---
title: "update(_:)"
framework: spritekit
role: symbol
role_heading: Instance Method
path: "spritekit/skscene/update(_:)"
---

# update(_:)

Tells your app to perform any app-specific logic to update your scene.

## Declaration

```swift
func update(_ currentTime: TimeInterval)
```

## Parameters

- `currentTime`: The current system time.

## Mentioned in

Getting Started with Actions Responding to Frame-Cycle Events

## Discussion

Discussion Do not call this method directly; it is called by the system exactly once per frame, so long as the scene is presented in a view and is not paused. This is the first method called when animating the scene, before any actions are evaluated and before any physics are simulated.

## See Also

### Responding to Frame-Cycle Events

- [Responding to Frame-Cycle Events](spritekit/responding-to-frame-cycle-events.md)
- [didEvaluateActions()](spritekit/skscene/didevaluateactions().md)
- [didSimulatePhysics()](spritekit/skscene/didsimulatephysics().md)
- [didApplyConstraints()](spritekit/skscene/didapplyconstraints().md)
- [didFinishUpdate()](spritekit/skscene/didfinishupdate().md)