XdkWrl: CoordinateDeformer Class Reference

6.14 CoordinateDeformer

CoordinateDeformer allows a free form deformation on a set of MFVec3f Coordinate nodes by using a NURBS volume. Conceptually, a set of input Coordinate nodes is placed into a non-uniform grid volume. If the grid control points are animated or deformed the output Coordinate nodes are updated accordingly.

The input to the deformer is a list of Coordinate nodes, where each Coordinate node defines a 3D parameter (u,v,w) for evaluation. The corresponding Cartesian output value is computed from the NURBS control grid. The children node contains a scene graph that typically consists of IndexedFaceSet nodes referring to a deformed Coordinate node in outputCoords.

The uDimension, vDimension, wDimension, controlPoint, weight, uKnot, vKnot, wKnot, uOrder, vOrder, and wOrder fields define the NURBS in three dimensions. The definition is similar to the NurbsSurface node.

The inputCoord field, if specified, shall contain a set of Coordinate nodes.

The outputCoord field, shall contain a set of Coordinate nodes. The number of nodes shall be equal to the number of nodes in inputCoord. The nodes themselves should be distinct from nodes in inputCoords.

The inputTransform field, if specified, shall contain a set of Transform nodes, the number of nodes shall be equal to the number of nodes in inputCoord.

By animating the controlPoint field, IndexedFaceSet nodes using a Coordinate node from outputCoords are deformed over time. Similarly, the point field in an input Coordinate node can be animated. By changing a Transform node in the inputTransform parameter, geometry can be moved through the deformation space (space warp).

CoordinateDeformer is a group node and shall be part of the transform hierarchy if evaluation is required. Points in the Coordinate node contained in outputCoord are recomputed and updated whenever the points of the inputCoord Coordinate are changed, any exposedField of the CoordinateDeformer itself is changed, or if any of the supplied inputTransform nodes are changed. Implementations may defer or even skip evaluation until the CoordinateDeformer node is displayed; i.e., if the node is not currently part of the traversed scene graph, or the node is not being rendered because the bounding box of the node (or the bounding box computed from the controlPoint list) falls outside the view frustum.

In some respects, CoordinateDeformer is a special version of a CoordinateInterpolator. The CoordinateDeformer is a group node in order to make the animation locatable in the scene graph at a certain 3D position. Normally, VRML interpolators do not define a bounding box and so are not culled from the scene. This behaviour may be achieved explicitly by routing the output of a VisibilitySensor to the controlling TimeSensor node.

Example:
DEF FFD CoordinateDeformer {
  controlPoint [ ... ]
  inputCoord DEF inputCoord Coordinate { point [ ... ] }
  outputCoord DEF outputCoord Coordinate { point [ ... ] }
  children Shape {
    geometry IndexedFaceSet {
      coord USE outputCoord 
        coordIndex [ ... ] }
    }
  }

The following is additional code to animate the FFD node:

DEF Timer TimeSensor {}
DEF FFDGridInterpolator CoordinateInterpolator { ... }
ROUTE FFDGridInterpolator.value_changed TO FFD.set_controlPoint
ROUTE Timer.fraction_changed TO FFDGridInterpolator.set_fraction

If a given input coordinate value (optionally transformed by the corresponding Transform node) exceeds the parametric range of one of the knot vectors, the corresponding output coordinate value will be left unchanged. This is useful to deform only a subset of the coordinates or to animate different parts of the coordinate node using different CoordinateDeformer nodes.

Constructor & Destructor Documentation

Member Function Documentation

wrl::Node * duplicate ( std::map< const Node *, Node * > & ) const [virtual]

Implements Node.

wrl::Node * duplicate ( ) const [virtual]

Returns a deep copy of this node, that is a fully independant node with all children (if any) also copied. This is mainly useful for instanciating protos.

Implements Node.

wrl::Node::EventInHandle eventIn ( const unsigned int n ) [virtual]

Return a handle on the i th event in of the node or a "unknown" typed handle if there is no such node. Here is how i is related to fields:

0 : addChildren
1 : removeChildren
2 : set_children
3 : set_controlPoint
4 : set_inputCoord
5 : set_inputTransform
6 : set_outputCoord
7 : set_weight

This function is useful, with nbEventsIn() if you want to traverse all events in of a Node.

Implements Node.

wrl::Node::EventInHandle eventIn ( const std::string & n ) [virtual]

Return a handle on the event in named n of the node or a "unknown" typed handle if there is no such event. Valid names are:

addChildren
removeChildren
set_children
set_controlPoint
set_inputCoord
set_inputTransform
set_outputCoord
set_weight

Implements Node.

wrl::Node::EventOutHandle eventOut ( const unsigned int n ) [virtual]

Return a handle on the i th event out of the node or a "unknown" typed handle if there is no such node. Here is how i is related to fields:

0 : children_changed
1 : controlPoint_changed
2 : inputCoord_changed
3 : inputTransform_changed
4 : outputCoord_changed
5 : weight_changed This function is useful, with nbEventsOut() if you want to traverse all events in of a Node.

