Marble

Category: Texture

Shader Family: Texture

Output: Color

Simulates the random veins and impurities that naturally occur in marble. It lets you create a wide range of marble types by tweaking the parameters. The marble texture is based on the two differently colored veins sandwiched between the filler material, which are then deformed using a fractal function. You can select two colors for the veins and a color for the impurities (filler) to precisely achieve any type of marble you wish.

Texture

Name	The shader's name. Enter any name you like, or leave the default.

Texture Space

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

Bump Mapping

Enable	Switches bump mapping on or off.
Use Alpha	Uses the texture's alpha channel to achieve a 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.
Step	Controls the U, V, and Z steps of a bump map. Use this parameter to "smooth" bumps or make them more jagged.

Veins

Name	The shader's name. Enter any name you like, or leave the default.
Vein Color 1	Defines the color of the first alternation.
Vein Color 2	Defines the color of the second alternating vein. Use a slightly different color than the first vein to get very realistic results.
Filler	Defines the color of the filler; i.e., the marble itself.
Width	Defines the width of the veins in the marble. The higher the value, the thicker the veins, and vice versa.
Diffusion	Controls how much the strongly pigmented vein material will diffuse into the main marble color (filler). E.g.: A very old marble has a high diffusion.

Copy Alpha to RGB

When Activated, 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.

Spots

Name	The shader's name. Enter any name you like, or leave the default.
Color	Defines the color of the naturally occurring impurities in marble. For a flawless marble, without impurities, make this color equal to the filler color.
Density	Defines the spot (impurity) density.
Bias	Defines how much the spot color will contrast with the marble filler color.
Scale	Controls the basic size of the spot (impurities). You can get realistic effects when you use smaller values, such as 0.1.

Fractal

Name	The shader's name. Enter any name you like, or leave the default.
Frequencies	Defines the frequency of the fractal in the X, Y, and Z directions. High values take longer to render.
Amplitude	Defines the base amplitude of the fractal used to calculate this texture. This parameter only applies to the amplitude of the first iteration; successive iterations may further increase the amplitude.
Ratio	Defines the amplitude of the successive iterations relative to the current one. For values less than 1, successive iterations have a lower amplitude; for values greater than 1, the iterations have a higher amplitude and the fractal becomes unbounded.
Complexity	The maximum number of noise iterations used when calculating the fractal.
Absolute	Makes the procedure use a slightly different algorithm, which introduces discontinuities into the fractal, creating the impression of turbulence.

Advanced

Name	The shader's name. Enter any name you like, or leave the default.

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. A texture's scalar parameters can be altered to create interesting effects by applying Texture Generator shaders to them. For example, the Vein Width factor can be controlled with the Fractal Texture Generator shader.

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.