Package org.jbox2d.dynamics.joints

Class PrismaticJointDef

java.lang.Object

org.jbox2d.dynamics.joints.JointDef

org.jbox2d.dynamics.joints.PrismaticJointDef

public class PrismaticJointDef
extends JointDef

Prismatic joint definition. This requires defining a line of motion using an axis and an anchor point. The definition uses local anchor points and a local axis so that the initial configuration can violate the constraint slightly. The joint translation is zero when the local anchor points coincide in world space. Using local anchors and a local axis helps when saving and loading a game.

Author:

Daniel Murphy

Warning:

at least one body should be dynamic with a non-fixed rotation.

Field Summary

Fields

Modifier and Type	Field	Description
boolean	enableLimit	Enable/disable the joint limit.
boolean	enableMotor	Enable/disable the joint motor.
final Vec2	localAnchorA	The local anchor point relative to body1's origin.
final Vec2	localAnchorB	The local anchor point relative to body2's origin.
final Vec2	localAxisA	The local translation axis in body1.
float	lowerTranslation	The lower translation limit, usually in meters.
float	maxMotorForce	The maximum motor torque, usually in N-m.
float	motorSpeed	The desired motor speed in radians per second.
float	referenceAngle	The constrained angle between the bodies: body2_angle - body1_angle.
float	upperTranslation	The upper translation limit, usually in meters.

Fields inherited from class org.jbox2d.dynamics.joints.JointDef

bodyA, bodyB, collideConnected, type, userData

Constructor Summary

Constructors

Constructor	Description
PrismaticJointDef()

Method Summary

Modifier and Type	Method	Description
void	initialize(Body b1, Body b2, Vec2 anchor, Vec2 axis)	Initialize the bodies, anchors, axis, and reference angle using the world anchor and world axis.

Methods inherited from class java.lang.Object

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

Field Details

localAnchorA

public final Vec2 localAnchorA

The local anchor point relative to body1's origin.

localAnchorB

public final Vec2 localAnchorB

The local anchor point relative to body2's origin.

localAxisA

public final Vec2 localAxisA

The local translation axis in body1.

referenceAngle

public float referenceAngle

The constrained angle between the bodies: body2_angle - body1_angle.

enableLimit

public boolean enableLimit

Enable/disable the joint limit.

lowerTranslation

public float lowerTranslation

The lower translation limit, usually in meters.

upperTranslation

public float upperTranslation

The upper translation limit, usually in meters.

enableMotor

public boolean enableMotor

Enable/disable the joint motor.

maxMotorForce

public float maxMotorForce

The maximum motor torque, usually in N-m.

motorSpeed

public float motorSpeed

The desired motor speed in radians per second.

Constructor Details

PrismaticJointDef

public PrismaticJointDef()

Method Details

initialize

public void initialize(Body b1,
 Body b2,
 Vec2 anchor,
 Vec2 axis)

Initialize the bodies, anchors, axis, and reference angle using the world anchor and world axis.