ()
virtual MPxNode::Type	type () const
virtual MStatus	compute (const MPlug &plug, MDataBlock &dataBlock)
virtual MStatus	getForceAtPoint (const MVectorArray &point, const MVectorArray &velocity, const MDoubleArray &mass, MVectorArray &force, double deltaTime)
virtual MStatus	iconSizeAndOrigin (GLuint &width, GLuint &height, GLuint &xbo, GLuint &ybo)
virtual MStatus	iconBitmap (GLubyte *bitmap)
virtual void	draw (M3dView &view, const MDagPath &path, M3dView::DisplayStyle style, M3dView::DisplayStatus)
virtual double	falloffCurve (const double param, MStatus *ReturnStatus=NULL)
virtual bool	isFalloffCurveConstantOne (MStatus *ReturnStatus=NULL)
Static Public Attributes
static MObject	mMagnitude
	magnitude attribute
static MObject	mAttenuation
	attenuation attribute
static MObject	mMaxDistance
	maximum distance attribute
static MObject	mUseMaxDistance
	flag for maximum distance attribute
static MObject	mApplyPerVertex
	flag for per vertex attribute
static MObject	mInputData
	input attribute compound, multi
static MObject	mInputPositions
	child attribute, multi
static MObject	mInputVelocities
	child attribute, multi
static MObject	mInputMass
	child attribute, multi
static MObject	mDeltaTime
	child attribute
static MObject	mInputForce
	forces input attribute, multi
static MObject	mOutputForce
	forces output attribute, multi
static MObject	mOwnerCentroidX
	X component of mOwnerCentroid.
static MObject	mOwnerCentroidY
	Y component of mOwnerCentroid.
static MObject	mOwnerCentroidZ
	Z component of mOwnerCentroid.
static MObject	mOwnerCentroid
	owner centroid attribute
static MObject	mOwnerPosData
	owner position attribute, multi
static MObject	mOwnerVelData
	owner velocity attribute, multi
static MObject	mWorldMatrix
	world matrix attribute
static MObject	mInputPPData
	Attribute for input pp data from particleShape.
static MObject	mOwnerPPData
	Attribute for input pp data from owner particleShape.

Constructor & Destructor Documentation

MPxFieldNode::MPxFieldNode ( )

Class constructor.

MPxFieldNode::~MPxFieldNode ( ) [virtual]

The class destructor.

Member Function Documentation

MPxNode::Type MPxFieldNode::type ( ) const [virtual]

This method returns the type of the node. This method should not be overridden by the user. It will return MPxNode::kFieldNode.

Returns:: The type of node

Status Codes:

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

Reimplemented from MPxNode.

MStatus MPxFieldNode::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.

Examples:

: dynExprField.h, and torusField.h.

MStatus MPxFieldNode::getForceAtPoint	(	const MVectorArray &	point,
		const MVectorArray &	velocity,
		const MDoubleArray &	mass,
		MVectorArray &	force,
		double	deltaTime
	)			`[virtual]`

This method is not required to be overridden, it is only necessary for compatibility with the MFnField function set.

Compute the force of a field on an array of points, given their position, velocity, and mass.

This method uses MVectorArray to represent the positions of a point.

Parameters:

`[in]`	point	array of positions for each point.
`[in]`	velocity	array of velocities for each point. If the length of the velocity array is 0, a velocity of 0.0 is assumed for all the points. Note the velocity array is a requirement for the Air and Drag fields to compute forces.
`[in]`	mass	array of mass values for each point. If the length of the mass array is 0, a mass of 1.0 is assumed for all the points.
`[out]`	force	output array of forces applied to each point. If the length of the force array supplied is 0, the array is automatically resized. If the contents of the force array contains data, the computed force is added to the supplied data. This can be useful to accumulate forces of multiple fields.
`[in]`	deltaTime	time increment in seconds

Returns:: Status code

Status Codes:

MS::kSuccess The method was successful.
MS::kFailure An object error has occurred.

Examples:

: torusField.h.

MStatus MPxFieldNode::iconSizeAndOrigin	(	GLuint &	width,
		GLuint &	height,
		GLuint &	xbo,
		GLuint &	ybo
	)			`[virtual]`

This method is not required to be overridden. The arguments have the same meaning as defined in OpenGL's glBitmap method.

Define the size and the origin for the icon.

Parameters:

`[in]`	width	the width of the icon in pixels. It needs to be a multiple of 32 on windows and a multiple of 16 on any other platform.
`[in]`	height	the height of the icon in pixels. It needs to be a multiple of 32 on windows and a multiple of 16 on any other platform.
`[in]`	xbo	the origin of the icon in x direction.
`[in]`	ybo	the origin of the icon in y direction.

Returns:: Status code

Status Codes:

MS::kSuccess has custom icon.
MS::kFailure no custom icon.

Examples:

: dynExprField.h, and torusField.h.

MStatus MPxFieldNode::iconBitmap ( GLubyte * bitmap ) [virtual]

This method is not required to be overridden. The arguments have the same meaning as defined in OpenGL's glBitmap method.

Define the bitmap for the icon. The memory in bitmap has been allocated according to the width and height in iconSizeAndOrigin().

Parameters:

[in] bitmap bits used to define the bitmap.

Returns:: Status code

Status Codes:

MS::kSuccess has custom icon.
MS::kFailure no custom icon.

Examples:

: dynExprField.h, and torusField.h.

void MPxFieldNode::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:

: torusField.h.

double MPxFieldNode::falloffCurve	(	const double	param,
		MStatus *	ReturnStatus = `NULL`
	)			`[virtual]`

Returns the falloff at the given parameter value.

Parameters:

`[in]`	param	Parameter value in the range [0.0, 1.0]
`[out]`	ReturnStatus	Status code

Returns:: The falloff value at the given the param.

Status Codes:

MS::kSuccess The method was successful.
MS::kFailure An object error has occurred.

bool MPxFieldNode::isFalloffCurveConstantOne ( MStatus * ReturnStatus = NULL ) [virtual]

Returns true if the falloffCurve is a constant one (default) or false if not.

Parameters:

[out] ReturnStatus Status code

Returns:: true if the falloff curve is a constant one, false otherwise

Status Codes:

MS::kSuccess The method was successful.
MS::kFailure An object error has occurred.

MPxFieldNode Class Reference [OpenMayaFX - API module for effects, Proxy classes]

Detailed Description

Public Member Functions

Static Public Attributes

Constructor & Destructor Documentation

Member Function Documentation

MPxFieldNode Class Reference
[OpenMayaFX - API module for effects, Proxy classes]