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Here is where you supply a signal, either a texture or procedural pattern, to create a bump to the surface to "fake" surface details like small bumps or scratches. This means an artist doesn't have to model these tedious and often repetitious parts of a model.

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Tail Parameters

Mix

How strong the tail effect should be in a linear fashion.

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Defines the roughness of the tail, full roughness at 1.0 will stretch the furthest with 0.0 being no roughness or no length.

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Anisotropy Parameters

Anisotropy

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Controls the saturation of the dispersion

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Interior Parameters

These parameters control the bulk of a dielectric material. When you think of what makes a glass object look like it does...the color and clarity, it's the absorption.

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This defines the scattering direction of the light, it can be forward (positive) or backward (negative) scattering. A value of 0 is isotropic, in all directions.

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Shadow Parameters

Density

This controls how opaque the resulting shadow is after taking into account the above parameters controlling Fresnel, coloring, absorption, etc. A value of 0 is a fully transparent or invisible shadow.

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This sets the influence of the Fresnel setting on the shadow after a ray passes through back-facing geometry.

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Advanced Parameters

Exterior IOR

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