org.n52.io.crs

Class WGS84Util

java.lang.Object

org.n52.io.crs.WGS84Util

public class WGS84Util
extends Object

Some utility methods for WGS84 points. Note that all calculations are being made by assuming a spherical shape of the earth (not elliptic). The EARTH_MEAN_RADIUS is used as radius.

Field Summary

Fields

Modifier and Type	Field and Description
protected static double	EARTH_MEAN_RADIUS The mean radius of WGS84 ellipse.
static String	EPSG_4326

Constructor Summary

Constructors

Constructor and Description
WGS84Util()

Method Summary

Modifier and Type	Method and Description
static double	getLatitudeDelta(double distance) Calculates the latitude delta from a point from a given distance.
(package private) static double	getLatitutesCircleRadius(double latitude)
static double	getLongitudeDelta(double latitude, double distance) Calculates the longitude delta for a given distance.
static double	normalizeLatitude(double latitude) Normalizes given latitude to bounds [-90.0,90.0].
static double	normalizeLongitude(double longitude) Normalizes given longitude to bounds [-180.0,180.0].
static double	shortestDistanceBetween(com.vividsolutions.jts.geom.Point a, com.vividsolutions.jts.geom.Point b) Calculates the shortest distance between two points on a great circle.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

EPSG_4326

public static final String EPSG_4326

See Also:

Constant Field Values

EARTH_MEAN_RADIUS

protected static final double EARTH_MEAN_RADIUS

The mean radius of WGS84 ellipse.

See Also:

Constant Field Values

Constructor Detail

WGS84Util

public WGS84Util()

Method Detail

shortestDistanceBetween

public static double shortestDistanceBetween(com.vividsolutions.jts.geom.Point a,
                                             com.vividsolutions.jts.geom.Point b)

Calculates the shortest distance between two points on a great circle.

Parameters:

a - a point.

b - another point.

Returns:

the shortest distance between point A and point B.

getLongitudeDelta

public static double getLongitudeDelta(double latitude,
                                       double distance)

Calculates the longitude delta for a given distance.

Parameters:

latitude - the latitude in radians to calculate the distance delta from.

distance - the distance in kilometer.

Returns:

the longitude delta in degrees.

getLatitudeDelta

public static double getLatitudeDelta(double distance)

Calculates the latitude delta from a point from a given distance.

Parameters:

distance - the distance in kilometer.

Returns:

the latitude delta in degrees.

getLatitutesCircleRadius

static double getLatitutesCircleRadius(double latitude)

Parameters:

latitude - in degrees in radians.

Returns:

the length of the latitude radius.

normalizeLongitude

public static double normalizeLongitude(double longitude)

Normalizes given longitude to bounds [-180.0,180.0].

Parameters:

longitude - in degrees.

Returns:

the normalized longitude.

normalizeLatitude

public static double normalizeLatitude(double latitude)

Normalizes given latitude to bounds [-90.0,90.0].

Parameters:

latitude - in degrees.

Returns:

the normalized latitude.