Implements Node.

wrl::Node::EventOutHandle eventOut ( const std::string & n ) [virtual]

Return a handle on the event out named n of the node or a "unknown" typed handle if there is no such event. Valid names are:

children_changed
controlPoint_changed
inputCoord_changed
inputTransform_changed
outputCoord_changed
weight_changed

Implements Node.

wrl::Node::FieldHandle field ( const unsigned int n ) [virtual]

Return a handle on the i th field of the node or a "unknown" typed handle if there is no such node. Here is how i is related to fields:

0 : children
1 : controlPoint
2 : inputCoord
3 : inputTransform
4 : outputCoord
5 : weight
6 : bboxCenter
7 : bboxSize
8 : uDimension
9 : uKnot
10 : uOrder
11 : vDimension
12 : vKnot
13 : vOrder
14 : wDimension
15 : wKnot
16 : wOrder This function is useful, with nbFields() if you want to traverse all fields of a Node.

Implements Node.

wrl::Node::FieldHandle field ( const std::string & n ) [virtual]

Return a handle on the field named n of the node or a "unknown" typed handle if there is no such field. Valid names are:

children
controlPoint
inputCoord
inputTransform
outputCoord
weight
bboxCenter
bboxSize
uDimension
uKnot
uOrder
vDimension
vKnot
vOrder
wDimension
wKnot
wOrder

Implements Node.

bool isSetToDefaultValue ( const unsigned int i ) const [virtual]

Implements Node.

unsigned int nbEventsIn ( ) const [inline, virtual]

Returns the number of events in for this node type.

Implements Node.

unsigned int nbEventsOut ( ) const [inline, virtual]

Returns the number of events out for this node type.

Implements Node.

unsigned int nbFields ( ) const [inline, virtual]

Returns the number of fields (exposed or not) for this node type.

Implements Node.

const char * typeName ( ) const [inline, virtual]

Returns "CoordinateDeformer". Useful for printing.

Implements Node.


Public Member Functions
	CoordinateDeformer (const char *name="")
virtual	~CoordinateDeformer ()
virtual unsigned int	nbFields () const
virtual FieldHandle	field (const std::string &n)
virtual FieldHandle	field (const unsigned int i)
virtual bool	isSetToDefaultValue (const unsigned int i) const
virtual unsigned int	nbEventsIn () const
virtual EventInHandle	eventIn (const std::string &n)
virtual EventInHandle	eventIn (const unsigned int i)
virtual unsigned int	nbEventsOut () const
virtual EventOutHandle	eventOut (const std::string &n)
virtual EventOutHandle	eventOut (const unsigned int i)
const char *	typeName () const
virtual Node *	duplicate () const
virtual Node *	duplicate (std::map< const Node , Node > &) const
Public Attributes
Exposed Fields
A field that is capable of receiving events via an eventIn to change its value(s), and generating events via an eventOut when its value(s) change.
MFNode	children
MFVec3f	controlPoint
MFNode	inputCoord
MFNode	inputTransform
MFNode	outputCoord
MFFloat	weight
Fields
A property or attribute of a node. Each node type has a fixed set of fields. Fields may contain various kinds of data and one or many values. Each field has a default value.
SFVec3f	bboxCenter
SFVec3f	bboxSize
SFInt32	uDimension
MFFloat	uKnot
SFInt32	uOrder
SFInt32	vDimension
MFFloat	vKnot
SFInt32	vOrder
SFInt32	wDimension
MFFloat	wKnot
SFInt32	wOrder
Events In
EventIn< MFNode >	addChildren
EventIn< MFNode >	removeChildren
EventIn< MFNode >	set_children
EventIn< MFVec3f >	set_controlPoint
EventIn< MFNode >	set_inputCoord
EventIn< MFNode >	set_inputTransform
EventIn< MFNode >	set_outputCoord
EventIn< MFFloat >	set_weight
Events Out
EventOut< MFNode >	children_changed
EventOut< MFVec3f >	controlPoint_changed
EventOut< MFNode >	inputCoord_changed
EventOut< MFNode >	inputTransform_changed
EventOut< MFNode >	outputCoord_changed
EventOut< MFFloat >	weight_changed

CoordinateDeformer Class Reference
[Standard Node Types]

Public Member Functions

Public Attributes

Detailed Description

6.14 CoordinateDeformer

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation

CoordinateDeformer Class Reference [Standard Node Types]

Public Member Functions

Public Attributes

Detailed Description

6.14 CoordinateDeformer

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation

CoordinateDeformer Class Reference
[Standard Node Types]