<div dir="ltr"><div>Arnd, Sergant_york<br><br>Thats actually quite scary on one hand, but thanks a lot for clarifying it for me! <br><br></div>Casper<br></div><div class="gmail_extra"><br><br><div class="gmail_quote">On Thu, Jan 17, 2013 at 7:46 PM, Arnd Wippermann <span dir="ltr"><<a href="mailto:arnd.wippermann@web.de" target="_blank">arnd.wippermann@web.de</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><u></u>
<div>
<div dir="ltr" align="left"><span><font color="#0000ff" face="Arial">Hi Caspar,</font></span></div><div class="im">
<div dir="ltr" align="left"><span><font color="#0000ff" face="Arial"></font></span> </div>
<div dir="ltr" align="left"><span>"</span>If the layer
projection equals the mapprojection, the layer projection is returned<span>"</span></div>
<div dir="ltr" align="left"><span><font color="#0000ff" face="Arial"></font></span> </div>
</div><div><span><font color="#0000ff" face="Arial">In the
case of map projection = EPSG:900913 and a WMS projection =
EPSG:3857 the WMS GetMap Request will use EPSG:3857.</font></span></div>
<div><span></span><span></span><font face="Arial"><font color="#0000ff"><font>B<span>ecause EPSG:900913 equals EPSG:3857.
Declared in Projection.js.</span></font></font></font></div>
<div><font face="Arial"><font color="#0000ff"><font><span></span></font></font></font> </div><span>
<div><font color="#0000ff" face="Arial"><span>For
other projections and aliases OpenLayers cann't decide equality and the map
projection will be used.</span></font></div>
<div><font color="#0000ff" face="Arial"></font> </div>
<div><font face="Arial"><font color="#0000ff"><font><span>I</span>f you include the proj4js-library to your
application, then OpenLayers tests for equality by text comparision of
the proj-strings and that may lead to other results as above, if the <span>proj-</span>strings not ===.<span> </span></font></font></font></div>
<div><font face="Arial"><font color="#0000ff"><font><span>But it would also provide a possibility to add other
projections and aliases to ones
applications.</span></font></font></font></div></span></div>
<div><font face="Arial"><font color="#0000ff"><font><span></span></font></font></font><font face="Arial"><font color="#0000ff"><font><span></span></font></font></font><font color="#0000ff" face="Arial"></font> </div>
<div><span></span><font face="Arial"><font color="#0000ff"><font>A<span>rnd</span></font></font></font><br></div>
<div dir="ltr" align="left" lang="de">
<hr>
<font face="Tahoma"><b>Von:</b> Casper Span
[mailto:<a href="mailto:info@spatially-oriented.com" target="_blank">info@spatially-oriented.com</a>] <br><b>Gesendet:</b> Donnerstag, 17. Januar
2013 08:51<br><b>An:</b> <a href="mailto:arnd.wippermann@web.de" target="_blank">arnd.wippermann@web.de</a><div><div class="h5"><br><b>Cc:</b>
<a href="mailto:openlayers-users@lists.osgeo.org" target="_blank">openlayers-users@lists.osgeo.org</a><br><b>Betreff:</b> Re: [OpenLayers-Users]
epsg:3857 and google 900913<br></div></div></font><br></div><div class="HOEnZb"><div class="h5">
<div></div>
<div dir="ltr">
<div>
<div>
<div>Arnd,<br><br>I'm talking about lines 247-251 from wms.js (<a href="https://github.com/openlayers/openlayers/blob/master/lib/OpenLayers/Layer/WMS.js" target="_blank">https://github.com/openlayers/openlayers/blob/master/lib/OpenLayers/Layer/WMS.js</a>):<br>
<br>var
mapProjection = this.map.getProjectionObject();<br>var projectionCode =
this.projection && this.projection.equals(mapProjection) ?
this.projection.getCode() : mapProjection.getCode();<br>var value =
(projectionCode == "none") ? null : projectionCode;<br><br></div>If the layer
projection equals the mapprojection, the layer projection is returned. If not,
the mapprojection is returned.<br><br></div>Correct me if I'm wrong, but that
would say it always returns the map projection code, no matter what I fill in on
the projection code or when I fill it.<br><br></div>
<div>I came across this piece of code after building a WMS server with SharpMap.
