Hello Jani, I was coming across a very similar problem to yours. I needed to represent networks that spanned the IDL, with points and lines. ( http://www.sourcemap.org/beta/stage/index.php/objects/object-105) The way that I got around the wrapping was to add points and lines as multi-point and multi-line geometry collections. 1 geometry would lie within the bounds of the coordinate system (-180 to 180, in your case below), and the other geometries would be -x and +x * 360. For example, mapping 0, 51.47722 (Greenwich, UK), would place points at -360, 0, and 360. One could extend this as many times as necessary, based on the aspect and maxExtent of the map.
This approach adds a bunch of features to the map, but gets rid of the flipping when the map is scrolled over the IDL. David On Mon, Jun 29, 2009 at 5:41 AM, Jani Patokallio <[email protected]> wrote: > Greetings, > > I have an OpenLayers app (http://openflights.org) with maps that are > scaled according to the user's screen resolution and, when zoomed out, > span the entire globe (maxExtent -180,-90.0,180.0,90.0). Based on my > experimentation, it appears that... > > If I specify "maxResolution: auto": > + the map is scaled correctly according to the user's screen size, with > the whole world displayed by default > - random gaps appear at the dateline, depending on the user's screen size > > If I specify "maxResolution: 0.3515625" (*) > + there is never any dateline gap > + the map is scaled correctly on a 1024x768 display > - only a portion of the world is visible at 800x600 > > So am I really forced to make a choice between one and the other? For > reference: > > var mapOptions = { > maxResolution: 0.3515625, > restrictedExtent: new OpenLayers.Bounds(-9999, -90, 9999, 90), > maxExtent: new OpenLayers.Bounds(-180,-90.0,180.0,90.0), > numZoomLevels: 8, > }; > > (*) derived experimentally from the sequence in > http://trac.openlayers.org/wiki/SettingZoomLevels. > > Cheers, > -jani > > > > > _______________________________________________ > Users mailing list > [email protected] > http://openlayers.org/mailman/listinfo/users >
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