tippecanoe keeps dropping polygons at mid level zooms

Question

Is there anyway to stop tippecanoe from dropping polygons at low/mid level zooms while keeping within the 500kb per tile size limit of mapbox uploads for an mbtiles file? We are getting a lot of polygons being dropped. We are not sure what flags to use to make this possible.

This is the command line:

tippecanoe -o polys.mbtiles \
--coalesce-smallest-as-needed \
--coalesce-densest-as-needed \
--coalesce-fraction-as-needed \
--simplify-only-low-zooms \
--no-feature-limit \
--no-tile-size-limit \
--minimum-zoom=10 \
--maximum-zoom=20 \
--calculate-feature-density

Without --no-feature-limit --no-tile-size-limit, features get dropped.

What flags are you using at the moment? Maybe include your complete command line. — Steve Bennett
tippecanoe -o polys.mbtiles \ --coalesce-smallest-as-needed \ --coalesce-densest-as-needed \ --coalesce-fraction-as-needed \ --simplify-only-low-zooms \ --no-feature-limit \ --no-tile-size-limit \ --minimum-zoom=10 \ --maximum-zoom=20 \ --calculate-feature-density \ — blg2
without --no-feature-limit \ --no-tile-size-limit, features get dropped. — blg2

Steve Bennett Steve Bennett · Accepted Answer · 2018-07-24T00:29:22

There are lots of possible solutions to prevent small polygons being dropped, depending on what the cause of the dropping is.

Remove attributes you don't need, with --include
Use --detect-shared-borders to store polygons that touch each other more efficiently.
Use --simplification=10 or higher to reduce the precision of locations.
Use --drop-smallest-as-needed so that the polygons that are dropped are the smallest ones, not randomly chosen.
Add specific properties onto your GeoJSON objects to specify which ones should not appear at certain zooms

But ultimately, there is a tradeoff. You can't have infinite information within every tile, so you will have to choose what information you do want to keep.

tippecanoe keeps dropping polygons at mid level zooms

1 Answers