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<DIV><SPAN class=955143513-21032008><FONT face=Arial size=2><SPAN
class=237194616-21032008>Hello,</SPAN></FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial size=2>I'm in charge of a
web application (InfoTerre) that shares french geological information. In the
current version, we use MapBuilder 1.0 on client side to request our WMS
servers, with some developments around that tool. One of those
customizations consists in switching the SRS at runtime with respect to the
location and the scale : for instance, the SRS is Lambert II if you are in
France but switches to WGS84 if you zoom out enough (if I am not clear, I let
you see it at </FONT><A title=http://infoterre.brgm.fr
href="http://infoterre.brgm.fr/"><FONT face=Arial
size=2>http://infoterre.brgm.fr</FONT></A><FONT face=Arial size=2>). Of course,
the WMS server has to be able to deal with both projections.
</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial size=2>Presently, for
performance issues, we are working on a new version that embeds MapBuilder 1.5
(based on OpenLayers) and that uses some raster layers as WMS-C (we use
TileCache). So far, our tests are promising since we can get the default raster
layer on France in Lambert II. However, TileCache does not take SRS into account
which is blocking for us. </FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial size=2>We are thinking of
implementing SRS switching in TileCache (we could generate independently, let's
say, 3 levels in EPSG4326 and 7 levels in EPSG27582, with potentialy level
overlaps and requests the same TileCache and the same layer in EPSG4326 and
EPSG27582). I do not know much about TileCache code architecture but I imagine
we could add a top level folder in the tile storage that specifies the SRS :
</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2>EPSG4326</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial size=2>
Level 01</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2> Tile001</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2> Tile002</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2> ...</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial size=2>
Level 02</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2> Tile001</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2> Tile002</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2> ...</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial size=2>
...</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2>EPSG27582</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008>
<DIV><SPAN class=955143513-21032008><FONT face=Arial size=2>
Level 01</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2> Tile001</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2> Tile002</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2> ...</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial size=2>
Level 02</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2> Tile001</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2> Tile002</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2> ...</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial size=2>
...</FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial size=2>Does it seem to you
reasonable or totaly crazy ? Moreover, would you have some advice on that
hazardeous project ;) ? </FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial><FONT size=2><SPAN
class=237194616-21032008>T</SPAN>hank you for any help you could provide.
</FONT></FONT></SPAN></DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=955143513-21032008><FONT face=Arial><FONT size=2><SPAN
class=237194616-21032008>R</SPAN>egards</FONT></FONT></SPAN></DIV></SPAN></DIV></SPAN><SPAN
class=955143513-21032008></SPAN></DIV></SPAN></DIV></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><SPAN class=237194616-21032008><FONT face=Arial
size=2>--</FONT></SPAN></DIV>
<DIV align=left>
<DIV dir=ltr align=left>
<DIV dir=ltr align=left><FONT face=Arial><FONT size=2>Anthony M<SPAN
class=237194616-21032008>auclerc</SPAN></FONT></FONT></DIV></DIV></DIV></BODY></HTML>