Fractal

Category: Texture Generators

Shader Family: Texture

Output: Scalar

Creates a fractalized texture in 3D. The Fractal 3D texture is a sophisticated fractal generator, which is quite useful for bump and displacement mapping as well as color texturing. You can also choose between two types of noise functions for fractal generation. In addition, various aspects of the fractal can be controlled. For instance, you can use the Threshold and Diffusion parameters to clip the fractal at a certain level and diffuse it into the threshold area, allowing for a smooth overlay onto other textures.

Name	The shader's name. Enter any name you like, or leave the default.
Coordinates	Defines the U, V, and Z texture coordinates of the texture.
Diffusion	Controls how much of the normal area diffuses into the threshold area.
Upper Bound	Defines the upper level at which the fractal is clipped. This creates "flat tops" in the fractal.
Noise Type	For selecting two noise functions for building the fractal: Perlin-type noise function and a recursive function with slightly different characteristics.
Complexity	Defines the maximum number of noise iterations to use when calculating the fractal. Works in conjunction with the Minimum Level value in determining the complexity of the fractal. The more constraining of the two limits is used.
Level Minimum	Defines the minimum amplitude at which iteration will occur. Used to determine how often the noise function is called. A value of 0.1 means that noise amplitude less than 0.1 will not be added to the fractal, and iteration will cease. This parameter can be used to control the amount of detail in the texture, or granularity.
Level Decay	Controls the amplitude decay of the fractal iterations. Defined as the amplitude ratio of two successive iterations. For values less than 1, the amplitude of successive iterations decreases; for values greater than 1, the amplitude of successive iterations increases and the fractal becomes unbounded.
Frequency Multiplier	Controls the frequency multiplier for subsequent iterations. Fractal frequency is simply the inverse of scale. Doubling the frequency with this parameter is the same as scaling down the texture by a factor of 0.5. Therefore, a value of 1 gives a sharp fractal texture with low detail, and a value of 2 gives a more detailed and varying texture.
Threshold	Below the threshold level, the fractal should be set to black.
Time	Animates the fractal in time by animating the value of this parameter. Changing the value between frames and the fractal texture will change in a continuous manner between these frames.
Absolute	Makes the fractal procedure use a slightly different algorithm, which causes discontinuities in the fractal itself. This creates the impression of turbulence.

Render Tree Usage

Use this shader to drive a parameter with a texture effect anywhere in a render tree. This shader generates a texture that can be used as an Intensity value, a Scale value, or to drive any scalar Surface shader parameter (IOR, Bumpmap Factor, etc.).

The Coordinates parameter can be driven (connected) with a Texture Space Generator shader.

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