I have a metallic and smoothness map. The metallic is in the red channel, the smoothness is in the alpha channel. (This map is used in a Unity 3D project, by the Standard shader).
The values in the map are as so:
A: 0 - Not smooth; 255 - Smooth R: 0 - Not metallic; 255 - Metallic
I have the metallic value working now I believe.
I need to invert the alpha (smoothness) channel somehow as the 'Principled BSDF' shader expects roughness. What is the best way to do this?
Here is my node setup: