Clipmaps using layer mask
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First, create a material as usual (reflectance, transmittance, Nd, roughness, etc). Then load the clipmap to the layer weight texture slot. White areas show the material as it is and darker areas make the layer vanish slightly. Pure black areas will make the layer completely invisible, allowing you to see the layers underneath.
If there is only one layer in the material, the black areas of the clipmap will make the object invisible.
Creating a billboard by simply mapping the Opacity of a material layer with a map
Find more clipmapped examples at the MXM Gallery.
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