Commit b29ecca9 authored by Calvin Metcalf's avatar Calvin Metcalf
Browse files

break up proj proccess

parent 374b9868

lib/Proj.js

+22 −130
Original line number Diff line number Diff line 
var parseCode = require("./parseCode");

var extend = require('./extend');

var defs = require('./defs');

var constants = {};

constants.grids = require('./constants/grids');

constants.Datum = require('./constants/Datum');

constants.Ellipsoid = require('./constants/Ellipsoid');

var datum = require('./datum');

var projections = require('./projections');

var wkt = require('./wkt');

var projStr = require('./projString');

var EPSLN = 1.0e-10;

// ellipoid pj_set_ell.c

var SIXTH = 0.1666666666666666667;

/* 1/6 */

var RA4 = 0.04722222222222222222;

/* 17/360 */

var RA6 = 0.02215608465608465608;

function Projection(srsCode) {

var deriveConstants = require('./deriveConstants');



function Projection(srsCode,callback) {

  if (!(this instanceof Projection)) {

    return new Projection(srsCode);

  }

  this.srsCodeInput = srsCode;

  this.x0 = 0;

  this.y0 = 0;

  var obj;

  if (typeof srsCode === 'string') {

    //check to see if this is a WKT string

    if (srsCode in defs) {

      this.deriveConstants(defs[srsCode]);

      extend(this, defs[srsCode]);

    }

    else if ((srsCode.indexOf('GEOGCS') >= 0) || (srsCode.indexOf('GEOCCS') >= 0) || (srsCode.indexOf('PROJCS') >= 0) || (srsCode.indexOf('LOCAL_CS') >= 0)) {

      obj = wkt(srsCode);

      this.deriveConstants(obj);

      extend(this, obj);

      //this.loadProjCode(this.projName);

    }

    else if (srsCode[0] === '+') {

      obj = projStr(srsCode);

      this.deriveConstants(obj);

      extend(this, obj);

    }

  callback = callback || function(error){

    if(error){

      throw error;

    }

  else {

    this.deriveConstants(srsCode);

    extend(this, srsCode);

  }



  this.initTransforms(this.projName);

  };

  var json = parseCode(srsCode);

  if(typeof json !== 'object'){

    callback(srsCode);

    return;

  }

Projection.projections = projections;

Projection.projections.start();

Projection.prototype = {

  /**

   * Function: initTransforms

   *    Finalize the initialization of the Proj object

   *

   */

  initTransforms: function(projName) {

    var ourProj = Projection.projections.get(projName);

  var modifiedJSON = deriveConstants(json);

  var ourProj = Projection.projections.get(modifiedJSON.projName);

  if(ourProj){

    extend(this, modifiedJSON);

    extend(this, ourProj);

    this.init();

    }

    else {

      throw ("unknown projection " + projName);

    }

  },



  deriveConstants: function(self) {

    // DGR 2011-03-20 : nagrids -> nadgrids

    if (self.nadgrids && self.nadgrids.length === 0) {

      self.nadgrids = null;

    }

    if (self.nadgrids) {

      self.grids = self.nadgrids.split(",");

      var g = null,

        l = self.grids.length;

      if (l > 0) {

        for (var i = 0; i < l; i++) {

          g = self.grids[i];

          var fg = g.split("@");

          if (fg[fg.length - 1] === "") {

            //..reportError("nadgrids syntax error '" + self.nadgrids + "' : empty grid found");

            continue;

          }

          self.grids[i] = {

            mandatory: fg.length === 1, //@=> optional grid (no error if not found)

            name: fg[fg.length - 1],

            grid: constants.grids[fg[fg.length - 1]] //FIXME: grids loading ...

          };

          if (self.grids[i].mandatory && !self.grids[i].grid) {

            //..reportError("Missing '" + self.grids[i].name + "'");

    callback(null, this);

  }else{

    callback(srsCode);

  }

}

      }

      // DGR, 2011-03-20: grids is an array of objects that hold

      // the loaded grids, its name and the mandatory informations of it.

    }

    if (self.datumCode && self.datumCode !== 'none') {

      var datumDef = constants.Datum[self.datumCode];

      if (datumDef) {

        self.datum_params = datumDef.towgs84 ? datumDef.towgs84.split(',') : null;

        self.ellps = datumDef.ellipse;

        self.datumName = datumDef.datumName ? datumDef.datumName : self.datumCode;

      }

    }

    if (!self.a) { // do we have an ellipsoid?

      var ellipse = constants.Ellipsoid[self.ellps] ? constants.Ellipsoid[self.ellps] : constants.Ellipsoid.WGS84;

      extend(self, ellipse);

    }

    if (self.rf && !self.b) {

      self.b = (1.0 - 1.0 / self.rf) * self.a;

    }

    if (self.rf === 0 || Math.abs(self.a - self.b) < EPSLN) {

      self.sphere = true;

      self.b = self.a;

