org.geotools.referencing.operation.transform

Class PassThroughTransform

Object

Formattable

AbstractMathTransform

PassThroughTransform

All Implemented Interfaces:

Serializable, MathTransform

public class PassThroughTransform
extends AbstractMathTransform
implements Serializable

Transform which passes through a subset of ordinates to another transform. This allows transforms to operate on a subset of ordinates. For example, if you have (latitude,longitude,height) coordinates, then you may wish to convert the height values from feet to meters without affecting the latitude and longitude values.

Since:

2.0

Author:

Martin Desruisseaux (IRD)

See Also:

DimensionFilter, Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class AbstractMathTransform

AbstractMathTransform.Inverse

Field Summary

Fields

Modifier and Type	Field and Description
protected int	firstAffectedOrdinate Index of the first affected ordinate.
protected int	numTrailingOrdinates Number of unaffected ordinates after the affected ones.
protected MathTransform	subTransform The sub transform.

Fields inherited from class Formattable

SINGLE_LINE

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	PassThroughTransform(int firstAffectedOrdinate, MathTransform subTransform, int numTrailingOrdinates) Create a pass through transform.

Method Summary

Modifier and Type	Method and Description
static MathTransform	create(int firstAffectedOrdinate, MathTransform subTransform, int numTrailingOrdinates) Creates a transform which passes through a subset of ordinates to another transform.
Matrix	derivative(DirectPosition point) Gets the derivative of this transform at a point.
boolean	equals(Object object) Compares the specified object with this math transform for equality.
protected String	formatWKT(Formatter formatter) Format the inner part of a Well Known Text (WKT) element.
int[]	getModifiedCoordinates() Ordered sequence of positive integers defining the positions in a coordinate tuple of the coordinates affected by this pass-through transform.
int	getSourceDimensions() Gets the dimension of input points.
MathTransform	getSubTransform() Returns the sub transform.
int	getTargetDimensions() Gets the dimension of output points.
int	hashCode() Returns a hash value for this transform.
MathTransform	inverse() Creates the inverse transform of this object.
boolean	isIdentity() Tests whether this transform does not move any points.
void	transform(double[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts) Transforms a list of coordinate point ordinal values.
void	transform(float[] srcPts, int srcOff, float[] dstPts, int dstOff, int numPts) Transforms a list of coordinate point ordinal values.

Methods inherited from class AbstractMathTransform

createTransformedShape, derivative, ensureNonNull, getName, getParameterDescriptors, getParameterValues, needCopy, normalizeAngle, rollLongitude, transform, transform, transform, transform

Methods inherited from class Formattable

cleanupThreadLocals, toString, toWKT, toWKT, toWKT, toWKT

Methods inherited from class Object

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

Methods inherited from interface MathTransform

toWKT

Field Detail

firstAffectedOrdinate

protected final int firstAffectedOrdinate

Index of the first affected ordinate.

numTrailingOrdinates

protected final int numTrailingOrdinates

Number of unaffected ordinates after the affected ones. Always 0 when used through the strict OpenGIS API.

subTransform

protected final MathTransform subTransform

The sub transform.

See Also:

getSubTransform()

Constructor Detail

PassThroughTransform

protected PassThroughTransform(int firstAffectedOrdinate,
                               MathTransform subTransform,
                               int numTrailingOrdinates)

Create a pass through transform.

Parameters:

firstAffectedOrdinate - Index of the first affected ordinate.

subTransform - The sub transform.

numTrailingOrdinates - Number of trailing ordinates to pass through. Affected ordinates will range from firstAffectedOrdinate inclusive to dimTarget-numTrailingOrdinates exclusive.

Method Detail

create

public static MathTransform create(int firstAffectedOrdinate,
                                   MathTransform subTransform,
                                   int numTrailingOrdinates)

Creates a transform which passes through a subset of ordinates to another transform. This allows transforms to operate on a subset of ordinates. For example, if you have (latitidue,longitude,height) coordinates, then you may wish to convert the height values from feet to meters without affecting the latitude and longitude values.

Parameters:

firstAffectedOrdinate - Index of the first affected ordinate.

subTransform - The sub transform.

numTrailingOrdinates - Number of trailing ordinates to pass through. Affected ordinates will range from firstAffectedOrdinate inclusive to dimTarget-numTrailingOrdinates exclusive.

