Production guide

Unity roughness vs smoothness

Convert roughness correctly when a Unity shader expects smoothness.

Production problem

Many Unity shaders use smoothness, which is the inverse of roughness; sending roughness directly can flip the material response.

Decision checklist

  • Check whether the material slot expects roughness or smoothness.
  • Invert roughness when feeding a smoothness input.
  • Keep AO and height as linear data maps.

Common failure cases

  • A rough concrete can become glossy if roughness is treated as smoothness.
  • Normal maps must still use Unity Normal map import type.

Production FAQ

Is smoothness equal to roughness?

No. Smoothness is usually 1 minus roughness.

Where should smoothness be packed?

It depends on the Unity shader or pipeline, so confirm URP/HDRP material requirements.