You may not specify attribute -outline in case of pit.
Why not? It is perfectly normal for a passage to end at a pit, and that pit therefore becomes a line that terminates a passage. I have attached a hand drawn example of how this would appear normally on a plan view (at least, this is how it would normally appear on a plan survey in the UK, such as the survey of a pothole - vertical cave - like Swinsto or Simpson's). "-outline in" does work on the pit line here for generating a PDF. But shows a warning when generating LOX. "-outline out" also works without a warning when generating LOX or when generating PDF. What I don't understand is 1. Whether "-outline out" is actually the correct thing to use when the pit line points outwards rather than inwards. 2. Why it even matters which way we draw a *wall*, if "outline out" always can pick the "correct" side to fill. Surely if it can work out the "correct" side of a pit line, it can also work out the correct side of a "wall" line, and it doesn't even matter whether the yellow tick points towards "air" or "rock". (Having to have an invisible wall on the lower scrap makes complete sense to me though, since that has to have a curved wall matching the curve of the pit line above. This is what I already use.)
