/*
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Author: Mike Adair madairATdmsolutions.ca
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Richard Greenwood rich@greenwoodmap.com
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License: LGPL as per: http://www.gnu.org/copyleft/lesser.html
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$Id: Proj.js 2956 2007-07-09 12:17:52Z steven $
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*/
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/**
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* Namespace: Proj4js
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*
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* Proj4js is a JavaScript library to transform point coordinates from one
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* coordinate system to another, including datum transformations.
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*
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* This library is a port of both the Proj.4 and GCTCP C libraries to JavaScript.
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* Enabling these transformations in the browser allows geographic data stored
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* in different projections to be combined in browser-based web mapping
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* applications.
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*
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* Proj4js must have access to coordinate system initialization strings (which
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* are the same as for PROJ.4 command line). Thes can be included in your
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* application using a <script> tag or Proj4js can load CS initialization
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* strings from a local directory or a web service such as spatialreference.org.
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*
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* Similarly, Proj4js must have access to projection transform code. These can
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* be included individually using a <script> tag in your page, built into a
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* custom build of Proj4js or loaded dynamically at run-time. Using the
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* -combined and -compressed versions of Proj4js includes all projection class
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* code by default.
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*
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* Note that dynamic loading of defs and code happens ascynchrously, check the
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* Proj.readyToUse flag before using the Proj object. If the defs and code
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* required by your application are loaded through script tags, dynamic loading
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* is not required and the Proj object will be readyToUse on return from the
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* constructor.
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*
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* All coordinates are handled as points which have a .x and a .y property
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* which will be modified in place.
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*
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* Override Proj4js.reportError for output of alerts and warnings.
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*
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* See http://trac.osgeo.org/proj4js/wiki/UserGuide for full details.
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*/
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/**
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* Global namespace object for Proj4js library
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*/
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var Proj4js = {
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/**
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* Property: defaultDatum
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* The datum to use when no others a specified
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*/
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defaultDatum: 'WGS84', //default datum
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/**
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* Method: transform(source, dest, point)
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* Transform a point coordinate from one map projection to another. This is
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* really the only public method you should need to use.
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*
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* Parameters:
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* source - {Proj4js.Proj} source map projection for the transformation
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* dest - {Proj4js.Proj} destination map projection for the transformation
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* point - {Object} point to transform, may be geodetic (long, lat) or
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* projected Cartesian (x,y), but should always have x,y properties.
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*/
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transform: function(source, dest, point) {
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if (!source.readyToUse) {
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this.reportError("Proj4js initialization for:"+source.srsCode+" not yet complete");
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return point;
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}
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if (!dest.readyToUse) {
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this.reportError("Proj4js initialization for:"+dest.srsCode+" not yet complete");
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return point;
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}
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// console.log(source);
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if (source.swapXY==true)
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{
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//console.log("source");
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var tmpP=point.x;
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point.x=point.y;
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point.y=tmpP;
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}
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// Workaround for datum shifts towgs84, if either source or destination projection is not wgs84
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if (source.datum && dest.datum && (
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((source.datum.datum_type == Proj4js.common.PJD_3PARAM || source.datum.datum_type == Proj4js.common.PJD_7PARAM) && dest.datumCode != "WGS84") ||
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((dest.datum.datum_type == Proj4js.common.PJD_3PARAM || dest.datum.datum_type == Proj4js.common.PJD_7PARAM) && source.datumCode != "WGS84"))) {
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var wgs84 = Proj4js.WGS84;
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this.transform(source, wgs84, point);
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source = wgs84;
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}
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// DGR, 2010/11/12
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if (source.axis!="enu") {
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this.adjust_axis(source,false,point);
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}
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// Transform source points to long/lat, if they aren't already.
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if ( source.projName=="longlat") {
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point.x *= Proj4js.common.D2R; // convert degrees to radians
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point.y *= Proj4js.common.D2R;
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} else {
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if (source.to_meter) {
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point.x *= source.to_meter;
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point.y *= source.to_meter;
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}
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source.inverse(point); // Convert Cartesian to longlat
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}
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// Adjust for the prime meridian if necessary
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if (source.from_greenwich) {
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point.x += source.from_greenwich;
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}
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// Convert datums if needed, and if possible.
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point = this.datum_transform( source.datum, dest.datum, point );
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// Adjust for the prime meridian if necessary
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if (dest.from_greenwich) {
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point.x -= dest.from_greenwich;
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}
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if( dest.projName=="longlat" ) {
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// convert radians to decimal degrees
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point.x *= Proj4js.common.R2D;
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point.y *= Proj4js.common.R2D;
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} else { // else project
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dest.forward(point);
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if (dest.to_meter) {
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point.x /= dest.to_meter;
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point.y /= dest.to_meter;
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}
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}
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// DGR, 2010/11/12
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if (dest.axis!="enu") {
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this.adjust_axis(dest,true,point);
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}
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if (dest.swapXY==true)
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{
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// console.log("dest");
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var tmpP=point.x;
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point.x=point.y;
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point.y=tmpP;
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}
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return point;
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}, // transform()
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/** datum_transform()
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source coordinate system definition,
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destination coordinate system definition,
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point to transform in geodetic coordinates (long, lat, height)
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*/
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datum_transform : function( source, dest, point ) {
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// Short cut if the datums are identical.
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if( source.compare_datums( dest ) ) {
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return point; // in this case, zero is sucess,
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// whereas cs_compare_datums returns 1 to indicate TRUE
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// confusing, should fix this
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}
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// Explicitly skip datum transform by setting 'datum=none' as parameter for either source or dest
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if( source.datum_type == Proj4js.common.PJD_NODATUM
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|| dest.datum_type == Proj4js.common.PJD_NODATUM) {
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return point;
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}
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// Do we need to go through geocentric coordinates?
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if( source.es != dest.es || source.a != dest.a
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|| source.datum_type == Proj4js.common.PJD_3PARAM
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|| source.datum_type == Proj4js.common.PJD_7PARAM
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|| dest.datum_type == Proj4js.common.PJD_3PARAM
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|| dest.datum_type == Proj4js.common.PJD_7PARAM)
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{
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// Convert to geocentric coordinates.
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source.geodetic_to_geocentric( point );
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// CHECK_RETURN;
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// Convert between datums
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if( source.datum_type == Proj4js.common.PJD_3PARAM || source.datum_type == Proj4js.common.PJD_7PARAM ) {
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source.geocentric_to_wgs84(point);
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// CHECK_RETURN;
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}
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if( dest.datum_type == Proj4js.common.PJD_3PARAM || dest.datum_type == Proj4js.common.PJD_7PARAM ) {
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dest.geocentric_from_wgs84(point);
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// CHECK_RETURN;
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}
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// Convert back to geodetic coordinates
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dest.geocentric_to_geodetic( point );
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// CHECK_RETURN;
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}
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return point;
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}, // cs_datum_transform
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/**
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* Function: adjust_axis
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* Normalize or de-normalized the x/y/z axes. The normal form is "enu"
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* (easting, northing, up).
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* Parameters:
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* crs {Proj4js.Proj} the coordinate reference system
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* denorm {Boolean} when false, normalize
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* point {Object} the coordinates to adjust
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*/
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adjust_axis: function(crs, denorm, point) {
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var xin= point.x, yin= point.y, zin= point.z || 0.0;
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var v, t;
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for (var i= 0; i<3; i++) {
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if (denorm && i==2 && point.z===undefined) { continue; }
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if (i==0) { v= xin; t= 'x'; }
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else if (i==1) { v= yin; t= 'y'; }
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else { v= zin; t= 'z'; }
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switch(crs.axis[i]) {
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case 'e':
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point[t]= v;
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break;
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case 'w':
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point[t]= -v;
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break;
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case 'n':
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point[t]= v;
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break;
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case 's':
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point[t]= -v;
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break;
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case 'u':
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if (point[t]!==undefined) { point.z= v; }
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break;
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case 'd':
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if (point[t]!==undefined) { point.z= -v; }
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break;
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default :
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alert("ERROR: unknow axis ("+crs.axis[i]+") - check definition of "+crs.projName);
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return null;
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}
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}
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return point;
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},
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/**
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* Function: reportError
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* An internal method to report errors back to user.
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* Override this in applications to report error messages or throw exceptions.
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*/
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reportError: function(msg) {
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//console.log(msg);
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},
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/**
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*
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* Title: Private Methods
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* The following properties and methods are intended for internal use only.
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*
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* This is a minimal implementation of JavaScript inheritance methods so that
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* Proj4js can be used as a stand-alone library.
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* These are copies of the equivalent OpenLayers methods at v2.7
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*/
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/**
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* Function: extend
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* Copy all properties of a source object to a destination object. Modifies
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* the passed in destination object. Any properties on the source object
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* that are set to undefined will not be (re)set on the destination object.
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*
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* Parameters:
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* destination - {Object} The object that will be modified
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* source - {Object} The object with properties to be set on the destination
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*
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* Returns:
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* {Object} The destination object.
