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I have this weird render everytime I process world data in software like FME, QGIS and ArcGIS. I noticed these rectangles crossing the world are related to lands areas between -180 and 180 longitudes. Does anyone know what is the reason of this and how to avoid it?enter image description here

Edited: I noticed that this happen only when FME creates the polygons. If ArcGIS creates it, the rendering is correct in ArcGIS.

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    The classic data stretch when data goes beyond the 180 meridians. You will need to clip or use a different projection to eliminate this.
    – Mapperz
    Commented Feb 14, 2017 at 17:21

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You are "processing" the data in FME, QGIS and ArcGIS - but how are you viewing the data? For example, the FME Data Inspector will show the data correctly, but only until you turn on a background map, when it will appear as above. So what application is the above screenshot from?

Also, the format is going to be important I think. For example, if you have Google KML datasets, then FME would write data correctly, eg:

<coordinates>175.0,-10.0,0.0 175.0,10.0,0.0 -175.0,10.0,0.0 -175.0,-10.0,0.0 175.0,-10.0,0.0</coordinates>

...but Google Earth won't show the data correctly. However, if you wrote the data as:

<coordinates>-185.0,-10.0,0.0 -185.0,10.0,0.0 -175.0,10.0,0.0 -175.0,-10.0,0.0 -185.0,-10.0,0.0</coordinates>

...then Google Earth is more than happy to show that feature!

So I think it's a combination of coordinate system (as @MappaGnosis says), how well the data format supports this (and how are you creating it), plus whether the application you are using is actually capable of interpreting and rendering this properly at all.

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    Coincidentally, this question (in relation to FME) was also asked on the FME Knowledge Center Q+A board today: knowledge.safe.com/questions/39941/… Commented Feb 14, 2017 at 16:10
  • I was reading and processing the data in FME. The same dataset processed in ArcMAP is totally correct, I mean the rendering (EPSG : 3857)
    – Camilo
    Commented Mar 16, 2017 at 17:09
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It is a projections thing. Your data are most likely in EPSG:4326 (WGS84) and you are displaying it in EPSG:3857 (possibly vice versa) and reprojecting on the fly. Try reprojecting the data to the same SRS as your view (or change the view).

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  • It is EPSG : 3857. FME generates the wrong rendering of polygons. ArcGIS is porocessing and displaying the data correctly.
    – Camilo
    Commented Mar 16, 2017 at 17:13

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