Yes, this part with using node materials for shadow and lights looks really cool (and a bit frightening for a basic user/coordinator) like myself.
Meanwhile, about the overall effect and the use of a light map for this soft-shadows effect, I was remembering one of the old/founding PGs but couldn’t find it. I found it again this morning, in the ‘playground demo’ thread. It is this one.
‘https://playground.babylonjs.com/#H2FTZW#18’
Say you would replace all lightmap tex with BW. You would end with something like this. Quite close to your SS, isn’t it?
Though of course, this would work only for the parts that don’t move (or as per the explained above technique) I was wondering, Can you move the walls as well? like a home or shop builder?