content: /*
   * FXGL - JavaFX Game Library. The MIT License (MIT).
   * Copyright (c) AlmasB (almaslvl@gmail.com).
   * See LICENSE for details.
   */
  /*
   * JBox2D - A Java Port of Erin Catto's Box2D
   * 
   * JBox2D homepage: http://jbox2d.sourceforge.net/
   * Box2D homepage: http://www.box2d.org
   * 
   * This software is provided 'as-is', without any express or implied
   * warranty.  In no event will the authors be held liable for any damages
   * arising from the use of this software.
   * 
   * Permission is granted to anyone to use this software for any purpose,
   * including commercial applications, and to alter it and redistribute it
   * freely, subject to the following restrictions:
   * 
   * 1. The origin of this software must not be misrepresented; you must not
   * claim that you wrote the original software. If you use this software
   * in a product, an acknowledgment in the product documentation would be
   * appreciated but is not required.
   * 2. Altered source versions must be plainly marked as such, and must not be
   * misrepresented as being the original software.
   * 3. This notice may not be removed or altered from any source distribution.
   */
  
  package com.almasb.fxgl.physics.box2d.dynamics.joints;
  
  import com.almasb.fxgl.core.math.Vec2;
  import com.almasb.fxgl.physics.box2d.dynamics.Body;
  import com.almasb.fxgl.physics.box2d.dynamics.World;
  
  /**
   * Revolute joint definition. This requires defining an anchor point where the bodies are joined.
   * The definition uses local anchor points so that the initial configuration can violate the
   * constraint slightly. You also need to specify the initial relative angle for joint limits. This
   * helps when saving and loading a game. The local anchor points are measured from the body's origin
   * rather than the center of mass because:<br/>
   * <ul>
   * <li>you might not know where the center of mass will be.</li>
   * <li>if you add/remove shapes from a body and recompute the mass, the joints will be broken.</li>
   * </ul>
   */
  public final class RevoluteJointDef extends JointDef<RevoluteJoint> {
  
      /**
       * The local anchor point relative to body1's origin.
       */
      public Vec2 localAnchorA = new Vec2();
  
      /**
       * The local anchor point relative to body2's origin.
       */
      public Vec2 localAnchorB = new Vec2();
  
      /**
       * The body2 angle minus body1 angle in the reference state (radians).
       */
      public float referenceAngle = 0f;
  
      /**
       * A flag to enable joint limits.
       */
      public boolean enableLimit = false;
  
      /**
       * The lower angle for the joint limit (radians).
       */
      public float lowerAngle = 0f;
  
      /**
       * The upper angle for the joint limit (radians).
       */
      public float upperAngle = 0f;
  
      /**
       * A flag to enable the joint motor.
       */
      public boolean enableMotor = false;
  
      /**
       * The desired motor speed. Usually in radians per second.
       */
      public float motorSpeed = 0f;
  
      /**
       * The maximum motor torque used to achieve the desired motor speed. Usually in N-m.
       */
      public float maxMotorTorque = 0f;
  
      /**
       * Initialize the bodies, anchors and reference angle using the anchor in world coordinates.
       */
      public void initialize(Body b1, Body b2, Vec2 anchor) {
          setBodyA(b1);
          setBodyB(b2);
          b1.getLocalPointToOut(anchor, localAnchorA);
          b2.getLocalPointToOut(anchor, localAnchorB);
  
          referenceAngle = b2.getAngle() - b1.getAngle();
      }
  
      @Override
      protected RevoluteJoint createJoint(World world) {
          return new RevoluteJoint(world.getPool(), this);
      }
  }
  