Package noaa.coastwatch.util.trans

Class GeographicProjection

java.lang.Object

noaa.coastwatch.util.MetadataContainer

noaa.coastwatch.util.trans.EarthTransform

noaa.coastwatch.util.trans.EarthTransform2D

noaa.coastwatch.util.trans.MapProjection

noaa.coastwatch.util.trans.GCTPStyleProjection

noaa.coastwatch.util.trans.GCTPCStyleProjection

noaa.coastwatch.util.trans.GeographicProjection

All Implemented Interfaces:

Cloneable, ProjectionConstants

public class GeographicProjection
extends GCTPCStyleProjection

The GeographicProjection class performs geographic map projection calculations.

Since:

3.3.0

Author:

Peter Hollemans

Field Summary

Fields inherited from class noaa.coastwatch.util.trans.GCTPCStyleProjection

ERROR, IN_BREAK, LAT, LON, OK, params, X, Y

Fields inherited from class noaa.coastwatch.util.trans.GCTPStyleProjection

C3P, D2R, ec, ec2, EPSLN, falseEast, falseNorth, HALF_PI, PI, R2D, rMajor, TWO_PI

Fields inherited from class noaa.coastwatch.util.trans.MapProjection

datum, DESCRIPTION, forwardAffine, inverseAffine, spheroid, system, zone

Fields inherited from class noaa.coastwatch.util.trans.EarthTransform

boundaryHandler, dims

Fields inherited from interface noaa.coastwatch.util.trans.ProjectionConstants

ALASKA, ALBERS, AZMEQD, EQRECT, EQUIDC, GEO, GNOMON, GOOD, GVNSP, HAMMER, HOM, IMOLL, LAMAZ, LAMCC, MAX_PROJECTIONS, MERCAT, MILLER, MOLL, OBEQA, ORTHO, POLYC, PROJECTION_NAMES, PS, ROBIN, SNSOID, SOM, SPCS, STEREO, TM, USDEF, UTM, VGRINT, WAGIV, WAGVII

Constructor Summary

Constructors

Constructor	Description
GeographicProjection(double rMajor, double rMinor, int[] dimensions, AffineTransform affine)	Constructs a map projection from the specified projection and affine transform.

Method Summary

Modifier and Type	Method	Description
MapProjection	getSubset(int[] start, int[] stride, int[] length)	Creates a subset version of this map projection.
EarthTransform	getSubset(DataLocation newOrigin, int[] newDims)	Creates and returns a new subset transform.
boolean	isBoundaryCut(EarthLocation a, EarthLocation b)	The geographic implementation of the boundary cut test.
protected long	projfor(double lat, double lon, double[] x, double[] y)	Performs the actual forward calculation as specified in the GCTP C code.
protected long	projinv(double x, double y, double[] lon, double[] lat)	Performs the actual inverse calculation as specified in the GCTP C code.
protected void	setAffine(EarthLocation centerLoc, double[] pixelDims)	Sets the affines for this projection based on center and pixel dimensions.
protected void	transformImpl(DataLocation dataLoc, EarthLocation earthLoc)	Implements the data to geographic transform.
protected void	transformImpl(EarthLocation earthLoc, DataLocation dataLoc)	Implements the geographic to data transform.

Methods inherited from class noaa.coastwatch.util.trans.GCTPCStyleProjection

cenlat, cenlon, cenlonmer, genrpt, genrpt_long, getParameters, mapTransformFor, mapTransformInv, offsetp, origin, p_error, p_error, p_error, paksz, phi1z, phi2z, phi3z, phi4z, ptitle, radius, radius2, setParameters, sprintf, stanparl, stparl1

Methods inherited from class noaa.coastwatch.util.trans.GCTPStyleProjection

adjust_lon, asinz, calc_utm_zone, e0fn, e1fn, e2fn, e3fn, e4fn, mlfn, msfnz, pack_angle, pakcz, pakr2dm, phi1z, phi2z, phi3z, phi4z, qsfnz, setDatum, setFalse, sign, sphdz, tsfnz, unpack_angle

Methods inherited from class noaa.coastwatch.util.trans.MapProjection

clone, describe, equals, getAffine, getDatum, getModified, getPixelDimensions, getPixelSize, getProjection, getSpheroid, getSpheroidName, getSystem, getSystemName, getZone, isOrientable, setPositiveLon

