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<font face="Lucida Grande" size="3">The 180 problem.</font> </p>
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<font face="Lucida Grande" size="3">Based in New Zealand we constantly want to draw a polygon to select search areas that cross the anti-meridian. While I have managed to fake areas that cross that line by using invalid coordinates such as 190E the polygon then disappears when the center of the map crosses to the other side of the line. To combat that I make two copies of the original polygon, one in the world to the east (+= 360 on every point) and one to the west (-= 360 on every point). That solves rendering a known polygon, but when the user is clicking on the map to define their own area they can't cross the anti-meridian without their line going around the long way.</font> </p>
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<font face="Lucida Grande" size="3">~Craig</font> </p>
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>>> Marc Jansen <jansen@terrestris.de> 8/5/2011 7:26 PM >>><br>Hi all,<br><br>for my talk "Common pitfalls for users of OpenLayers" [1] at this years<br>FOSS4G [2] I want to evaluate the parts of OpenLayers where users of the<br>library experience problems.<br><br>You would help me -- and the project itself -- a lot if you could answer<br>in this thread and tell me what problems you had working with OpenLayers.<br><br>Please do not hesitate to tell us what has bugged you, what was unclear<br>or non-intuitive. Provide us with the sall and the big annoyances Of<br>course you are heavily encouraged to provide ways around the pitfalls<br>and possible enhancements.<br><br>I want to identify areas which often cause problems... and eventually I<br>plan on making the library better where this is possible.<br><br>Anyone is invited to share his/her thoughts -- so if you want the<br>library to improve, go on and tell us where we can make things better.<br><br>Thanks in advance,<br>Marc<br><br><br>[1] <a href="http://2011.foss4g.org/sessions/common-pitfalls-users-openlayers">http://2011.foss4g.org/sessions/common-pitfalls-users-openlayers</a><br>[2] <a href="http://2011.foss4g.org/">http://2011.foss4g.org/</a><br>_______________________________________________<br>Users mailing list<br>Users@lists.osgeo.org<br><a href="http://lists.osgeo.org/mailman/listinfo/openlayers-users">http://lists.osgeo.org/mailman/listinfo/openlayers-users</a><br>
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