Version mkgmap-r4689 was committed by gerd on Sun, 02 May 2021 merge the check-precomp-sea branch to do some basic plausibilty tests on precompiled sea data. The new file sea-check.txt contains characters s (sea), m(mixed), and l(land). Each character represents one entry in the index file that comes with precompiled sea (sea.zip) with the expected result. Tiles near the coastline have m. - If PrecompSeaGenerator is used to calculate the sea data and the index check fails a warning is printed and the program ends with rc -1. - If mkgmap is used with a "dubious" sea.zip one or more messages about the problematic areas are written and the program stops with an ExitException unless option --x-check-precomp-sea=0 is given before the first input file. The index test is normally performed once for the whole planet, so it doesn't care about the actual tile boundaries. If e.g. only a part of Australia is flooded and you create a map for the UK you'll still see the errors. http://www.mkgmap.org.uk/websvn/revision.php?repname=mkgmap&rev=4689