reprojection library
当前为
此脚本不应直接安装。它是供其他脚本使用的外部库，要使用该库请加入元指令 // @require https://update.cn-greasyfork.org/scripts/13097/80447/Proj4js.js
/*
Author: Mike Adair madairATdmsolutions.ca
Richard Greenwood [email protected]
License: MIT as per: ../LICENSE
$Id: Proj.js 2956 2007-07-09 12:17:52Z steven $
*/
/**
* Namespace: Proj4js
*
* Proj4js is a JavaScript library to transform point coordinates from one
* coordinate system to another, including datum transformations.
*
* This library is a port of both the Proj.4 and GCTCP C libraries to JavaScript.
* Enabling these transformations in the browser allows geographic data stored
* in different projections to be combined in browser-based web mapping
* applications.
*
* Proj4js must have access to coordinate system initialization strings (which
* are the same as for PROJ.4 command line). Thes can be included in your
* application using a <script> tag or Proj4js can load CS initialization
* strings from a local directory or a web service such as spatialreference.org.
*
* Similarly, Proj4js must have access to projection transform code. These can
* be included individually using a <script> tag in your page, built into a
* custom build of Proj4js or loaded dynamically at run-time. Using the
* -combined and -compressed versions of Proj4js includes all projection class
* code by default.
*
* Note that dynamic loading of defs and code happens ascynchrously, check the
* Proj.readyToUse flag before using the Proj object. If the defs and code
* required by your application are loaded through script tags, dynamic loading
* is not required and the Proj object will be readyToUse on return from the
* constructor.
*
* All coordinates are handled as points which have a .x and a .y property
* which will be modified in place.
*
* Override Proj4js.reportError for output of alerts and warnings.
*
* See http://trac.osgeo.org/proj4js/wiki/UserGuide for full details.
*/
/**
* Global namespace object for Proj4js library
*/
var Proj4js = {
/**
* Property: defaultDatum
* The datum to use when no others a specified
*/
defaultDatum: 'WGS84', //default datum
/**
* Method: transform(source, dest, point)
* Transform a point coordinate from one map projection to another. This is
* really the only public method you should need to use.
*
* Parameters:
* source - {Proj4js.Proj} source map projection for the transformation
* dest - {Proj4js.Proj} destination map projection for the transformation
* point - {Object} point to transform, may be geodetic (long, lat) or
* projected Cartesian (x,y), but should always have x,y properties.
*/
transform: function(source, dest, point) {
if (!source.readyToUse) {
this.reportError("Proj4js initialization for:"+source.srsCode+" not yet complete");
return point;
}
if (!dest.readyToUse) {
this.reportError("Proj4js initialization for:"+dest.srsCode+" not yet complete");
return point;
}
// Workaround for datum shifts towgs84, if either source or destination projection is not wgs84
if (source.datum && dest.datum && (
((source.datum.datum_type == Proj4js.common.PJD_3PARAM || source.datum.datum_type == Proj4js.common.PJD_7PARAM) && dest.datumCode != "WGS84") ||
((dest.datum.datum_type == Proj4js.common.PJD_3PARAM || dest.datum.datum_type == Proj4js.common.PJD_7PARAM) && source.datumCode != "WGS84"))) {
var wgs84 = Proj4js.WGS84;
this.transform(source, wgs84, point);
source = wgs84;
}
// DGR, 2010/11/12
if (source.axis!="enu") {
this.adjust_axis(source,false,point);
}
// Transform source points to long/lat, if they aren't already.
if (source.projName=="longlat") {
point.x *= Proj4js.common.D2R; // convert degrees to radians
point.y *= Proj4js.common.D2R;
} else {
if (source.to_meter) {
point.x *= source.to_meter;
point.y *= source.to_meter;
}
source.inverse(point); // Convert Cartesian to longlat
}
// Adjust for the prime meridian if necessary
if (source.from_greenwich) {
point.x += source.from_greenwich;
}
// Convert datums if needed, and if possible.
