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One such example is Louise Nash (shaded by Yeon Kang) from Cars 3. Here you can see extensive wear of the clear coat on the paint job, which creates micro-scratches and breaks up the specular in interesting ways, also driving the anisotropy in ways which more accurately reflect the intended look-development.
© Disney/ Pixar
A crucial feature of Bump Roughness is to see micro details when objects are far from the camera. In the example above, you can see how we can get very close to the intended look-development with only 1 sample, instead of having to fire hundreds of rays to visualize the intended level of detail in the textures.
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