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pnorman / spirit

Creative Commons Zero v1.0 Universal
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Geometry simplification #41

Open westnordost opened 2 weeks ago

westnordost commented 2 weeks ago

Background: I would love to use the upcoming openstreetmap-hosted vector tiles for StreetComplete, to have the app only communicate with OpenStreetMap / FOSS services. However, especially because it is a mobile app, I want to keep the bandwidth requirements low.

As I noted earlier, tilekiln tiles are about 10x as big as the tiles from a commercial provider serving OSM-based vector tiles*.

I suspect that most of the difference in size is due to (missing) geometry simplification on low to mid zoom levels.

Is this done at all, or already done to a degree exceeding rounding to the max precision available per zoom level? I can understand that the requirement for minutely updates might run contrary to employing costly simplification.

* that provider is known for very small tiles though, so not completely fair comparison. Compared with maptiler, tilekiln is "only" about 3x the size, currently.

pnorman commented 1 week ago

Moved from tilekiln because this is a spirit specific issue - tilekiln just generates what the style says.

westnordost commented 1 week ago

And does the style currently do any geometry simplification?