Forum: WebMapViewer Forum

"too estern" longitude value causes wrong polygon render

Geographical bounding polygon for some of our products occasionally crosses eastern hemisphere edge, so we get negative longitude values:

50.57,-179.55 56.85,138.30 35.02,137.39 30.57,167.04

When WMV tries to render such polygon it takes such "too eastern" longitude as "too western", so the polygon is being displayed incorrectly.

We have tried to apply some hack to the catalogue service output, increasing any negative longitude value by 360 degrees. This seems to work, yet EOLI states that longitude should be between -180..180. Should we continue to use the hack (we have disabled one by now) or it is possible to fix the issue on the level of WMV? Or may be the portal itself? Could you please give any ideas on how to do this in appropriate way?

Best regards, Ilya

Re: "too estern" longitude value causes wrong polygon render

Dear Ilya,

There is a special switch in the WebMapViewer that allows handling dateline crossing polygons. In tab 10 of the WebMapViewer configurator , you will find a dateline correction option. Set this to EO Product Footprint and dateline crossing polygons should be properly displayed. There is a limitation in the algorithm for very complex polar crossing footprints but it should work for the footprints shown in your example.

Best regards,


Re: Re: "too estern" longitude value causes wrong polygon render

Dear Steven!

I just got my catalogue fixed using your recommendation. The option name wasn't too obvious for me, so I just didn't pay attention to one playing with settings earlier.
Thank your for you help.

Best regards, Ilya

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