Rock - Photogrammetry based Environment Texture
I captured this surface to get generic rock material I can apply to medium size generic rocks.
The rock I picked to capture surface from was quite big but even thou it had not enough surface to let me capture full 180x180cm wide area. In result I captured as much as I could hoping the Artomatix will do it's job and fill the missing data with something reliable.
As you can see it did the job pretty well, especially it had to generate about 50% of empty space.
This is my photogrammetry workflow - still experimenting with 'Artomatix' and replaced Photoscan with Metashape (more details regarding to my workflow at: https://www.artstation.com/artwork/K0PYG)
Source location - to avoid direct sun light I picked the rock hidden in shadow
Source location - the rock I captured
Source location - my shoe as a scale reference
The reference image with the Color Checker included - used to calibrate color and tweak white balance in PhotoLab2
Metashape - surface reconstruction based on 29 images
ZBrush - builiding lowpoly model for baking. Since I wanted to cover 180cm by 180cm, and rock itself wasnt big enough, I just covered empty space hoping Artomatix guess and will fill it with proper data based on existing one.
Artomatix - I masked area without information telling Artomatix to ignore it and fill it with something based on whats left. As you can see, artiffical intelligence did here super awesome job.
Substance Designer - I used SD to process final tweaks - I removed ao shadows from albedo map using AO cancellation node driven by Ambient Occlusion map and I slightly tweaked Roughness map.