Package org.openstreetmap.josm.data.projection.datum

Class NTV2SubGrid

java.lang.Object

org.openstreetmap.josm.data.projection.datum.NTV2SubGrid

All Implemented Interfaces:

java.io.Serializable

public class NTV2SubGrid
extends java.lang.Object
implements java.io.Serializable

Models the NTv2 Sub Grid within a Grid Shift File.

Since:

2507

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
private java.lang.String	created
private float[]	latAccuracy
private double	latInterval
private int	latRowCount
private float[]	latShift
private float[]	lonAccuracy
private int	lonColumnCount
private double	lonInterval
private float[]	lonShift
private double	maxLat
private double	maxLon
private double	minLat
private double	minLon
private int	nodeCount
private java.lang.String	parentSubGridName
private static long	serialVersionUID
private NTV2SubGrid[]	subGrid
private java.lang.String	subGridName
private java.lang.String	updated

Constructor Summary

Constructors

Constructor	Description
NTV2SubGrid(java.io.InputStream in, boolean bigEndian, boolean loadAccuracy)	Construct a Sub Grid from an InputStream, loading the node data into arrays in this object.

Method Summary

Modifier and Type	Method	Description
java.lang.String	getDetails()	Returns textual details about the sub grid.
double	getMaxLat()	Get maximum latitude value
double	getMaxLon()	Get maximum longitude value
double	getMinLat()	Get minimum latitude value
double	getMinLon()	Get minimum longitude value
int	getNodeCount()	Returns the node count.
java.lang.String	getParentSubGridName()	Returns the parent sub grid name.
int	getSubGridCount()	Returns the sub grid count.
NTV2SubGrid	getSubGridForCoord(double lon, double lat)	Tests if a specified coordinate is within this Sub Grid or one of its Sub Grids.
java.lang.String	getSubGridName()	Returns the sub grid name.
private static double	interpolate(float a, float b, float c, float d, double x, double y)	Bi-Linear interpolation of four nearest node values as described in 'GDAit Software Architecture Manual' produced by the Geomatics Department of the University of Melbourne
void	interpolateGridShift(NTV2GridShift gs)	Interpolate shift and accuracy values for a coordinate in the 'from' datum of the GridShiftFile.
private boolean	isCoordWithin(double lon, double lat)	Tests if a specified coordinate is within this Sub Grid.
private static void	readBytes(java.io.InputStream in, byte[] b)
void	setSubGridArray(NTV2SubGrid... subGrid)	Set an array of Sub Grids of this sub grid
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

serialVersionUID

private static final long serialVersionUID

See Also:

Constant Field Values

subGridName

private final java.lang.String subGridName

parentSubGridName

private final java.lang.String parentSubGridName

created

private final java.lang.String created

updated

private final java.lang.String updated

minLat

private final double minLat

maxLat

private final double maxLat

minLon

private final double minLon

maxLon

private final double maxLon

latInterval

private final double latInterval

lonInterval

private final double lonInterval

nodeCount

private final int nodeCount

lonColumnCount

private final int lonColumnCount

latRowCount

private final int latRowCount

latShift

private final float[] latShift

lonShift

private final float[] lonShift

latAccuracy

private float[] latAccuracy

lonAccuracy

private float[] lonAccuracy

subGrid

private NTV2SubGrid[] subGrid

Constructor Detail

NTV2SubGrid

public NTV2SubGrid(java.io.InputStream in,
                   boolean bigEndian,
                   boolean loadAccuracy)
            throws java.io.IOException

Construct a Sub Grid from an InputStream, loading the node data into arrays in this object.

Parameters:

in - GridShiftFile InputStream

bigEndian - is the file bigEndian?

loadAccuracy - is the node Accuracy data to be loaded?

Throws:

java.io.IOException - if any I/O error occurs

Method Detail

readBytes

private static void readBytes(java.io.InputStream in,
                              byte[] b)
                       throws java.io.IOException

Throws:

java.io.IOException

getSubGridForCoord

public NTV2SubGrid getSubGridForCoord(double lon,
                                      double lat)

Tests if a specified coordinate is within this Sub Grid or one of its Sub Grids. If the coordinate is outside this Sub Grid, null is returned. If the coordinate is within this Sub Grid, but not within any of its Sub Grids, this Sub Grid is returned. If the coordinate is within one of this Sub Grid's Sub Grids, the method is called recursively on the child Sub Grid.

Parameters:

lon - Longitude in Positive West Seconds

lat - Latitude in Seconds

Returns:

the Sub Grid containing the Coordinate or null

isCoordWithin

private boolean isCoordWithin(double lon,
                              double lat)

Tests if a specified coordinate is within this Sub Grid. A coordinate on either outer edge (maximum Latitude or maximum Longitude) is deemed to be outside the grid.

Parameters:

lon - Longitude in Positive West Seconds

lat - Latitude in Seconds

Returns:

true or false

interpolate

private static double interpolate(float a,
                                  float b,
                                  float c,
                                  float d,
                                  double x,
                                  double y)

Bi-Linear interpolation of four nearest node values as described in 'GDAit Software Architecture Manual' produced by the Geomatics Department of the University of Melbourne

Parameters:

a - value at the A node

b - value at the B node

c - value at the C node

d - value at the D node

x - Longitude factor

y - Latitude factor

Returns:

interpolated value

interpolateGridShift

public void interpolateGridShift(NTV2GridShift gs)

Interpolate shift and accuracy values for a coordinate in the 'from' datum of the GridShiftFile. The algorithm is described in 'GDAit Software Architecture Manual' produced by the Geomatics Department of the University of Melbourne

This method is thread safe for both memory based and file based node data.

Parameters:

gs - GridShift object containing the coordinate to shift and the shift values

getParentSubGridName

public java.lang.String getParentSubGridName()

Returns the parent sub grid name.

Returns:

the parent sub grid name

getSubGridName

public java.lang.String getSubGridName()

Returns the sub grid name.

Returns:

the sub grid name

getNodeCount

public int getNodeCount()

Returns the node count.

Returns:

the node count

getSubGridCount

public int getSubGridCount()

Returns the sub grid count.

Returns:

the sub grid count

setSubGridArray

public void setSubGridArray(NTV2SubGrid... subGrid)

Set an array of Sub Grids of this sub grid

Parameters:

subGrid - subgrids

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

getDetails

public java.lang.String getDetails()

Returns textual details about the sub grid.

Returns:

textual details about the sub grid

getMaxLat

public double getMaxLat()

Get maximum latitude value

Returns:

maximum latitude

getMaxLon

public double getMaxLon()

Get maximum longitude value

Returns:

maximum longitude

getMinLat

public double getMinLat()

Get minimum latitude value

Returns:

minimum latitude

getMinLon

public double getMinLon()

Get minimum longitude value

Returns:

minimum longitude