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/*
* The MIT License (MIT)
*
* FXGL - JavaFX Game Library
*
* Copyright (c) 2015-2017 AlmasB ([email protected])
*
* 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.
*/
/**
* Created at 12:11:41 PM Jan 23, 2011
*/
package org.jbox2d.dynamics.joints;
import com.almasb.fxgl.core.math.Vec2;
import org.jbox2d.common.JBoxSettings;
import org.jbox2d.dynamics.Body;
/**
* Pulley joint definition. This requires two ground anchors, two dynamic body anchor points, and a
* pulley ratio.
*
* @author Daniel Murphy
*/
public class PulleyJointDef extends JointDef {
/**
* The first ground anchor in world coordinates. This point never moves.
*/
public Vec2 groundAnchorA;
/**
* The second ground anchor in world coordinates. This point never moves.
*/
public Vec2 groundAnchorB;
/**
* The local anchor point relative to bodyA's origin.
*/
public Vec2 localAnchorA;
/**
* The local anchor point relative to bodyB's origin.
*/
public Vec2 localAnchorB;
/**
* The a reference length for the segment attached to bodyA.
*/
public float lengthA;
/**
* The a reference length for the segment attached to bodyB.
*/
public float lengthB;
/**
* The pulley ratio, used to simulate a block-and-tackle.
*/
public float ratio;
public PulleyJointDef() {
super(JointType.PULLEY);
groundAnchorA = new Vec2(-1.0f, 1.0f);
groundAnchorB = new Vec2(1.0f, 1.0f);
localAnchorA = new Vec2(-1.0f, 0.0f);
localAnchorB = new Vec2(1.0f, 0.0f);
lengthA = 0.0f;
lengthB = 0.0f;
ratio = 1.0f;
collideConnected = true;
}
/**
* Initialize the bodies, anchors, lengths, max lengths, and ratio using the world anchors.
*/
public void initialize(Body b1, Body b2, Vec2 ga1, Vec2 ga2, Vec2 anchor1, Vec2 anchor2, float r) {
bodyA = b1;
bodyB = b2;
groundAnchorA = ga1;
groundAnchorB = ga2;
localAnchorA = bodyA.getLocalPoint(anchor1);
localAnchorB = bodyB.getLocalPoint(anchor2);
Vec2 d1 = anchor1.sub(ga1);
lengthA = d1.length();
Vec2 d2 = anchor2.sub(ga2);
lengthB = d2.length();
ratio = r;
assert (ratio > JBoxSettings.EPSILON);
}
}