com.jme3.bullet.joints

Class PhysicsJoint

java.lang.Object

com.jme3.bullet.joints.PhysicsJoint

All Implemented Interfaces:

Savable

Direct Known Subclasses:

ConeJoint, HingeJoint, Point2PointJoint, SixDofJoint, SliderJoint

public abstract class PhysicsJoint
extends java.lang.Object
implements Savable

The abstract base class for physics joints based on Bullet's btTypedConstraint, used to connect 2 dynamic rigid bodies in the same physics space.

Joints include ConeJoint, HingeJoint, Point2PointJoint, and SixDofJoint.

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	collisionBetweenLinkedBodys
protected PhysicsRigidBody	nodeA one of the connected rigid bodies
protected PhysicsRigidBody	nodeB the other connected rigid body
protected long	objectId Unique identifier of the Bullet constraint.
protected Vector3f	pivotA local offset of this joint's connection point in node A
protected Vector3f	pivotB local offset of this joint's connection point in node B

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	PhysicsJoint() No-argument constructor needed by SavableClassUtil.
	PhysicsJoint(PhysicsRigidBody nodeA, PhysicsRigidBody nodeB, Vector3f pivotA, Vector3f pivotB) Instantiate a PhysicsJoint.

Method Summary

Modifier and Type	Method and Description
void	destroy() Destroy this joint and remove it from the joint lists of its connected bodies.
protected void	finalize() Finalize this physics joint just before it is destroyed.
float	getAppliedImpulse() Read the magnitude of the applied impulse.
PhysicsRigidBody	getBodyA() Access the 1st body specified in during construction.
PhysicsRigidBody	getBodyB() Access the 2nd body specified in during construction.
long	getObjectId() Read the id of the Bullet constraint.
Vector3f	getPivotA() Access the local offset of the joint connection point in node A.
Vector3f	getPivotB() Access the local offset of the joint connection point in node A.
boolean	isCollisionBetweenLinkedBodys() Test whether collisions are allowed between the linked bodies.
void	read(JmeImporter im) De-serialize this joint, for example when loading from a J3O file.
void	setCollisionBetweenLinkedBodys(boolean collisionBetweenLinkedBodys) Enable or disable collisions between the linked bodies.
void	write(JmeExporter ex) Serialize this joint, for example when saving to a J3O file.

Methods inherited from class java.lang.Object

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

Field Detail

objectId

protected long objectId

Unique identifier of the Bullet constraint. Constructors are responsible for setting this to a non-zero value. After that, the id never changes.

nodeA

protected PhysicsRigidBody nodeA

one of the connected rigid bodies

nodeB

protected PhysicsRigidBody nodeB

the other connected rigid body

pivotA

protected Vector3f pivotA

local offset of this joint's connection point in node A

pivotB

protected Vector3f pivotB

local offset of this joint's connection point in node B

collisionBetweenLinkedBodys

protected boolean collisionBetweenLinkedBodys

Constructor Detail

PhysicsJoint

protected PhysicsJoint()

No-argument constructor needed by SavableClassUtil. Do not invoke directly!

PhysicsJoint

public PhysicsJoint(PhysicsRigidBody nodeA,
                    PhysicsRigidBody nodeB,
                    Vector3f pivotA,
                    Vector3f pivotB)

Instantiate a PhysicsJoint. To be effective, the joint must be added to the physics space of the two bodies. Also, the bodies must be dynamic and distinct.

Parameters:

nodeA - the 1st body connected by the joint (not null, alias created)

nodeB - the 2nd body connected by the joint (not null, alias created)

pivotA - local offset of the joint connection point in node A (not null, alias created)

pivotB - local offset of the joint connection point in node B (not null, alias created)

Method Detail

getAppliedImpulse

public float getAppliedImpulse()

Read the magnitude of the applied impulse.

Returns:

impulse

getObjectId

public long getObjectId()

Read the id of the Bullet constraint.

Returns:

the unique identifier (not zero)

isCollisionBetweenLinkedBodys

public boolean isCollisionBetweenLinkedBodys()

Test whether collisions are allowed between the linked bodies.

Returns:

true if collision are allowed, otherwise false

setCollisionBetweenLinkedBodys

public void setCollisionBetweenLinkedBodys(boolean collisionBetweenLinkedBodys)

Enable or disable collisions between the linked bodies. The joint must be removed from and added to PhysicsSpace for this change to be effective.

Parameters:

collisionBetweenLinkedBodys - true → allow collisions, false → prevent them

getBodyA

public PhysicsRigidBody getBodyA()

Access the 1st body specified in during construction.

Returns:

the pre-existing body

getBodyB

public PhysicsRigidBody getBodyB()

Access the 2nd body specified in during construction.

Returns:

the pre-existing body

getPivotA

public Vector3f getPivotA()

Access the local offset of the joint connection point in node A.

Returns:

the pre-existing vector (not null)

getPivotB

public Vector3f getPivotB()

Access the local offset of the joint connection point in node A.

Returns:

the pre-existing vector (not null)

destroy

public void destroy()

Destroy this joint and remove it from the joint lists of its connected bodies.

write

public void write(JmeExporter ex)
           throws java.io.IOException

Serialize this joint, for example when saving to a J3O file.

Specified by:

write in interface Savable

Parameters:

ex - exporter (not null)

Throws:

java.io.IOException - from exporter

read

public void read(JmeImporter im)
          throws java.io.IOException

De-serialize this joint, for example when loading from a J3O file.

Specified by:

read in interface Savable

Parameters:

im - importer (not null)

Throws:

java.io.IOException - from importer

finalize

protected void finalize()
                 throws java.lang.Throwable

Finalize this physics joint just before it is destroyed. Should be invoked only by a subclass or by the garbage collector.

Overrides:

finalize in class java.lang.Object

Throws:

java.lang.Throwable - ignored by the garbage collector