---
title: defaultSource
framework: realitykit
role: symbol
role_heading: Instance Property
path: realitykit/animationstateprotocol/defaultsource
---

# defaultSource

The previous blend stage value.

## Declaration

```swift
var defaultSource: Self.ValueType? { get }
```

## Discussion

Discussion The default source is the value output from the previous blend stage, and initialized with defaultTarget for the first stage.