javax.media.j3d
Class PositionInterpolator

java.lang.Object
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  +--javax.media.j3d.SceneGraphObject
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        +--javax.media.j3d.Node
              |
              +--javax.media.j3d.Leaf
                    |
                    +--javax.media.j3d.Behavior
                          |
                          +--javax.media.j3d.Interpolator
                                |
                                +--javax.media.j3d.PositionInterpolator

public class PositionInterpolator

extends Interpolator

Position interpolator behavior. This class defines a behavior that modifies the translational component of its target TransformGroup by linearly interpolating between a pair of specified positions (using the value generated by the specified Alpha object). The interpolated position is used to generate a translation transform along the local X-axis of this interpolator.

Fields inherited from class javax.media.j3d.Interpolator

defaultWakeupCriterion

Fields inherited from class javax.media.j3d.Node

ALLOW_AUTO_COMPUTE_BOUNDS_READ, ALLOW_AUTO_COMPUTE_BOUNDS_WRITE, ALLOW_BOUNDS_READ, ALLOW_BOUNDS_WRITE, ALLOW_COLLIDABLE_READ, ALLOW_COLLIDABLE_WRITE, ALLOW_LOCAL_TO_VWORLD_READ, ALLOW_PICKABLE_READ, ALLOW_PICKABLE_WRITE, ENABLE_COLLISION_REPORTING, ENABLE_PICK_REPORTING

Constructor Summary

PositionInterpolator(Alpha alpha, TransformGroup target)
Constructs a trivial position interpolator with a specified target, an axisOfTranslation set to Identity, a startPosition of 0.0f, and an endPosition of 1.0f.

PositionInterpolator(Alpha alpha, TransformGroup target, Transform3D axisOfTranslation, float startPosition, float endPosition)
Constructs a new position interpolator that varies the target TransformGroup's translational component (startPosition and endPosition).

Method Summary

Node	cloneNode(boolean forceDuplicate) Used to create a new instance of the node.
Transform3D	getAxisOfTranslation() This method retrieves this interpolator's axis of translation.
float	getEndPosition() This method retrieves this interpolator's endPosition.
float	getStartPosition() This method retrieves this interpolator's startPosition.
TransformGroup	getTarget() This method retrieves this interpolator's target TransformGroup reference.
void	processStimulus(java.util.Enumeration criteria) This method is invoked by the behavior scheduler every frame.
void	setAxisOfTranslation(Transform3D axisOfTranslation) This method sets the axis of translation for this interpolator.
void	setEndPosition(float position) This method sets the endPosition for this interpolator.
void	setStartPosition(float position) This method sets the startPosition for this interpolator.
void	setTarget(TransformGroup target) This method sets the target for this interpolator.
void	updateNodeReferences(NodeReferenceTable referenceTable) Callback used to allow a node to check if any scene graph objects referenced by that node have been duplicated via a call to cloneTree.

Methods inherited from class javax.media.j3d.Interpolator

getAlpha, initialize, setAlpha

Methods inherited from class javax.media.j3d.Behavior

getEnable, getSchedulingBoundingLeaf, getSchedulingBounds, getView, postId, setEnable, setSchedulingBoundingLeaf, setSchedulingBounds, wakeupOn

Methods inherited from class javax.media.j3d.Node

cloneTree, cloneTree, cloneTree, cloneTree, cloneTree, cloneTree, duplicateNode, getBounds, getBoundsAutoCompute, getCollidable, getLocalToVworld, getLocalToVworld, getParent, getPickable, setBounds, setBoundsAutoCompute, setCollidable, setPickable

Methods inherited from class javax.media.j3d.SceneGraphObject

clearCapability, duplicateSceneGraphObject, getCapability, getUserData, isCompiled, isLive, setCapability, setUserData

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PositionInterpolator

public PositionInterpolator(Alpha alpha,
                            TransformGroup target)

Constructs a trivial position interpolator with a specified target, an axisOfTranslation set to Identity, a startPosition of 0.0f, and an endPosition of 1.0f.

