GeoPoint.java

// Created by plusminus on 21:28:12 - 25.09.2008
package org.osmdroid.util;

import java.io.Serializable;

import org.osmdroid.api.IGeoPoint;
import org.osmdroid.util.constants.GeoConstants;
import org.osmdroid.views.util.constants.MathConstants;

import android.location.Location;
import android.os.Parcel;
import android.os.Parcelable;

/**
 *
 * @author Nicolas Gramlich
 * @author Theodore Hong
 *
 */
public class GeoPoint implements IGeoPoint, MathConstants, GeoConstants, Parcelable, Serializable, Cloneable {

	// ===========================================================
	// Constants
	// ===========================================================

	static final long serialVersionUID = 1L;

	// ===========================================================
	// Fields
	// ===========================================================

	private double mLongitude;
	private double mLatitude;
	private double mAltitude;

	// ===========================================================
	// Constructors
	// ===========================================================

     @Deprecated
	public GeoPoint(final int aLatitudeE6, final int aLongitudeE6) {
		this.mLatitude = aLatitudeE6 / 1E6;
		this.mLongitude = aLongitudeE6 / 1E6;
	}

     @Deprecated
	public GeoPoint(final int aLatitudeE6, final int aLongitudeE6, final int aAltitude) {
		this.mLatitude = aLatitudeE6 / 1E6;
		this.mLongitude = aLongitudeE6 / 1E6;
		this.mAltitude = aAltitude;
	}

	public GeoPoint(final double aLatitude, final double aLongitude) {
		this.mLatitude = aLatitude;
		this.mLongitude = aLongitude;
	}

	public GeoPoint(final double aLatitude, final double aLongitude, final double aAltitude) {
		this.mLatitude = aLatitude;
		this.mLongitude = aLongitude;
		this.mAltitude = aAltitude;
	}

	public GeoPoint(final Location aLocation) {
		this(aLocation.getLatitude(), aLocation.getLongitude(), aLocation.getAltitude());
	}

	public GeoPoint(final GeoPoint aGeopoint) {
		this.mLatitude = aGeopoint.mLatitude;
		this.mLongitude = aGeopoint.mLongitude;
		this.mAltitude = aGeopoint.mAltitude;
	}

	public static GeoPoint fromDoubleString(final String s, final char spacer) {
		final int spacerPos1 = s.indexOf(spacer);
		final int spacerPos2 = s.indexOf(spacer, spacerPos1 + 1);

		if (spacerPos2 == -1) {
			return new GeoPoint(
					 (Double.parseDouble(s.substring(0, spacerPos1))),
					 (Double.parseDouble(s.substring(spacerPos1 + 1, s.length()))));
		} else {
			return new GeoPoint(
					 (Double.parseDouble(s.substring(0, spacerPos1))),
					 (Double.parseDouble(s.substring(spacerPos1 + 1, spacerPos2))),
					 Double.parseDouble(s.substring(spacerPos2 + 1, s.length())));
		}
	}

	public static GeoPoint fromInvertedDoubleString(final String s, final char spacer) {
		final int spacerPos1 = s.indexOf(spacer);
		final int spacerPos2 = s.indexOf(spacer, spacerPos1 + 1);

		if (spacerPos2 == -1) {
			return new GeoPoint(
					Double.parseDouble(s.substring(spacerPos1 + 1, s.length())),
					Double.parseDouble(s.substring(0, spacerPos1)));
		} else {
			return new GeoPoint(
					Double.parseDouble(s.substring(spacerPos1 + 1, spacerPos2)),
					Double.parseDouble(s.substring(0, spacerPos1)),
					Double.parseDouble(s.substring(spacerPos2 + 1, s.length())));

		}
	}

	public static GeoPoint fromIntString(final String s) {
		final int commaPos1 = s.indexOf(',');
		final int commaPos2 = s.indexOf(',', commaPos1 + 1);

		if (commaPos2 == -1) {
			return new GeoPoint(
					Integer.parseInt(s.substring(0, commaPos1)),
					Integer.parseInt(s.substring(commaPos1 + 1, s.length())));
		} else {
			return new GeoPoint(
					Integer.parseInt(s.substring(0, commaPos1)),
					Integer.parseInt(s.substring(commaPos1 + 1, commaPos2)),
					Integer.parseInt(s.substring(commaPos2 + 1, s.length()))
			);
		}
	}

	// ===========================================================
	// Getter & Setter
	// ===========================================================

	@Override
	public double getLongitude() {
		return this.mLongitude;
	}

	@Override
	public double getLatitude() {
		return this.mLatitude;
	}

	public double getAltitude() {
		return this.mAltitude;
	}

    public void setLatitude(final double aLatitude) { this.mLatitude = aLatitude; }

    public void setLongitude(final double aLongitude) { this.mLongitude = aLongitude; }

	public void setAltitude(final double aAltitude) {
		this.mAltitude = aAltitude;
	}

	public void setCoords(final double aLatitude, final double aLongitude) {
		this.mLatitude = aLatitude;
		this.mLongitude = aLongitude;
	}

	// ===========================================================
	// Methods from SuperClass/Interfaces
	// ===========================================================

	@Override
	public GeoPoint clone() {
		return new GeoPoint(this.mLatitude, this.mLongitude, this.mAltitude);
	}
     
	public String toIntString() {
		return new StringBuilder().
               append(((int)(this.mLatitude*1E6))).
               append(",").
               append(((int)(this.mLongitude*1E6))).
               append(",").
               append((int)(this.mAltitude))
		.toString();
	}

	@Override
	public String toString() {
		return new StringBuilder().append(this.mLatitude).append(",").append(this.mLongitude).append(",").append(this.mAltitude)
		.toString();
	}

