ucar.unidata.geoloc.projection.proj4
Class AlbersEqualAreaEllipse

java.lang.Object
  ucar.unidata.geoloc.ProjectionImpl
      ucar.unidata.geoloc.projection.proj4.AlbersEqualAreaEllipse

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, Projection

public class AlbersEqualAreaEllipse
extends ProjectionImpl

Adapted from com.jhlabs.map.proj.AlbersProjection

Since:

Oct 8, 2009

Author:

caron

See Also:

"http://www.jhlabs.com/java/maps/proj/index.html", "http://trac.osgeo.org/proj/", Serialized Form

Field Summary

Fields inherited from class ucar.unidata.geoloc.ProjectionImpl

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

Constructor Summary

AlbersEqualAreaEllipse()
Constructor with default parameters

AlbersEqualAreaEllipse(double lat0, double lon0, double par1, double par2, double falseEasting, double falseNorthing, Earth earth)
Construct a AlbersEqualAreaEllipse Projection, two standard parellels.

Method Summary

java.lang.Object	clone() Clone this projection.
ProjectionImpl	constructCopy() copy constructor - avoid clone !!
boolean	crossSeam(ProjectionPoint pt1, ProjectionPoint pt2) This returns true when the line between pt1 and pt2 crosses the seam.
boolean	equals(java.lang.Object proj) Check for equality with the Object in question
Earth	getEarth()
double	getFalseEasting() Get the false easting, in km.
double	getFalseNorthing() Get the false northing, in km.
double	getOriginLat() Get the origin latitude.
double	getOriginLon() Get the origin longitude.
double	getParallelOne() Get the first standard parallel
double	getParallelTwo() Get the second standard parallel
java.lang.String	getProjectionTypeLabel() Get the label to be used in the gui for this type of projection
ProjectionPoint	latLonToProj(LatLonPoint latLon, ProjectionPointImpl result) Convert a LatLonPoint to projection coordinates
static void	main(java.lang.String[] args)
java.lang.String	paramsToString() Create a String of the parameters.
LatLonPoint	projToLatLon(ProjectionPoint world, LatLonPointImpl result) Convert projection coordinates to a LatLonPoint Note: a new object is not created on each call for the return value.

Methods inherited from class ucar.unidata.geoloc.ProjectionImpl

addParameter, addParameter, addParameter, getClassName, getDefaultMapArea, getDefaultMapAreaLL, getHeader, getLatLonBoundingBox, getName, getProjectionParameters, isLatLon, latLonToProj, latLonToProj, latLonToProj, latLonToProj, latLonToProj, latLonToProj, latLonToProj, latLonToProj, latLonToProj, latLonToProj, latLonToProjBB, projToLatLon, projToLatLon, projToLatLon, projToLatLon, projToLatLon, projToLatLon, projToLatLonBB, setDefaultMapArea, setName, toString

Methods inherited from class java.lang.Object

finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

AlbersEqualAreaEllipse

public AlbersEqualAreaEllipse()

Constructor with default parameters

AlbersEqualAreaEllipse

public AlbersEqualAreaEllipse(double lat0,
                              double lon0,
                              double par1,
                              double par2,
                              double falseEasting,
                              double falseNorthing,
                              Earth earth)

Construct a AlbersEqualAreaEllipse Projection, two standard parellels. For the one standard parellel case, set them both to the same value.

Parameters:

lat0 - lat origin of the coord. system on the projection plane

lon0 - lon origin of the coord. system on the projection plane

par1 - standard parallel 1

par2 - standard parallel 2

falseEasting - false easting in km

falseNorthing - false easting in km

earth - shape of the earth

Throws:

java.lang.IllegalArgumentException - if Math.abs(par1 + par2) < 1.e-10

Method Detail

constructCopy

public ProjectionImpl constructCopy()

copy constructor - avoid clone !!

Specified by:

constructCopy in class ProjectionImpl

Returns:

a copy of this Projection

clone

public java.lang.Object clone()

Clone this projection.

Overrides:

clone in class ProjectionImpl

Returns:

Clone of this

equals

public boolean equals(java.lang.Object proj)

Check for equality with the Object in question

Specified by:

equals in interface Projection

Specified by:

equals in class ProjectionImpl

Parameters:

proj - object to check

Returns:

true if they are equal

getEarth

public Earth getEarth()

getParallelTwo

public double getParallelTwo()

Get the second standard parallel

Returns:

the second standard parallel in degrees

getParallelOne

public double getParallelOne()

Get the first standard parallel

Returns:

the first standard parallel in degrees

getOriginLon

public double getOriginLon()

Get the origin longitude.

