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I am working with this natural earth shapefile. The dateline disappears after using the mentioned clip to hemisphere plugin. Densifying the geometry does not help.

Weird to me seems that clipping to a hemisphere centered at lat -76,98267 / lon -163,36119 works just fine (dateline present after clip) while after clipping to a center at lat 26,50588 / lon -171,82873 the dateline dissaperes although it should be visible.

Solved as noticed in the comments by @Jake a bug in the clip to hemisphere plugin is the problem. I quickfixed it and its all good now.

PolyGeo
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simooooon
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  • Possibly try densifying the geometries. – mkennedy Nov 30 '16 at 00:30
  • If the reported failed values are in radians, they're either approximately 30, -13.5 or the reverse (not sure which is latitude). It's probably lat=-13.5 lon=30, which is very, very close to the "horizon"/hemisphere edge. (This assumes center is -77, -163). – mkennedy Nov 30 '16 at 03:39
  • @AndreJ: Using decimal points instead of commas fixed the problem when I tried to reproduce the error. Note that removing the features from the rear of the view is what the ClipToHemisphere-Plugin does (which simooooon used in step 1). – Jake Dec 01 '16 at 11:57
  • @simooooon: Does densifying the geometry (using Vector / Geometry Tools / Densify Geometries) as suggested by mkennedy solve the problem with the disappearing dateline? If not, could you edit your question to describe the problem in more detail? – Jake Dec 01 '16 at 12:00
  • For the dateline issue, you might take a look at http://gis.stackexchange.com/questions/165290/how-to-re-project-a-netcdf-file/165293#165293 – AndreJ Dec 01 '16 at 13:00
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    This is a bug in the Clip to Hemisphere plugin (I've opened a ticket). As a quick fix, you can change the 180 in https://github.com/jdugge/ClipToHemisphere/blob/master/ClipToHemisphere.py#L264 to 180.1 in your local copy of the plugin (in .qgis2\python\plugins\ClipToHemisphere in your home directory), then restart QGIS. I'll fix the error and upload a new version of the plugin on the weekend. – Jake Dec 01 '16 at 16:45
  • Have you tried the Vector > Data Management > Define Current Projection tool? There is also a "Reproject Layer" tool in the Processing toolbox. – GIS_Canuck Nov 29 '16 at 16:49
  • This is now fixed and the corrected version of the plugin is available in the QGIS plugin repository. – Jake Dec 03 '16 at 10:37

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