I’m fairly new to using PBR, especially in UE4 and we’ve just started using it for our course at university. I’m managing to figure out most things as I go along that I will need, however, one thing me and my course mates are stumped on is how exactly to mask out parts of your mesh when it comes to metalness, as parts of our models won’t be completely metal or not.
We’re pretty sure it has something to do with lerps and a black and white texture map, but we’re unsure of what nodes to connect to where and we haven’t been able to find anything online that has helped us.
Any help whatsoever would be greatly appreciated. Sorry about the noob question but we all have to start somewhere!
“I’d recommend plugging a Fresnel node into the A input on the Lerp, so that you have a slightly more realistic specular behaviour.” This is actually not good idea. UE4 automatically calculates fresnel equation for specular for you at shading stage per light which is physically more correct. So don’t mess with specular node and leave it unconnected for 90% materials.
You can also skip the lerp between the values for 99% of cases as metalness is mostly 0 or 1. using a grey scale map for roughness is where there is more space for subtlety