/*******************************************************************************
* 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 mouse joint is used to make a point on a body track a specified world point. This a soft constraint with a maximum force.
* This allows the constraint to stretch and without applying huge forces. NOTE: this joint is not documented in the manual
* because it was developed to be used in the testbed. If you want to learn how to use the mouse joint, look at the testbed. */
public class MouseJoint extends Joint {
// @off
/*JNI
#include <Box2D/Box2D.h>
*/
public MouseJoint (World world, long addr) {
super(world, addr);
}
/** Use this to update the target point. */
public void setTarget (Vector2 target) {
jniSetTarget(addr, target.x, target.y);
}
private native void jniSetTarget (long addr, float x, float y); /*
b2MouseJoint* joint = (b2MouseJoint*)addr;
joint->SetTarget( b2Vec2(x, y ) );
*/
/** Use this to update the target point. */
final float[] tmp = new float[2];
private final Vector2 target = new Vector2();
public Vector2 getTarget () {
jniGetTarget(addr, tmp);
target.x = tmp[0];
target.y = tmp[1];
return target;
}
private native void jniGetTarget (long addr, float[] target); /*
b2MouseJoint* joint = (b2MouseJoint*)addr;
target[0] = joint->GetTarget().x;
target[1] = joint->GetTarget().y;
*/
/** Set/get the maximum force in Newtons. */
public void setMaxForce (float force) {
jniSetMaxForce(addr, force);
}
private native void jniSetMaxForce (long addr, float force); /*
b2MouseJoint* joint = (b2MouseJoint*)addr;
joint->SetMaxForce( force );
*/
/** Set/get the maximum force in Newtons. */
public float getMaxForce () {
return jniGetMaxForce(addr);
}
private native float jniGetMaxForce (long addr); /*
b2MouseJoint* joint = (b2MouseJoint*)addr;
return joint->GetMaxForce();
*/
/** Set/get the frequency in Hertz. */
public void setFrequency (float hz) {
jniSetFrequency(addr, hz);
}
private native void jniSetFrequency (long addr, float hz); /*
b2MouseJoint* joint = (b2MouseJoint*)addr;
joint->SetFrequency(hz);
*/
/** Set/get the frequency in Hertz. */
public float getFrequency () {
return jniGetFrequency(addr);
}
private native float jniGetFrequency (long addr); /*
b2MouseJoint* joint = (b2MouseJoint*)addr;
return joint->GetFrequency();
*/
/** Set/get the damping ratio (dimensionless). */
public void setDampingRatio (float ratio) {
jniSetDampingRatio(addr, ratio);
}
private native void jniSetDampingRatio (long addr, float ratio); /*
b2MouseJoint* joint = (b2MouseJoint*)addr;
joint->SetDampingRatio( ratio );
*/
/** Set/get the damping ratio (dimensionless). */
public float getDampingRatio () {
return jniGetDampingRatio(addr);
}
private native float jniGetDampingRatio (long addr); /*
b2MouseJoint* joint = (b2MouseJoint*)addr;
return joint->GetDampingRatio();
*/
}