/*******************************************************************************
* 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.Joint;
import com.badlogic.gdx.physics.box2d.World;
/** A rope joint enforces a maximum distance between two points on two bodies. It has no other effect. Warning: if you attempt to
* change the maximum length during the simulation you will get some non-physical behavior. A model that would allow you to
* dynamically modify the length would have some sponginess, so I chose not to implement it that way. See b2DistanceJoint if you
* want to dynamically control length. */
public class RopeJoint extends Joint {
// @off
/*JNI
#include <Box2D/Box2D.h>
*/
private final float[] tmp = new float[2];
private final Vector2 localAnchorA = new Vector2();
private final Vector2 localAnchorB = new Vector2();
public RopeJoint (World world, long addr) {
super(world, addr);
}
public Vector2 getLocalAnchorA () {
jniGetLocalAnchorA(addr, tmp);
localAnchorA.set(tmp[0], tmp[1]);
return localAnchorA;
}
private native void jniGetLocalAnchorA (long addr, float[] anchor); /*
b2RopeJoint* joint = (b2RopeJoint*)addr;
anchor[0] = joint->GetLocalAnchorA().x;
anchor[1] = joint->GetLocalAnchorA().y;
*/
public Vector2 getLocalAnchorB () {
jniGetLocalAnchorB(addr, tmp);
localAnchorB.set(tmp[0], tmp[1]);
return localAnchorB;
}
private native void jniGetLocalAnchorB (long addr, float[] anchor); /*
b2RopeJoint* joint = (b2RopeJoint*)addr;
anchor[0] = joint->GetLocalAnchorB().x;
anchor[1] = joint->GetLocalAnchorB().y;
*/
/** Get the maximum length of the rope. */
public float getMaxLength () {
return jniGetMaxLength(addr);
}
private native float jniGetMaxLength (long addr); /*
b2RopeJoint* rope = (b2RopeJoint*)addr;
return rope->GetMaxLength();
*/
/** Set the maximum length of the rope. */
public void setMaxLength (float length) {
jniSetMaxLength(addr, length);
}
private native float jniSetMaxLength (long addr, float length); /*
b2RopeJoint* rope = (b2RopeJoint*)addr;
rope->SetMaxLength(length);
*/
}