# GKSpheresNoiseSource A procedural noise generator whose output is a 3D field of concentric spherical shells. ``` class GKSpheresNoiseSource ``` ## Overview All noise sources generate infinite 3D fields of noise values, but this fact is especially relevant to sphere noise: by transforming a noise object in 3D, you can sample the noise in ways that “slice” through the spheres. Use this technique (combined with other noise sources and noise processing operations) to create effects such as wood-grain textures.  Like all [`GKNoiseSource`](/documentation/GameplayKit/GKNoiseSource) subclasses, a sphere noise source represents a noise generation algorithm and its parameters. To make use of a noise source, first create [`GKNoise`](/documentation/GameplayKit/GKNoise) object from it (and optionally apply operations to that noise object or combine it with other noise objects). Then create a [`GKNoiseMap`](/documentation/GameplayKit/GKNoiseMap) object from your noise object, generating a concrete field of values that you can sample from directly or visualize using the or `SKTileMap` class. ## Topics ### Creating a Noise Source [`init(frequency:)`](/documentation/GameplayKit/GKSpheresNoiseSource/init(frequency:)) Initializes a sphere noise source with the specified frequency. [`spheresNoise(withFrequency:)`](/documentation/GameplayKit/GKSpheresNoiseSource/spheresNoise(withFrequency:)) Creates a sphere noise source with the specified frequency. ### Managing Noise Generation Parameters [`frequency`](/documentation/GameplayKit/GKSpheresNoiseSource/frequency) A value that determines the size and spacing of concentric spheres. --- Copyright © 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)