[=ACDC;546323]
4.12.2 Bug Roughness pls FIX problem, in 4.11 good work materials…
http://s017.radikal.ru/i402/1606/3b/c4855bf292e7.jpg
http://s019.radikal.ru/i630/1606/6d/2766774cd1ae.jpg
http://s017.radikal.ru/i422/1606/5f/aefc1945b54d.jpg
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You have to activate the High Precision Normals. You can find the option in Project settings->Rendering->Optimizations->GBuffer Format