ucar.unidata.geoloc.projection
Class Stereographic

java.lang.Object
  extended by ucar.unidata.geoloc.ProjectionImpl
      extended by ucar.unidata.geoloc.projection.Stereographic
All Implemented Interfaces:
java.io.Serializable, java.lang.Cloneable, Projection

public class Stereographic
extends ProjectionImpl

Stereographic projection, spherical earth. Projection plane is a plane tangent to the earth at latt, lont. see John Snyder, Map Projections used by the USGS, Bulletin 1532, 2nd edition (1983), p 153

Version:
$Id: Stereographic.java,v 1.25 2006/11/18 19:03:23 dmurray Exp $
Author:
John Caron
See Also:
Projection, ProjectionImpl, 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, workL, workP
 
Constructor Summary
Stereographic()
          Constructor with default parameters = North Polar
Stereographic(double latt, double lont, double scale)
          Construct a Stereographic Projection.
 
Method Summary
 java.lang.Object clone()
          Clone this projection
 ProjectionImpl constructCopy()
          copy constructor - avoid clone !!
 boolean crossSeam(ProjectionPoint pt1, ProjectionPoint pt2)
          Does the line between these two points cross the projection "seam".
 boolean equals(java.lang.Object proj)
          Returns true if this represents the same Projection as proj.
 double getScale()
          Get the scale
 double getTangentLat()
          Get the tangent latitude
 double getTangentLon()
          Get the tangent longitude
 double[][] latLonToProj(double[][] from, double[][] to, int latIndex, int lonIndex)
          Convert lat/lon coordinates to projection coordinates.
 float[][] latLonToProj(float[][] from, float[][] to, int latIndex, int lonIndex)
          Convert lat/lon coordinates to projection coordinates.
 ProjectionPoint latLonToProj(LatLonPoint latLon, ProjectionPointImpl result)
          Convert a LatLonPoint to projection coordinates
 java.lang.String paramsToString()
          Get the parameters as a String
 double[][] projToLatLon(double[][] from, double[][] to)
          Convert projection coordinates to lat/lon coordinate.
 float[][] projToLatLon(float[][] from, float[][] to)
          Convert projection coordinates to lat/lon coordinate.
 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.
 void setScale(double scale)
          Set the scale
 void setTangentLat(double lat)
          Set the tangent latitude
 void setTangentLon(double lon)
          Set the tangent longitude
 
Methods inherited from class ucar.unidata.geoloc.ProjectionImpl
addParameter, addParameter, addParameter, getClassName, getDefaultMapArea, getDefaultMapAreaLL, getHeader, getName, getProjectionParameters, getProjectionTypeLabel, isLatLon, latLonToProj, latLonToProj, latLonToProj, latLonToProj, latLonToProj, latLonToProj, latLonToProj, latLonToProj, latLonToProjBB, 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

Stereographic

public Stereographic()
Constructor with default parameters = North Polar


Stereographic

public Stereographic(double latt,
                     double lont,
                     double scale)
Construct a Stereographic Projection.

Parameters:
latt - tangent point of projection, also origin of projecion coord system
lont - tangent point of projection, also origin of projecion coord system
scale - scale factor at tangent point, "normally 1.0 but may be reduced"
Method Detail

constructCopy

public ProjectionImpl constructCopy()
copy constructor - avoid clone !!

Specified by:
constructCopy in class ProjectionImpl

getScale

public double getScale()
Get the scale

Returns:
the scale

setScale

public void setScale(double scale)
Set the scale

Parameters:
scale - the scale

getTangentLon

public double getTangentLon()
Get the tangent longitude

Returns:
the tangent longitude

setTangentLon

public void setTangentLon(double lon)
Set the tangent longitude

Parameters:
lon - the tangent longitude

getTangentLat

public double getTangentLat()
Get the tangent latitude

Returns:
the tangent latitude

setTangentLat

public void setTangentLat(double lat)
Set the tangent latitude

Parameters:
lat - the tangent latitude

paramsToString

public java.lang.String paramsToString()
Get the parameters as a String

Specified by:
paramsToString in interface Projection
Specified by:
paramsToString in class ProjectionImpl
Returns:
the parameters as a String

crossSeam

public boolean crossSeam(ProjectionPoint pt1,
                         ProjectionPoint pt2)
Does the line between these two points cross the projection "seam".

Specified by:
crossSeam in interface Projection
Specified by:
crossSeam in class ProjectionImpl
Parameters:
pt1 - the line goes between these two points
pt2 - the line goes between these two points
Returns:
false if there is no seam

clone

public java.lang.Object clone()
Clone this projection

Overrides:
clone in class ProjectionImpl
Returns:
a clone of this.

equals

public boolean equals(java.lang.Object proj)
Returns true if this represents the same Projection as proj.

Specified by:
equals in interface Projection
Specified by:
equals in class ProjectionImpl
Parameters:
proj - projection in question
Returns:
true if this represents the same Projection as proj.

latLonToProj

public ProjectionPoint latLonToProj(LatLonPoint latLon,
                                    ProjectionPointImpl result)
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 result

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

latLonToProj

public float[][] latLonToProj(float[][] from,
                              float[][] to,
                              int latIndex,
                              int lonIndex)
Convert lat/lon coordinates to projection coordinates.

Overrides:
latLonToProj in class ProjectionImpl
Parameters:
from - array of lat/lon coordinates: from[2][n], where (from[latIndex][i], from[lonIndex][i]) is the (lat,lon) coordinate of the ith point
to - resulting array of projection coordinates: to[2][n] where (to[0][i], to[1][i]) is the (x,y) coordinate of the ith point
latIndex - index of lat coordinate; must be 0 or 1
lonIndex - index of lon coordinate; must be 0 or 1
Returns:
the "to" array

projToLatLon

public float[][] projToLatLon(float[][] from,
                              float[][] to)
Convert projection coordinates to lat/lon coordinate.

Overrides:
projToLatLon in class ProjectionImpl
Parameters:
from - array of projection coordinates: from[2][n], where (from[0][i], from[1][i]) is the (x, y) coordinate of the ith point
to - resulting array of lat/lon coordinates: to[2][n] where (to[0][i], to[1][i]) is the (lat, lon) coordinate of the ith point
Returns:
the "to" array

latLonToProj

public double[][] latLonToProj(double[][] from,
                               double[][] to,
                               int latIndex,
                               int lonIndex)
Convert lat/lon coordinates to projection coordinates.

Overrides:
latLonToProj in class ProjectionImpl
Parameters:
from - array of lat/lon coordinates: from[2][n], where (from[latIndex][i], from[lonIndex][i]) is the (lat,lon) coordinate of the ith point
to - resulting array of projection coordinates: to[2][n] where (to[0][i], to[1][i]) is the (x,y) coordinate of the ith point
latIndex - index of lat coordinate; must be 0 or 1
lonIndex - index of lon coordinate; must be 0 or 1
Returns:
the "to" array

projToLatLon

public double[][] projToLatLon(double[][] from,
                               double[][] to)
Convert projection coordinates to lat/lon coordinate.

Overrides:
projToLatLon in class ProjectionImpl
Parameters:
from - array of projection coordinates: from[2][n], where (from[0][i], from[1][i]) is the (x, y) coordinate of the ith point
to - resulting array of lat/lon coordinates: to[2][n] where (to[0][i], to[1][i]) is the (lat, lon) coordinate of the ith point
Returns:
the "to" array