Metals in UE4?

zombie420

I have a PBR material that's using spec/gloss instead of metallic/ roughness. I inverted the gloss map with a OneMinus node and the spec should be just plug and play right, assuming it's PBR accurate? I've been testing it in Marmoset to make sure. 

Except the metal parts don't look metallic at all. What am I doing wrong?

leleuxart

UE4 doesn't really use spec/gloss. It's meant to use metallic/roughness. The spec doesn't work as you think. https://docs.unrealengine.com/latest/INT/Resources/ContentExamples/MaterialNodes/1_3/

musashidan

A spec map is like a reflection map. A roughness map is the invert of a reflection glossiness map. 2 completely different maps.

zombie420

Thanks Leluxart, replacing spec with metalness map now! And you're right, that doc showed exactly what my problem is.

Musashidan, I have a spec and a gloss map. I used the Unreal's OneMinus node in the material editor to invert my gloss map. But per Leleuxart's suggestion, will be swapping out the specular.

musashidan

Sorry, missed the 1- bit.

There is a way to convert spec/gloss  to metal/rough. Haven't looked  into it though, but I know the blokes at gametextures.com converted a lot of their map across.