/*
* 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 org.jbox2d.collision;
import org.jbox2d.common.Vec2;
//Updated to rev 56->108->139 of b2Collision.h
/**
* A manifold point is a contact point belonging to a contact
* manifold. It holds details related to the geometry and dynamics
* of the contact points.
* The point is stored in local coordinates because CCD
* requires sub-stepping in which the separation is stale.
*/
public class ManifoldPoint {
/** Local position of the contact point in body1 */
public final Vec2 localPoint1;
/** Local position of the contact point in body2 */
public final Vec2 localPoint2;
/** The separation of the shapes along the normal vector */
public float separation;
/** The non-penetration force */
public float normalImpulse;
/** The friction force */
public float tangentImpulse;
/** Uniquely identifies a contact point between two shapes */
public final ContactID id;
/**
* Blank manifold point with everything zeroed out.
*/
public ManifoldPoint() {
localPoint1 = new Vec2();
localPoint2 = new Vec2();
separation = normalImpulse = tangentImpulse = 0f;
id = new ContactID();
}
/**
* Creates a manifold point as a copy of the given point
* @param cp point to copy from
*/
public ManifoldPoint(ManifoldPoint cp) {
localPoint1 = cp.localPoint1.clone();
localPoint2 = cp.localPoint2.clone();
separation = cp.separation;
normalImpulse = cp.normalImpulse;
tangentImpulse = cp.tangentImpulse;
id = new ContactID(cp.id);
}
/**
* Sets this manifold point form the given one
* @param cp the point to copy from
*/
public void set(ManifoldPoint cp){
localPoint1.set(cp.localPoint1);
localPoint2.set(cp.localPoint2);
separation = cp.separation;
normalImpulse = cp.normalImpulse;
tangentImpulse = cp.tangentImpulse;
id.set(cp.id);
}
}
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