I’m working on creating a MapRoulette challenge covering the whole planet.
The challenge asks people to review situations where someone has drawn an island (
islet) on the map but forgotten to add it as an
inner to the surrounding water body. As a result, the island doesn’t render on our maps (not on any of the maps on openstreetmap.org, anyway).
A typical example is here.
Sometimes the island does render, because it has also some other tag that renders over
water, such as
natural=wood. In those cases, I am still planning to ask mappers to add it to the multipolygon relation, because semantically it doesn’t make sense to say the island is part of the
water just because it has
wood on it. (Let me know if you disagree.)
Sometimes there are duplicate ways, sharing the same nodes, one tagged
place=island and one tagged
natural=wood. In those cases I am planning to ask the mappers to merge the two ways. (This is automatically flagged by JOSM’s validator.)
A situation that’s quite common in Canada (more than 3,000 islands if I am counting right) is where the CanVec import has created duplicate ways for wooded islands, one
natural=wood and one
place=island, that share the same nodes but they have conflicting
canvec:UUID tags. Sometimes there’s even a third copy of the way, which only serves as the
inner to the water body. In these cases the overlapping ways can’t simply be merged, the mapper would have to discard one (or both) of the CanVec tags. Example island and wood.
I’m wondering if I should include these in the MapRoulette challenge, and, if so, what to ask mappers to do.
(1) Would you like to see the overlapping
island merged? Or would you rather keep both?
(2) If you would like to see them merged, which of the CanVec tags should be kept?