---
title: TimedForceFalloff
framework: realitykit
role: symbol
role_heading: Structure
path: realitykit/timedforcefalloff
---

# TimedForceFalloff

A type that modulates the force strength based on how long the force effect has run.

## Declaration

```swift
struct TimedForceFalloff
```

## Overview

Overview Forces have the largest strength when the force effect starts to play and gradually decay to zero when approaching the given duration. The effect also stops playing when reaching the duration. Similar to SpatialForceFalloff, rate controls how fast the force strength decays. You can set the rate to zero to have a force effect with no temporal falloff. let noTimedFalloff = TimedFalloff(duration: 1, rate: 0)

## Topics

### Initializers

- [init(duration:rate:)](realitykit/timedforcefalloff/init(duration:rate:).md)

### Instance Properties

- [duration](realitykit/timedforcefalloff/duration.md)
- [rate](realitykit/timedforcefalloff/rate.md)

## See Also

### Force effect constraints

- [ForceEffectBounds](realitykit/forceeffectbounds.md)
- [SpatialForceFalloff](realitykit/spatialforcefalloff.md)