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The anisotropy parameter varies in [0, 1] and describes how the reflection is oriented regarding to the surface orientation. Some real-life materials are well-known anisotropic ones: CD-ROM surface or hairs and fur for example. By default, a value of 0.5 makes the material isotropic (i.e. reflections do not vary with the orientation of the surface). Make the value smaller or greater to slightly modify the way the light is reflected at the material surface.
Click and drag in the control box slider to change the orientation of the anisotropy.
The Samples value Count changes the refinement of the anisotropy significantly.
Glossiness
The glossiness parameter controls how much the reflections are blurry. The samples parameter controls the noise level of the glossy reflections. Differences in the Glossiness setting can be seen below.
Glossiness at 0.01
Glossiness at 0.05
Glossiness at 0.99
Fresnel Reflection
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