Houdini 20.5 Nodes Copernicus nodes

Fractal Noise Copernicus node

Generates fractal noise.

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This operation generates a noise pattern using a fractal approach. The same underlying noise is sampled at increasing frequencies and mixed together.

Parameters

Signature

The layer type that the source accepts.

See Signatures for more information.

Range

Amplitude

Overall scale of the noise, applied before the center adjustment.

Note that layers can store negative numbers and values above one, so this may result in out of bound values, a Clamp COP can be used to enforce the range afterwards if necessary.

Center

The center of the output noise range.

Contrast

Applies a contrast to the noise prior to the amplitude and center. This can be used to make the noise more extreme without exceeding the 0 to 1 range.

Pattern

Noise Type

This controls the underlying noise function that is sampled iteratively to generate the fractal noise.

Torus

This is 4d simplex noise evaluated on a flat torus. This allows it to be periodic by construction, so unlike other noises, will not clamp or round settings to enforce periodicness.

Perlin

Perlin noise on a regular grid.

Worley Cellular F1

The worley noise’s primary distance value. This is the distance to the closest worley point. This creates a cell-like noise.

Worley Cellular F2-F1

The difference between the second closest and closest points in a worley noise. This results in a cell border-like noise.

White (Random)

Each noise element is given a constant but random value.

Per Component

Compute a separate noise for each channel of the output. If not set, the output will be grayscale even for non-Mono layers.

Metric

Worley noises can define different metrics for computing the distance to a point.

Euclidean

The usual L2 distance metric. This results in circular shapes.

Manhattan

The maximum of the two axial distances, this results in diamond shapes.

Chebyshev

The sum of the two axial distances. This results in square shapes.

Element Size

The size, in image coordinates, of the basic element of the noise.

Element Scale

Per-axis scaling of the element size for anistropic noise.

Offset

Offset of the noise function in image coordinates.

Tile Size

The size of a single tile of noise. The noise will repeat periodically in this size. This size is in image coordinates, so the default is for the entire default canoncial image. If you have a non-square image this should match the aspect ratio.

Because options like element size and lacunarity must meet certain conditions for the noise to be tileable, if this is enabled they will be rounded or clamped to valid values.

3D Noise

Evaluate the noise in a 3d space, with the first two dimensions being the location in the image, and the third being controlled separately.

3D Noise

Animate

Implicitly add time to the third coordinate.

Pulse Length

The feature size of the noise in the third dimension. This is the rate at which the noise will switch appearances.

Time Offset

Fixed offset for evaluating the noise.

Time Scale

Scale the computed time by this amount.

Loop Length (sec)

Make the noise periodic in time. This is the time in seconds to repeat at. This will clamp other options to enforce periodicity.

Fractal

Max Octaves

How many times to scale add together the noise.

Lacunarity

The amount to scale the noise for each iteration. Rounded to an integer value for periodic noise.

Roughness

The amount to scale the amplitude of each successive noise.

Inputs

size_ref

A representative layer that determines the size of the output image and controls the metadata.

pos

Rather than using the pixel’s image coordinates for the noise, use the value in this UV layer.

time

Each pixel will use this Mono layer’s value for the time.

Outputs

noise

The computed noise

See also

Copernicus nodes