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

# contactNormal

The normal vector, in scene coordinate space, of a collision between a particle and a geometry in the scene.

## Declaration

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

## Discussion

Discussion The contact normal property only applies to collision handler blocks (see the handle(_:forProperties:handler:) method and SCNParticleEvent.collision constant). Its value is a three-component vector (an array of three float values).

## 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)
- [contactPoint](scenekit/scnparticlesystem/particleproperty/contactpoint.md)
- [frame](scenekit/scnparticlesystem/particleproperty/frame.md)
- [frameRate](scenekit/scnparticlesystem/particleproperty/framerate.md)
- [friction](scenekit/scnparticlesystem/particleproperty/friction.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)