//**********************************************************************//// <copyright>////  BBN Technologies//  10 Moulton Street//  Cambridge, MA 02138//  (617) 873-8000////  Copyright (C) BBNT Solutions LLC. All rights reserved.//// </copyright>// **********************************************************************//// $Source: /cvs/distapps/openmap/src/openmap/com/bbn/openmap/proj/coords/UPSPoint.java,v $// $RCSfile: UPSPoint.java,v $// $Revision: 1.5.2.2 $// $Date: 2005/08/11 21:03:11 $// $Author: dietrick $//// **********************************************************************package com.bbn.openmap.proj.coords;import com.bbn.openmap.LatLonPoint;/** * Class UPSPoint. * <p> * This class encapsulates a UPS point. * <p> * UPS is known as (Universal Polar Stereographic). * <p> * UPS is a coordinate system of Earth's polar regions north of * <p> * 84 degrees north, and south of 80 degrees south. * <p> * This class defaults to WGS-1984. * <p> *  * @author Bob Hayes */public class UPSPoint {    /** Easting */    protected double easting;    /** Northing */    protected double northing;    /** Hemisphere */    //protected boolean southernHemisphere;    private double Degree = Math.PI / 180.0;    //WGS-1984: 6378137.0, 298.257223563 0.00669438d    /** Constructor for the UPSPoint object */    public UPSPoint() {        this.easting = 0;        this.northing = 0;        //southernHemisphere = false;    }    /**     * Constructor for the UPSPoint object     *      * @param easting easting     * @param northing northing     */    public UPSPoint(double easting, double northing) {        this.easting = easting;        this.northing = northing;        //southernHemisphere = southern;    }    /**     * Static method to create a UPSPoint object from lat/lon     * coordiantes. Method avoids conflict with (double, double)     * constructor.     *      * @param lat latitude in decimal degrees     * @param lon longitude in decimal degrees     */    public static UPSPoint createUPSPoint(double lat, double lon) {        UPSPoint ups = new UPSPoint();        ups.toUPS(lat, lon);        return ups;    }    /**     * Constructor for the UPSPoint object     *      * @param llpt LatLonPoint     */    public UPSPoint(LatLonPoint llpt) {        double lat = (double) llpt.getLatitude();        double lon = (double) llpt.getLongitude();        this.toUPS(lat, lon);    }    /**     * Converts a lat-lon pair to UPS point     *      * @param lat latitude in decimal degrees     * @param lon longitude in decimal degrees     */    public void toUPS(double lat, double lon) {        double a = 0;        double t = 0;        double e = 0;        double es = 0;        double rho = 0;        double x;        double y;        final double k0 = 0.994;        double lambda = lon * Degree;        double phi = Math.abs(lat * Degree);        //double phi = (lat * Degree);        a = 6378137.0;        es = 0.00669438d;        e = Math.sqrt(es);        t = Math.tan(Math.PI / 4.0 - phi / 2.0)                / Math.pow((1.0 - e * Math.sin(phi))                        / (1.0 + e * Math.sin(phi)), (e / 2.0));        rho = 2.0                * a                * k0                * t                / Math.sqrt(Math.pow(1.0 + e, 1.0 + e)                        * Math.pow(1.0 - e, 1.0 - e));        x = rho * Math.sin(lambda);        y = rho * Math.cos(lambda);        if (lat > 0.0) {            // Northern hemisphere            y = -(y);            //southernHemisphere = false;        }        x += 2.0e6;        // Add in false easting and northing        y += 2.0e6;        easting = x;        northing = y;    }    /*     * ---------------------------------------------------------------------------------     */    /**     * Convert a UPSPoint to a LatLonPoint     *      * @return returns a LatLonPoint     */    public LatLonPoint toLatLonPoint(boolean southernHemisphere) {        LatLonPoint llp = new LatLonPoint();        double lon = 0;        double lat = 0;        double a = 0;        double es = 0;        double e = 0;        double t = 0;        double rho = 0;        double x = easting;        double y = northing;        final double k0 = 0.994;        a = 6378137.0;        es = 0.00669438d;        e = Math.sqrt(es);        x -= 2.0e6;        // Remove false easting and northing        y -= 2.0e6;        rho = Math.sqrt(x * x + y * y);        t = rho                * Math.sqrt(Math.pow(1.0 + e, 1.0 + e)                        * Math.pow(1.0 - e, 1.0 - e)) / (2.0 * a * k0);        lat = calcPhi(e, t);        lat /= Degree;        if (y != 0.0) {            t = Math.atan(Math.abs(x / y));        } else {            t = Math.PI / 2.0;            if (x < 0.0) {                t = -t;            }        }        if (southernHemisphere == false) {            y = -y;        } else {            lat = -lat;        }        if (y < 0.0) {            t = Math.PI - t;        }        if (x < 0.0) {            t = -t;        }        lon = t / Degree;        llp.setLatitude((float) lat);        llp.setLongitude((float) lon);        return llp;    }    /*     * ---------------------------------------------------------------------------------     */    /**     * Sets the northing attribute     *      * @param northing The new northing value     */    public void setNorthing(double northing) {        this.northing = northing;    }    /**     * Sets the easting attribute     *      * @param easting The new easting value     */    public void setEasting(double easting) {        this.easting = easting;    }    /**     * Gets the easting attribute     *      * @return The easting value     */    public double getNorthing() {        return northing;    }    /**     * Gets the easting attribute     *      * @return The easting value     */    public double getEasting() {        return easting;    }    /**     * Description of the Method     *      * @return returns a string representation of the object     */    public String toString() {        return "Easting:" + easting + " Northing:" + northing;    }    /**     * Calculate phi (latitude)     *      * @param e     * @param t     * @return phi     */    static double calcPhi(double e, double t) {        double phi = 0;        double old = Math.PI / 2.0 - 2.0 * Math.atan(t);        short maxIterations = 20;        while ((Math.abs((phi - old) / phi) > 1.0e-8) && (maxIterations != 0)) {            old = phi;            phi = Math.PI                    / 2.0                    - 2.0                    * Math.atan(t                            * Math.pow((1.0 - e * Math.sin(phi))                                    / ((1.0 + e * Math.sin(phi))), (e / 2.0)));            maxIterations--;        }        return phi;    }    /**     * Tested against the NIMA calculator     */    public static void main(String[] args) {        //TEST1 - NORTH & WEST        LatLonPoint llpt1 = new LatLonPoint(87.00, -74.50);        System.out.println(llpt1.toString());        UPSPoint ups = new UPSPoint(llpt1);        System.out.println(ups.toString());        LatLonPoint llpt2 = ups.toLatLonPoint(false);        System.out.println(llpt2.toString());        //TEST2 - SOUTH & EAST        System.out.println("--------------------------------------------");        llpt1 = new LatLonPoint(-89.00, 110.50);        System.out.println(llpt1.toString());        ups = new UPSPoint(llpt1);        System.out.println(ups.toString());        llpt2 = ups.toLatLonPoint(true);        System.out.println(llpt2.toString());    }}