In the past with engines that did not use PBR, I'd usually use source photographs and chop up textures in Photoshop and overlay them on a baked AO. Then I'd run Crazybump to generate the normal and specular maps. However this technique doesn't really seem effective with the new material setup in Unreal 4. What is the…
Ah just read this page again- I see IOR is reflectivity, not necessarily specular highlight. Good call. This marmoset page was one of the pages I first got my information about PBR- I just misread it.
If you want a quick and easy, PBR essentially gives you two new things to worry about- Metalness and Roughness. Metalness changes the way the specular and diffuse works. Any metallic material you feed in a "1" any nonmetallic you feed in a "0". Roughness is sort of like gloss in that it effects the tightness of the…
Important to note that your albedo stores both your diffuse and specular color/intesnity values. For non metals, the diffuse is used while a fixed reflectivity value is applied in the shader (4% linear). For metals, the diffuse is turned black in the shader while the reflectivity is set by the albedo map. The metalness map…