/*******************************************************************************
 * 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;

/**
 * Line 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.
 */
public class LineJointDef extends JointDef {
	public LineJointDef () {
		type = JointType.LineJoint;
	}

	/**
	 * Initialize the bodies, anchors, axis, and reference angle using the world anchor and world axis.
	 */
	public void initialize (Body bodyA, Body bodyB, Vector2 anchor, Vector2 axis) {
		this.bodyA = bodyA;
		this.bodyB = bodyB;
		localAnchorA.set(bodyA.getLocalPoint(anchor));
		localAnchorB.set(bodyB.getLocalPoint(anchor));
		localAxisA.set(bodyA.getLocalVector(axis));
	}

	/**
	 * 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 local translation axis in body1.
	 */
	public final Vector2 localAxisA = new Vector2(1.0f, 0);

	/**
	 * Enable/disable the joint limit.
	 */
	public boolean enableLimit = false;

	/**
	 * The lower translation limit, usually in meters.
	 */
	public float lowerTranslation = 0;

	/**
	 * The upper translation limit, usually in meters.
	 */
	public float upperTranslation = 0;

	/**
	 * Enable/disable the joint motor.
	 */
	public boolean enableMotor = false;

	/**
	 * The maximum motor torque, usually in N-m.
	 */
	public float maxMotorForce = 0;

	/**
	 * The desired motor speed in radians per second.
	 */
	public float motorSpeed = 0;
}