Struct Manifold

A manifold for two touching convex Shapes. Box2D supports multiple types of contact:

Clip point versus plane with radius
Point versus point with radius (circles) The local point usage depends on the manifold type:
ShapeType.Circles: the local center of circleA
SeparationFunction.FaceA: the center of faceA
SeparationFunction.FaceB: the center of faceB Similarly the local normal usage:
ShapeType.Circles: not used
SeparationFunction.FaceA: the normal on polygonA
SeparationFunction.FaceB: the normal on polygonB We store contacts in this way so that position correction can account for movement, which is critical for continuous physics. All contact scenarios must be expressed in one of these types. This structure is stored across time steps, so we keep it small.

public struct Manifold

Fields

Not use for Type.SeparationFunction.Points

public Vector2 LocalNormal

Usage depends on manifold type

public Vector2 LocalPoint

The number of manifold points

public int PointCount

The points of contact

public FixedArray2<ManifoldPoint> Points

The type

public ManifoldType Type