I only built in support for EPSG:3857 but the default OSM layer is in
EPSG:900913. My WMS server kept coming with error "SRS 900913 not
supported"<br></div>
<div>Please note that in my case the WMS layer is NOT my base layer. If it was,
it WOULD listen to the projection of the layer (as the Map.Projection asks it's
baselayer for the projection)<br></div>
<div><br></div>Casper<br></div>
<div class="gmail_extra"><br><br>
<div class="gmail_quote">On Wed, Jan 16, 2013 at 11:13 PM, Arnd Wippermann <span dir="ltr"><<a href="mailto:arnd.wippermann@web.de" target="_blank">arnd.wippermann@web.de</a>></span> wrote:<br>
<blockquote style="BORDER-LEFT:#ccc 1px solid;MARGIN:0px 0px 0px 0.8ex;PADDING-LEFT:1ex" class="gmail_quote"><u></u>
<div>
<div dir="ltr" align="left"><span><font color="#0000ff" face="Arial">Hi
Caspar,</font></span></div>
<div>
<div dir="ltr" align="left"><span><font color="#0000ff" face="Arial"></font></span> </div>
<div dir="ltr" align="left"><span>"</span>In other words, it will only use the map
projection in it's WMS request URL's<span>"</span></div>
<div><span></span> </div></div>
<div><span><font color="#0000ff" face="Arial">That's not right as you have found
out by yourself. If the map projection is equal the wms projection, then the
WMS GetMap Request use the wms projection.</font></span></div>
<div><font color="#0000ff" face="Arial"></font> </div>
<div><span></span><font face="Arial"><font color="#0000ff"><font size="+0">S<span>ome servers provide only requests for EPSG:3857 (an alias for
EPSG:900913) and if you use for your map EPSG:900913, then you can add these
servers and set the projection to EPSG:3857 and it
works.</span></font></font></font></div>
<div><font face="Arial"><font color="#0000ff"><font size="+0"><span></span></font></font></font> </div>
<div><font face="Arial"><font color="#0000ff"><font size="+0"><span>But it seems,
that that only works for EPSG:900913 and EPSG:4326 and their aliases, because
OpenLayers has aliases defined in OpenLayers
Projection.js.</span></font></font></font></div>
<div><font face="Arial"><font color="#0000ff"><font size="+0"><span></span></font></font></font> </div>
<div><font face="Arial"><font color="#0000ff"><font size="+0"><span>If you have maps
with other projections and a server support only an alias of the projection,
then the above will perhaps not work.</span></font></font></font></div>
<div><font face="Arial"><font color="#0000ff"><font size="+0"><span></span></font></font></font> </div>
<div><font face="Arial"><font color="#0000ff"><font size="+0"><span>Then the only
way is to overwrite the getFullRequestString-method of
OpenLayers.Layer.WMS.</span></font></font></font></div>
<div><font face="Arial"><font color="#0000ff"><font size="+0"><span></span></font></font></font> </div>
<div><font face="Arial"><font color="#0000ff"><font size="+0"><span>Example</span></font></font></font></div>
<div><font face="Arial"><font color="#0000ff"><font size="+0"><span><a href="http://gis.ibbeck.de/ginfo/apps/OLExamples/OL212/wms_options_projection.asp" target="_blank">http://gis.ibbeck.de/ginfo/apps/OLExamples/OL212/wms_options_projection.asp</a></span></font></font></font></div>
<div><font face="Arial"><font color="#0000ff"><font size="+0"><span></span></font></font></font> </div>
<div><font face="Arial"><font color="#0000ff"><font size="+0"><span>Arnd</span></font></font></font></div>
<div><br></div><br>
<div dir="ltr" align="left" lang="de">
<hr>
<font face="Tahoma"><b>Von:</b> <a href="mailto:openlayers-users-bounces@lists.osgeo.org" target="_blank">openlayers-users-bounces@lists.osgeo.org</a> [mailto:<a href="mailto:openlayers-users-bounces@lists.osgeo.org" target="_blank">openlayers-users-bounces@lists.osgeo.org</a>] <b>Im Auftrag von
</b>Casper Span<br><b>Gesendet:</b> Mittwoch, 16. Januar 2013
