private void CalculateDetails()
{
_DetailsCalculated = true;
_ContactPoints = new TypeVector2 <Vector2>();
b2WorldManifold worldManifold = new b2WorldManifold();
_Contact.GetWorldManifold(worldManifold);
_Normal = worldManifold.normal.ToVector2();
_ContactPoints.x = Box2d.b2Vec2Array_getitem(worldManifold.points, 0).ToVector2();
_ContactPoints.y = Box2d.b2Vec2Array_getitem(worldManifold.points, 1).ToVector2();
}