Describe the process

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  • updated
  • Under review

It would be very nice if you could explain how you do the data processing.

Thank you for offering this great tool.

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Magnus
  • Under review

Since the site is still in early development we haven't gotten that far yet. The site has existed for almost a year, but since it's a side-project we don't spend too much time on it, therefore we still see it as a young, and a bit immature, project.

Basically the import of data is a combination of these tools:

* PostgreSQL/PostGIS

* osm2pgsql

* osmcoastline

* ogr2ogr

The tree itself is built calculated from overlaps.

If you have more specific questions you are welcome to ask them.

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james

thank you for sharing.

after loading osm into the database: how long does it take to compute the overlaps?

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Magnus

That step has an ETA of 2-3 hours according to the code. Could be that some other things is done as well in the same routine.

What takes the longest time is to create the land-only-polygons, roughly two weeks. The goal is to be able to set databases live before they have those calculated, but the code does not yet support the fact that they don't exist.

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james
1. which are the land-only polygons? all polygons that are finally displayed on the boundaries map?

2. which tool does the polygon creation?

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Magnus

Question 1 is answered on the site.

"By selecting the option Land only you will download polygons we have prepared to follow the coast line instead, these are often a lot more complex and might use a lot of resources."

Question 2 - osm2pgsql. It combines the data in OSM (ways, nodes and relations) into polygons.