I would recommend these links for PBR documentation;
https://www.marmoset.co/posts/physically-based-rendering-and-you-can-too/https://www.allegorithmic.com/pbr-guideWeird to see they are not using a separate texture for AO. The post-process AO works well but most of the times you need a texture for micro-occlusion for small cracks. Some games combines the ao mask with the diffuse map but I really don't like this method (you save memory space but it's not good for PBR workflow).
Apparently they're using this algorithm for AO:
http://research.nvidia.com/sites/de...able-Ambient-Obscurance/McGuire12SAO.pdfIt doesn't use any additional texture inputs, so that's probably why there is no AO texture.
That's similar to others SSAO techniques, but with some differences. But my doubt comes because the blue channel map looks like a Cavity map (reflectance discarded. Reflectance can be controlled, usually not needed, by a constant value, default 0.5).
These days modern AO texture is more of a cavity map. Using SSAO the large AO is taken care of and you just need to worry about the smaller scale stuff in the cavities and such. What I'm trying to figure out is how they are using this map. Is most of the materials I'm exploring the blue channel is not being used.
I use Quixel for PBR texturing and they have a UE4 RMA packed export setting, I'm gonna test and see if it works.
Quixel is good too. I use Substance Painter/Designer usually, and PS if I need do something simple or hand painted.
