com.badlogic.gdx.physics.box2d.joints
Class RevoluteJointDef

java.lang.Object
  com.badlogic.gdx.physics.box2d.JointDef
      com.badlogic.gdx.physics.box2d.joints.RevoluteJointDef

public class RevoluteJointDef
extends JointDef

Revolute joint definition. This requires defining an anchor point where the bodies are joined. The definition uses local anchor points so that the initial configuration can violate the constraint slightly. You also need to specify the initial relative angle for joint limits. This helps when saving and loading a game. The local anchor points are measured from the body's origin rather than the center of mass because: 1. you might not know where the center of mass will be. 2. if you add/remove shapes from a body and recompute the mass, the joints will be broken.

Nested Class Summary

Nested classes/interfaces inherited from class com.badlogic.gdx.physics.box2d.JointDef

JointDef.JointType

Field Summary

boolean	enableLimit A flag to enable joint limits.
boolean	enableMotor A flag to enable the joint motor.
Vector2	localAnchorA The local anchor point relative to body1's origin.
Vector2	localAnchorB The local anchor point relative to body2's origin.
float	lowerAngle The lower angle for the joint limit (radians).
float	maxMotorTorque The maximum motor torque used to achieve the desired motor speed.
float	motorSpeed The desired motor speed.
float	referenceAngle The body2 angle minus body1 angle in the reference state (radians).
float	upperAngle The upper angle for the joint limit (radians).

Fields inherited from class com.badlogic.gdx.physics.box2d.JointDef

bodyA, bodyB, collideConnected, type

Constructor Summary

RevoluteJointDef()

Method Summary

void	initialize(Body bodyA, Body bodyB, Vector2 anchor) Initialize the bodies, anchors, and reference angle using a world anchor point.

Methods inherited from class java.lang.Object

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

Field Detail

localAnchorA

public final Vector2 localAnchorA

The local anchor point relative to body1's origin.

localAnchorB

public final Vector2 localAnchorB

The local anchor point relative to body2's origin.

referenceAngle

public float referenceAngle

The body2 angle minus body1 angle in the reference state (radians).

enableLimit

public boolean enableLimit

A flag to enable joint limits.

lowerAngle

public float lowerAngle

The lower angle for the joint limit (radians).

upperAngle

public float upperAngle

The upper angle for the joint limit (radians).

enableMotor

public boolean enableMotor

A flag to enable the joint motor.

motorSpeed

public float motorSpeed

The desired motor speed. Usually in radians per second.

maxMotorTorque

public float maxMotorTorque

The maximum motor torque used to achieve the desired motor speed. Usually in N-m.

Constructor Detail

RevoluteJointDef

public RevoluteJointDef()

Method Detail

initialize

public void initialize(Body bodyA,
                       Body bodyB,
                       Vector2 anchor)

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