---
title: renderCallbacks
framework: realitykit
role: symbol
role_heading: Instance Property
path: realitykit/arview/rendercallbacks-swift.property
---

# renderCallbacks

A container that holds the view’s render callbacks.

## Declaration

```swift
@MainActor @preconcurrency var renderCallbacks: ARView.RenderCallbacks { get set }
```

## Mentioned in

Applying core image filters as a postprocess effect Implementing postprocess effects using Metal compute functions

## Discussion

Discussion Render callbacks are closures RealityKit calls at predefined times. You can use render callbacks to modify the results of RealityKit’s rendering. If you assign a function or closure to any of the contained callback properties, RealityKit calls that function or closure at a predefined time. Setting the ARView/RenderCallbacks-swift.postProcess property, for example, causes RealityKit to call the assigned function or closure every frame, after RealityKit renders the scene, but before it displays it.

## See Also

### Configuring the AR session

- [session](realitykit/arview/session.md)
- [automaticallyConfigureSession](realitykit/arview/automaticallyconfiguresession.md)
- [renderOptions](realitykit/arview/renderoptions-swift.property.md)