MotorJointDef.java

/*
 * The MIT License (MIT)
 *
 * FXGL - JavaFX Game Library
 *
 * Copyright (c) 2015-2017 AlmasB (almaslvl@gmail.com)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package org.jbox2d.dynamics.joints;

import com.almasb.fxgl.core.math.Vec2;
import org.jbox2d.dynamics.Body;

/**
 * Motor joint definition.
 *
 * @author dmurph
 */
public class MotorJointDef extends JointDef {
    /**
     * Position of bodyB minus the position of bodyA, in bodyA's frame, in meters.
     */
    public final Vec2 linearOffset = new Vec2();

    /**
     * The bodyB angle minus bodyA angle in radians.
     */
    public float angularOffset;

    /**
     * The maximum motor force in N.
     */
    public float maxForce;

    /**
     * The maximum motor torque in N-m.
     */
    public float maxTorque;

    /**
     * Position correction factor in the range [0,1].
     */
    public float correctionFactor;

    public MotorJointDef() {
        super(JointType.MOTOR);
        angularOffset = 0;
        maxForce = 1;
        maxTorque = 1;
        correctionFactor = 0.3f;
    }

    public void initialize(Body bA, Body bB) {
        bodyA = bA;
        bodyB = bB;
        Vec2 xB = bodyB.getPosition();
        bodyA.getLocalPointToOut(xB, linearOffset);

        float angleA = bodyA.getAngle();
        float angleB = bodyB.getAngle();
        angularOffset = angleB - angleA;
    }
}