point = this.datum_transform( source.datum, dest.datum, point );
// Adjust for the prime meridian if necessary
if (dest.from_greenwich) {
point.x -= dest.from_greenwich;
}
if (dest.projName=="longlat") {
// convert radians to decimal degrees
point.x *= Proj4js.common.R2D;
point.y *= Proj4js.common.R2D;
} else { // else project
dest.forward(point);
if (dest.to_meter) {
point.x /= dest.to_meter;
point.y /= dest.to_meter;
}
}
// DGR, 2010/11/12
if (dest.axis!="enu") {
this.adjust_axis(dest,true,point);
}
return point;
}, // transform()
/** datum_transform()
source coordinate system definition,
destination coordinate system definition,
point to transform in geodetic coordinates (long, lat, height)
*/
datum_transform : function( source, dest, point ) {
// Short cut if the datums are identical.
if( source.compare_datums( dest ) ) {
return point; // in this case, zero is sucess,
// whereas cs_compare_datums returns 1 to indicate TRUE
// confusing, should fix this
}
// Explicitly skip datum transform by setting 'datum=none' as parameter for either source or dest
if( source.datum_type == Proj4js.common.PJD_NODATUM
|| dest.datum_type == Proj4js.common.PJD_NODATUM) {
return point;
}
//DGR: 2012-07-29 : add nadgrids support (begin)
var src_a = source.a;
var src_es = source.es;
var dst_a = dest.a;
var dst_es = dest.es;
var fallback= source.datum_type;
// If this datum requires grid shifts, then apply it to geodetic coordinates.
if( fallback == Proj4js.common.PJD_GRIDSHIFT )
{
if (this.apply_gridshift( source, 0, point )==0) {
source.a = Proj4js.common.SRS_WGS84_SEMIMAJOR;
source.es = Proj4js.common.SRS_WGS84_ESQUARED;
} else {
// try 3 or 7 params transformation or nothing ?
if (!source.datum_params) {
source.a = src_a;
source.es = source.es;
return point;
}
var wp= 1.0;
for (var i= 0, l= source.datum_params.length; i<l; i++) {
wp*= source.datum_params[i];
}
if (wp==0.0) {
source.a = src_a;
source.es = source.es;
return point;
}
fallback= source.datum_params.length>3?
Proj4js.common.PJD_7PARAM
: Proj4js.common.PJD_3PARAM;
// CHECK_RETURN;
}
}
if( dest.datum_type == Proj4js.common.PJD_GRIDSHIFT )
{
dest.a = Proj4js.common.SRS_WGS84_SEMIMAJOR;
dest.es = Proj4js.common.SRS_WGS84_ESQUARED;
}
// Do we need to go through geocentric coordinates?
if (source.es != dest.es || source.a != dest.a
|| fallback == Proj4js.common.PJD_3PARAM
|| fallback == Proj4js.common.PJD_7PARAM
|| dest.datum_type == Proj4js.common.PJD_3PARAM
|| dest.datum_type == Proj4js.common.PJD_7PARAM)
{
//DGR: 2012-07-29 : add nadgrids support (end)
// Convert to geocentric coordinates.
source.geodetic_to_geocentric( point );
// CHECK_RETURN;
// Convert between datums
if( source.datum_type == Proj4js.common.PJD_3PARAM || source.datum_type == Proj4js.common.PJD_7PARAM ) {
source.geocentric_to_wgs84(point);
// CHECK_RETURN;
}
if( dest.datum_type == Proj4js.common.PJD_3PARAM || dest.datum_type == Proj4js.common.PJD_7PARAM ) {
dest.geocentric_from_wgs84(point);
// CHECK_RETURN;
}
// Convert back to geodetic coordinates
dest.geocentric_to_geodetic( point );
// CHECK_RETURN;
}
// Apply grid shift to destination if required
if( dest.datum_type == Proj4js.common.PJD_GRIDSHIFT )
{
this.apply_gridshift( dest, 1, point);
// CHECK_RETURN;
}
source.a = src_a;
source.es = src_es;
dest.a = dst_a;
dest.es = dst_es;
return point;
}, // cs_datum_transform
/**
* This is the real workhorse, given a gridlist
* DGR: 2012-07-29 addition based on proj4 trunk
*/
apply_gridshift : function(srs,inverse,point) {
if (srs.grids==null || srs.grids.length==0) {
return -38;
}
var input= {"x":point.x, "y":point.y};
var output= {"x":Number.NaN, "y":Number.NaN};
/* keep trying till we find a table that works */
