In a metallic-roughness workflow, metallic values switch the shading model between non-metal and metal behavior, with intermediate values mainly used at blended boundaries.
- Typical values
- Mostly 0 or 1
- Non-metal
- 0
- Metal
- 1
- glTF packing
- Blue channel
Metalness describes the material
Paint, plastic, wood, and bare metal should not share the same metallic value just because they are glossy. Use roughness for polish and metallic for material class.
Look for material-boundary errors
Generated maps can leak metallic values across painted edges or mixed materials. An isolated view makes those transitions easier to diagnose.