after sone agony i am starting to understand the sss a bit better. i was going for a deep canyon view, obut changed to a mt view with a lake far below. to achieve that i used 2 heightfields 1 at normal elevation the otherrfac -1000 feet below to create the lake area and 2 alpine shaders for distant mts my road surface is the last shader in the chain, but while i see the outline. i am not getting the tarmac- road to appear. any help advice greatly appreciated
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It's hard to see what you're doing wrong from this view, but in principle masking (blending) with a sss in the last node, and adding the tarmac as a child to such a blended/masked surface shader should work. Although I would set it up completely different. But what is the PF doing in the input of that SSS?