Fractal

| Texture | Fractal | Advanced | Render Tree Usage

Category: Texture

Shader Family: Texture

Output: Color

A sophisticated fractal generator that is quite useful for bump and displacement mapping as well as color texturing. You can choose between two types of noise functions for fractal generation, as well as control various aspects of the fractal. For instance, you can use Threshold and Diffusion 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.

Texture

Texture Space

Selects the texture projection to use. See Specifying a Texture Projection [Texturing].

Bump Mapping

Enable	Switches bump mapping on or off.
Bump Map Factor	Defines how "bumpy" the bump map will be. A negative value inverts the bump inward; a positive bump map factor bumps outward.
Use Alpha	Uses the texture's alpha channel to achieve a bump map.

Fractal

Colors

Color 1	Defines the first color of the fractal pattern.
Color 2	Defines the second color of the fractal pattern.

Alpha

Copy Alpha to RGB	Multiplies the RGB channels with the alpha channel by the factor defined in the Alpha Strength parameter.
Alpha Strength	Determines the factor by which the Alpha is multiplied with the RGB channels.
Noise Type	Lets you select two noise functions to build the fractal: Perlin and Recursive.
Diffusion	Controls how much of the normal area diffuses into the threshold area.
Upper Bound	Defines at what level the fractal is clipped; i.e., the level won't get higher. This creates "flat tops" in the fractal.
Complexity	Defines the maximum number of noise iterations to use when calculating the fractal. This parameter works in conjunction with the Minimum Level value in determining the complexity of the fractal. The more constraining of the two limits is used.
Minimum Level	Defines the minimum amplitude at which iteration will occur. It is 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, hence the granularity.
Level Decay	Controls the amplitude decay of the fractal iterations. It is defined as the amplitude ratio of two successive iterations. For values less than 1, successive iterations have decreasing amplitude; for values greater than 1, they increase in amplitude 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 the Frequency Multiplier is the same as scaling down the texture by a factor of 0.5; 1.0 gives a sharp fractal texture with low detail, and 2.0 gives a more detailed and varying texture.
Threshold	Below the threshold level, the fractal will be set to black.
Time	Animates the fractal in time. This is achieved by animating the value of this parameter. If you change the value between frames, 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.

Advanced

Bump Mapping

Step	Controls the U, V, and Z steps of a bump map. Use this parameter to "smooth" bumps or make them more jagged.

Alternate

U, V, Z

Specifies whether every other copy of the repetition should be reversed so that the successive copies of the texture are alternated.

Repeats

Texture Repeats

Contains the repetition factor in X,Y, and Z. A value of 2, for example, shrinks the texture so that it fits twice in a [0..1] interval.

UV Remap

Minimum, Maximum

Determines the remapping of the texture image. For a 2D image, only X and Y are used.

Render Tree Usage

Color parameters can be connected to other textures or image processing shaders. For example, you can connect a different texture to Color 1 and Color 2 to create a blend of image clips.

A texture's scalar parameters can be altered to create interesting effects by applying Texture Generator shaders to them.

A texture shader has limitless capabilities in a render tree. It can texture an object, be used as a camera or light projection, define bump or displacement maps, or be blended with any number of other textures to create any effect.

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