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*/
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extend: function(destination, source) {
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destination = destination || {};
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if(source) {
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for(var property in source) {
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var value = source[property];
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if(value !== undefined) {
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destination[property] = value;
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}
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}
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}
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return destination;
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},
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/**
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* Constructor: Class
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* Base class used to construct all other classes. Includes support for
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* multiple inheritance.
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*
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*/
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Class: function() {
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var Class = function() {
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this.initialize.apply(this, arguments);
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};
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var extended = {};
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var parent;
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for(var i=0; i<arguments.length; ++i) {
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if(typeof arguments[i] == "function") {
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// get the prototype of the superclass
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parent = arguments[i].prototype;
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} else {
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// in this case we're extending with the prototype
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parent = arguments[i];
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}
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Proj4js.extend(extended, parent);
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}
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Class.prototype = extended;
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return Class;
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},
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/**
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* Function: bind
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* Bind a function to an object. Method to easily create closures with
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* 'this' altered.
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*
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* Parameters:
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* func - {Function} Input function.
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* object - {Object} The object to bind to the input function (as this).
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*
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* Returns:
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* {Function} A closure with 'this' set to the passed in object.
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*/
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bind: function(func, object) {
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// create a reference to all arguments past the second one
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var args = Array.prototype.slice.apply(arguments, [2]);
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return function() {
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// Push on any additional arguments from the actual function call.
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// These will come after those sent to the bind call.
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var newArgs = args.concat(
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Array.prototype.slice.apply(arguments, [0])
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);
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return func.apply(object, newArgs);
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};
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},
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/**
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* The following properties and methods handle dynamic loading of JSON objects.
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*/
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/**
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* Property: scriptName
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* {String} The filename of this script without any path.
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*/
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scriptName: "proj4js.js",
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/**
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* Property: defsLookupService
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* AJAX service to retreive projection definition parameters from
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*/
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defsLookupService: 'http://spatialreference.org/ref',
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/**
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* Property: libPath
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* internal: http server path to library code.
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*/
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libPath: null,
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/**
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* Function: getScriptLocation
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* Return the path to this script.
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*
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* Returns:
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* Path to this script
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*/
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getScriptLocation: function () {
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if (this.libPath) return this.libPath;
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var scriptName = this.scriptName;
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var scriptNameLen = scriptName.length;
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var scripts = document.getElementsByTagName('script');
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for (var i = 0; i < scripts.length; i++) {
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var src = scripts[i].getAttribute('src');
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if (src) {
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var index = src.lastIndexOf(scriptName);
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// is it found, at the end of the URL?
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if ((index > -1) && (index + scriptNameLen == src.length)) {
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this.libPath = src.slice(0, -scriptNameLen);
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break;
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}
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}
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}
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return this.libPath||"";
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},
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/**
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* Function: loadScript
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* Load a JS file from a URL into a <script> tag in the page.
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*
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* Parameters:
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* url - {String} The URL containing the script to load
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* onload - {Function} A method to be executed when the script loads successfully
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* onfail - {Function} A method to be executed when there is an error loading the script
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* loadCheck - {Function} A boolean method that checks to see if the script
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* has loaded. Typically this just checks for the existance of
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* an object in the file just loaded.
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*/
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loadScript: function(url, onload, onfail, loadCheck) {
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var script = document.createElement('script');
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script.defer = false;
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script.type = "text/javascript";
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script.id = url;
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script.src = url;
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script.onload = onload;
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script.onerror = onfail;
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script.loadCheck = loadCheck;
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if (/MSIE/.test(navigator.userAgent)) {
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script.onreadystatechange = this.checkReadyState;
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}
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document.getElementsByTagName('head')[0].appendChild(script);
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},
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/**
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* Function: checkReadyState
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* IE workaround since there is no onerror handler. Calls the user defined
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* loadCheck method to determine if the script is loaded.
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*
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*/
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checkReadyState: function() {
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if (this.readyState == 'loaded') {
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if (!this.loadCheck()) {
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this.onerror();
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} else {
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this.onload();
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}
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}
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}
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};
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/**
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* Class: Proj4js.Proj
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*
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* Proj objects provide transformation methods for point coordinates
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* between geodetic latitude/longitude and a projected coordinate system.
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* once they have been initialized with a projection code.
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*
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* Initialization of Proj objects is with a projection code, usually EPSG codes,
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* which is the key that will be used with the Proj4js.defs array.
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*
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* The code passed in will be stripped of colons and converted to uppercase
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* to locate projection definition files.
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*
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* A projection object has properties for units and title strings.
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*/
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Proj4js.Proj = Proj4js.Class({
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/**
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* Property: readyToUse
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* Flag to indicate if initialization is complete for this Proj object
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*/
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readyToUse: false,
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/**
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* Property: title
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* The title to describe the projection
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*/
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title: null,
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/**
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* Property: projName
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* The projection class for this projection, e.g. lcc (lambert conformal conic,
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* or merc for mercator). These are exactly equivalent to their Proj4
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* counterparts.
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*/
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projName: null,
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/**
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* Property: units
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* The units of the projection. Values include 'm' and 'degrees'
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*/
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units: null,
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/**
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* Property: datum
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* The datum specified for the projection
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*/
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datum: null,
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/**
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* Property: x0
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* The x coordinate origin
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*/
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x0: 0,
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/**
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* Property: y0
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* The y coordinate origin
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*/
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y0: 0,
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/**
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* Property: localCS
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* Flag to indicate if the projection is a local one in which no transforms
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* are required.
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*/
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localCS: false,
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/**
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* Property: queue
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* Buffer (FIFO) to hold callbacks waiting to be called when projection loaded.
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*/
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queue: null,
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/**
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* Constructor: initialize
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* Constructor for Proj4js.Proj objects
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*
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* Parameters:
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* srsCode - a code for map projection definition parameters. These are usually
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* (but not always) EPSG codes.
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*/
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initialize: function(srsCode, callback) {
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this.srsCodeInput = srsCode;
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//Register callbacks prior to attempting to process definition
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this.queue = [];
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if( callback ){
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this.queue.push( callback );
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}
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//check to see if this is a WKT string
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if ((srsCode.indexOf('GEOGCS') >= 0) ||
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(srsCode.indexOf('GEOCCS') >= 0) ||
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(srsCode.indexOf('PROJCS') >= 0) ||
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(srsCode.indexOf('LOCAL_CS') >= 0)) {
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this.parseWKT(srsCode);
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this.deriveConstants();
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this.loadProjCode(this.projName);
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return;
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}
|
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// DGR 2008-08-03 : support urn and url
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if (srsCode.indexOf('urn:') == 0) {
|
//urn:ORIGINATOR:def:crs:CODESPACE:VERSION:ID
|
var urn = srsCode.split(':');
|
if ((urn[1] == 'ogc' || urn[1] =='x-ogc') &&
|
(urn[2] =='def') &&
|
(urn[3] =='crs')) {
|
srsCode = urn[4]+':'+urn[urn.length-1];
|
}
|
} else if (srsCode.indexOf('http://') == 0) {
|
//url#ID
|
var url = srsCode.split('#');
|
if (url[0].match(/epsg.org/)) {
|
// http://www.epsg.org/#
|
srsCode = 'EPSG:'+url[1];
|
} else if (url[0].match(/RIG.xml/)) {
|
//http://librairies.ign.fr/geoportail/resources/RIG.xml#
|
//http://interop.ign.fr/registers/ign/RIG.xml#
|
srsCode = 'IGNF:'+url[1];
|
}
|
}
|
this.srsCode = srsCode.toUpperCase();
|
if (this.srsCode.indexOf("EPSG") == 0) {
|
this.srsCode = this.srsCode;
|
this.srsAuth = 'epsg';
|
this.srsProjNumber = this.srsCode.substring(5);
|
// DGR 2007-11-20 : authority IGNF
|
} else if (this.srsCode.indexOf("IGNF") == 0) {
|
this.srsCode = this.srsCode;
|
this.srsAuth = 'IGNF';
|
this.srsProjNumber = this.srsCode.substring(5);
|
// DGR 2008-06-19 : pseudo-authority CRS for WMS
|
} else if (this.srsCode.indexOf("CRS") == 0) {
|
this.srsCode = this.srsCode;
|
this.srsAuth = 'CRS';
|
this.srsProjNumber = this.srsCode.substring(4);
|
} else {
|
this.srsAuth = '';
|
this.srsProjNumber = this.srsCode;
|
}
|
|
this.loadProjDefinition();
|
},
|
|
/**
|
* Function: loadProjDefinition
|
* Loads the coordinate system initialization string if required.
|
* Note that dynamic loading happens asynchronously so an application must
|
* wait for the readyToUse property is set to true.
|
* To prevent dynamic loading, include the defs through a script tag in
|
* your application.
|
*
|
*/
|
loadProjDefinition: function() {
|
//check in memory
|
if (Proj4js.defs[this.srsCode]) {
|
this.defsLoaded();
|
return;
|
}
|
|
//else check for def on the server
|
var url = Proj4js.getScriptLocation() + 'defs/' + this.srsAuth.toUpperCase() + this.srsProjNumber + '.js';
|
Proj4js.loadScript(url,
|
Proj4js.bind(this.defsLoaded, this),
|
Proj4js.bind(this.loadFromService, this),
|
Proj4js.bind(this.checkDefsLoaded, this) );
|
},
|
|
/**
|
* Function: loadFromService
|
* Creates the REST URL for loading the definition from a web service and
|
* loads it.