Returns:

A pass through transform with the following dimensions:

 Source: firstAffectedOrdinate + subTransform.getSourceDimensions() + numTrailingOrdinates
 Target: firstAffectedOrdinate + subTransform.getTargetDimensions() + numTrailingOrdinates

getSubTransform

public MathTransform getSubTransform()

Returns the sub transform.

Returns:

The sub transform.

Since:

2.2

getModifiedCoordinates

public int[] getModifiedCoordinates()

Ordered sequence of positive integers defining the positions in a coordinate tuple of the coordinates affected by this pass-through transform. The returned index are for source coordinates.

Returns:

The modified coordinates.

getSourceDimensions

public int getSourceDimensions()

Gets the dimension of input points.

Specified by:

getSourceDimensions in interface MathTransform

Specified by:

getSourceDimensions in class AbstractMathTransform

Returns:

The dimension of input points.

getTargetDimensions

public int getTargetDimensions()

Gets the dimension of output points.

Specified by:

getTargetDimensions in interface MathTransform

Specified by:

getTargetDimensions in class AbstractMathTransform

Returns:

The dimension of output points.

isIdentity

public boolean isIdentity()

Tests whether this transform does not move any points.

Specified by:

isIdentity in interface MathTransform

Overrides:

isIdentity in class AbstractMathTransform

Returns:

true if this MathTransform is an identity transform; false otherwise.

transform

public void transform(float[] srcPts,
                      int srcOff,
                      float[] dstPts,
                      int dstOff,
                      int numPts)
               throws TransformException

Transforms a list of coordinate point ordinal values.

Specified by:

transform in interface MathTransform

Overrides:

transform in class AbstractMathTransform

Parameters:

srcPts - the array containing the source point coordinates.

srcOff - the offset to the first point to be transformed in the source array.

dstPts - the array into which the transformed point coordinates are returned. May be the same than srcPts.

dstOff - the offset to the location of the first transformed point that is stored in the destination array.

numPts - the number of point objects to be transformed.

Throws:

TransformException - if a point can't be transformed. Some implementations will stop at the first failure, wile some other implementations will fill the untransformable points with NaN values, continue and throw the exception only at end. Implementations that fall in the later case should set the last completed transform to this.

transform

public void transform(double[] srcPts,
                      int srcOff,
                      double[] dstPts,
                      int dstOff,
                      int numPts)
               throws TransformException

Transforms a list of coordinate point ordinal values.

Specified by:

transform in interface MathTransform

Parameters:

srcPts - the array containing the source point coordinates.

srcOff - the offset to the first point to be transformed in the source array.

dstPts - the array into which the transformed point coordinates are returned. May be the same than srcPts.

dstOff - the offset to the location of the first transformed point that is stored in the destination array.

numPts - the number of point objects to be transformed.

Throws:

TransformException - if a point can't be transformed. Some implementations will stop at the first failure, wile some other implementations will fill the untransformable points with NaN values, continue and throw the exception only at end. Implementations that fall in the later case should set the last completed transform to this.

derivative

public Matrix derivative(DirectPosition point)
                  throws TransformException

Gets the derivative of this transform at a point.

Specified by:

derivative in interface MathTransform

Overrides:

derivative in class AbstractMathTransform

Parameters:

point - The coordinate point where to evaluate the derivative.

Returns:

The derivative at the specified point (never null).

Throws:

TransformException - if the derivative can't be evaluated at the specified point.

inverse

public MathTransform inverse()
                      throws NoninvertibleTransformException

Creates the inverse transform of this object.

Specified by:

inverse in interface MathTransform

Overrides:

inverse in class AbstractMathTransform

Returns:

The inverse transform.

Throws:

NoninvertibleTransformException - if the transform can't be inversed.

hashCode

public int hashCode()

Returns a hash value for this transform. This value need not remain consistent between different implementations of the same class.

Overrides:

hashCode in class AbstractMathTransform

equals

public boolean equals(Object object)

Compares the specified object with this math transform for equality.

Overrides:

equals in class AbstractMathTransform

Parameters:

object - The object to compare with this transform.

Returns:

true if the given object is a transform of the same class and if, given identical source position, the transformed position would be the equals.

formatWKT

protected String formatWKT(Formatter formatter)

Format the inner part of a Well Known Text (WKT) element.

Overrides:

formatWKT in class AbstractMathTransform

Parameters:

formatter - The formatter to use.

Returns:

The WKT element name.

See Also:

Formattable.toWKT(), Formattable.toString()