org.opentripplanner.common.geometry

Class SphericalDistanceLibrary

java.lang.Object

org.opentripplanner.common.geometry.SphericalDistanceLibrary

public abstract class SphericalDistanceLibrary
extends Object

Field Summary

Fields

Modifier and Type	Field and Description
static double	MAX_ERR_INV
static double	MAX_LAT_DELTA_DEG
static double	MAX_LON_DELTA_DEG
static double	RADIUS_OF_EARTH_IN_KM
static double	RADIUS_OF_EARTH_IN_M

Constructor Summary

Constructors

Constructor and Description
SphericalDistanceLibrary()

Method Summary

Modifier and Type	Method and Description
static com.vividsolutions.jts.geom.Envelope	bounds(double lat, double lon, double latDistance, double lonDistance)
static double	degreesLatitudeToMeters(double degreesLatitude)
static double	distance(com.vividsolutions.jts.geom.Coordinate from, com.vividsolutions.jts.geom.Coordinate to)
static double	distance(double lat1, double lon1, double lat2, double lon2)
static double	distance(double lat1, double lon1, double lat2, double lon2, double radius)
static double	fastDistance(com.vividsolutions.jts.geom.Coordinate from, com.vividsolutions.jts.geom.Coordinate to)
static double	fastDistance(com.vividsolutions.jts.geom.Coordinate from, com.vividsolutions.jts.geom.Coordinate to, double cosLat)
static double	fastDistance(com.vividsolutions.jts.geom.Coordinate point, com.vividsolutions.jts.geom.LineString lineString) Compute an (approximated) distance between a point and a linestring expressed in standard geographical coordinates (lon, lat in degrees).
static double	fastDistance(double lat1, double lon1, double lat2, double lon2) Compute an (approximated) distance between two points, with a known cos(lat).
static double	fastDistance(double lat1, double lon1, double lat2, double lon2, double radius) Approximated, fast and under-estimated equirectangular distance between two points.
static double	fastLength(com.vividsolutions.jts.geom.LineString lineString) Compute the (approximated) length of a polyline
static double	fastLength(com.vividsolutions.jts.geom.LineString lineString, double cosLat) Compute the (approximated) length of a polyline, with known cos(lat).
static double	metersToDegrees(double distanceMeters)
static double	metersToLonDegrees(double distanceMeters, double latDeg)

Methods inherited from class java.lang.Object

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

Field Detail

RADIUS_OF_EARTH_IN_KM

public static final double RADIUS_OF_EARTH_IN_KM

See Also:

Constant Field Values

RADIUS_OF_EARTH_IN_M

public static final double RADIUS_OF_EARTH_IN_M

See Also:

Constant Field Values

MAX_LAT_DELTA_DEG

public static final double MAX_LAT_DELTA_DEG

See Also:

Constant Field Values

MAX_LON_DELTA_DEG

public static final double MAX_LON_DELTA_DEG

See Also:

Constant Field Values

MAX_ERR_INV

public static final double MAX_ERR_INV

See Also:

Constant Field Values

Constructor Detail

SphericalDistanceLibrary

public SphericalDistanceLibrary()

Method Detail

distance

public static final double distance(com.vividsolutions.jts.geom.Coordinate from,
                                    com.vividsolutions.jts.geom.Coordinate to)

fastDistance

public static final double fastDistance(com.vividsolutions.jts.geom.Coordinate from,
                                        com.vividsolutions.jts.geom.Coordinate to)

fastDistance

public static final double fastDistance(com.vividsolutions.jts.geom.Coordinate from,
                                        com.vividsolutions.jts.geom.Coordinate to,
                                        double cosLat)

fastDistance

public static final double fastDistance(com.vividsolutions.jts.geom.Coordinate point,
                                        com.vividsolutions.jts.geom.LineString lineString)

Compute an (approximated) distance between a point and a linestring expressed in standard geographical coordinates (lon, lat in degrees).

Parameters:

point - The coordinates of the point (longitude, latitude degrees).

lineString - The set of points representing the polyline, in the same coordinate system.

Returns:

The (approximated) distance, in meters, between the point and the linestring.

fastLength

public static final double fastLength(com.vividsolutions.jts.geom.LineString lineString)

Compute the (approximated) length of a polyline

Parameters:

lineString - The polyline in (longitude, latitude degrees).

Returns:

The (approximated) length, in meters, of the linestring.

fastLength

public static final double fastLength(com.vividsolutions.jts.geom.LineString lineString,
                                      double cosLat)

Compute the (approximated) length of a polyline, with known cos(lat).

Parameters:

lineString - The polyline in (longitude, latitude degrees).

Returns:

The (approximated) length, in meters, of the linestring.

distance

public static final double distance(double lat1,
                                    double lon1,
                                    double lat2,
                                    double lon2)

fastDistance

public static final double fastDistance(double lat1,
                                        double lon1,
                                        double lat2,
                                        double lon2)

Compute an (approximated) distance between two points, with a known cos(lat). Be careful, this is approximated and never check for the validity of input cos(lat).

distance

public static final double distance(double lat1,
                                    double lon1,
                                    double lat2,
                                    double lon2,
                                    double radius)

fastDistance

public static final double fastDistance(double lat1,
                                        double lon1,
                                        double lat2,
                                        double lon2,
                                        double radius)

Approximated, fast and under-estimated equirectangular distance between two points. Works only for small delta lat/lon, fall-back on exact distance if not the case. See: http://www.movable-type.co.uk/scripts/latlong.html

metersToDegrees

public static double metersToDegrees(double distanceMeters)

Parameters:

distanceMeters - Distance in meters.

Returns:

The number of degree for the given distance. For degrees latitude, this is nearly correct. For degrees longitude, this is an overestimate because meridians converge toward the poles.

degreesLatitudeToMeters

public static double degreesLatitudeToMeters(double degreesLatitude)

Returns:

the approximate number of meters for the given number of degrees latitude. If degrees longitude are supplied, this is an overestimate anywhere off the equator because meridians converge toward the poles.

metersToLonDegrees

public static double metersToLonDegrees(double distanceMeters,
                                        double latDeg)

Parameters:

distanceMeters - Distance in meters.

latDeg - Latitude of center point, in degree.

Returns:

The number of longitude degree for the given distance. This is a slight overestimate as the number of degree of longitude for a given distance depends on the exact latitude.

bounds

public static final com.vividsolutions.jts.geom.Envelope bounds(double lat,
                                                                double lon,
                                                                double latDistance,
                                                                double lonDistance)