|
*
|
*/
|
loadFromService: function() {
|
//else load from web service
|
var url = Proj4js.defsLookupService +'/' + this.srsAuth +'/'+ this.srsProjNumber + '/proj4js/';
|
Proj4js.loadScript(url,
|
Proj4js.bind(this.defsLoaded, this),
|
Proj4js.bind(this.defsFailed, this),
|
Proj4js.bind(this.checkDefsLoaded, this) );
|
},
|
|
/**
|
* Function: defsLoaded
|
* Continues the Proj object initilization once the def file is loaded
|
*
|
*/
|
defsLoaded: function() {
|
this.parseDefs();
|
this.loadProjCode(this.projName);
|
},
|
|
/**
|
* Function: checkDefsLoaded
|
* This is the loadCheck method to see if the def object exists
|
*
|
*/
|
checkDefsLoaded: function() {
|
if (Proj4js.defs[this.srsCode]) {
|
return true;
|
} else {
|
return false;
|
}
|
},
|
|
/**
|
* Function: defsFailed
|
* Report an error in loading the defs file, but continue on using WGS84
|
*
|
*/
|
defsFailed: function() {
|
Proj4js.reportError('failed to load projection definition for: '+this.srsCode);
|
Proj4js.defs[this.srsCode] = Proj4js.defs['WGS84']; //set it to something so it can at least continue
|
this.defsLoaded();
|
},
|
|
/**
|
* Function: loadProjCode
|
* Loads projection class code dynamically if required.
|
* Projection code may be included either through a script tag or in
|
* a built version of proj4js
|
*
|
*/
|
loadProjCode: function(projName) {
|
if (Proj4js.Proj[projName]) {
|
this.initTransforms();
|
return;
|
}
|
|
//the URL for the projection code
|
var url = Proj4js.getScriptLocation() + 'projCode/' + projName + '.js';
|
Proj4js.loadScript(url,
|
Proj4js.bind(this.loadProjCodeSuccess, this, projName),
|
Proj4js.bind(this.loadProjCodeFailure, this, projName),
|
Proj4js.bind(this.checkCodeLoaded, this, projName) );
|
},
|
|
/**
|
* Function: loadProjCodeSuccess
|
* Loads any proj dependencies or continue on to final initialization.
|
*
|
*/
|
loadProjCodeSuccess: function(projName) {
|
if (Proj4js.Proj[projName].dependsOn){
|
this.loadProjCode(Proj4js.Proj[projName].dependsOn);
|
} else {
|
this.initTransforms();
|
}
|
},
|
|
/**
|
* Function: defsFailed
|
* Report an error in loading the proj file. Initialization of the Proj
|
* object has failed and the readyToUse flag will never be set.
|
*
|
*/
|
loadProjCodeFailure: function(projName) {
|
Proj4js.reportError("failed to find projection file for: " + projName);
|
//TBD initialize with identity transforms so proj will still work?
|
},
|
|
/**
|
* Function: checkCodeLoaded
|
* This is the loadCheck method to see if the projection code is loaded
|
*
|
*/
|
checkCodeLoaded: function(projName) {
|
if (Proj4js.Proj[projName]) {
|
return true;
|
} else {
|
return false;
|
}
|
},
|
|
/**
|
* Function: initTransforms
|
* Finalize the initialization of the Proj object
|
*
|
*/
|
initTransforms: function() {
|
Proj4js.extend(this, Proj4js.Proj[this.projName]);
|
this.init();
|
this.readyToUse = true;
|
if( this.queue ) {
|
var item;
|
while( (item = this.queue.shift()) ) {
|
item.call( this, this );
|
}
|
}
|
},
|
|
/**
|
* Function: parseWKT
|
* Parses a WKT string to get initialization parameters
|
*
|
*/
|
wktRE: /^(\w+)\[(.*)\]$/,
|
parseWKT: function(wkt) {
|
var wktMatch = wkt.match(this.wktRE);
|
if (!wktMatch) return;
|
var wktObject = wktMatch[1];
|
var wktContent = wktMatch[2];
|
var wktTemp = wktContent.split(",");
|
var wktName;
|
if (wktObject.toUpperCase() == "TOWGS84") {
|
wktName = wktObject; //no name supplied for the TOWGS84 array
|
} else {
|
wktName = wktTemp.shift();
|
}
|
wktName = wktName.replace(/^\"/,"");
|
wktName = wktName.replace(/\"$/,"");
|
|
/*
|
wktContent = wktTemp.join(",");
|
var wktArray = wktContent.split("],");
|
for (var i=0; i<wktArray.length-1; ++i) {
|
wktArray[i] += "]";
|
}
|
*/
|
|
var wktArray = new Array();
|
var bkCount = 0;
|
var obj = "";
|
for (var i=0; i<wktTemp.length; ++i) {
|
var token = wktTemp[i];
|
for (var j=0; j<token.length; ++j) {
|
if (token.charAt(j) == "[") ++bkCount;
|
if (token.charAt(j) == "]") --bkCount;
|
}
|
obj += token;
|
if (bkCount === 0) {
|
wktArray.push(obj);
|
obj = "";
|
} else {
|
obj += ",";
|
}
|
}
|
|
//do something based on the type of the wktObject being parsed
|
//add in variations in the spelling as required
|
switch (wktObject) {
|
case 'LOCAL_CS':
|
this.projName = 'identity'
|
this.localCS = true;
|
this.srsCode = wktName;
|
break;
|
case 'GEOGCS':
|
this.projName = 'longlat'
|
this.geocsCode = wktName;
|
if (!this.srsCode) this.srsCode = wktName;
|
break;
|
case 'PROJCS':
|
this.srsCode = wktName;
|
break;
|
case 'GEOCCS':
|
break;
|
case 'PROJECTION':
|
this.projName = Proj4js.wktProjections[wktName]
|
break;
|
case 'DATUM':
|
this.datumName = wktName;
|
break;
|
case 'LOCAL_DATUM':
|
this.datumCode = 'none';
|
break;
|
case 'SPHEROID':
|
this.ellps = wktName;
|
this.a = parseFloat(wktArray.shift());
|
this.rf = parseFloat(wktArray.shift());
|
break;
|
case 'PRIMEM':
|
this.from_greenwich = parseFloat(wktArray.shift()); //to radians?
|
break;
|
case 'UNIT':
|
this.units = wktName;
|
this.unitsPerMeter = parseFloat(wktArray.shift());
|
break;
|
case 'PARAMETER':
|
var name = wktName.toLowerCase();
|
var value = parseFloat(wktArray.shift());
|
//there may be many variations on the wktName values, add in case
|
//statements as required
|
switch (name) {
|
case 'false_easting':
|
this.x0 = value;
|
break;
|
case 'false_northing':
|
this.y0 = value;
|
break;
|
case 'scale_factor':
|
this.k0 = value;
|
break;
|
case 'central_meridian':
|
this.long0 = value*Proj4js.common.D2R;
|
break;
|
case 'latitude_of_origin':
|
this.lat0 = value*Proj4js.common.D2R;
|
break;
|
case 'more_here':
|
break;
|
default:
|
break;
|
}
|
break;
|
case 'TOWGS84':
|
this.datum_params = wktArray;
|
break;
|
//DGR 2010-11-12: AXIS
|
case 'AXIS':
|
var name= wktName.toLowerCase();
|
var value= wktArray.shift();
|
switch (value) {
|
case 'EAST' : value= 'e'; break;
|
case 'WEST' : value= 'w'; break;
|
case 'NORTH': value= 'n'; break;
|
case 'SOUTH': value= 's'; break;
|
case 'UP' : value= 'u'; break;
|
case 'DOWN' : value= 'd'; break;
|
case 'OTHER':
|
default : value= ' '; break;//FIXME
|
}
|
if (!this.axis) { this.axis= "enu"; }
|
switch(name) {
|
case 'x': this.axis= value + this.axis.substr(1,2); break;
|
case 'y': this.axis= this.axis.substr(0,1) + value + this.axis.substr(2,1); break;
|
case 'z': this.axis= this.axis.substr(0,2) + value ; break;
|
default : break;
|
}
|
case 'MORE_HERE':
|
break;
|
default:
|
break;
|
}
|
for (var i=0; i<wktArray.length; ++i) {
|
this.parseWKT(wktArray[i]);
|
}
|
},
|
|
/**
|
* Function: parseDefs
|
* Parses the PROJ.4 initialization string and sets the associated properties.
