# XrHitTestStartCallback

Type alias · category: Other

Source: https://github.com/playcanvas/engine/blob/970d89f6d3bc6667f4e1f88153abd6e7e82ed52c/src/framework/xr/xr-hit-test.js#L13

Callback used by [XrHitTest#start](https://api.playcanvas.com/engine/classes/XrHitTest.md#start) and [XrInputSource#hitTestStart](https://api.playcanvas.com/engine/classes/XrInputSource.md#hitteststart).

```ts
type XrHitTestStartCallback = (err: Error | null, hitTestSource: XrHitTestSource | null) => void
```