Methods inherited from class noaa.coastwatch.util.trans.EarthTransform2D

get2DVersion, getBoundingBox, getWorldAxes, main, setPointTransform, transformToPoint

Methods inherited from class noaa.coastwatch.util.trans.EarthTransform

distance, getBoundaryHandler, getDimensions, getResolution, getSpheroid, getSpheroid, isInvertible, transform, transform, transform, transform

Methods inherited from class noaa.coastwatch.util.MetadataContainer

getMetadataMap

Methods inherited from class java.lang.Object

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

Constructor Details

GeographicProjection

public GeographicProjection(double rMajor,
 double rMinor,
 int[] dimensions,
 AffineTransform affine)
                     throws NoninvertibleTransformException

Constructs a map projection from the specified projection and affine transform. The SpheroidConstants and ProjectionConstants class should be consulted for valid parameter constants.

Parameters:

rMajor - the semi-major axis in meters.

rMinor - the semi-minor axis in meters.

dimensions - the dimensions of the data grid as [rows, columns].

affine - the affine transform for translating data [row, column] to map [x, y].

Throws:

NoninvertibleTransformException - if the map projection to data coordinate affine transform is not invertible.

Method Details

setAffine

protected void setAffine(EarthLocation centerLoc,
 double[] pixelDims)
                  throws NoninvertibleTransformException

Description copied from class: MapProjection

Sets the affines for this projection based on center and pixel dimensions.

Overrides:

setAffine in class MapProjection

Parameters:

centerLoc - the earth location at the map center.

pixelDims - the pixel dimensions in meters at the projection reference point as [height, width].

Throws:

NoninvertibleTransformException - if the map projection to data coordinate affine transform is not invertible.

getSubset

public EarthTransform getSubset(DataLocation newOrigin,
 int[] newDims)

Description copied from class: EarthTransform

Creates and returns a new subset transform. The new transform is arranged with the specified new origin and dimensions. For example, if the transform maps the data location (100,100) to earth location (40N, 120W), and a translated transform is created with (100,100) as the new origin, then the new transform will map (0,0) to (40N, 120W). Note that not all transforms support subsets.

Overrides:

getSubset in class MapProjection

Parameters:

newOrigin - the new data location origin.

newDims - the new data location dimensions.

getSubset

public MapProjection getSubset(int[] start,
 int[] stride,
 int[] length)

Description copied from class: MapProjection

Creates a subset version of this map projection.

Overrides:

getSubset in class MapProjection

Parameters:

start - the 2D starting data coordinates.

stride - the 2D data stride.

length - the total number of values in each dimension.

Returns:

the subset and/or subsampled transform.

transformImpl

protected void transformImpl(DataLocation dataLoc,
 EarthLocation earthLoc)

Description copied from class: EarthTransform

Implements the data to geographic transform.

Overrides:

transformImpl in class MapProjection

See Also:

• EarthTransform.transform(DataLocation,EarthLocation)

transformImpl

protected void transformImpl(EarthLocation earthLoc,
 DataLocation dataLoc)

Description copied from class: EarthTransform

Implements the geographic to data transform.

Overrides:

transformImpl in class MapProjection

See Also:

• EarthTransform.transform(EarthLocation,DataLocation)

projfor

protected long projfor(double lat,
 double lon,
 double[] x,
 double[] y)

Description copied from class: GCTPCStyleProjection

Performs the actual forward calculation as specified in the GCTP C code. This method is as close as possible to the native C function signature.

Specified by:

projfor in class GCTPCStyleProjection

Parameters:

lat - the latitude to convert.

lon - the longitude to convert.

x - the map coordinate x value (modified).

y - the map coordinate y value (modified).

Returns:

OK on success, or not OK on failure.

projinv

protected long projinv(double x,
 double y,
 double[] lon,
 double[] lat)

Description copied from class: GCTPCStyleProjection

Performs the actual inverse calculation as specified in the GCTP C code. This method is as close as possible to the native C function signature.

Specified by:

projinv in class GCTPCStyleProjection

Parameters:

x - the map coordinate x value (modified).

y - the map coordinate y value (modified).

lon - the longitude to convert.

lat - the latitude to convert.

Returns:

OK on success, or not OK on failure.

isBoundaryCut

public boolean isBoundaryCut(EarthLocation a,
 EarthLocation b)

The geographic implementation of the boundary cut test.