|
*
|
*/
|
parseDefs: function() {
|
this.defData = Proj4js.defs[this.srsCode];
|
var paramName, paramVal;
|
if (!this.defData) {
|
return;
|
}
|
var paramArray=this.defData.split("+");
|
|
for (var prop=0; prop<paramArray.length; prop++) {
|
var property = paramArray[prop].split("=");
|
paramName = property[0].toLowerCase();
|
paramVal = property[1];
|
|
switch (paramName.replace(/\s/gi,"")) { // trim out spaces
|
case "": break; // throw away nameless parameter
|
case "title": this.title = paramVal; break;
|
case "proj": this.projName = paramVal.replace(/\s/gi,""); break;
|
case "units": this.units = paramVal.replace(/\s/gi,""); break;
|
case "datum": this.datumCode = paramVal.replace(/\s/gi,""); break;
|
case "nadgrids": this.nagrids = paramVal.replace(/\s/gi,""); break;
|
case "ellps": this.ellps = paramVal.replace(/\s/gi,""); break;
|
case "a": this.a = parseFloat(paramVal); break; // semi-major radius
|
case "b": this.b = parseFloat(paramVal); break; // semi-minor radius
|
// DGR 2007-11-20
|
case "rf": this.rf = parseFloat(paramVal); break; // inverse flattening rf= a/(a-b)
|
case "lat_0": this.lat0 = paramVal*Proj4js.common.D2R; break; // phi0, central latitude
|
case "lat_1": this.lat1 = paramVal*Proj4js.common.D2R; break; //standard parallel 1
|
case "lat_2": this.lat2 = paramVal*Proj4js.common.D2R; break; //standard parallel 2
|
case "lat_ts": this.lat_ts = paramVal*Proj4js.common.D2R; break; // used in merc and eqc
|
case "lon_0": this.long0 = paramVal*Proj4js.common.D2R; break; // lam0, central longitude
|
case "alpha": this.alpha = parseFloat(paramVal)*Proj4js.common.D2R; break; //for somerc projection
|
case "lonc": this.longc = paramVal*Proj4js.common.D2R; break; //for somerc projection
|
case "x_0": this.x0 = parseFloat(paramVal); break; // false easting
|
case "y_0": this.y0 = parseFloat(paramVal); break; // false northing
|
case "k_0": this.k0 = parseFloat(paramVal); break; // projection scale factor
|
case "k": this.k0 = parseFloat(paramVal); break; // both forms returned
|
case "r_a": this.R_A = true; break; // sphere--area of ellipsoid
|
case "zone": this.zone = parseInt(paramVal,10); break; // UTM Zone
|
case "south": this.utmSouth = true; break; // UTM north/south
|
case "towgs84":this.datum_params = paramVal.split(","); break;
|
case "to_meter": this.to_meter = parseFloat(paramVal); break; // cartesian scaling
|
case "from_greenwich": this.from_greenwich = paramVal*Proj4js.common.D2R; break;
|
// DGR 2008-07-09 : if pm is not a well-known prime meridian take
|
// the value instead of 0.0, then convert to radians
|
case "pm": paramVal = paramVal.replace(/\s/gi,"");
|
this.from_greenwich = Proj4js.PrimeMeridian[paramVal] ?
|
Proj4js.PrimeMeridian[paramVal] : parseFloat(paramVal);
|
this.from_greenwich *= Proj4js.common.D2R;
|
break;
|
// DGR 2010-11-12: axis
|
case "axis": paramVal = paramVal.replace(/\s/gi,"");
|
var legalAxis= "ewnsud";
|
if (paramVal.length==3 &&
|
legalAxis.indexOf(paramVal.substr(0,1))!=-1 &&
|
legalAxis.indexOf(paramVal.substr(1,1))!=-1 &&
|
legalAxis.indexOf(paramVal.substr(2,1))!=-1) {
|
this.axis= paramVal;
|
} //FIXME: be silent ?
|
break
|
case "no_defs": break;
|
default: //alert("Unrecognized parameter: " + paramName);
|
} // switch()
|
} // for paramArray
|
this.deriveConstants();
|
},
|
|
/**
|
* Function: deriveConstants
|
* Sets several derived constant values and initialization of datum and ellipse
|
* parameters.
|
*
|
*/
|
deriveConstants: function() {
|
if (this.nagrids == '@null') this.datumCode = 'none';
|
if (this.datumCode && this.datumCode != 'none') {
|
var datumDef = Proj4js.Datum[this.datumCode];
|
if (datumDef) {
|
this.datum_params = datumDef.towgs84 ? datumDef.towgs84.split(',') : null;
|
this.ellps = datumDef.ellipse;
|
this.datumName = datumDef.datumName ? datumDef.datumName : this.datumCode;
|
}
|
}
|
if (!this.a) { // do we have an ellipsoid?
|
var ellipse = Proj4js.Ellipsoid[this.ellps] ? Proj4js.Ellipsoid[this.ellps] : Proj4js.Ellipsoid['WGS84'];
|
Proj4js.extend(this, ellipse);
|
}
|
if (this.rf && !this.b) this.b = (1.0 - 1.0/this.rf) * this.a;
|
if (this.rf === 0 || Math.abs(this.a - this.b)<Proj4js.common.EPSLN) {
|
this.sphere = true;
|
this.b= this.a;
|
}
|
this.a2 = this.a * this.a; // used in geocentric
|
this.b2 = this.b * this.b; // used in geocentric
|
this.es = (this.a2-this.b2)/this.a2; // e ^ 2
|
this.e = Math.sqrt(this.es); // eccentricity
|
if (this.R_A) {
|
this.a *= 1. - this.es * (Proj4js.common.SIXTH + this.es * (Proj4js.common.RA4 + this.es * Proj4js.common.RA6));
|
this.a2 = this.a * this.a;
|
this.b2 = this.b * this.b;
|
this.es = 0.;
|
}
|
this.ep2=(this.a2-this.b2)/this.b2; // used in geocentric
|
if (!this.k0) this.k0 = 1.0; //default value
|
//DGR 2010-11-12: axis
|
if (!this.axis) { this.axis= "enu"; }
|
|
this.datum = new Proj4js.datum(this);
|
}
|
});
|
|
Proj4js.Proj.longlat = {
|
init: function() {
|
//no-op for longlat
|
},
|
forward: function(pt) {
|
//identity transform
|
return pt;
|
},
|
inverse: function(pt) {
|
//identity transform
|
return pt;
|
}
|
};
|
Proj4js.Proj.identity = Proj4js.Proj.longlat;
|
|
/**
|
Proj4js.defs is a collection of coordinate system definition objects in the
|
PROJ.4 command line format.
|
Generally a def is added by means of a separate .js file for example:
|
|
<SCRIPT type="text/javascript" src="defs/EPSG26912.js"></SCRIPT>
|
|
def is a CS definition in PROJ.4 WKT format, for example:
|
+proj="tmerc" //longlat, etc.
|
+a=majorRadius
|
+b=minorRadius
|
+lat0=somenumber
|
+long=somenumber
|
*/
|
Proj4js.defs = {
|
// These are so widely used, we'll go ahead and throw them in
|
// without requiring a separate .js file
|
'WGS84': "+title=long/lat:WGS84 +proj=longlat +ellps=WGS84 +datum=WGS84 +units=degrees",
|
'EPSG:4326': "+title=long/lat:WGS84 +proj=longlat +a=6378137.0 +b=6356752.31424518 +ellps=WGS84 +datum=WGS84 +units=degrees",
|
'EPSG:4269': "+title=long/lat:NAD83 +proj=longlat +a=6378137.0 +b=6356752.31414036 +ellps=GRS80 +datum=NAD83 +units=degrees",
|
'EPSG:3875': "+title= Google Mercator +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m +nadgrids=@null +no_defs"
|
};
|
Proj4js.defs['EPSG:3785'] = Proj4js.defs['EPSG:3875']; //maintain backward compat, official code is 3875
|
Proj4js.defs['GOOGLE'] = Proj4js.defs['EPSG:3875'];
|
Proj4js.defs['EPSG:900913'] = Proj4js.defs['EPSG:3875'];
|
Proj4js.defs['EPSG:102113'] = Proj4js.defs['EPSG:3875'];
|
|
Proj4js.common = {
|
PI : 3.141592653589793238, //Math.PI,
|
HALF_PI : 1.570796326794896619, //Math.PI*0.5,
|
TWO_PI : 6.283185307179586477, //Math.PI*2,
|
FORTPI : 0.78539816339744833,
|
R2D : 57.29577951308232088,
|
D2R : 0.01745329251994329577,
|
SEC_TO_RAD : 4.84813681109535993589914102357e-6, /* SEC_TO_RAD = Pi/180/3600 */
|
EPSLN : 1.0e-10,
|
MAX_ITER : 20,
|
// following constants from geocent.c
|
COS_67P5 : 0.38268343236508977, /* cosine of 67.5 degrees */
|
AD_C : 1.0026000, /* Toms region 1 constant */
|
|
/* datum_type values */
|
PJD_UNKNOWN : 0,
|
PJD_3PARAM : 1,
|
PJD_7PARAM : 2,
|
PJD_GRIDSHIFT: 3,
|
PJD_WGS84 : 4, // WGS84 or equivalent
|
PJD_NODATUM : 5, // WGS84 or equivalent
|
SRS_WGS84_SEMIMAJOR : 6378137.0, // only used in grid shift transforms
|
|
// ellipoid pj_set_ell.c
|
SIXTH : .1666666666666666667, /* 1/6 */
|
RA4 : .04722222222222222222, /* 17/360 */
|
RA6 : .02215608465608465608, /* 67/3024 */
|
RV4 : .06944444444444444444, /* 5/72 */
|
RV6 : .04243827160493827160, /* 55/1296 */
|
|
// Function to compute the constant small m which is the radius of
|
// a parallel of latitude, phi, divided by the semimajor axis.
