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# chainRootNode

The parent node of the hierarchy affected by the constraint.

```
var chainRootNode: SCNNode { get }
```

## Discussion

The root node is the highest node in the hierarchy moved by the constraint. For example, a robot arm may have two arm segments and a hand connected to a body. The upper arm is a child node of the body, the lower arm is a child node of the upper arm, and the hand is a child node of the lower arm. In this case, the upper arm is the chain root node, because the body should not move to follow the hand.

---

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