init

2026-10-21 19:32:02 -04:00
commit b74d278c8e
96 changed files with 54476 additions and 0 deletions
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+var SphericalCoord = require('./spherical.js');
+var Ellipsoid = require('../ellipsoid.js');
+
+module.exports = GeodeticCoord;
+
+function GeodeticCoord(options){
+	this.options = options;
+	this.lambda = options.lambda || options.lon; // longitude
+	this.phi = options.phi || options.lat; // geodetic latitude
+	this.height_above_ellipsoid = options.height_above_ellipsoid || 0;
+	this.ellipsoid = options.ellipsoid || new Ellipsoid();
+}
+
+GeodeticCoord.prototype.toSpherical = function() {
+	var ellipsoid = this.ellipsoid;
+	var coslat = Math.cos(this.phi*Math.PI/180);
+	var sinlat = Math.sin(this.phi*Math.PI/180);
+	var rc = ellipsoid.a / Math.sqrt(1 - ellipsoid.epssq * sinlat * sinlat);
+	var xp = (rc + this.height_above_ellipsoid) * coslat;
+	var zp = (rc * (1 - ellipsoid.epssq) + this.height_above_ellipsoid) * sinlat;
+	var r = Math.sqrt(xp*xp + zp*zp);
+	return new SphericalCoord({
+		r: r,
+		phig: 180/Math.PI*Math.asin(zp / r),
+		lambda: this.lambda
+	});
+};
+
+GeodeticCoord.prototype.clone = function(){
+	return new GeodeticCoord(this.options);
+};