The opacity is droved by some simple maths build around “absoluteWorldPosition” and “DistanceToNearestSurface”…
But when I just input a constant 0 to the opacity mask, the unwanted shadows disappears… So the problem is in deed here :
I already try to tweak the absoluteWorldPosition node withe the different settings I can see but the shadows still here…
Maybe will I make something with a if node and give the mask a 1 or 0 constant value but it seams very strange to me that this isn’t working normaly…
EDIT : I did the test with the if node but the shadows remains when opacity mask is set to 0… It’s definitly the presence of the worldPosition and distance to nearest surface that cause the trouble but I don’t see a way to get rid of them and I want to understand the problem 