[OpenLayers-Users] Multiple projections in the same map

[Brad Spencer]

I do not understand this either. The whole concept of OGC's interoperability
supports the notion of a request to a WMS/WFS service as being projection
specific. The remote service is expected to do the conversion to the single
projection that the client application expects. Furthermore, if a remote
service does not support the projection requested a cascading WMS that
'points' to this downstream service but which does support the requested
projection can also do the transformation per request for the end user
client. The point is that a WMS service is expected to do the transformation
of the returned WMS maps. Transforming at the client application is not a
scalable approach to a true distributed Web solution.

Just my 2 cents worth.....

Brad


-----Original Message-----
From: users-bounces at openlayers.org [mailto:users-bounces at openlayers.org] On
Behalf Of Christopher Schmidt
Sent: Saturday, December 27, 2008 12:42 AM
To: Thomas Rokkjaer
Cc: users at openlayers.org
Subject: Re: [OpenLayers-Users] Multiple projections in the same map

On Fri, Dec 26, 2008 at 12:58:59AM -0800, Thomas Rokkjaer wrote:
> 
> Hi
> 
> I am not using OpenLayers anymore, since we developed our own webGIS.  
> I cannot remember what was the cause of the problem with using  
> multiple projections. However the use of map layers with different  
> projections is pretty straightforward. Sometimes you datasource comes  
> in different projections and you dont want the hassle of transforming  
> the maps.

But... you have to. Javascript can't transform images, so *something*
has to convert the images so that they're in the same projection, an
that can't be OpenLayers... There's not enough context hre for me to
really understand your question, but I can't understand a way in which
you can combine differently projected images in javascript.

-- Chris

> Med venlig hilsen
> Thomas Rokkjær
> Niras Informatik
> 30950774
> 
> Den 26/12/2008 kl. 05.06 skrev "Eric Lemoine (via Nabble)"
<ml-user+64477-1416789177 at n2.nabble.com 
>  >:
> 
> > On Jan 15, 2008 1:44 PM, Thomas Rokkjaer <thomas.rokkjaer at ...> wrote:
> > >
> > > Does a working example with layers with different projections in  
> > the same map
> > > exist?
> > > I am trying to create a simple demo page consisting of the basic WMS
> > > OpenLayers layer and a local projection layer from a GeoServer  
> > without
> > > success.
> >
> > You can override the map projection at the layer level. For that, just
> > set the projection option at layer creation time. In this way, you can
> > have layers with different projections.
> >
> > By the way, why would you want layers with different projections in
> > the same map?
> >
> > -- 
> > Eric
> > _______________________________________________
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> > Users at ...
> > http://openlayers.org/mailman/listinfo/users
> >
> >
> > This email is a reply to your post @
http://n2.nabble.com/Multiple-projections-in-the-same-map-tp1827057p1827058.
html
> > You can reply by email or by visting the link above.
> >
> 
> -- 
> View this message in context:
http://n2.nabble.com/Multiple-projections-in-the-same-map-tp1827057p1863520.
html
> Sent from the OpenLayers Users mailing list archive at Nabble.com.

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-- 
Christopher Schmidt
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