Stairs and ramps are objects and even if the surface of a wall and an object are in line there will always be a joining line between.
The easiest way I can think of to hide it in 3D is to place a polygonal morph (line) along the join with it set to a white pen colour or maybe a similar pen colour to your surface.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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