[Therion] Joining surveys at a curved/sloping pitch

[Tarquin Wilton-Jones]

>     if they are later (or simultaneously) used in maps
>     that do not have the lower level passage displayed, they end up with
>     an inappropriate white (non-passage) space in a location where there
>     clearly should be passage (ie the pit).


Indeed, though I did come up with a solution for that, in the form of a
filler scrap at that location which is used when offsetting maps. It's a
messy solution though, and it would be better not to need it.

>     Similarly, scraps with holes cut-out wreak havoc with the loch models.


Interesting! Thanks for sharing that one, I hadn't noticed until you said.

>     Perhaps a way forward would be a feature whereby a passage fill area
>     be defined that is completely transparent to show any scraps that
>     happen to pass below it.


Genius! I really want this feature. Don't know if it is possible, but I
want it anyway.