Class

GKBillowNoiseSource

A procedural noise generator whose output is a type of fractal coherent noise with smooth features.

Declaration

@interface GKBillowNoiseSource : GKCoherentNoiseSource

Overview

Billow noise is similar to Perlin noise (see the GKPerlinNoiseSource class), but with more rounded features resembling natural phenomena such as treetops and hills.

Figure 1

Example output from a billow noise source

Like all GKNoiseSource subclasses, a billow noise source represents a noise generation algorithm and its parameters. To make use of a noise source, first create GKNoise object from it (and optionally apply operations to that noise object or combine it with other noise objects). Then create a GKNoiseMap object from your noise object, generating a concrete field of values that you can sample from directly or visualize using the SKTexture or SKTileMap class.

Topics

Creating a Noise Source

+ billowNoiseSourceWithFrequency:octaveCount:persistence:lacunarity:seed:

Initializes a billow noise source with the specified parameters.

- initWithFrequency:octaveCount:persistence:lacunarity:seed:

Creates a billow noise source with the specified parameters.

persistence

The rate at which successive octaves of the noise function decrease in amplitude.

Relationships

See Also

Procedural Noise

GKNoiseSource

The abstract superclass for procedural noise generators.

GKNoise

A representation of procedural noise, generated by a noise source, that you can use to process, transform, or combine noise.

GKNoiseMap

A sample of procedural noise data from which you can read noise values directly or create noise textures.

GKCoherentNoiseSource

The abstract superclass for procedural noise generators that create coherent noise.

GKPerlinNoiseSource

A procedural noise generator whose output is a type of fractal coherent noise resembling natural phenomena such as clouds and terrain.

GKRidgedNoiseSource

A procedural noise generator whose output is a type of multifractal coherent noise with sharply defined features.

GKVoronoiNoiseSource

A procedural noise generator whose output (also called Worley noise or cellular noise) divides space into discrete cells surrounding random seed points.

GKCylindersNoiseSource

A procedural noise generator whose output is a 3D field of concentric cylindrical shells.

GKSpheresNoiseSource

A procedural noise generator whose output is a 3D field of concentric spherical shells.

GKCheckerboardNoiseSource

A procedural noise generator whose output is an alternating square pattern.

GKConstantNoiseSource

A procedural noise generator that outputs a field of a single constant value.