<!--
{
  "availability" : [
    "iOS: 8.0.0 - 26.0.0",
    "iPadOS: 8.0.0 - 26.0.0",
    "macCatalyst: 13.1.0 - 26.0.0",
    "macOS: 10.8.0 - 26.0.0",
    "tvOS: 9.0.0 - 26.0.0",
    "visionOS: 1.0.0 - 26.0.0",
    "watchOS: 3.0.0 - 26.0.0"
  ],
  "documentType" : "symbol",
  "framework" : "SceneKit",
  "identifier" : "/documentation/SceneKit/SCNPhysicsField/turbulenceField(smoothness:animationSpeed:)",
  "metadataVersion" : "0.1.0",
  "role" : "Type Method",
  "symbol" : {
    "kind" : "Type Method",
    "modules" : [
      "SceneKit"
    ],
    "preciseIdentifier" : "c:objc(cs)SCNPhysicsField(cm)turbulenceFieldWithSmoothness:animationSpeed:"
  },
  "title" : "turbulenceField(smoothness:animationSpeed:)"
}
-->

# turbulenceField(smoothness:animationSpeed:)

Creates a field that applies random forces to objects in its area of effect, with magnitudes proportional to those objects’ velocities.

```
class func turbulenceField(smoothness: CGFloat, animationSpeed speed: CGFloat) -> SCNPhysicsField
```

## Parameters

`smoothness`

The amount of randomness in the field. A value of `0.0` specifies maximum noise, and a value of `1.0` specifies no noise at all.

`speed`

The field’s variation over time. Specify `0.0` for a static field.

## Return Value

A physics field object. To use the field in a scene, attach it to the [`physicsField`](/documentation/SceneKit/SCNNode/physicsField) property of an [`SCNNode`](/documentation/SceneKit/SCNNode) object.

## Discussion

Like a noise field, a turbulence field applies forces in random directions to the objects that it affects. Unlike a noise field, a turbulence field applies a force whose magnitude is proportional to the speed of each affected object. For example, an object passing through a noise field shakes as it travels through the field, but an object passing through a turbulence field shakes more violently the faster it travels. The field’s [`strength`](/documentation/SceneKit/SCNPhysicsField/strength) property scales the magnitude of the turbulence effect.

The default [`falloffExponent`](/documentation/SceneKit/SCNPhysicsField/falloffExponent) value for a turbulence field is `0.0`, indicating that the field’s effect is constant throughout its area of effect.

---

Copyright &copy; 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)