com.badlogic.gdx.physics.box2d.joints.PrismaticJointDef Maven / Gradle / Ivy
/*******************************************************************************
* 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;
/** 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. */
public class PrismaticJointDef extends JointDef {
public PrismaticJointDef () {
type = JointType.PrismaticJoint;
}
/** Initialize the bodies, anchors, axis, and reference angle using the world anchor and world axis. */
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));
referenceAngle = bodyB.getAngle() - bodyA.getAngle();
}
/** 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);
/** The constrained angle between the bodies: body2_angle - body1_angle. */
public float referenceAngle = 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 maxMotorForce = 0;
/** The desired motor speed in radians per second. */
public float motorSpeed = 0;
}