var onlyMandatoryGrids= false;
for (var i= 0, l= srs.grids.length; i<l; i++) {
var gi= srs.grids[i];
onlyMandatoryGrids= gi.mandatory;
var ct= gi.grid;
if (ct==null) {
if (gi.mandatory) {
this.reportError("unable to find '"+gi.name+"' grid.");
return -48;
}
continue;//optional grid
}
/* skip tables that don't match our point at all. */
var epsilon= (Math.abs(ct.del[1])+Math.abs(ct.del[0]))/10000.0;
if( ct.ll[1]-epsilon>input.y || ct.ll[0]-epsilon>input.x ||
ct.ll[1]+(ct.lim[1]-1)*ct.del[1]+epsilon<input.y ||
ct.ll[0]+(ct.lim[0]-1)*ct.del[0]+epsilon<input.x ) {
continue;
}
/* If we have child nodes, check to see if any of them apply. */
/* TODO : only plain grid has been implemented ... */
/* we found a more refined child node to use */
/* load the grid shift info if we don't have it. */
/* TODO : Proj4js.grids pre-loaded (as they can be huge ...) */
/* skip numerical computing error when "null" grid (identity grid): */
if (gi.name=="null") {
output.x= input.x;
output.y= input.y;
} else {
output= Proj4js.common.nad_cvt(input, inverse, ct);
}
if (!isNaN(output.x)) {
break;
}
}
if (isNaN(output.x)) {
if (!onlyMandatoryGrids) {
this.reportError("failed to find a grid shift table for location '"+
input.x*Proj4js.common.R2D+" "+input.y*Proj4js.common.R2D+
" tried: '"+srs.nadgrids+"'");
return -48;
}
return -1;//FIXME: no shift applied ...
}
point.x= output.x;
point.y= output.y;
return 0;
},
/**
* Function: adjust_axis
* Normalize or de-normalized the x/y/z axes. The normal form is "enu"
* (easting, northing, up).
* Parameters:
* crs {Proj4js.Proj} the coordinate reference system
* denorm {Boolean} when false, normalize
* point {Object} the coordinates to adjust
*/
adjust_axis: function(crs, denorm, point) {
var xin= point.x, yin= point.y, zin= point.z || 0.0;
var v, t;
for (var i= 0; i<3; i++) {
if (denorm && i==2 && point.z===undefined) { continue; }
if (i==0) { v= xin; t= 'x'; }
else if (i==1) { v= yin; t= 'y'; }
else { v= zin; t= 'z'; }
switch(crs.axis[i]) {
case 'e':
point[t]= v;
break;
case 'w':
point[t]= -v;
break;
case 'n':
point[t]= v;
break;
case 's':
point[t]= -v;
break;
case 'u':
if (point[t]!==undefined) { point.z= v; }
break;
case 'd':
if (point[t]!==undefined) { point.z= -v; }
break;
default :
alert("ERROR: unknow axis ("+crs.axis[i]+") - check definition of "+crs.projName);
return null;
}
}
return point;
},
/**
* Function: reportError
* An internal method to report errors back to user.
* Override this in applications to report error messages or throw exceptions.
*/
reportError: function(msg) {
//console.log(msg);
},
/**
*
* Title: Private Methods
* The following properties and methods are intended for internal use only.
*
* This is a minimal implementation of JavaScript inheritance methods so that
* Proj4js can be used as a stand-alone library.
* These are copies of the equivalent OpenLayers methods at v2.7
*/
/**
* Function: extend
* Copy all properties of a source object to a destination object. Modifies
* the passed in destination object. Any properties on the source object
* that are set to undefined will not be (re)set on the destination object.
*
* Parameters:
* destination - {Object} The object that will be modified
* source - {Object} The object with properties to be set on the destination
*
* Returns:
* {Object} The destination object.
*/
extend: function(destination, source) {
destination = destination || {};
if(source) {
for(var property in source) {
var value = source[property];
if(value !== undefined) {
destination[property] = value;
}
}
}
return destination;
},
/**
* Constructor: Class
* Base class used to construct all other classes. Includes support for
* multiple inheritance.
