Grass - Photogrammetry based Environment Texture
Finally I made a big step forward with the grass reconstruction. I re-processed the capture I made while ago but wasn't happy with: https://www.artstation.com/artwork/xzzkAE . The big change was in the reconstruction mode I picked and software I used for tiling and glitch removal.
Previously I used Dense Cloud as reconstruction source and Height Field projection mode. As usual with grass it gave me glitchy result but in quite reasonable time. My PC didnt have enough RAM for full 3D Arbitrary reconstruction. I hoped that it is going to be solved by new reconstruction mode based on depth maps.. unfortunately my 16GB of RAM + 11GB of GPU RAM still wasn't enough.
This time I upgraded my PC to 64GB of RAM and used Depth Maps based reconstruction mode in highest quality. The result was very good. Still with glitches but I masked them all in Artomatix and let it to fix all that broken crap. And after 3 years of trying here it is... the first grass material I am finally almost happy with :D.
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)
Metashape - surface reconstruction based on 110 images
Metashape - Dense Cloud based reconstruction in Height Field (2,5D) mode used to create previous version of this material
Metashape - Depth Map based reconstruction in Arbitrary (3D) mode.
To make it possible I had to use PC with 64GB of RAM and 24h (without the GPU acceleration turned on.. have forgotten to switch it on :) .. next time will do)
Substance Designer - bake based on lowpoly model already made to bake this material before
Artomatix - seam and glitches removal. As you can see reconstructed surface still have a lot of reconstruction glitches. I marked as many as I was able to find using mask node and executed the seam removal node to rebuild the material without them.
Substance Designer - I used 'ao cancellation' node to remove ambient occlusion shadows from albedo map.