---
title: friction
framework: scenekit
role: symbol
role_heading: Type Property
path: scenekit/scnparticlesystem/particleproperty/friction
---

# friction

The particle’s friction coefficient.

## Declaration

```swift
static let friction: SCNParticleSystem.ParticleProperty
```

## Discussion

Discussion This property’s value is a floating-point scalar (an NSNumber object for particle property controllers, or a single float value for particle event or modifier blocks). The particle system’s particleFriction and particleFrictionVariation properties determine the initial friction coefficient for each particle.

## See Also

### Type Properties

- [angle](scenekit/scnparticlesystem/particleproperty/angle.md)
- [angularVelocity](scenekit/scnparticlesystem/particleproperty/angularvelocity.md)
- [bounce](scenekit/scnparticlesystem/particleproperty/bounce.md)
- [charge](scenekit/scnparticlesystem/particleproperty/charge.md)
- [color](scenekit/scnparticlesystem/particleproperty/color.md)
- [contactNormal](scenekit/scnparticlesystem/particleproperty/contactnormal.md)
- [contactPoint](scenekit/scnparticlesystem/particleproperty/contactpoint.md)
- [frame](scenekit/scnparticlesystem/particleproperty/frame.md)
- [frameRate](scenekit/scnparticlesystem/particleproperty/framerate.md)
- [life](scenekit/scnparticlesystem/particleproperty/life.md)
- [opacity](scenekit/scnparticlesystem/particleproperty/opacity.md)
- [position](scenekit/scnparticlesystem/particleproperty/position.md)
- [rotationAxis](scenekit/scnparticlesystem/particleproperty/rotationaxis.md)
- [size](scenekit/scnparticlesystem/particleproperty/size.md)
- [velocity](scenekit/scnparticlesystem/particleproperty/velocity.md)