*
*/
Class: function() {
var Class = function() {
this.initialize.apply(this, arguments);
};
var extended = {};
var parent;
for(var i=0; i<arguments.length; ++i) {
if(typeof arguments[i] == "function") {
// get the prototype of the superclass
parent = arguments[i].prototype;
} else {
// in this case we're extending with the prototype
parent = arguments[i];
}
Proj4js.extend(extended, parent);
}
Class.prototype = extended;
return Class;
},
/**
* Function: bind
* Bind a function to an object. Method to easily create closures with
* 'this' altered.
*
* Parameters:
* func - {Function} Input function.
* object - {Object} The object to bind to the input function (as this).
*
* Returns:
* {Function} A closure with 'this' set to the passed in object.
*/
bind: function(func, object) {
// create a reference to all arguments past the second one
var args = Array.prototype.slice.apply(arguments, [2]);
return function() {
// Push on any additional arguments from the actual function call.
// These will come after those sent to the bind call.
var newArgs = args.concat(
Array.prototype.slice.apply(arguments, [0])
);
return func.apply(object, newArgs);
};
},
/**
* The following properties and methods handle dynamic loading of JSON objects.
*/
/**
* Property: scriptName
* {String} The filename of this script without any path.
*/
scriptName: "proj4js.js",
/**
* Property: defsLookupService
* AJAX service to retreive projection definition parameters from
*/
defsLookupService: 'http://spatialreference.org/ref',
/**
* Property: libPath
* internal: http server path to library code.
*/
libPath: null,
/**
* Function: getScriptLocation
* Return the path to this script.
*
* Returns:
* Path to this script
*/
getScriptLocation: function () {
if (this.libPath) return this.libPath;
var scriptName = this.scriptName;
var scriptNameLen = scriptName.length;
var scripts = document.getElementsByTagName('script');
for (var i = 0; i < scripts.length; i++) {
var src = scripts[i].getAttribute('src');
if (src) {
var index = src.lastIndexOf(scriptName);
// is it found, at the end of the URL?
if ((index > -1) && (index + scriptNameLen == src.length)) {
this.libPath = src.slice(0, -scriptNameLen);
break;
}
}
}
return this.libPath||"";
},
/**
* Function: loadScript
* Load a JS file from a URL into a <script> tag in the page.
*
* Parameters:
* url - {String} The URL containing the script to load
* onload - {Function} A method to be executed when the script loads successfully
* onfail - {Function} A method to be executed when there is an error loading the script
* loadCheck - {Function} A boolean method that checks to see if the script
* has loaded. Typically this just checks for the existance of
* an object in the file just loaded.
*/
loadScript: function(url, onload, onfail, loadCheck) {
var script = document.createElement('script');
script.defer = false;
script.type = "text/javascript";
script.id = url;
script.onload = onload;
script.onerror = onfail;
script.loadCheck = loadCheck;
if (/MSIE/.test(navigator.userAgent)) {
script.onreadystatechange = this.checkReadyState;
}
document.getElementsByTagName('head')[0].appendChild(script);
script.src = url;
},
/**
* Function: checkReadyState
* IE workaround since there is no onerror handler. Calls the user defined
* loadCheck method to determine if the script is loaded.
*
*/
checkReadyState: function() {
if (this.readyState == 'loaded') {
if (!this.loadCheck()) {
this.onerror();
} else {
this.onload();
}
}
}
};
/**
* Class: Proj4js.Proj
*
* Proj objects provide transformation methods for point coordinates
* between geodetic latitude/longitude and a projected coordinate system.
* once they have been initialized with a projection code.
*
* Initialization of Proj objects is with a projection code, usually EPSG codes,
* which is the key that will be used with the Proj4js.defs array.
*
* The code passed in will be stripped of colons and converted to uppercase
* to locate projection definition files.
*
* A projection object has properties for units and title strings.
*/
Proj4js.Proj = Proj4js.Class({
/**
* Property: readyToUse
* Flag to indicate if initialization is complete for this Proj object
*/
readyToUse: false,
/**
* Property: title
* The title to describe the projection
*/
title: null,
/**
* Property: projName
* The projection class for this projection, e.g. lcc (lambert conformal conic,
* or merc for mercator). These are exactly equivalent to their Proj4
* counterparts.
