The path-based shape to use for the collision bounds.
- iOS 9.0+
- tvOS 9.0+
collision property is
UIDynamic, the object in this property is used as the collision bounds. If your dynamic item implements the
collision property, you must also implement this property.
The path object you create must represent a convex polygon with counter-clockwise or clockwise winding, and the path must not intersect itself. The (0, 0) point of the path must be located at the
center point of the corresponding dynamic item. If the center point does not match the path’s origin, collision behaviors may not work as expected.