I admit that my test was somewhat lunatic but I took some random dataset from
Finland with 68101 polygons and converted data into MVT with default settings
which means that minzoom was 0. As a result 12196 of the source polygons were
written into the 0-level protobuf tile (in EPSG:3067 gridset) and none of the
polygons is valid. Most polygons have too few points and those which have
enough points have self-intersections.
Perhaps there should be some sort of geometry validator in the writer chain?
gdal-dev mailing list