*/
projName: null,
/**
* Property: units
* The units of the projection. Values include 'm' and 'degrees'
*/
units: null,
/**
* Property: datum
* The datum specified for the projection
*/
datum: null,
/**
* Property: x0
* The x coordinate origin
*/
x0: 0,
/**
* Property: y0
* The y coordinate origin
*/
y0: 0,
/**
* Property: localCS
* Flag to indicate if the projection is a local one in which no transforms
* are required.
*/
localCS: false,
/**
* Property: queue
* Buffer (FIFO) to hold callbacks waiting to be called when projection loaded.
*/
queue: null,
/**
* Constructor: initialize
* Constructor for Proj4js.Proj objects
*
* Parameters:
* srsCode - a code for map projection definition parameters. These are usually
* (but not always) EPSG codes.
*/
initialize: function(srsCode, callback) {
this.srsCodeInput = srsCode;
//Register callbacks prior to attempting to process definition
this.queue = [];
if( callback ){
this.queue.push( callback );
}
//check to see if this is a WKT string
if ((srsCode.indexOf('GEOGCS') >= 0) ||
(srsCode.indexOf('GEOCCS') >= 0) ||
(srsCode.indexOf('PROJCS') >= 0) ||
(srsCode.indexOf('LOCAL_CS') >= 0)) {
this.parseWKT(srsCode);
this.deriveConstants();
this.loadProjCode(this.projName);
return;
}
// DGR 2008-08-03 : support urn and url
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];
} else if (url[0].indexOf('/def/crs/')!=-1) {
// http://www.opengis.net/def/crs/EPSG/0/code
url= srsCode.split('/');
srsCode = url.pop();//code
url.pop();//version FIXME
srsCode = url.pop()+':'+srsCode;//authority
}
}
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() {
var re= new RegExp('(title|proj|units|datum|nadgrids|'+
'ellps|a|b|rf|'+
'lat_0|lat_1|lat_2|lat_ts|lon_0|lon_1|lon_2|alpha|lonc|'+
'x_0|y_0|k_0|k|r_a|zone|south|'+
'towgs84|to_meter|from_greenwich|pm|axis|czech|'+
'wktext|no_rot|no_off|no_defs)');
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
// DGR 2012-10-13 : + in title (EPSG:2056: CH1903+ / LV95)
case "title": this.title = paramVal;
while (!paramArray[prop+1].match(re)) {
this.title+= '+'+paramArray[++prop];
}
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;
// DGR 2011-03-20 : nagrids -> nadgrids
case "nadgrids": this.nadgrids = paramVal.replace(/\s/gi,""); break;// DGR 2012-07-29
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 "lon_1": this.long1 = paramVal*Proj4js.common.D2R; break;
case "lon_2": this.long2 = paramVal*Proj4js.common.D2R; break;
case "no_rot": this.no_rot = true; break;
case "no_off": this.no_off = true; break;
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;
case "czech": this.czech = true; 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 "wktext": break;//DGR 2012-07-29
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() {
// DGR 2011-03-20 : nagrids -> nadgrids
if (this.nadgrids && this.nadgrids.length==0) {
this.nadgrids= null;
}
if (this.nadgrids) {
this.grids= this.nadgrids.split(",");
var g= null, l= this.grids.length;
if (l>0) {
for (var i= 0; i<l; i++) {
g= this.grids[i];
var fg= g.split("@");
if (fg[fg.length-1]=="") {
Proj4js.reportError("nadgrids syntax error '"+this.nadgrids+"' : empty grid found");
continue;
}
this.grids[i]= {
mandatory: fg.length==1,//@=> optional grid (no error if not found)
name:fg[fg.length-1],
grid: Proj4js.grids[fg[fg.length-1]]//FIXME: grids loading ...
};
if (this.grids[i].mandatory && !this.grids[i].grid) {
Proj4js.reportError("Missing '"+this.grids[i].name+"'");
}
}
}
// DGR, 2011-03-20: grids is an array of objects that hold
// the loaded grids, its name and the mandatory informations of it.