12:53<br><b>An:</b> Sergeant_york<br><b>Cc:</b> <a href="mailto:openlayers-users@lists.osgeo.org" target="_blank">openlayers-users@lists.osgeo.org</a><br><b>Betreff:</b> Re:
[OpenLayers-Users] epsg:3857 and google 900913<br></font><br></div>
<div>
<div>
<div></div>
<div dir="ltr">
<div>
<div>
<div>
<div>
<div>
<div>Hi,<br><br></div>If you look at the source of WMS
(lib\OpenLayers\Layer\WMS.js), take a look at
getFullRequestString.<br></div>In it, the baselayer's projection will always
override the given projection. In fact, the layers projection itself will be
ignored:<br></div>- It takes the Map Projection (=Baselayer
projection)<br></div>- then, if the WMS layer projection equals the map
projection, it uses the layer projection<br></div>- otherwise, it uses the map
projection<br><br></div>In other words, it will only use the map projection in
it's WMS request URL's<br>
<div>
<div>
<div>
<div><br>So yeah... everything MUST be the same projection for WMS layers or
it cannot be placed on top of eachother.<br>
<div class="gmail_extra"></div>
<div class="gmail_extra">For me, this meant reprojecting my own data so I can
serve it with WMS onto OSM.<br><br></div>
<div class="gmail_extra">You can check these actual outgoing URL's with Firebug
and such.<br><br></div>
<div class="gmail_extra">regards,<br></div>
<div class="gmail_extra">Casper Span<br></div>
<div class="gmail_extra"><br>
<div class="gmail_quote">On Wed, Jan 16, 2013 at 12:31 PM, Sergeant_york <span dir="ltr"><<a href="mailto:electronicpanda@gmail.com" target="_blank">electronicpanda@gmail.com</a>></span> wrote:<br>
<blockquote style="BORDER-LEFT:#ccc 1px solid;MARGIN:0px 0px 0px 0.8ex;PADDING-LEFT:1ex" class="gmail_quote">Hello there,<br><br>Thank you for the answer. That gave me
a good idea. Unfortunately it doesn't<br>work when initializing
layer.<br><br>On the other hand creating a layer (for example aLayer object)
then changing<br>projection works!<br><br>Workin way is:<br>layer aLayer=new
OpenLayers.Layer.WMS ......<br>aLayer.projection= new
OpenLayers.Projection("EPSG:3857")<br><br><br><br>--<br>View this message in
context: <a href="http://osgeo-org.1560.n6.nabble.com/epsg-3857-and-google-900913-tp5027619p5027809.html" target="_blank">http://osgeo-org.1560.n6.nabble.com/epsg-3857-and-google-900913-tp5027619p5027809.html</a><br>
<div>
<div>Sent from the OpenLayers Users mailing list archive at
Nabble.com.<br>_______________________________________________<br>Users
mailing list<br><a href="mailto:Users@lists.osgeo.org" target="_blank">Users@lists.osgeo.org</a><br><a href="http://lists.osgeo.org/mailman/listinfo/openlayers-users" target="_blank">http://lists.osgeo.org/mailman/listinfo/openlayers-users</a><br>
</div></div></blockquote></div><br><br clear="all"><br>-- <br><br>Casper Span<br>T: <a href="https://twitter.com/#%21/Span_Droid" target="_blank">@Span_Droid</a><br>W:
<a href="http://www.spatially-oriented.com" target="_blank">http://www.spatially-oriented.com</a><br>M: <a href="mailto:info@spatially-oriented.com" target="_blank">info@spatially-oriented.com</a><br><br></div></div></div>
</div></div></div></div></div></div></blockquote></div><br><br clear="all"><br>-- <br><br>Casper Span<br>T: <a href="https://twitter.com/#%21/Span_Droid" target="_blank">@Span_Droid</a><br>W:
<a href="http://www.spatially-oriented.com" target="_blank">http://www.spatially-oriented.com</a><br>M: <a href="mailto:info@spatially-oriented.com" target="_blank">info@spatially-oriented.com</a><br><br></div>
</div></div></blockquote></div><br><br clear="all"><br>-- <br><br>Casper Span<br>T: <a href="https://twitter.com/#%21/Span_Droid" target="_blank">@Span_Droid</a><br>W: <a href="http://www.spatially-oriented.com" target="_blank">http://www.spatially-oriented.com</a><br>
M: <a href="mailto:info@spatially-oriented.com" target="_blank">info@spatially-oriented.com</a><br><br>
</div>