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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hi all,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’m running into problems using Proj4js to transform coordinates between ESPG:900916 (“web Mercator”) and EPSG:26986 (Massachusetts mainland state plane NAD83, meters) and vice-versa. The results I’m getting are way off.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’ve constructed a minimal test case that illustrates the problem:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><b>[ BEGIN CODE]<o:p></o:p></b></p><p class=MsoNormal>function initialize() { <o:p></o:p></p><p class=MsoNormal> Proj4js.reportError = function(msg) { alert('Proj4 error: ' + msg); } ;<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal> // Massachusetts State Plane NAD83, meters<o:p></o:p></p><p class=MsoNormal> var oDestPrj = new Proj4js.Proj('EPSG:26986');<o:p></o:p></p><p class=MsoNormal> // Google "web mercator"<o:p></o:p></p><p class=MsoNormal> var oSrcPrj = new Proj4js.Proj('EPSG:900913'); <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal> // A point location in web mercator.<o:p></o:p></p><p class=MsoNormal> var myPoint = { x: -73.21132, y: 42.71387 };<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal> // Project my point to EPSG:26986.<o:p></o:p></p><p class=MsoNormal> Proj4js.transform(oSrcPrj, oDestPrj, myPoint);<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal> // Result should be (approximately) 59819.70, 941765.22<o:p></o:p></p><p class=MsoNormal> document.write("x : " + myPoint.x + " y : " + myPoint.y);<o:p></o:p></p><p class=MsoNormal>}<o:p></o:p></p><p class=MsoNormal><b>[ END CODE]<o:p></o:p></b></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>In the example above, the input point { x: -73.21132, y: 42.71387 } is transformed into { x : 9220379.520106662 y : -186260.82310388796 }.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’m using a newly downloaded copy of Proj4js 1.1.0, the SRS definition for EPSG:900913 that came with the Proj4js download, and the SRS definition for EPSG:26986 downloaded from <a href="http://www.spatialreference.org">www.spatialreference.org</a>.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’ve either stumbled upon a bug, or am doing something incredibly bone-headed. <o:p></o:p></p><p class=MsoNormal>Any help that might be offered would be much appreciated.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks,<br>Ben<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><b><span style='font-size:9.0pt;color:black'>Benjamin Krepp</span></b><b><span style='font-size:9.0pt;color:#1F9000'> </span></b><span style='font-size:9.0pt;color:#1F9000'> | </span><span style='font-size:9.0pt;color:black'>Manager of GIS and IT</span><span style='font-size:10.5pt;color:black'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;color:#1F9000'>CENTRAL TRANSPORTATION PLANNING STAFF</span><span style='font-size:10.5pt;color:black'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;color:black'>617.973.7137</span><b><span style='font-size:9.0pt;color:#1F9000'> </span></b><span style='font-size:9.0pt;color:#1F9000'> | </span><u><span style='font-size:9.0pt;color:blue'><a href="mailto:bkrepp@ctps.org">bkrepp@ctps.org</a></span></u><span style='font-size:10.5pt;color:black'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;color:black'><a href="http://www.ctps.org/bostonmpo"><span style='color:blue'>www.ctps.org/bostonmpo</span></a></span><span style='font-size:10.5pt;color:black'><o:p></o:p></span></p><p class=MsoNormal><span style='font-size:9.0pt;font-family:"Myriad Pro";color:black'><img border=0 width=233 height=73 id="Picture_x0020_1" src="cid:image001.png@01CD967D.A867B660" alt="Description: Description: cid:5F54AF76-729F-48CE-9BEE-5E4887E4DA63"></span><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>