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mapzen / metro-extracts

DEPRECATED. See readme for alternative ways to get "city-sized chunks" of OpenStreetMap data
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Lake Michigan incorrectly clipped in Chicago extract #298

Open potash opened 7 years ago

potash commented 7 years ago

In the Chicago extract the Lake Michigan polygon (osm id 1205149) is clipped to something very small and incorrect.

potash commented 7 years ago

Could this be related to the fact that Lake Michigan (and the other Great Lakes) are not tagged as with natural=coastline? Or are there clipping issues like this for all waterbodies in the metro extracts?

rmglennon commented 7 years ago

This also came in to Mapzen support (see Desk 1051). A user sent a Chicago coastline shapefile that was downloaded in October 2015 that has coast and land shapes that were as expected.

This is a problem with any extracts that include Lake Michigan. For example, Milwaukee returns an empty coastline and a large land polygon there, too.

I tested with Tampa and a few custom extracts along the coast, and they were as expected. It appears that something upstream is not happy with the Lake Michigan relation edits.

nvkelso commented 7 years ago

Often times when water goes missing it's newly moved to the OSM water layer that's a separate data download off Metro Extracts. I haven't confirmed in your case, but check for it there. The same thing has been happening in vector tiles along the Gulf coast (see Texas).

potash commented 7 years ago

@nvkelso thanks for pointing out the water layer. However, in the case of Chicago the water layer appears empty:

$ ogrinfo chicago_illinois_water_coast.shp chicago_illinois_water_coast
INFO: Open of `chicago_illinois_water_coast.shp'
      using driver `ESRI Shapefile' successful.

Layer name: chicago_illinois_water_coast
Geometry: Polygon
Feature Count: 0
Extent: (0.000000, 0.000000) - (0.000000, 0.000000)
Layer SRS WKT:
GEOGCS["GCS_WGS_1984",
    DATUM["WGS_1984",
        SPHEROID["WGS_84",6378137,298.257223563]],
    PRIMEM["Greenwich",0],
    UNIT["Degree",0.017453292519943295]]
FID: Integer64 (11.0)
rmglennon commented 7 years ago

In this case, to clarify, the Water > Coastlines shapefile is empty (0 features) and the Coastlines > Land shapefile has one feature in it that is a large bounding box, possibly the size of the whole lake.

These layers were populated in the past (per the 2015 example sent through support).

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