---
title: idleDuration
framework: scenekit
role: symbol
role_heading: Instance Property
path: scenekit/scnparticlesystem/idleduration
---

# idleDuration

The duration, in seconds, of periods when the system emits no particles. Animatable.

## Declaration

```swift
var idleDuration: CGFloat { get set }
```

## Discussion

Discussion If the system’s loops property value is true, you can make the system emit particles periodically or sporadically. For example, in a looping system where the emissionDuration value is 1.0 seconds and the idleDuration value is 1.0 seconds, the system alternates between equal one-second periods of spawning and not spawning particles. You can randomize the duration with the idleDurationVariation property. Idle duration has no effect if the loops property value is false. The default value is 0.0 seconds, specifying no idle time between emissions. (That is, if the loops property value is true, the system emits particles continuously.) You can animate changes to this property’s value. See Animating SceneKit Content.

## See Also

### Managing Particle Emission Timing

- [emissionDuration](scenekit/scnparticlesystem/emissionduration.md)
- [emissionDurationVariation](scenekit/scnparticlesystem/emissiondurationvariation.md)
- [idleDurationVariation](scenekit/scnparticlesystem/idledurationvariation.md)
- [loops](scenekit/scnparticlesystem/loops.md)
- [warmupDuration](scenekit/scnparticlesystem/warmupduration.md)
- [birthRate](scenekit/scnparticlesystem/birthrate.md)
- [birthRateVariation](scenekit/scnparticlesystem/birthratevariation.md)