|
// -----------------------------------------------------------------
|
msfnz : function(eccent, sinphi, cosphi) {
|
var con = eccent * sinphi;
|
return cosphi/(Math.sqrt(1.0 - con * con));
|
},
|
|
// Function to compute the constant small t for use in the forward
|
// computations in the Lambert Conformal Conic and the Polar
|
// Stereographic projections.
|
// -----------------------------------------------------------------
|
tsfnz : function(eccent, phi, sinphi) {
|
var con = eccent * sinphi;
|
var com = .5 * eccent;
|
con = Math.pow(((1.0 - con) / (1.0 + con)), com);
|
return (Math.tan(.5 * (this.HALF_PI - phi))/con);
|
},
|
|
// Function to compute the latitude angle, phi2, for the inverse of the
|
// Lambert Conformal Conic and Polar Stereographic projections.
|
// ----------------------------------------------------------------
|
phi2z : function(eccent, ts) {
|
var eccnth = .5 * eccent;
|
var con, dphi;
|
var phi = this.HALF_PI - 2 * Math.atan(ts);
|
for (var i = 0; i <= 15; i++) {
|
con = eccent * Math.sin(phi);
|
dphi = this.HALF_PI - 2 * Math.atan(ts *(Math.pow(((1.0 - con)/(1.0 + con)),eccnth))) - phi;
|
phi += dphi;
|
if (Math.abs(dphi) <= .0000000001) return phi;
|
}
|
alert("phi2z has NoConvergence");
|
return (-9999);
|
},
|
|
/* Function to compute constant small q which is the radius of a
|
parallel of latitude, phi, divided by the semimajor axis.
|
------------------------------------------------------------*/
|
qsfnz : function(eccent,sinphi) {
|
var con;
|
if (eccent > 1.0e-7) {
|
con = eccent * sinphi;
|
return (( 1.0- eccent * eccent) * (sinphi /(1.0 - con * con) - (.5/eccent)*Math.log((1.0 - con)/(1.0 + con))));
|
} else {
|
return(2.0 * sinphi);
|
}
|
},
|
|
/* Function to eliminate roundoff errors in asin
|
----------------------------------------------*/
|
asinz : function(x) {
|
if (Math.abs(x)>1.0) {
|
x=(x>1.0)?1.0:-1.0;
|
}
|
return Math.asin(x);
|
},
|
|
// following functions from gctpc cproj.c for transverse mercator projections
|
e0fn : function(x) {return(1.0-0.25*x*(1.0+x/16.0*(3.0+1.25*x)));},
|
e1fn : function(x) {return(0.375*x*(1.0+0.25*x*(1.0+0.46875*x)));},
|
e2fn : function(x) {return(0.05859375*x*x*(1.0+0.75*x));},
|
e3fn : function(x) {return(x*x*x*(35.0/3072.0));},
|
mlfn : function(e0,e1,e2,e3,phi) {return(e0*phi-e1*Math.sin(2.0*phi)+e2*Math.sin(4.0*phi)-e3*Math.sin(6.0*phi));},
|
|
srat : function(esinp, exp) {
|
return(Math.pow((1.0-esinp)/(1.0+esinp), exp));
|
},
|
|
// Function to return the sign of an argument
|
sign : function(x) { if (x < 0.0) return(-1); else return(1);},
|
|
// Function to adjust longitude to -180 to 180; input in radians
|
adjust_lon : function(x) {
|
x = (Math.abs(x) < this.PI) ? x: (x - (this.sign(x)*this.TWO_PI) );
|
return x;
|
},
|
|
// IGNF - DGR : algorithms used by IGN France
|
|
// Function to adjust latitude to -90 to 90; input in radians
|
adjust_lat : function(x) {
|
x= (Math.abs(x) < this.HALF_PI) ? x: (x - (this.sign(x)*this.PI) );
|
return x;
|
},
|
|
// Latitude Isometrique - close to tsfnz ...
|
latiso : function(eccent, phi, sinphi) {
|
if (Math.abs(phi) > this.HALF_PI) return +Number.NaN;
|
if (phi==this.HALF_PI) return Number.POSITIVE_INFINITY;
|
if (phi==-1.0*this.HALF_PI) return -1.0*Number.POSITIVE_INFINITY;
|
|
var con= eccent*sinphi;
|
return Math.log(Math.tan((this.HALF_PI+phi)/2.0))+eccent*Math.log((1.0-con)/(1.0+con))/2.0;
|
},
|
|
fL : function(x,L) {
|
return 2.0*Math.atan(x*Math.exp(L)) - this.HALF_PI;
|
},
|
|
// Inverse Latitude Isometrique - close to ph2z
|
invlatiso : function(eccent, ts) {
|
var phi= this.fL(1.0,ts);
|
var Iphi= 0.0;
|
var con= 0.0;
|
do {
|
Iphi= phi;
|
con= eccent*Math.sin(Iphi);
|
phi= this.fL(Math.exp(eccent*Math.log((1.0+con)/(1.0-con))/2.0),ts)
|
} while (Math.abs(phi-Iphi)>1.0e-12);
|
return phi;
|
},
|
|
// Needed for Gauss Schreiber
|
// Original: Denis Makarov (info@binarythings.com)
|
// Web Site: http://www.binarythings.com
|
sinh : function(x)
|
{
|
var r= Math.exp(x);
|
r= (r-1.0/r)/2.0;
|
return r;
|
},
|
|
cosh : function(x)
|
{
|
var r= Math.exp(x);
|
r= (r+1.0/r)/2.0;
|
return r;
|
},
|
|
tanh : function(x)
|
{
|
var r= Math.exp(x);
|
r= (r-1.0/r)/(r+1.0/r);
|
return r;
|
},
|
|
asinh : function(x)
|
{
|
var s= (x>= 0? 1.0:-1.0);
|
return s*(Math.log( Math.abs(x) + Math.sqrt(x*x+1.0) ));
|
},
|
|
acosh : function(x)
|
{
|
return 2.0*Math.log(Math.sqrt((x+1.0)/2.0) + Math.sqrt((x-1.0)/2.0));
|
},
|
|
atanh : function(x)
|
{
|
return Math.log((x-1.0)/(x+1.0))/2.0;
|
},
|
|
// Grande Normale
|
gN : function(a,e,sinphi)
|
{
|
var temp= e*sinphi;
|
return a/Math.sqrt(1.0 - temp*temp);
|
},
|
|
//code from the PROJ.4 pj_mlfn.c file; this may be useful for other projections
|
pj_enfn: function(es) {
|
var en = new Array();
|
en[0] = this.C00 - es * (this.C02 + es * (this.C04 + es * (this.C06 + es * this.C08)));
|
en[1] = es * (this.C22 - es * (this.C04 + es * (this.C06 + es * this.C08)));
|
var t = es * es;
|
en[2] = t * (this.C44 - es * (this.C46 + es * this.C48));
|
t *= es;
|
en[3] = t * (this.C66 - es * this.C68);
|
en[4] = t * es * this.C88;
|
return en;
|
},
|
|
pj_mlfn: function(phi, sphi, cphi, en) {
|
cphi *= sphi;
|
sphi *= sphi;
|
return(en[0] * phi - cphi * (en[1] + sphi*(en[2]+ sphi*(en[3] + sphi*en[4]))));
|
},
|
|
pj_inv_mlfn: function(arg, es, en) {
|
var k = 1./(1.-es);
|
var phi = arg;
|
for (var i = Proj4js.common.MAX_ITER; i ; --i) { /* rarely goes over 2 iterations */
|
var s = Math.sin(phi);
|
var t = 1. - es * s * s;
|
//t = this.pj_mlfn(phi, s, Math.cos(phi), en) - arg;
|
//phi -= t * (t * Math.sqrt(t)) * k;
|
t = (this.pj_mlfn(phi, s, Math.cos(phi), en) - arg) * (t * Math.sqrt(t)) * k;
|
phi -= t;
|
if (Math.abs(t) < Proj4js.common.EPSLN)
|
return phi;
|
}
|
Proj4js.reportError("cass:pj_inv_mlfn: Convergence error");
|
return phi;