}
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=WGS 84 (long/lat) +proj=longlat +ellps=WGS84 +datum=WGS84 +units=degrees",
'EPSG:4326': "+title=WGS 84 (long/lat) +proj=longlat +ellps=WGS84 +datum=WGS84 +units=degrees",
'EPSG:4269': "+title=NAD83 (long/lat) +proj=longlat +a=6378137.0 +b=6356752.31414036 +ellps=GRS80 +datum=NAD83 +units=degrees",
'EPSG:3857': "+title=WGS 84 / Pseudo-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:3857']; //maintain backward compat, official code is 3857
Proj4js.defs['GOOGLE'] = Proj4js.defs['EPSG:3857'];
Proj4js.defs['EPSG:900913'] = Proj4js.defs['EPSG:3857'];
Proj4js.defs['EPSG:102113'] = Proj4js.defs['EPSG:3857'];
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
SRS_WGS84_ESQUARED : 0.006694379990141316, //DGR: 2012-07-29
// 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 compute the inverse of qsfnz
------------------------------------------------------------*/
iqsfnz : function (eccent, q) {
var temp = 1.0-(1.0-eccent*eccent)/(2.0*eccent)*Math.log((1-eccent)/(1+eccent));
if (Math.abs(Math.abs(q)-temp)<1.0E-6) {
if (q<0.0) {
return (-1.0*Proj4js.common.HALF_PI);
} else {
return Proj4js.common.HALF_PI;
}
}
//var phi = 0.5* q/(1-eccent*eccent);
var phi = Math.asin(0.5*q);
var dphi;
var sin_phi;
var cos_phi;
var con;
for (var i=0;i<30;i++){
sin_phi = Math.sin(phi);
cos_phi = Math.cos(phi);
con = eccent*sin_phi;
dphi=Math.pow(1.0-con*con,2.0)/(2.0*cos_phi)*(q/(1-eccent*eccent)-sin_phi/(1.0-con*con)+0.5/eccent*Math.log((1.0-con)/(1.0+con)));
phi+=dphi;
if (Math.abs(dphi) <= .0000000001) {
return phi;
}
}
alert("IQSFN-CONV:Latitude failed to converge after 30 iterations");
return (NaN);
},
/* 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));},
imlfn : function(ml, e0, e1, e2, e3) {
var phi;
var dphi;
phi=ml/e0;
for (var i=0;i<15;i++){
dphi=(ml-(e0*phi-e1*Math.sin(2.0*phi)+e2*Math.sin(4.0*phi)-e3*Math.sin(6.0*phi)))/(e0-2.0*e1*Math.cos(2.0*phi)+4.0*e2*Math.cos(4.0*phi)-6.0*e3*Math.cos(6.0*phi));
phi+=dphi;
if (Math.abs(dphi) <= .0000000001) {
return phi;
}
}
Proj4js.reportError("IMLFN-CONV:Latitude failed to converge after 15 iterations");
return NaN;
},
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 ([email protected])
// 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;
},
/**
* Determine correction values
* source: nad_intr.c (DGR: 2012-07-29)
*/
nad_intr: function(pin,ct) {
// force computation by decreasing by 1e-7 to be as closed as possible
// from computation under C:C++ by leveraging rounding problems ...
