Does anyone knows the rules to create SBSAR for Photoshop?

I.e  what input would work.  what atomic nodes?  Blur for example?  or distance ?  pixel processor?   Is there any templates  or presets for photoshop?

So far I fugured out it works on powerx 2  format  and acept RGB layer luminosity  as grayscale input.   what about using separate channels  , like R as greayscale and GB as 2d vector  and A as a slope ?   I seems can't find any info  and sometimes it looks like working just fine. As a nice live filter.   Other time doesn't work at all.