At a glance, there appears to be almost no rendering performance difference vs standard normal mapping. Seems like it would be feasible in realtime engines. Baked normal maps are commonplace now in leading game titles. AR/VR stereoscopic views would make anisotropic surface effects, diffraction, etc even more obvious for those micro details and really help sell the illusion. Very interested in seeing Cars 3 in 3D to test this hypothesis...

Valve paper on it from 2015: http://media.steampowered.com/apps/valve/2015/Alex_Vlachos_A...

Scroll to the part about normal maps.

It’s an additional texture fetch on the gpu, it’s virtualy free if you discount storage costs. It’s been in games for years.

Additional texture fetch is by no means free but when the alternative is 100x SSAA you can get away with a lot.

Myself (and likely others) would be willing to pay for an offline version.