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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.
*/
package org.jbox2d.dynamics.joints;
import com.almasb.fxgl.core.math.Vec2;
import org.jbox2d.dynamics.Body;
/**
* Prismatic 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.
*
* @warning at least one body should by dynamic with a non-fixed rotation.
* @author Daniel
*
*/
public class PrismaticJointDef extends JointDef {
/**
* The local anchor point relative to body1's origin.
*/
public final Vec2 localAnchorA;
/**
* The local anchor point relative to body2's origin.
*/
public final Vec2 localAnchorB;
/**
* The local translation axis in body1.
*/
public final Vec2 localAxisA;
/**
* The constrained angle between the bodies: body2_angle - body1_angle.
*/
public float referenceAngle;
/**
* Enable/disable the joint limit.
*/
public boolean enableLimit;
/**
* The lower translation limit, usually in meters.
*/
public float lowerTranslation;
/**
* The upper translation limit, usually in meters.
*/
public float upperTranslation;
/**
* Enable/disable the joint motor.
*/
public boolean enableMotor;
/**
* The maximum motor torque, usually in N-m.
*/
public float maxMotorForce;
/**
* The desired motor speed in radians per second.
*/
public float motorSpeed;
public PrismaticJointDef() {
super(JointType.PRISMATIC);
localAnchorA = new Vec2();
localAnchorB = new Vec2();
localAxisA = new Vec2(1.0f, 0.0f);
referenceAngle = 0.0f;
enableLimit = false;
lowerTranslation = 0.0f;
upperTranslation = 0.0f;
enableMotor = false;
maxMotorForce = 0.0f;
motorSpeed = 0.0f;
}
/**
* Initialize the bodies, anchors, axis, and reference angle using the world anchor and world
* axis.
*/
public void initialize(Body b1, Body b2, Vec2 anchor, Vec2 axis) {
bodyA = b1;
bodyB = b2;
bodyA.getLocalPointToOut(anchor, localAnchorA);
bodyB.getLocalPointToOut(anchor, localAnchorB);
bodyA.getLocalVectorToOut(axis, localAxisA);
referenceAngle = bodyB.getAngle() - bodyA.getAngle();
}
}