This property determines which parts of the surface are metal and are non-metal. A metalness map is a grayscale image where black pixels correspond to non-metals and white pixels correspond to metals.

Metals only reflect light the same color as the metal, and they reflect much more light than non-metals. Most materials in the real world can be categorized either metals or non-metals. For this reason, most pixels in a metalness map will be either pure black or pure white. Values in between are typically used to simulate dirt or grunge on top of an underlying metal area.

Here’s an example of a piece of metal with a layer of paint on top. Most paints are non-metallic, so the metalness map is black everywhere except on unpainted metal parts and spots where the paint has chipped away and the underlying metal is visible.

Note

• When Lighting/EnvironmentSpecularScale is 0, metalness has no effect. For the most realistic reflections, setting EnvironmentSpecularScale and Lighting/EnvironmentDiffuseScale to 1, and Lighting/Ambient and Lighting/OutdoorAmbient to (0,0,0) is recommended.