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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I considered the very same issue and opted for a pragmatic solution. Here’s my internal notes on this:<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal style='margin-left:.5in'>This approach seems consistent with what Frank W <a href="http://trac.osgeo.org/gdal/ticket/3962">proposed</a>:<o:p></o:p></p><p class=MsoNormal style='margin-left:1.0in'>“<span style='font-size:10.0pt;font-family:"Verdana","sans-serif";color:black;background:#FFFFDD'>I am thinking that we should move to treating the pseudo-mercator projection method better in WKT, and tying the various systems together properly. Either use a custom projection like ESRI ("Mercator_Auxiliary_Sphere") or introduce the "Auxilary_Sphere_Type" parameter to standard Mercator.</span><o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'>I’ll note that some of the names are different than what <a href="http://www.epsg-registry.org/report.htm?type=selection&entity=urn:ogc:def:crs:EPSG::3857&reportDetail=long&title=&reportDetail=long&style=urn:uuid:report-style:default-with-code&style_name=OGP%20Default%20With%20Code&title=">EPSG-registry.org has to say about all this</a>. <o:p></o:p></p><p class=MsoListParagraphCxSpFirst style='margin-left:1.0in;mso-add-space:auto;text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>I’d like to see ESRI recognize a Projection Name of “Pseudo_Mercator” and for GDAL to use this string instead of “Mercator_Auxiliary_Sphere” since that’s the alias used by EPSG. OTOH, if we leave it as Mercator_Auxiliary_Sphere, then our fix would work for older versions of ArcGIS… <o:p></o:p></p><p class=MsoListParagraphCxSpLast style='margin-left:1.0in;mso-add-space:auto;text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>That the parameters are “central_meridian” and “standard_parallel_1” instead of “Latitude/Longitude of Natural Origin” seems wrong but that happens a lot comparing other GDAL/EPSG transforms. For example we have exactly this mismatch with the Mercator_1SP projection method used by WGS84 / World Mercator (3395). I think it would be ill-advised to push to change this.<o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> gdal-dev-bounces@lists.osgeo.org [mailto:gdal-dev-bounces@lists.osgeo.org] <b>On Behalf Of </b>Stefano Iacovella<br><b>Sent:</b> Thursday, August 29, 2013 2:22 PM<br><b>To:</b> Even Rouault<br><b>Cc:</b> gdal-dev<br><b>Subject:</b> Re: [gdal-dev] Patch for GDAL Web Mercator Issue / trac 3962<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>2013/8/29 Even Rouault <<a href="mailto:even.rouault@mines-paris.org" target="_blank">even.rouault@mines-paris.org</a>><o:p></o:p></p><div id=":8c"><p class=MsoNormal>Well this is the name of the projected coordinate system. But here we are<br>talking more about the projection method (sorry for being pedantic...). The<br>EPSG registry would suggest "Popular Visualisation Pseudo-Mercator" for it.<o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'>On the contrary, thank you for letting me understand better and sorry for the noise :)<o:p></o:p></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'>Kind Regards,<o:p></o:p></p></div><div><p class=MsoNormal>Stefano<o:p></o:p></p></div><div><p class=MsoNormal><br clear=all><o:p></o:p></p><div><p class=MsoNormal>---------------------------------------------------<br>41.95581N 12.52854E<br><br><br><a href="http://www.linkedin.com/in/stefanoiacovella" target="_blank">http://www.linkedin.com/in/stefanoiacovella</a><br><br><a href="http://twitter.com/#!/Iacovellas" target="_blank">http://twitter.com/#!/Iacovellas</a><o:p></o:p></p></div></div></div></div></body></html>