---
title: BlendTreeInvalidNode
framework: realitykit
role: symbol
role_heading: Structure
path: realitykit/blendtreeinvalidnode
---

# BlendTreeInvalidNode

A blend tree node that’s internal only or sources from an invalid definition.

## Declaration

```swift
struct BlendTreeInvalidNode
```

## Overview

Overview This structure adopts BlendTreeNode and adds the ability to detect a node that contains neither an animation nor any branches in the blend tree. You don’t create instances of this structure. Instead, detect whether your blend-tree node matches the framework’s criteria for invalid nodes by checking the node type, as the following code demonstrates. // Get the blend tree's root node. guard let blendNode = blendTree.root as? BlendTreeBlendNode else { return } for node in blendNode.sources {     if let invalidNode = node as? BlendTreeInvalidNode {         // Respond to invalid-node criteria.

## Topics

### Configuring the blend tree invalid node

- [name](realitykit/blendtreeinvalidnode/name.md)
- [weight](realitykit/blendtreeinvalidnode/weight.md)

## Relationships

### Conforms To

- [BlendTreeNode](realitykit/blendtreenode.md)

## See Also

### Blend trees

- [BlendTreeAnimation](realitykit/blendtreeanimation.md)
- [BlendTreeNode](realitykit/blendtreenode.md)
- [BlendTreeBlendNode](realitykit/blendtreeblendnode.md)
- [BlendTreeSourceNode](realitykit/blendtreesourcenode.md)
- [BlendWeight](realitykit/blendweight.md)