Parameters:

alpha - The alpha object for this Interpolator

target - The target for this position Interpolator

PositionInterpolator

public PositionInterpolator(Alpha alpha,
                            TransformGroup target,
                            Transform3D axisOfTranslation,
                            float startPosition,
                            float endPosition)

Constructs a new position interpolator that varies the target TransformGroup's translational component (startPosition and endPosition).

Parameters:

alpha - the alpha object for this interpolator

target - the transform node effected by this positionInterpolator

axisOfTranslation - the transform that defines the local coordinate system in which this interpolator operates. The translation is done along the X-axis of this local coordinate system.

startPosition - the starting position

endPosition - the ending position

Method Detail

setStartPosition

public void setStartPosition(float position)

This method sets the startPosition for this interpolator.

Parameters:

position - The new start position

getStartPosition

public float getStartPosition()

This method retrieves this interpolator's startPosition.

Returns:

the interpolator's start position value

setEndPosition

public void setEndPosition(float position)

This method sets the endPosition for this interpolator.

Parameters:

position - The new end position

getEndPosition

public float getEndPosition()

This method retrieves this interpolator's endPosition.

Returns:

the interpolator's end position vslue

setTarget

public void setTarget(TransformGroup target)

This method sets the target for this interpolator.

Parameters:

target - The target TransformGroup

getTarget

public TransformGroup getTarget()

This method retrieves this interpolator's target TransformGroup reference.

Returns:

the Interpolator's target TransformGroup

setAxisOfTranslation

public void setAxisOfTranslation(Transform3D axisOfTranslation)

This method sets the axis of translation for this interpolator.

Parameters:

axisOfTranslation - the transform that defines the local coordinate system in which this interpolator operates

getAxisOfTranslation

public Transform3D getAxisOfTranslation()

This method retrieves this interpolator's axis of translation.

Returns:

the interpolator's axis of translation

processStimulus

public void processStimulus(java.util.Enumeration criteria)

This method is invoked by the behavior scheduler every frame. It maps the alpha value that corresponds to the current time into a translation value, computes a transform based on this value, and updates the specified TransformGroup node with this new transform.

Overrides:

processStimulus in class Behavior

Parameters:

criteria - an enumeration of the criteria that caused the stimulus

cloneNode

public Node cloneNode(boolean forceDuplicate)

Used to create a new instance of the node. This routine is called by cloneTree to duplicate the current node.

Overrides:

cloneNode in class Node

Parameters:

forceDuplicate - when set to true, causes the duplicateOnCloneTree flag to be ignored. When false, the value of each node's duplicateOnCloneTree variable determines whether NodeComponent data is duplicated or copied.

See Also:

Node.cloneTree(), Node.cloneNode(boolean), Node.duplicateNode(javax.media.j3d.Node, boolean), NodeComponent.setDuplicateOnCloneTree(boolean)

updateNodeReferences

public void updateNodeReferences(NodeReferenceTable referenceTable)

Callback used to allow a node to check if any scene graph objects referenced by that node have been duplicated via a call to cloneTree. This method is called by cloneTree after all nodes in the sub-graph have been duplicated. The cloned Leaf node's method will be called and the Leaf node can then look up any object references by using the getNewObjectReference method found in the NodeReferenceTable object. If a match is found, a reference to the corresponding object in the newly cloned sub-graph is returned. If no corresponding reference is found, either a DanglingReferenceException is thrown or a reference to the original object is returned depending on the value of the allowDanglingReferences parameter passed in the cloneTree call.

NOTE: Applications should not call this method directly. It should only be called by the cloneTree method.

Overrides:

updateNodeReferences in class Behavior

Parameters:

referenceTable - a NodeReferenceTableObject that contains the getNewObjectReference method needed to search for new object instances.

See Also:

NodeReferenceTable, Node.cloneTree(), DanglingReferenceException