Struct noise::Fbm

pub struct Fbm<T> {
    pub octaves: usize,
    pub frequency: f64,
    pub lacunarity: f64,
    pub persistence: f64,
    /* private fields */
}

Noise function that outputs fBm (fractal Brownian motion) noise.

fBm is a monofractal method. In essence, fBm has a constant fractal dimension. It is as close to statistically homogeneous and isotropic as possible. Homogeneous means “the same everywhere” and isotropic means “the same in all directions” (note that the two do not mean the same thing).

The main difference between fractal Brownian motion and regular Brownian motion is that while the increments in Brownian motion are independent, the increments in fractal Brownian motion depend on the previous increment.

fBm is the result of several noise functions of ever-increasing frequency and ever-decreasing amplitude.

fBm is commonly referred to as Perlin noise.

Fields

octaves: usize

Total number of frequency octaves to generate the noise with.

The number of octaves control the amount of detail in the noise function. Adding more octaves increases the detail, with the drawback of increasing the calculation time.

frequency: f64

The number of cycles per unit length that the noise function outputs.

lacunarity: f64

A multiplier that determines how quickly the frequency increases for each successive octave in the noise function.

The frequency of each successive octave is equal to the product of the previous octave’s frequency and the lacunarity value.

A lacunarity of 2.0 results in the frequency doubling every octave. For almost all cases, 2.0 is a good value to use.

persistence: f64

A multiplier that determines how quickly the amplitudes diminish for each successive octave in the noise function.

The amplitude of each successive octave is equal to the product of the previous octave’s amplitude and the persistence value. Increasing the persistence produces “rougher” noise.

Implementations

impl<T> Fbm<T>

where T: Default + Seedable,

pub const DEFAULT_SEED: u32 = 0u32

pub const DEFAULT_OCTAVE_COUNT: usize = 6usize

pub const DEFAULT_FREQUENCY: f64 = 1f64

pub const DEFAULT_LACUNARITY: f64 = 2.0943951023931953f64

pub const DEFAULT_PERSISTENCE: f64 = 0.5f64

pub const MAX_OCTAVES: usize = 32usize

pub fn new(seed: u32) -> Self

pub fn set_sources(self, sources: Vec<T>) -> Self

Trait Implementations

impl<T: Clone> Clone for Fbm<T>

fn clone(&self) -> Fbm<T>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: Debug> Debug for Fbm<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T> Default for Fbm<T>

where T: Default + Seedable,

fn default() -> Self

Returns the “default value” for a type.

impl<T> MultiFractal for Fbm<T>

where T: Default + Seedable,

fn set_octaves(self, octaves: usize) -> Self

fn set_frequency(self, frequency: f64) -> Self

fn set_lacunarity(self, lacunarity: f64) -> Self

fn set_persistence(self, persistence: f64) -> Self

impl<T> NoiseFn<f64, 2> for Fbm<T>

where T: NoiseFn<f64, 2>,

2-dimensional Fbm noise

fn get(&self, point: [f64; 2]) -> f64

impl<T> NoiseFn<f64, 3> for Fbm<T>

where T: NoiseFn<f64, 3>,

3-dimensional Fbm noise

fn get(&self, point: [f64; 3]) -> f64

impl<T> NoiseFn<f64, 4> for Fbm<T>

where T: NoiseFn<f64, 4>,

4-dimensional Fbm noise

fn get(&self, point: [f64; 4]) -> f64

impl<T> Seedable for Fbm<T>

where T: Default + Seedable,

fn set_seed(self, seed: u32) -> Self

Set the seed for the function implementing the Seedable trait

fn seed(&self) -> u32

Getter to retrieve the seed from the function