[OpenLayers-Users] problem w/ WMS Layer using wrapDateLine and displaying a feature which crosses the dateline

[Matthew Doyle]

Hello John,

I don't have an easy solution for you, but i'd like to point out that i was
also having great difficulty with this some months ago. So much so, that i
ended up reprojecting my entire map 90 degrees to the west (essentially
moving the real dateline) so that nothing crossed the OpenLayers boundary
and hence avoided using the wrapDateLine=true option. This has proved to be
a pain since any new data needs to be manually shifted, not to mention the
on-the-fly calculations i need to do for all vector points and longitude
numbers which are user-facing.

A simple search of this usergroup will suggest that support for maps that
wrap at the international dateline is quite poor. A lot of other users have
had difficulty with this too, especially when using vectors which cross the
line or appear either side of the line - causing them to either fail, or
display only on one side at a time.

I'd be interested to know if there is any scope for further development in
improving the support for maps (WMS/WFS/Vector) which need to cross the
international dateline.  I feel this is the only agenda left which is
leaving OpenLayers lagging behind it's rival tools.

Best regards,
Matt


John Cartwright-2 wrote:
> 
> sorry - forgot to mention this is happening on version 2.8, but I  
> think I also saw the same problem at 2.7.
> 
> --john
> 
> 
> On Jul 14, 2009, at 12:00 AM, John Cartwright wrote:
> 
>> Hello All,
>>
>> I'm experiencing some strange behavior using a Layer defined like:
>>
>> var wms = new OpenLayers.Layer.WMS( "OpenLayers WMS",
>>                 "http://labs.metacarta.com/wms/vmap0?", {layers:  
>> 'basic'}, {wrapDateLine:true});
>>
>> and then adding a WKT feature to it defined like:
>>
>> MULTILINESTRING((150 0, 180 0), (-180 0, -150 0))
>>
>>
>> It initially displays properly, but when one pans in the x  
>> direction, the feature does not redraw correctly.  This seems to  
>> only be a problem when using the wrapDateLine option.
>>
>>
>> Is this a known issue or am I missing something?
>>
>> Thanks!
>>
>> --john
>>
>>
>> _______________________________________________
>> Users mailing list
>> Users at openlayers.org
>> http://openlayers.org/mailman/listinfo/users
> 
> 
> _______________________________________________
> Users mailing list
> Users at openlayers.org
> http://openlayers.org/mailman/listinfo/users
> 
> 

-- 
View this message in context: http://n2.nabble.com/problem-w--WMS-Layer-using-wrapDateLine-and-displaying-a-feature-which-crosses-the-dateline-tp3255732p3266679.html
Sent from the OpenLayers Users mailing list archive at Nabble.com.