    }

    self.a2 = self.a * self.a; // used in geocentric

    self.b2 = self.b * self.b; // used in geocentric

    self.es = (self.a2 - self.b2) / self.a2; // e ^ 2

    self.e = Math.sqrt(self.es); // eccentricity

    if (self.R_A) {

      self.a *= 1 - self.es * (SIXTH + self.es * (RA4 + self.es * RA6));

      self.a2 = self.a * self.a;

      self.b2 = self.b * self.b;

      self.es = 0;

    }

    self.ep2 = (self.a2 - self.b2) / self.b2; // used in geocentric

    if (!self.k0) {

      self.k0 = 1.0; //default value

    }

    //DGR 2010-11-12: axis

    if (!self.axis) {

      self.axis = "enu";

    }



    self.datum = datum(self);

  }

};

Projection.projections = projections;

Projection.projections.start();

module.exports = Projection;

lib/deriveConstants.js

0 → 100644
+54 −0
Original line number Diff line number Diff line 
var Datum = require('./constants/Datum');

var Ellipsoid = require('./constants/Ellipsoid');

var extend = require('./extend');

var datum = require('./datum');

var EPSLN = 1.0e-10;

// ellipoid pj_set_ell.c

var SIXTH = 0.1666666666666666667;

/* 1/6 */

var RA4 = 0.04722222222222222222;

/* 17/360 */

var RA6 = 0.02215608465608465608;

module.exports = function(json) {

  // DGR 2011-03-20 : nagrids -> nadgrids

  if (json.datumCode && json.datumCode !== 'none') {

    var datumDef = Datum[json.datumCode];

    if (datumDef) {

      json.datum_params = datumDef.towgs84 ? datumDef.towgs84.split(',') : null;

      json.ellps = datumDef.ellipse;

      json.datumName = datumDef.datumName ? datumDef.datumName : json.datumCode;

    }

  }

  if (!json.a) { // do we have an ellipsoid?

    var ellipse = Ellipsoid[json.ellps] ? Ellipsoid[json.ellps] : Ellipsoid.WGS84;

    extend(json, ellipse);

  }

  if (json.rf && !json.b) {

    json.b = (1.0 - 1.0 / json.rf) * json.a;

  }

  if (json.rf === 0 || Math.abs(json.a - json.b) < EPSLN) {

    json.sphere = true;

    json.b = json.a;

  }

  json.a2 = json.a * json.a; // used in geocentric

  json.b2 = json.b * json.b; // used in geocentric

  json.es = (json.a2 - json.b2) / json.a2; // e ^ 2

  json.e = Math.sqrt(json.es); // eccentricity

  if (json.R_A) {

    json.a *= 1 - json.es * (SIXTH + json.es * (RA4 + json.es * RA6));

    json.a2 = json.a * json.a;

    json.b2 = json.b * json.b;

    json.es = 0;

  }

  json.ep2 = (json.a2 - json.b2) / json.b2; // used in geocentric

  if (!json.k0) {

    json.k0 = 1.0; //default value

  }

  //DGR 2010-11-12: axis

  if (!json.axis) {

    json.axis = "enu";

  }



  json.datum = datum(json);

  return json;

};
 
 No newline at end of file

lib/parseCode.js

0 → 100644
+36 −0
Original line number Diff line number Diff line 
var defs = require('./defs');

var wkt = require('./wkt');

var projStr = require('./projString');

function testObj(code){

  return typeof code === 'string';

}

function testDef(code){

  return code in defs;

}

function testWKT(code){

  var codeWords = ['GEOGCS','GEOCCS','PROJCS','LOCAL_CS'];

  return codeWords.reduce(function(a,b){

    return a+1+code.indexOf(b);

  },0);

}

function testProj(code){

  return code[0] === '+';

}

function parse(code){

  if (testObj(code)) {

    //check to see if this is a WKT string

    if (testDef(code)) {

      return defs[code];

    }

    else if (testWKT(code)) {

      return wkt(code);

    }

    else if (testProj(code)) {

      return projStr(code);

    }

  }else{

    return code;

  }

}



module.exports = parse;
 
 No newline at end of file

lib/projections/merc.js

+6 −0
Original line number Diff line number Diff line
@@ -9,6 +9,12 @@ var phi2z = require('../common/phi2z'); 
exports.init = function() {

  var con = this.b / this.a;

  this.es = 1 - con * con;

  if(!('x0' in this)){

    this.x0 = 0;

  }

  if(!('y0' in this)){

    this.y0 = 0;

  }

  this.e = Math.sqrt(this.es);

  if (this.lat_ts) {

    if (this.sphere) {

test/test.js

+1 −1
Original line number Diff line number Diff line
@@ -163,7 +163,7 @@ function startTests(chai, proj4, testPoints) { 
      it('should throw an error for an unknown ref', function() {

        assert.throws(function() {

          new proj4.Proj('fake one');

        }, 'unknown projection', 'should work');

        }, 'fake one', 'should work');

      });

    })

    describe('utility', function() {