|
},
|
|
/* meridinal distance for ellipsoid and inverse
|
** 8th degree - accurate to < 1e-5 meters when used in conjuction
|
** with typical major axis values.
|
** Inverse determines phi to EPS (1e-11) radians, about 1e-6 seconds.
|
*/
|
C00: 1.0,
|
C02: .25,
|
C04: .046875,
|
C06: .01953125,
|
C08: .01068115234375,
|
C22: .75,
|
C44: .46875,
|
C46: .01302083333333333333,
|
C48: .00712076822916666666,
|
C66: .36458333333333333333,
|
C68: .00569661458333333333,
|
C88: .3076171875
|
|
};
|
|
/** datum object
|
*/
|
Proj4js.datum = Proj4js.Class({
|
|
initialize : function(proj) {
|
this.datum_type = Proj4js.common.PJD_WGS84; //default setting
|
if (proj.datumCode && proj.datumCode == 'none') {
|
this.datum_type = Proj4js.common.PJD_NODATUM;
|
}
|
if (proj && proj.datum_params) {
|
for (var i=0; i<proj.datum_params.length; i++) {
|
proj.datum_params[i]=parseFloat(proj.datum_params[i]);
|
}
|
if (proj.datum_params[0] != 0 || proj.datum_params[1] != 0 || proj.datum_params[2] != 0 ) {
|
this.datum_type = Proj4js.common.PJD_3PARAM;
|
}
|
if (proj.datum_params.length > 3) {
|
if (proj.datum_params[3] != 0 || proj.datum_params[4] != 0 ||
|
proj.datum_params[5] != 0 || proj.datum_params[6] != 0 ) {
|
this.datum_type = Proj4js.common.PJD_7PARAM;
|
proj.datum_params[3] *= Proj4js.common.SEC_TO_RAD;
|
proj.datum_params[4] *= Proj4js.common.SEC_TO_RAD;
|
proj.datum_params[5] *= Proj4js.common.SEC_TO_RAD;
|
proj.datum_params[6] = (proj.datum_params[6]/1000000.0) + 1.0;
|
}
|
}
|
}
|
if (proj) {
|
this.a = proj.a; //datum object also uses these values
|
this.b = proj.b;
|
this.es = proj.es;
|
this.ep2 = proj.ep2;
|
this.datum_params = proj.datum_params;
|
}
|
},
|
|
/****************************************************************/
|
// cs_compare_datums()
|
// Returns TRUE if the two datums match, otherwise FALSE.
|
compare_datums : function( dest ) {
|
if( this.datum_type != dest.datum_type ) {
|
return false; // false, datums are not equal
|
} else if( this.a != dest.a || Math.abs(this.es-dest.es) > 0.000000000050 ) {
|
// the tolerence for es is to ensure that GRS80 and WGS84
|
// are considered identical
|
return false;
|
} else if( this.datum_type == Proj4js.common.PJD_3PARAM ) {
|
return (this.datum_params[0] == dest.datum_params[0]
|
&& this.datum_params[1] == dest.datum_params[1]
|
&& this.datum_params[2] == dest.datum_params[2]);
|
} else if( this.datum_type == Proj4js.common.PJD_7PARAM ) {
|
return (this.datum_params[0] == dest.datum_params[0]
|
&& this.datum_params[1] == dest.datum_params[1]
|
&& this.datum_params[2] == dest.datum_params[2]
|
&& this.datum_params[3] == dest.datum_params[3]
|
&& this.datum_params[4] == dest.datum_params[4]
|
&& this.datum_params[5] == dest.datum_params[5]
|
&& this.datum_params[6] == dest.datum_params[6]);
|
} else if ( this.datum_type == Proj4js.common.PJD_GRIDSHIFT ||
|
dest.datum_type == Proj4js.common.PJD_GRIDSHIFT ) {
|
alert("ERROR: Grid shift transformations are not implemented.");
|
return false
|
} else {
|
return true; // datums are equal
|
}
|
}, // cs_compare_datums()
|
|
/*
|
* The function Convert_Geodetic_To_Geocentric converts geodetic coordinates
|
* (latitude, longitude, and height) to geocentric coordinates (X, Y, Z),
|
* according to the current ellipsoid parameters.
|
*
|
* Latitude : Geodetic latitude in radians (input)
|
* Longitude : Geodetic longitude in radians (input)
|
* Height : Geodetic height, in meters (input)
|
* X : Calculated Geocentric X coordinate, in meters (output)
|
* Y : Calculated Geocentric Y coordinate, in meters (output)
|
* Z : Calculated Geocentric Z coordinate, in meters (output)
|
*
|
*/
|
geodetic_to_geocentric : function(p) {
|
var Longitude = p.x;
|
var Latitude = p.y;
|
var Height = p.z ? p.z : 0; //Z value not always supplied
|
var X; // output
|
var Y;
|
var Z;
|
|
var Error_Code=0; // GEOCENT_NO_ERROR;
|
var Rn; /* Earth radius at location */
|
var Sin_Lat; /* Math.sin(Latitude) */
|
var Sin2_Lat; /* Square of Math.sin(Latitude) */
|
var Cos_Lat; /* Math.cos(Latitude) */
|
|
/*
|
** Don't blow up if Latitude is just a little out of the value
|
** range as it may just be a rounding issue. Also removed longitude
|
** test, it should be wrapped by Math.cos() and Math.sin(). NFW for PROJ.4, Sep/2001.
|
*/
|
if( Latitude < -Proj4js.common.HALF_PI && Latitude > -1.001 * Proj4js.common.HALF_PI ) {
|
Latitude = -Proj4js.common.HALF_PI;
|
} else if( Latitude > Proj4js.common.HALF_PI && Latitude < 1.001 * Proj4js.common.HALF_PI ) {
|
Latitude = Proj4js.common.HALF_PI;
|
} else if ((Latitude < -Proj4js.common.HALF_PI) || (Latitude > Proj4js.common.HALF_PI)) {
|
/* Latitude out of range */
|
Proj4js.reportError('geocent:lat out of range:'+Latitude);
|
return null;
|
}
|
|
if (Longitude > Proj4js.common.PI) Longitude -= (2*Proj4js.common.PI);
|
Sin_Lat = Math.sin(Latitude);
|
Cos_Lat = Math.cos(Latitude);
|
Sin2_Lat = Sin_Lat * Sin_Lat;
|
Rn = this.a / (Math.sqrt(1.0e0 - this.es * Sin2_Lat));
|
X = (Rn + Height) * Cos_Lat * Math.cos(Longitude);
|
Y = (Rn + Height) * Cos_Lat * Math.sin(Longitude);
|
Z = ((Rn * (1 - this.es)) + Height) * Sin_Lat;
|
|
p.x = X;
|
p.y = Y;
|
p.z = Z;
|
return Error_Code;
|
}, // cs_geodetic_to_geocentric()
|
|
|
geocentric_to_geodetic : function (p) {
|
/* local defintions and variables */
|
/* end-criterium of loop, accuracy of sin(Latitude) */
|
var genau = 1.E-12;
|
var genau2 = (genau*genau);
|
var maxiter = 30;
|
|
var P; /* distance between semi-minor axis and location */
|
var RR; /* distance between center and location */
|
var CT; /* sin of geocentric latitude */
|
var ST; /* cos of geocentric latitude */
|
var RX;
|
var RK;
|
var RN; /* Earth radius at location */
|
var CPHI0; /* cos of start or old geodetic latitude in iterations */
|
var SPHI0; /* sin of start or old geodetic latitude in iterations */
|
var CPHI; /* cos of searched geodetic latitude */
|
var SPHI; /* sin of searched geodetic latitude */
|
var SDPHI; /* end-criterium: addition-theorem of sin(Latitude(iter)-Latitude(iter-1)) */
|
var At_Pole; /* indicates location is in polar region */
|
var iter; /* # of continous iteration, max. 30 is always enough (s.a.) */
|
|
var X = p.x;
|
var Y = p.y;
|
var Z = p.z ? p.z : 0.0; //Z value not always supplied
|
var Longitude;
|
var Latitude;
|
var Height;
|
|
At_Pole = false;
|
P = Math.sqrt(X*X+Y*Y);
|
RR = Math.sqrt(X*X+Y*Y+Z*Z);
|
|
/* special cases for latitude and longitude */
|
if (P/this.a < genau) {
|
|
/* special case, if P=0. (X=0., Y=0.) */
|
At_Pole = true;
|
Longitude = 0.0;
|
|
/* if (X,Y,Z)=(0.,0.,0.) then Height becomes semi-minor axis
|
* of ellipsoid (=center of mass), Latitude becomes PI/2 */
|
if (RR/this.a < genau) {
|
Latitude = Proj4js.common.HALF_PI;
|
Height = -this.b;
|
return;
|
}
|
} else {
|
/* ellipsoidal (geodetic) longitude
|
* interval: -PI < Longitude <= +PI */
|
Longitude=Math.atan2(Y,X);
|
}
|
|
/* --------------------------------------------------------------
|
* Following iterative algorithm was developped by
|
* "Institut f�r Erdmessung", University of Hannover, July 1988.
|
* Internet: www.ife.uni-hannover.de
|
* Iterative computation of CPHI,SPHI and Height.
|
* Iteration of CPHI and SPHI to 10**-12 radian resp.
|
* 2*10**-7 arcsec.
