/* * Copyright 2010, 2011, 2012 mapsforge.org * * This program is free software: you can redistribute it and/or modify it under the * terms of the GNU Lesser General Public License as published by the Free Software * Foundation, either version 3 of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, but WITHOUT ANY * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A * PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License along with * this program. If not, see <http://www.gnu.org/licenses/>. */ package org.mapsforge.core.model; import java.io.Serializable; /** * A GeoPoint represents an immutable pair of latitude and longitude coordinates. */ public class GeoPoint implements Comparable<GeoPoint>, Serializable { private static final double EQUATORIAL_RADIUS = 6378137.0; private static final long serialVersionUID = 1L; /** * Creates a new GeoPoint from a comma-separated string of coordinates in the order latitude, longitude. All * coordinate values must be in degrees. * * @param geoPointString * the string that describes the GeoPoint. * @return a new GeoPoint with the given coordinates. * @throws IllegalArgumentException * if the string cannot be parsed or describes an invalid GeoPoint. */ public static GeoPoint fromString(String geoPointString) { double[] coordinates = CoordinatesUtil.parseCoordinateString(geoPointString, 2); return new GeoPoint(coordinates[0], coordinates[1]); } /** * Calculates the amount of degrees of latitude for a given distance in meters. * * @param meters * distance in meters * @return latitude degrees */ public static double latitudeDistance(int meters) { return (meters * 360) / (2 * Math.PI * EQUATORIAL_RADIUS); } /** * Calculates the amount of degrees of longitude for a given distance in meters. * * @param meters * distance in meters * @param latitude * the latitude at which the calculation should be performed * @return longitude degrees */ public static double longitudeDistance(int meters, double latitude) { return (meters * 360) / (2 * Math.PI * EQUATORIAL_RADIUS * Math.cos(Math.toRadians(latitude))); } /** * The latitude coordinate of this GeoPoint in degrees. */ public final double latitude; /** * The longitude coordinate of this GeoPoint in degrees. */ public final double longitude; /** * @param latitude * the latitude coordinate in degrees. * @param longitude * the longitude coordinate in degrees. * @throws IllegalArgumentException * if a coordinate is invalid. */ public GeoPoint(double latitude, double longitude) { CoordinatesUtil.validateLatitude(latitude); CoordinatesUtil.validateLongitude(longitude); this.latitude = latitude; this.longitude = longitude; } @Override public int compareTo(GeoPoint geoPoint) { if (this.longitude > geoPoint.longitude) { return 1; } else if (this.longitude < geoPoint.longitude) { return -1; } else if (this.latitude > geoPoint.latitude) { return 1; } else if (this.latitude < geoPoint.latitude) { return -1; } return 0; } @Override public boolean equals(Object obj) { if (this == obj) { return true; } else if (!(obj instanceof GeoPoint)) { return false; } GeoPoint other = (GeoPoint) obj; if (Double.doubleToLongBits(this.latitude) != Double.doubleToLongBits(other.latitude)) { return false; } else if (Double.doubleToLongBits(this.longitude) != Double.doubleToLongBits(other.longitude)) { return false; } return true; } @Override public int hashCode() { final int prime = 31; int result = 1; long temp; temp = Double.doubleToLongBits(this.latitude); result = prime * result + (int) (temp ^ (temp >>> 32)); temp = Double.doubleToLongBits(this.longitude); result = prime * result + (int) (temp ^ (temp >>> 32)); return result; } @Override public String toString() { StringBuilder stringBuilder = new StringBuilder(); stringBuilder.append("latitude="); stringBuilder.append(this.latitude); stringBuilder.append(", longitude="); stringBuilder.append(this.longitude); return stringBuilder.toString(); } }