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My question is connected with QGIS 2. Could anybody explain me how I ought to reproject the Natural Earth dataset there in order my world map to look correctly? When I strive to reproject these data I get the result that you can see on the image below.

I was using the next parameters for my projection:

+proj=eck1 +lon_0=120 +x_0=0 +y_0=0 +ellps=WGS84 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs

That is a modified "World Eckert I" projection.

Figure 1. Natural Earth dataset after reprojecting

AndreJ
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Eugene Kluichnikov
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  • Looks like your vertices cross the +/- 180 degree meridians - related http://gis.stackexchange.com/questions/41827/how-to-build-a-minimum-convex-hull-crossing-the-180-degrees-line – Mapperz Oct 30 '13 at 15:56
  • @Mapperz: Not the 180° degree, but 60°W as the antipodial meridian to the chosen projection causes the error. – AndreJ Oct 31 '13 at 06:53

1 Answers1

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You have to split up your world at 60° West (or better between -60.1° and -59.9° East) to avoid those artefacts of polygon filling, if you center at 120° East.

  • Change project CRS to EPSG:4326

  • Create a text file with the following content:

 Nr;WKT
 1;POLYGON((-60.1 100, -59.9 100, -59.9 -100, -60.1 -100, -60.1 100))

  • Import it as delimited text with semicolon as delimiter and EPSG:4326 as CRS

  • Perform Vector -> Geoprocessing -> Difference on the ne_10m_land to a new shapefile

  • Remove the ne_10m_land and the polygon around -60° layers from the canvas

  • change project CRS to Eckert I

And your map will look like this:

enter image description here

AndreJ
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