var t= {"x":(pin.x-1.e-7)/ct.del[0],"y":(pin.y-1e-7)/ct.del[1]};
var indx= {"x":Math.floor(t.x),"y":Math.floor(t.y)};
var frct= {"x":t.x-1.0*indx.x,"y":t.y-1.0*indx.y};
var val= {"x":Number.NaN,"y":Number.NaN};
var inx;
if (indx.x<0) {
if (!(indx.x==-1 && frct.x>0.99999999999)) {
return val;
}
++indx.x;
frct.x= 0.0;
} else {
inx= indx.x+1;
if (inx>=ct.lim[0]) {
if (!(inx==ct.lim[0] && frct.x<1e-11)) {
return val;
}
--indx.x;
frct.x= 1.0;
}
}
if (indx.y<0) {
if (!(indx.y==-1 && frct.y>0.99999999999)) {
return val;
}
++indx.y;
frct.y= 0.0;
} else {
inx= indx.y+1;
if (inx>=ct.lim[1]) {
if (!(inx==ct.lim[1] && frct.y<1e-11)) {
return val;
}
--indx.y;
frct.y= 1.0;
}
}
inx= (indx.y*ct.lim[0])+indx.x;
var f00= {"x":ct.cvs[inx][0], "y":ct.cvs[inx][1]};
inx++;
var f10= {"x":ct.cvs[inx][0], "y":ct.cvs[inx][1]};
inx+= ct.lim[0];
var f11= {"x":ct.cvs[inx][0], "y":ct.cvs[inx][1]};
inx--;
var f01= {"x":ct.cvs[inx][0], "y":ct.cvs[inx][1]};
var m11= frct.x*frct.y, m10= frct.x*(1.0-frct.y),
m00= (1.0-frct.x)*(1.0-frct.y), m01= (1.0-frct.x)*frct.y;
val.x= (m00*f00.x + m10*f10.x + m01*f01.x + m11*f11.x);
val.y= (m00*f00.y + m10*f10.y + m01*f01.y + m11*f11.y);
return val;
},
/**
* Correct value
* source: nad_cvt.c (DGR: 2012-07-29)
*/
nad_cvt: function(pin,inverse,ct) {
var val= {"x":Number.NaN, "y":Number.NaN};
if (isNaN(pin.x)) { return val; }
var tb= {"x":pin.x, "y":pin.y};
tb.x-= ct.ll[0];
tb.y-= ct.ll[1];
tb.x= Proj4js.common.adjust_lon(tb.x - Proj4js.common.PI) + Proj4js.common.PI;
var t= Proj4js.common.nad_intr(tb,ct);
if (inverse) {
if (isNaN(t.x)) {
return val;
}
t.x= tb.x + t.x;
t.y= tb.y - t.y;
var i= 9, tol= 1e-12;
var dif, del;
do {
del= Proj4js.common.nad_intr(t,ct);
if (isNaN(del.x)) {
this.reportError("Inverse grid shift iteration failed, presumably at grid edge. Using first approximation.");
break;
}
dif= {"x":t.x-del.x-tb.x, "y":t.y+del.y-tb.y};
t.x-= dif.x;
t.y-= dif.y;
} while (i-- && Math.abs(dif.x)>tol && Math.abs(dif.y)>tol);
if (i<0) {
this.reportError("Inverse grid shift iterator failed to converge.");
return val;
}
val.x= Proj4js.common.adjust_lon(t.x+ct.ll[0]);
val.y= t.y+ct.ll[1];
} else {
if (!isNaN(t.x)) {
val.x= pin.x - t.x;
val.y= pin.y + t.y;
}
}
return val;
},
/* 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) { return; }
if (proj.datumCode && proj.datumCode == 'none') {
this.datum_type = Proj4js.common.PJD_NODATUM;
}
if (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;
}
}
}
// DGR 2011-03-21 : nadgrids support
this.datum_type = proj.grids?
Proj4js.common.PJD_GRIDSHIFT
: this.datum_type;
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;
if (this.datum_type==Proj4js.common.PJD_GRIDSHIFT) {
this.grids= proj.grids;
}
},
/****************************************************************/
// 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
//DGR 2012-07-29 lazy ...
return this.nadgrids == dest.nadgrids;
} 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"
};
// Based on proj4 CTABLE structure :
// FIXME: better to have array instead of object holding longitudes, latitudes members
// In the former case, one has to document index 0 is longitude and
// 1 is latitude ...
// In the later case, grid object gets bigger !!!!
// Solution 1 is chosen based on pj_gridinfo.c
Proj4js.grids= {
"null":{ // name of grid's file
"ll": [-3.14159265, -1.57079633], // lower-left coordinates in radians (longitude, latitude):
"del":[ 3.14159265, 1.57079633], // cell's size in radians (longitude, latitude):
"lim":[ 3, 3], // number of nodes in longitude, latitude (including edges):
"count":9, // total number of nodes
"cvs":[ // shifts : in ntv2 reverse order : lon, lat in radians ...
[0.0, 0.0], [0.0, 0.0], [0.0, 0.0], // for (lon= 0; lon<lim[0]; lon++) {
[0.0, 0.0], [0.0, 0.0], [0.0, 0.0], // for (lat= 0; lat<lim[1]; lat++) { p= cvs[lat*lim[0]+lon]; }
[0.0, 0.0], [0.0, 0.0], [0.0, 0.0] // }
]
}
};