/*******************************************************************************
* Copyright 2011 See AUTHORS file.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
******************************************************************************/
package com.badlogic.gdx.physics.box2d.joints;
import com.badlogic.gdx.math.Vector2;
import com.badlogic.gdx.physics.box2d.Body;
import com.badlogic.gdx.physics.box2d.JointDef;
/** Distance joint definition. This requires defining an anchor point on both bodies and the non-zero length of the distance joint.
* The definition uses local anchor points so that the initial configuration can violate the constraint slightly. This helps when
* saving and loading a game.
* @warning Do not use a zero or short length. */
public class DistanceJointDef extends JointDef {
public DistanceJointDef () {
type = JointType.DistanceJoint;
}
/** Initialize the bodies, anchors, and length using the world anchors. */
public void initialize (Body bodyA, Body bodyB, Vector2 anchorA, Vector2 anchorB) {
this.bodyA = bodyA;
this.bodyB = bodyB;
this.localAnchorA.set(bodyA.getLocalPoint(anchorA));
this.localAnchorB.set(bodyB.getLocalPoint(anchorB));
this.length = anchorA.dst(anchorB);
}
/** The local anchor point relative to body1's origin. */
public final Vector2 localAnchorA = new Vector2();
/** The local anchor point relative to body2's origin. */
public final Vector2 localAnchorB = new Vector2();
/** The natural length between the anchor points. */
public float length = 1;
/** The mass-spring-damper frequency in Hertz. */
public float frequencyHz = 0;
/** The damping ratio. 0 = no damping, 1 = critical damping. */
public float dampingRatio = 0;
}