ucar.unidata.geoloc.projection

Class Mercator

java.lang.Object

ucar.unidata.geoloc.projection.AbstractProjection

ucar.unidata.geoloc.projection.Mercator

All Implemented Interfaces:

Projection

@Immutable
public class Mercator
extends AbstractProjection

Mercator projection, spherical earth. Projection plane is a cylinder tangent to the earth at tangentLon. See John Snyder, Map Projections used by the USGS, Bulletin 1532, 2nd edition (1983), p 43-47

Field Summary

Fields inherited from class ucar.unidata.geoloc.projection.AbstractProjection

atts, EARTH_RADIUS, INDEX_LAT, INDEX_LON, INDEX_X, INDEX_Y, isLatLon, name, PI, PI_OVER_2, PI_OVER_4, TOLERANCE

Constructor Summary

Constructors

Constructor and Description
Mercator() Constructor with default parameters
Mercator(double lon0, double par) Construct a Mercator Projection.
Mercator(double lon0, double par, double false_easting, double false_northing)
Mercator(double lon0, double par, double false_easting, double false_northing, double radius) Construct a Mercator Projection.

Method Summary

Modifier and Type	Method and Description
Projection	constructCopy() copy constructor - avoid clone !!
static double	convertScaleToStandardParallel(double scale) Convert "scale at standard parellel" to "standard parellel"
boolean	crossSeam(ProjectionPoint pt1, ProjectionPoint pt2) Does the line between these two points cross the projection "seam".
boolean	equals(Object o)
double	getEarthRadius()
double	getFalseEasting() Get the false easting, in km.
double	getFalseNorthing() Get the false northing, in km.
double	getOriginLon() Get the origin longitude.
double	getParallel() Get the first standard parallel
int	hashCode()
ProjectionPoint	latLonToProj(LatLonPoint latLon) Convert a LatLonPoint to projection coordinates.
String	paramsToString() Get the parameters as a String
LatLonPoint	projToLatLon(ProjectionPoint world) Convert projection coordinates to a LatLonPoint.
String	toString() Get a String representation of this projection.

Methods inherited from class ucar.unidata.geoloc.projection.AbstractProjection

addParameter, addParameter, addParameter, addParameter, findProjectionParameter, getClassName, getHeader, getMinOrMaxLon, getName, getProjectionAttributes, getProjectionParameters, getProjectionTypeLabel, isLatLon, latLonToProjBB, projToLatLonBB

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface ucar.unidata.geoloc.Projection

latLonToProj, projToLatLon

Constructor Detail

Mercator

public Mercator()

Constructor with default parameters

Mercator

public Mercator(double lon0,
                double par)

Construct a Mercator Projection.

Parameters:

lon0 - longitude of origin (degrees)

par - standard parallel (degrees). cylinder cuts earth at this latitude.

Mercator

public Mercator(double lon0,
                double par,
                double false_easting,
                double false_northing)

Mercator

public Mercator(double lon0,
                double par,
                double false_easting,
                double false_northing,
                double radius)

Construct a Mercator Projection.

Parameters:

lon0 - longitude of origin (degrees)

par - standard parallel (degrees). cylinder cuts earth at this latitude.

false_easting - false_easting in km

false_northing - false_northing in km

radius - earth radius in km

Method Detail

convertScaleToStandardParallel

public static double convertScaleToStandardParallel(double scale)

Convert "scale at standard parellel" to "standard parellel"

Parameters:

scale - scale at standard parallel

Returns:

standard parallel in degrees

constructCopy

public Projection constructCopy()

Description copied from class: AbstractProjection

copy constructor - avoid clone !!

Specified by:

constructCopy in class AbstractProjection

Returns:

a copy of this Projection.

getParallel

public double getParallel()

Get the first standard parallel

Returns:

the first standard parallel

getOriginLon

public double getOriginLon()

Get the origin longitude.

Returns:

the origin longitude.

getFalseEasting

public double getFalseEasting()

Get the false easting, in km.

Returns:

the false easting.

getFalseNorthing

public double getFalseNorthing()

Get the false northing, in km.

Returns:

the false northing.

getEarthRadius

public double getEarthRadius()

paramsToString

public String paramsToString()

Get the parameters as a String

Specified by:

paramsToString in interface Projection

Specified by:

paramsToString in class AbstractProjection

Returns:

the parameters as a String

toString

public String toString()

Description copied from class: AbstractProjection

Get a String representation of this projection.

Overrides:

toString in class AbstractProjection

Returns:

the name of the projection. This is what gets displayed when you add the projection object to a UI widget (e.g. label, combobox)

crossSeam

public boolean crossSeam(ProjectionPoint pt1,
                         ProjectionPoint pt2)

Does the line between these two points cross the projection "seam".

Parameters:

pt1 - the line goes between these two points

pt2 - the line goes between these two points

Returns:

false if there is no seam

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

latLonToProj

public ProjectionPoint latLonToProj(LatLonPoint latLon)

Description copied from interface: Projection

Convert a LatLonPoint to projection coordinates.

projToLatLon

public LatLonPoint projToLatLon(ProjectionPoint world)

Description copied from interface: Projection

Convert projection coordinates to a LatLonPoint.