Opened 10 years ago

Closed 5 years ago

#1647 closed defect (invalid)

lake crossing 180th meridian drawn the long way round

Reported by: robx Owned by: jburgess777@…
Priority: major Milestone:
Component: mapnik Version:
Keywords: Cc: mapnik-team@…

Description

I've mapped a lake that crosses the 180th meridian: http://openstreetmap.org/browse/way/31254026 or http://openstreetmap.org/?lat=65.86427&lon=-179.99315&zoom=15&layers=B000FTT . This should be valid data, describing a lake in that area of the world. However, the mapnik slippy map rendering draws the lake all across the world, see eg http://www.openstreetmap.org/?lat=65.8642&lon=24.1557&zoom=12&layers=B000FTF

I'm not sure if this is in osm2pgsql or mapnik.

There's some other rendering oddities near the 180th meridian, but those may have to do with the fact that coastline doesn't actually connect there, and I've hesitated to join it up.

See also http://wiki.openstreetmap.org/wiki/180th_meridian

Cheers Robert

Change History (2)

comment:1 Changed 10 years ago by Ldp

Cc: mapnik-team@… added
Owner: changed from steve8@… to jburgess777@…

As #1612 and #1613 also show, this is a difficult problem to attack. Osmarender doesn't do any better here, either.

Perhaps osm2pgsql should take it upon itself to create 2 objects for dateline crossing features, but that's not my call. Handing this one over to Jon.

comment:2 Changed 5 years ago by pnorman

Resolution: invalid
Status: newclosed

Not an openstreetmap.xml or openstreetmap-carto issue. It could be an osm2pgsql issue, except there's no dateline crossing features the way OSM data is defined (WGS84).

A line going from (179.99,0) to (-179.99,0) is a 40,075 km line along the equator (https://trac.openstreetmap.org/ticket/1612#comment:11)

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