	@Override
	public boolean equals(final Object obj) {
		if (obj == null) {
			return false;
		}
		if (obj == this) {
			return true;
		}
		if (obj.getClass() != getClass()) {
			return false;
		}
		final GeoPoint rhs = (GeoPoint) obj;
		return rhs.mLatitude == this.mLatitude && rhs.mLongitude == this.mLongitude && rhs.mAltitude == this.mAltitude;
	}

	@Override
	public int hashCode() {
		return 37 * (17 * (int)(mLatitude*1E-6) + (int)(mLongitude*1E-6)) + (int)mAltitude;
	}

	// ===========================================================
	// Parcelable
	// ===========================================================
	private GeoPoint(final Parcel in) {
		this.mLatitude = in.readDouble();
		this.mLongitude = in.readDouble();
		this.mAltitude = in.readDouble();
	}

	@Override
	public int describeContents() {
		return 0;
	}

	@Override
	public void writeToParcel(final Parcel out, final int flags) {
		out.writeDouble(mLatitude);
		out.writeDouble(mLongitude);
		out.writeDouble(mAltitude);
	}

	public static final Parcelable.Creator<GeoPoint> CREATOR = new Parcelable.Creator<GeoPoint>() {
		@Override
		public GeoPoint createFromParcel(final Parcel in) {
			return new GeoPoint(in);
		}

		@Override
		public GeoPoint[] newArray(final int size) {
			return new GeoPoint[size];
		}
	};

	// ===========================================================
	// Methods
	// ===========================================================

	/**
	 * @see <a href="http://www.geocities.com/DrChengalva/GPSDistance.html">GPSDistance.html</a>
	 * @return distance in meters
	 */
	public int distanceTo(final IGeoPoint other) {

		final double a1 = DEG2RAD * this.mLatitude;
		final double a2 = DEG2RAD * this.mLongitude;
		final double b1 = DEG2RAD * other.getLatitude();
		final double b2 = DEG2RAD * other.getLongitude();

		final double cosa1 = Math.cos(a1);
		final double cosb1 = Math.cos(b1);

		final double t1 = cosa1 * Math.cos(a2) * cosb1 * Math.cos(b2);

		final double t2 = cosa1 * Math.sin(a2) * cosb1 * Math.sin(b2);

		final double t3 = Math.sin(a1) * Math.sin(b1);

		final double tt = Math.acos(t1 + t2 + t3);

		return (int) (RADIUS_EARTH_METERS * tt);
	}

	/**
	 * @see <a href="http://groups.google.com/group/osmdroid/browse_thread/thread/d22c4efeb9188fe9/bc7f9b3111158dd">discussion</a>
	 * @return bearing in degrees
	 */
	public double bearingTo(final IGeoPoint other) {
		final double lat1 = Math.toRadians(this.mLatitude);
		final double long1 = Math.toRadians(this.mLongitude);
		final double lat2 = Math.toRadians(other.getLatitude());
		final double long2 = Math.toRadians(other.getLongitude());
		final double delta_long = long2 - long1;
		final double a = Math.sin(delta_long) * Math.cos(lat2);
		final double b = Math.cos(lat1) * Math.sin(lat2) -
						 Math.sin(lat1) * Math.cos(lat2) * Math.cos(delta_long);
		final double bearing = Math.toDegrees(Math.atan2(a, b));
		final double bearing_normalized = (bearing + 360) % 360;
		return bearing_normalized;
	}

	/**
	 * Calculate a point that is the specified distance and bearing away from this point.
	 *
	 * @see <a href="http://www.movable-type.co.uk/scripts/latlong.html">latlong.html</a>
	 * @see <a href="http://www.movable-type.co.uk/scripts/latlon.js">latlon.js</a>
	 */
	public GeoPoint destinationPoint(final double aDistanceInMeters, final float aBearingInDegrees) {

		// convert distance to angular distance
		final double dist = aDistanceInMeters / RADIUS_EARTH_METERS;

		// convert bearing to radians
		final float brng = DEG2RAD * aBearingInDegrees;

		// get current location in radians
		final double lat1 = DEG2RAD * getLatitude();
		final double lon1 = DEG2RAD * getLongitude();

		final double lat2 = Math.asin(Math.sin(lat1) * Math.cos(dist) + Math.cos(lat1)
				* Math.sin(dist) * Math.cos(brng));
		final double lon2 = lon1
		+ Math.atan2(Math.sin(brng) * Math.sin(dist) * Math.cos(lat1), Math.cos(dist)
				- Math.sin(lat1) * Math.sin(lat2));

		final double lat2deg = lat2 / DEG2RAD;
		final double lon2deg = lon2 / DEG2RAD;

		return new GeoPoint(lat2deg, lon2deg);
	}

	public static GeoPoint fromCenterBetween(final GeoPoint geoPointA, final GeoPoint geoPointB) {
		return new GeoPoint((geoPointA.getLatitude() + geoPointB.getLatitude()) / 2,
				(geoPointA.getLongitude() + geoPointB.getLongitude()) / 2);
	}

	public String toDoubleString() {
		return new StringBuilder().append(this.mLatitude).append(",")
		.append(this.mLongitude).append(",").append(this.mAltitude).toString();
	}

	public String toInvertedDoubleString() {
		return new StringBuilder().append(this.mLongitude).append(",")
		.append(this.mLatitude).append(",").append(this.mAltitude).toString();
	}

	// ===========================================================
	// Inner and Anonymous Classes
	// ===========================================================

     @Deprecated 
     @Override
     public int getLatitudeE6() {
          return (int) (this.getLatitude() * 1E6);
     }

     @Deprecated
     @Override
     public int getLongitudeE6() {
          return (int) (this.getLongitude()* 1E6);
     }
}