---
title: contactDelegate
framework: scenekit
role: symbol
role_heading: Instance Property
path: scenekit/scnphysicsworld/contactdelegate
---

# contactDelegate

A delegate that is called when two physics bodies come in contact with each other.

## Declaration

```swift
weak var contactDelegate: (any SCNPhysicsContactDelegate)? { get set }
```

## Discussion

Discussion A contact is created when two physics bodies overlap and one of the physics bodies has a collisionBitMask property that overlaps with the other body’s categoryBitMask property.

## See Also

### Detecting Contacts Between Physics Bodies

- [contactTestBetween(_:_:options:)](scenekit/scnphysicsworld/contacttestbetween(_:_:options:).md)
- [contactTest(with:options:)](scenekit/scnphysicsworld/contacttest(with:options:).md)