|
* --------------------------------------------------------------
|
*/
|
CT = Z/RR;
|
ST = P/RR;
|
RX = 1.0/Math.sqrt(1.0-this.es*(2.0-this.es)*ST*ST);
|
CPHI0 = ST*(1.0-this.es)*RX;
|
SPHI0 = CT*RX;
|
iter = 0;
|
|
/* loop to find sin(Latitude) resp. Latitude
|
* until |sin(Latitude(iter)-Latitude(iter-1))| < genau */
|
do
|
{
|
iter++;
|
RN = this.a/Math.sqrt(1.0-this.es*SPHI0*SPHI0);
|
|
/* ellipsoidal (geodetic) height */
|
Height = P*CPHI0+Z*SPHI0-RN*(1.0-this.es*SPHI0*SPHI0);
|
|
RK = this.es*RN/(RN+Height);
|
RX = 1.0/Math.sqrt(1.0-RK*(2.0-RK)*ST*ST);
|
CPHI = ST*(1.0-RK)*RX;
|
SPHI = CT*RX;
|
SDPHI = SPHI*CPHI0-CPHI*SPHI0;
|
CPHI0 = CPHI;
|
SPHI0 = SPHI;
|
}
|
while (SDPHI*SDPHI > genau2 && iter < maxiter);
|
|
/* ellipsoidal (geodetic) latitude */
|
Latitude=Math.atan(SPHI/Math.abs(CPHI));
|
|
p.x = Longitude;
|
p.y = Latitude;
|
p.z = Height;
|
return p;
|
}, // cs_geocentric_to_geodetic()
|
|
/** Convert_Geocentric_To_Geodetic
|
* The method used here is derived from 'An Improved Algorithm for
|
* Geocentric to Geodetic Coordinate Conversion', by Ralph Toms, Feb 1996
|
*/
|
geocentric_to_geodetic_noniter : function (p) {
|
var X = p.x;
|
var Y = p.y;
|
var Z = p.z ? p.z : 0; //Z value not always supplied
|
var Longitude;
|
var Latitude;
|
var Height;
|
|
var W; /* distance from Z axis */
|
var W2; /* square of distance from Z axis */
|
var T0; /* initial estimate of vertical component */
|
var T1; /* corrected estimate of vertical component */
|
var S0; /* initial estimate of horizontal component */
|
var S1; /* corrected estimate of horizontal component */
|
var Sin_B0; /* Math.sin(B0), B0 is estimate of Bowring aux variable */
|
var Sin3_B0; /* cube of Math.sin(B0) */
|
var Cos_B0; /* Math.cos(B0) */
|
var Sin_p1; /* Math.sin(phi1), phi1 is estimated latitude */
|
var Cos_p1; /* Math.cos(phi1) */
|
var Rn; /* Earth radius at location */
|
var Sum; /* numerator of Math.cos(phi1) */
|
var At_Pole; /* indicates location is in polar region */
|
|
X = parseFloat(X); // cast from string to float
|
Y = parseFloat(Y);
|
Z = parseFloat(Z);
|
|
At_Pole = false;
|
if (X != 0.0)
|
{
|
Longitude = Math.atan2(Y,X);
|
}
|
else
|
{
|
if (Y > 0)
|
{
|
Longitude = Proj4js.common.HALF_PI;
|
}
|
else if (Y < 0)
|
{
|
Longitude = -Proj4js.common.HALF_PI;
|
}
|
else
|
{
|
At_Pole = true;
|
Longitude = 0.0;
|
if (Z > 0.0)
|
{ /* north pole */
|
Latitude = Proj4js.common.HALF_PI;
|
}
|
else if (Z < 0.0)
|
{ /* south pole */
|
Latitude = -Proj4js.common.HALF_PI;
|
}
|
else
|
{ /* center of earth */
|
Latitude = Proj4js.common.HALF_PI;
|
Height = -this.b;
|
return;
|
}
|
}
|
}
|
W2 = X*X + Y*Y;
|
W = Math.sqrt(W2);
|
T0 = Z * Proj4js.common.AD_C;
|
S0 = Math.sqrt(T0 * T0 + W2);
|
Sin_B0 = T0 / S0;
|
Cos_B0 = W / S0;
|
Sin3_B0 = Sin_B0 * Sin_B0 * Sin_B0;
|
T1 = Z + this.b * this.ep2 * Sin3_B0;
|
Sum = W - this.a * this.es * Cos_B0 * Cos_B0 * Cos_B0;
|
S1 = Math.sqrt(T1*T1 + Sum * Sum);
|
Sin_p1 = T1 / S1;
|
Cos_p1 = Sum / S1;
|
Rn = this.a / Math.sqrt(1.0 - this.es * Sin_p1 * Sin_p1);
|
if (Cos_p1 >= Proj4js.common.COS_67P5)
|
{
|
Height = W / Cos_p1 - Rn;
|
}
|
else if (Cos_p1 <= -Proj4js.common.COS_67P5)
|
{
|
Height = W / -Cos_p1 - Rn;
|
}
|
else
|
{
|
Height = Z / Sin_p1 + Rn * (this.es - 1.0);
|
}
|
if (At_Pole == false)
|
{
|
Latitude = Math.atan(Sin_p1 / Cos_p1);
|
}
|
|
p.x = Longitude;
|
p.y = Latitude;
|
p.z = Height;
|
return p;
|
}, // geocentric_to_geodetic_noniter()
|
|
/****************************************************************/
|
// pj_geocentic_to_wgs84( p )
|
// p = point to transform in geocentric coordinates (x,y,z)
|
geocentric_to_wgs84 : function ( p ) {
|
|
if( this.datum_type == Proj4js.common.PJD_3PARAM )
|
{
|
// if( x[io] == HUGE_VAL )
|
// continue;
|
p.x += this.datum_params[0];
|
p.y += this.datum_params[1];
|
p.z += this.datum_params[2];
|
|
}
|
else if (this.datum_type == Proj4js.common.PJD_7PARAM)
|
{
|
var Dx_BF =this.datum_params[0];
|
var Dy_BF =this.datum_params[1];
|
var Dz_BF =this.datum_params[2];
|
var Rx_BF =this.datum_params[3];
|
var Ry_BF =this.datum_params[4];
|
var Rz_BF =this.datum_params[5];
|
var M_BF =this.datum_params[6];
|
// if( x[io] == HUGE_VAL )
|
// continue;
|
var x_out = M_BF*( p.x - Rz_BF*p.y + Ry_BF*p.z) + Dx_BF;
|
var y_out = M_BF*( Rz_BF*p.x + p.y - Rx_BF*p.z) + Dy_BF;
|
var z_out = M_BF*(-Ry_BF*p.x + Rx_BF*p.y + p.z) + Dz_BF;
|
p.x = x_out;
|
p.y = y_out;
|
p.z = z_out;
|
}
|
}, // cs_geocentric_to_wgs84
|
|
/****************************************************************/
|
// pj_geocentic_from_wgs84()
|
// coordinate system definition,
|
// point to transform in geocentric coordinates (x,y,z)
|
geocentric_from_wgs84 : function( p ) {
|
|
if( this.datum_type == Proj4js.common.PJD_3PARAM )
|
{
|
//if( x[io] == HUGE_VAL )
|
// continue;
|
p.x -= this.datum_params[0];
|
p.y -= this.datum_params[1];
|
p.z -= this.datum_params[2];
|
|
}
|
else if (this.datum_type == Proj4js.common.PJD_7PARAM)
|
{
|
var Dx_BF =this.datum_params[0];
|
var Dy_BF =this.datum_params[1];
|
var Dz_BF =this.datum_params[2];
|
var Rx_BF =this.datum_params[3];
|
var Ry_BF =this.datum_params[4];
|
var Rz_BF =this.datum_params[5];
|
var M_BF =this.datum_params[6];
|
var x_tmp = (p.x - Dx_BF) / M_BF;
|
var y_tmp = (p.y - Dy_BF) / M_BF;
|
var z_tmp = (p.z - Dz_BF) / M_BF;
|
//if( x[io] == HUGE_VAL )
|
// continue;
|
|
p.x = x_tmp + Rz_BF*y_tmp - Ry_BF*z_tmp;
|
p.y = -Rz_BF*x_tmp + y_tmp + Rx_BF*z_tmp;
|
p.z = Ry_BF*x_tmp - Rx_BF*y_tmp + z_tmp;
|
} //cs_geocentric_from_wgs84()
|
}
|
});
|
|
/** point object, nothing fancy, just allows values to be
|
passed back and forth by reference rather than by value.
|
Other point classes may be used as long as they have
|
x and y properties, which will get modified in the transform method.
|
*/
|
Proj4js.Point = Proj4js.Class({
|
|
/**
|
* Constructor: Proj4js.Point
|
*
|
* Parameters:
|
* - x {float} or {Array} either the first coordinates component or
|
* the full coordinates
|
* - y {float} the second component
|
* - z {float} the third component, optional.
|
*/
|
initialize : function(x,y,z) {
|
if (typeof x == 'object') {
|
this.x = x[0];
|
this.y = x[1];
|
this.z = x[2] || 0.0;
|
} else if (typeof x == 'string' && typeof y == 'undefined') {
|
var coords = x.split(',');
|
this.x = parseFloat(coords[0]);
|
this.y = parseFloat(coords[1]);
|
this.z = parseFloat(coords[2]) || 0.0;
|
} else {
|
this.x = x;
|
this.y = y;
|
this.z = z || 0.0;
|
}
|
},
|
|
/**
|
* APIMethod: clone
|
* Build a copy of a Proj4js.Point object.
