org.jbox2d.collision

Class ManifoldPoint

java.lang.Object

org.jbox2d.collision.ManifoldPoint

public class ManifoldPoint
extends java.lang.Object

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 local point usage depends on the manifold type:

• e_circles: the local center of circleB
• e_faceA: the local center of cirlceB or the clip point of polygonB
• e_faceB: the clip point of polygonA

This structure is stored across time steps, so we keep it small.
Note: the impulses are used for internal caching and may not provide reliable contact forces, especially for high speed collisions.

Field Summary

Fields

Modifier and Type	Field and Description
ContactID	id uniquely identifies a contact point between two shapes
Vec2	localPoint usage depends on manifold type
float	normalImpulse the non-penetration impulse
float	tangentImpulse the friction impulse

Constructor Summary

Constructors

Constructor and Description
ManifoldPoint() Blank manifold point with everything zeroed out.
ManifoldPoint(ManifoldPoint cp) Creates a manifold point as a copy of the given point

Method Summary

Modifier and Type	Method and Description
void	set(ManifoldPoint cp) Sets this manifold point form the given one

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

localPoint

public final Vec2 localPoint

usage depends on manifold type

normalImpulse

public float normalImpulse

the non-penetration impulse

tangentImpulse

public float tangentImpulse

the friction impulse

id

public final ContactID id

uniquely identifies a contact point between two shapes

Constructor Detail

ManifoldPoint

public ManifoldPoint()

Blank manifold point with everything zeroed out.

ManifoldPoint

public ManifoldPoint(ManifoldPoint cp)

Creates a manifold point as a copy of the given point

Parameters:

cp - point to copy from

Method Detail

set

public void set(ManifoldPoint cp)

Sets this manifold point form the given one

Parameters:

cp - the point to copy from