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# collisionBoundingPath

The path-based shape to use for the collision bounds.

```
optional var collisionBoundingPath: UIBezierPath { get }
```

## Discussion

When the [`collisionBoundsType`](/documentation/UIKit/UIDynamicItem/collisionBoundsType) property is [`UIDynamicItemCollisionBoundsType.path`](/documentation/UIKit/UIDynamicItemCollisionBoundsType/path), the object in this property is used as the collision bounds. If your dynamic item implements the [`collisionBoundsType`](/documentation/UIKit/UIDynamicItem/collisionBoundsType) 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`](/documentation/UIKit/UIDynamicItem/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.

---

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