Metallicity

In Physically Based Rendering (PBR), Metallicity is a critical property of a material, which influences how it interacts with light. It's a binary property, indicating whether the material is a 'metal' or 'non-metal'. Metals have a high metallicity value (often 1), non-metals (such as wood, plastic, etc.) have a low metallicity value (often 0). Interestingly, with PBR, there exists no 'partially metal' materials ― it's an all or nothing characteristic. This property significantly impacts color handling, too, as metals derive their color from specular reflection while non-metals derive from subsurface scattering (diffuse).