Validator: please issue WARNING or ERROR for wrong coastline direction

[skela]

Currently, Validator checks coastline direction (land on the left side, sea on the right side of the line) only in the INFO level, which is not enabled by default.

Errors in coastline data can make rendering tools such as mkgmap --generate-sea misbehave seriously. In my humble opinion, the correctness of modified natural=coastline ways should be checked on every upload.

[stoecker]

The info level means that there are many false positives. Checking coastline is very error-prone, so we can't raise the level.

[skela]

Sorry, I fail to see what is error-prone about checking that an island defined as a single way with natural=coastline has the right direction.

On a related note, the coastline checks already seem to take the bounding box into account. I no longer see bogus complaints about unclosed coastline when the unclosed end is outside the bounding box.

[bastiK]

stoecker: can you elaborate?

[stoecker]

In general there have been too many warnings causing the info level. Maybe we can extract one warning into a higher level, but this needs testing.

[simon04]

Do we expect loads of false positives when raising "Reversed coastline: land not on left side" to the warning level?

[simon04]

In [4505/josm]:

fix #5954 - validator: issue warning for wrong coastline/land direction