com.badlogic.gdx.physics.box2d.joints.WheelJointDef Maven / Gradle / Ivy

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This project is a higher-order fork of a box2d binding.
There is a newer version: 1.3.0
/*******************************************************************************
 * 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;

/**
 * Wheel 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 WheelJointDef extends JointDef {
  public WheelJointDef() {
    type = JointType.WheelJoint;
  }

  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, 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 maxMotorTorque = 0;

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

  /**
   * Suspension stiffness. Typically in units N/m.
   */
  public float stiffness = 0;

  /**
   * Suspension damping. Typically in units of N*s/m.
   */
  public float damping = 0;
}