---
title: "init(body:anchor:)"
framework: scenekit
role: symbol
role_heading: Initializer
path: "scenekit/scnphysicsballsocketjoint/init(body:anchor:)"
---

# init(body:anchor:)

Creates a ball and socket joint that anchors a single physics body in space and allows it to rotate freely around an anchor point.

## Declaration

```swift
convenience init(body: SCNPhysicsBody, anchor: SCNVector3)
```

## Parameters

- `body`: The physics body to be controlled by the joint.
- `anchor`: The point the body pivots around, relative to the node containing it.

## Return Value

Return Value A new ball-and-socket-joint behavior.

## Discussion

Discussion For a behavior to take effect, add it to the physics simulation by calling the addBehavior(_:) method on your scene’s SCNPhysicsWorld object. The physics bodies constrained by the joint must be attached to nodes in the scene.

## See Also

### Creating a Ball and Socket Joint

- [init(bodyA:anchorA:bodyB:anchorB:)](scenekit/scnphysicsballsocketjoint/init(bodya:anchora:bodyb:anchorb:).md)