|
*
|
* Return:
|
* {Proj4js}.Point the cloned point.
|
*/
|
clone : function() {
|
return new Proj4js.Point(this.x, this.y, this.z);
|
},
|
|
/**
|
* APIMethod: toString
|
* Return a readable string version of the point
|
*
|
* Return:
|
* {String} String representation of Proj4js.Point object.
|
* (ex. <i>"x=5,y=42"</i>)
|
*/
|
toString : function() {
|
return ("x=" + this.x + ",y=" + this.y);
|
},
|
|
/**
|
* APIMethod: toShortString
|
* Return a short string version of the point.
|
*
|
* Return:
|
* {String} Shortened String representation of Proj4js.Point object.
|
* (ex. <i>"5, 42"</i>)
|
*/
|
toShortString : function() {
|
return (this.x + ", " + this.y);
|
}
|
});
|
|
Proj4js.PrimeMeridian = {
|
"greenwich": 0.0, //"0dE",
|
"lisbon": -9.131906111111, //"9d07'54.862\"W",
|
"paris": 2.337229166667, //"2d20'14.025\"E",
|
"bogota": -74.080916666667, //"74d04'51.3\"W",
|
"madrid": -3.687938888889, //"3d41'16.58\"W",
|
"rome": 12.452333333333, //"12d27'8.4\"E",
|
"bern": 7.439583333333, //"7d26'22.5\"E",
|
"jakarta": 106.807719444444, //"106d48'27.79\"E",
|
"ferro": -17.666666666667, //"17d40'W",
|
"brussels": 4.367975, //"4d22'4.71\"E",
|
"stockholm": 18.058277777778, //"18d3'29.8\"E",
|
"athens": 23.7163375, //"23d42'58.815\"E",
|
"oslo": 10.722916666667 //"10d43'22.5\"E"
|
};
|
|
Proj4js.Ellipsoid = {
|
"MERIT": {a:6378137.0, rf:298.257, ellipseName:"MERIT 1983"},
|
"SGS85": {a:6378136.0, rf:298.257, ellipseName:"Soviet Geodetic System 85"},
|
"GRS80": {a:6378137.0, rf:298.257222101, ellipseName:"GRS 1980(IUGG, 1980)"},
|
"IAU76": {a:6378140.0, rf:298.257, ellipseName:"IAU 1976"},
|
"airy": {a:6377563.396, b:6356256.910, ellipseName:"Airy 1830"},
|
"APL4.": {a:6378137, rf:298.25, ellipseName:"Appl. Physics. 1965"},
|
"NWL9D": {a:6378145.0, rf:298.25, ellipseName:"Naval Weapons Lab., 1965"},
|
"mod_airy": {a:6377340.189, b:6356034.446, ellipseName:"Modified Airy"},
|
"andrae": {a:6377104.43, rf:300.0, ellipseName:"Andrae 1876 (Den., Iclnd.)"},
|
"aust_SA": {a:6378160.0, rf:298.25, ellipseName:"Australian Natl & S. Amer. 1969"},
|
"GRS67": {a:6378160.0, rf:298.2471674270, ellipseName:"GRS 67(IUGG 1967)"},
|
"bessel": {a:6377397.155, rf:299.1528128, ellipseName:"Bessel 1841"},
|
"bess_nam": {a:6377483.865, rf:299.1528128, ellipseName:"Bessel 1841 (Namibia)"},
|
"clrk66": {a:6378206.4, b:6356583.8, ellipseName:"Clarke 1866"},
|
"clrk80": {a:6378249.145, rf:293.4663, ellipseName:"Clarke 1880 mod."},
|
"CPM": {a:6375738.7, rf:334.29, ellipseName:"Comm. des Poids et Mesures 1799"},
|
"delmbr": {a:6376428.0, rf:311.5, ellipseName:"Delambre 1810 (Belgium)"},
|
"engelis": {a:6378136.05, rf:298.2566, ellipseName:"Engelis 1985"},
|
"evrst30": {a:6377276.345, rf:300.8017, ellipseName:"Everest 1830"},
|
"evrst48": {a:6377304.063, rf:300.8017, ellipseName:"Everest 1948"},
|
"evrst56": {a:6377301.243, rf:300.8017, ellipseName:"Everest 1956"},
|
"evrst69": {a:6377295.664, rf:300.8017, ellipseName:"Everest 1969"},
|
"evrstSS": {a:6377298.556, rf:300.8017, ellipseName:"Everest (Sabah & Sarawak)"},
|
"fschr60": {a:6378166.0, rf:298.3, ellipseName:"Fischer (Mercury Datum) 1960"},
|
"fschr60m": {a:6378155.0, rf:298.3, ellipseName:"Fischer 1960"},
|
"fschr68": {a:6378150.0, rf:298.3, ellipseName:"Fischer 1968"},
|
"helmert": {a:6378200.0, rf:298.3, ellipseName:"Helmert 1906"},
|
"hough": {a:6378270.0, rf:297.0, ellipseName:"Hough"},
|
"intl": {a:6378388.0, rf:297.0, ellipseName:"International 1909 (Hayford)"},
|
"kaula": {a:6378163.0, rf:298.24, ellipseName:"Kaula 1961"},
|
"lerch": {a:6378139.0, rf:298.257, ellipseName:"Lerch 1979"},
|
"mprts": {a:6397300.0, rf:191.0, ellipseName:"Maupertius 1738"},
|
"new_intl": {a:6378157.5, b:6356772.2, ellipseName:"New International 1967"},
|
"plessis": {a:6376523.0, rf:6355863.0, ellipseName:"Plessis 1817 (France)"},
|
"krass": {a:6378245.0, rf:298.3, ellipseName:"Krassovsky, 1942"},
|
"SEasia": {a:6378155.0, b:6356773.3205, ellipseName:"Southeast Asia"},
|
"walbeck": {a:6376896.0, b:6355834.8467, ellipseName:"Walbeck"},
|
"WGS60": {a:6378165.0, rf:298.3, ellipseName:"WGS 60"},
|
"WGS66": {a:6378145.0, rf:298.25, ellipseName:"WGS 66"},
|
"WGS72": {a:6378135.0, rf:298.26, ellipseName:"WGS 72"},
|
"WGS84": {a:6378137.0, rf:298.257223563, ellipseName:"WGS 84"},
|
"sphere": {a:6370997.0, b:6370997.0, ellipseName:"Normal Sphere (r=6370997)"}
|
};
|
|
Proj4js.Datum = {
|
"WGS84": {towgs84: "0,0,0", ellipse: "WGS84", datumName: "WGS84"},
|
"GGRS87": {towgs84: "-199.87,74.79,246.62", ellipse: "GRS80", datumName: "Greek_Geodetic_Reference_System_1987"},
|
"NAD83": {towgs84: "0,0,0", ellipse: "GRS80", datumName: "North_American_Datum_1983"},
|
"NAD27": {nadgrids: "@conus,@alaska,@ntv2_0.gsb,@ntv1_can.dat", ellipse: "clrk66", datumName: "North_American_Datum_1927"},
|
"potsdam": {towgs84: "606.0,23.0,413.0", ellipse: "bessel", datumName: "Potsdam Rauenberg 1950 DHDN"},
|
"carthage": {towgs84: "-263.0,6.0,431.0", ellipse: "clark80", datumName: "Carthage 1934 Tunisia"},
|
"hermannskogel": {towgs84: "653.0,-212.0,449.0", ellipse: "bessel", datumName: "Hermannskogel"},
|
"ire65": {towgs84: "482.530,-130.596,564.557,-1.042,-0.214,-0.631,8.15", ellipse: "mod_airy", datumName: "Ireland 1965"},
|
"nzgd49": {towgs84: "59.47,-5.04,187.44,0.47,-0.1,1.024,-4.5993", ellipse: "intl", datumName: "New Zealand Geodetic Datum 1949"},
|
"OSGB36": {towgs84: "446.448,-125.157,542.060,0.1502,0.2470,0.8421,-20.4894", ellipse: "airy", datumName: "Airy 1830"}
|
};
|
|
Proj4js.WGS84 = new Proj4js.Proj('WGS84');
|
Proj4js.Datum['OSB36'] = Proj4js.Datum['OSGB36']; //as returned from spatialreference.org
|
|
//lookup table to go from the projection name in WKT to the Proj4js projection name
|
//build this out as required
|
Proj4js.wktProjections = {
|
"Lambert Tangential Conformal Conic Projection": "lcc",
|
"Mercator": "merc",
|
"Popular Visualisation Pseudo Mercator": "merc",
|
"Mercator_1SP": "merc",
|
"Transverse_Mercator": "tmerc",
|
"Transverse Mercator": "tmerc",
|
"Lambert Azimuthal Equal Area": "laea",
|
"Universal Transverse Mercator System": "utm"
|
};
|