Returns:

the origin longitude in degrees

getOriginLat

public double getOriginLat()

Get the origin latitude.

Returns:

the origin latitude in degrees

getFalseEasting

public double getFalseEasting()

Get the false easting, in km.

Returns:

the false easting in km

getFalseNorthing

public double getFalseNorthing()

Get the false northing, in km.

Returns:

the false northing in km

getProjectionTypeLabel

public java.lang.String getProjectionTypeLabel()

Get the label to be used in the gui for this type of projection

Overrides:

getProjectionTypeLabel in class ProjectionImpl

Returns:

Type label

paramsToString

public java.lang.String paramsToString()

Create a String of the parameters.

Specified by:

paramsToString in interface Projection

Specified by:

paramsToString in class ProjectionImpl

Returns:

a String of the parameters

crossSeam

public boolean crossSeam(ProjectionPoint pt1,
                         ProjectionPoint pt2)

This returns true when the line between pt1 and pt2 crosses the seam. When the cone is flattened, the "seam" is lon0 +- 180.

Specified by:

crossSeam in interface Projection

Specified by:

crossSeam in class ProjectionImpl

Parameters:

pt1 - point 1

pt2 - point 2

Returns:

true when the line between pt1 and pt2 crosses the seam.

latLonToProj

public ProjectionPoint latLonToProj(LatLonPoint latLon,
                                    ProjectionPointImpl result)

Description copied from class: ProjectionImpl

Convert a LatLonPoint to projection coordinates

Specified by:

latLonToProj in interface Projection

Specified by:

latLonToProj in class ProjectionImpl

Parameters:

latLon - convert from these lat, lon coordinates

result - the object to write to

Returns:

the given destPoint

projToLatLon

public LatLonPoint projToLatLon(ProjectionPoint world,
                                LatLonPointImpl result)

Convert projection coordinates to a LatLonPoint Note: a new object is not created on each call for the return value.

Specified by:

projToLatLon in interface Projection

Specified by:

projToLatLon in class ProjectionImpl

Parameters:

world - convert from these projection coordinates

result - the object to write to

Returns:

LatLonPoint convert to these lat/lon coordinates public LatLonPoint projToLatLon(ProjectionPoint world, LatLonPointImpl result) { double toLat, toLon; double fromX = world.getX() - falseEasting; double fromY = world.getY() - falseNorthing; double rrho0 = rho0; if (n < 0) { rrho0 *= -1.0; fromX *= -1.0; fromY *= -1.0; } double yd = rrho0 - fromY; double rho = Math.sqrt(fromX * fromX + yd * yd); double theta = Math.atan2(fromX, yd); if (n < 0) { rho *= -1.0; } toLat = Math.toDegrees(Math.asin((C - Math.pow((rho * n / EARTH_RADIUS), 2)) / (2 * n))); toLon = Math.toDegrees(theta / n + lon0); result.setLatitude(toLat); result.setLongitude(toLon); return result; } public Point2D.Double projectInverse(double xyx, double xyy, Point2D.Double out) { double rho; if ((rho = MapMath.distance(xyx, xyy = rho0 - xyy)) != 0) { double lpphi, lplam; if (n < 0.) { rho = -rho; xyx = -xyx; xyy = -xyy; } lpphi = rho / dd; if (!spherical) { lpphi = (c - lpphi * lpphi) / n; if (Math.abs(ec - Math.abs(lpphi)) > TOL7) { if ((lpphi = phi1_(lpphi, e, one_es)) == Double.MAX_VALUE) throw new ProjectionException("I"); } else lpphi = lpphi < 0. ? -MapMath.HALFPI : MapMath.HALFPI; } else if (Math.abs(out.y = (c - lpphi * lpphi) / n2) <= 1.) lpphi = Math.asin(lpphi); else lpphi = lpphi < 0. ? -MapMath.HALFPI : MapMath.HALFPI; lplam = Math.atan2(xyx, xyy) / n; out.x = lplam; out.y = lpphi; } else { out.x = 0.; out.y = n > 0. ? MapMath.HALFPI : - MapMath.HALFPI; } return out; }

main

public static void main(java.lang.String[] args)