Class PassThroughTransform
Object
FormattableObject
AbstractMathTransform
PassThroughTransform
- All Implemented Interfaces:
Serializable
,Parameterized
,LenientComparable
,MathTransform
Transform which passes through a subset of coordinates to another transform.
This allows transforms to operate on a subset of coordinate values.
Example: giving (latitude, longitude, height) coordinates,
PassThroughTransform
can convert the height values from feet to meters without affecting the latitude and
longitude values. Such transform can be built as below:
MathTransform feetToMetres = MathTransforms.linear(0.3048, 0); // One-dimensional conversion. MathTransform tr = MathTransforms.passThrough(2, feetToMetres, 0); // Three-dimensional conversion.
Immutability and thread safety
PassThroughTransform
is immutable and thread-safe if its subTransform is also
immutable and thread-safe.
Serialization
Serialized instances of this class are not guaranteed to be compatible with future SIS versions. Serialization should be used only for short term storage or RMI between applications running the same SIS version.- Since:
- 0.5
- See Also:
Defined in the sis-referencing
module
-
Nested Class Summary
Nested classes/interfaces inherited from class AbstractMathTransform
AbstractMathTransform.Inverse
-
Constructor Summary
ConstructorsModifierConstructorDescriptionprotected
PassThroughTransform
(int firstAffectedCoordinate, MathTransform subTransform, int numTrailingCoordinates) Constructor for sub-classes. -
Method Summary
Modifier and TypeMethodDescriptionprotected int
Computes a hash value for this transform.derivative
(DirectPosition point) Gets the derivative of this transform at a point.boolean
equals
(Object object, ComparisonMode mode) Compares the specified object with this math transform for equality.protected String
Formats this transform as a Well Known Text version 1 (WKT 1) element.final int[]
Returns the ordered sequence of positive integers defining the positions in a source coordinate tuple of the coordinates affected by this pass-through operation.final int
Gets the dimension of input points.final MathTransform
Returns the sub-transform to apply on the modified coordinates.final int
Gets the dimension of output points.inverse()
Creates the inverse transform of this object.boolean
Tests whether this transform does not move any points.transform
(double[] srcPts, int srcOff, double[] dstPts, int dstOff, boolean derivate) Transforms a single position in a list of coordinate values, and opportunistically computes the transform derivative if requested.void
transform
(double[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts) Transforms many positions in a list of coordinate values.void
transform
(double[] srcPts, int srcOff, float[] dstPts, int dstOff, int numPts) Transforms many positions in a list of coordinate values.void
transform
(float[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts) Transforms many positions in a list of coordinate values.void
transform
(float[] srcPts, int srcOff, float[] dstPts, int dstOff, int numPts) Transforms many positions in a list of coordinate values.protected MathTransform
tryConcatenate
(boolean applyOtherFirst, MathTransform other, MathTransformFactory factory) Concatenates or pre-concatenates in an optimized way this transform with the given transform, if possible.Methods inherited from class AbstractMathTransform
equals, getContextualParameters, getParameterDescriptors, getParameterValues, hashCode, transform
Methods inherited from class FormattableObject
print, toString, toString, toWKT
Methods inherited from class Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
Methods inherited from interface MathTransform
toWKT
-
Constructor Details
-
PassThroughTransform
protected PassThroughTransform(int firstAffectedCoordinate, MathTransform subTransform, int numTrailingCoordinates) Constructor for sub-classes. Users should invoke the staticMathTransforms.passThrough(int, MathTransform, int)
factory method instead, since the most optimal pass-through transform for the givensubTransform
is not necessarily aPassThroughTransform
instance.- Parameters:
firstAffectedCoordinate
- index of the first affected coordinate.subTransform
- the sub-transform to apply on modified coordinates.numTrailingCoordinates
- number of trailing coordinates to pass through.- See Also:
-
-
Method Details
-
getSourceDimensions
public final int getSourceDimensions()Gets the dimension of input points. This the source dimension of the sub-transform plus the number of pass-through dimensions.- Specified by:
getSourceDimensions
in interfaceMathTransform
- Specified by:
getSourceDimensions
in classAbstractMathTransform
- Returns:
- the dimension of input points.
- See Also:
-
getTargetDimensions
public final int getTargetDimensions()Gets the dimension of output points. This the target dimension of the sub-transform plus the number of pass-through dimensions.- Specified by:
getTargetDimensions
in interfaceMathTransform
- Specified by:
getTargetDimensions
in classAbstractMathTransform
- Returns:
- the dimension of output points.
- See Also:
-
getModifiedCoordinates
public final int[] getModifiedCoordinates()Returns the ordered sequence of positive integers defining the positions in a source coordinate tuple of the coordinates affected by this pass-through operation.API note: this method is final for now because most of Apache SIS code do not use themodifiedCoordinates
array. Instead, SIS uses thefirstAffectedCoordinate
andnumTrailingCoordinates
information provided to the constructor. Consequently overriding this method may be misleading since it would be ignored by SIS. We do not want to make the "really used" fields public in order to keep the flexibility to replace them by amodifiedCoordinates
array in a future SIS version.- Returns:
- Zero-based indices of the modified source coordinates.
- See Also:
-
getSubTransform
Returns the sub-transform to apply on the modified coordinates. This is often the sub-transform specified at construction time, but not necessarily.- Returns:
- the sub-transform.
- See Also:
-
isIdentity
public boolean isIdentity()Tests whether this transform does not move any points. APassThroughTransform
is identity if the sub-transform is also identity.- Specified by:
isIdentity
in interfaceMathTransform
- Overrides:
isIdentity
in classAbstractMathTransform
- Returns:
-
transform
public Matrix transform(double[] srcPts, int srcOff, double[] dstPts, int dstOff, boolean derivate) throws TransformException Transforms a single position in a list of coordinate values, and opportunistically computes the transform derivative if requested.- Specified by:
transform
in classAbstractMathTransform
- Parameters:
srcPts
- the array containing the source coordinate (can not benull
).srcOff
- the offset to the point to be transformed in the source array.dstPts
- the array into which the transformed coordinate is returned. May be the same thansrcPts
. May benull
if only the derivative matrix is desired.dstOff
- the offset to the location of the transformed point that is stored in the destination array.derivate
-true
for computing the derivative, orfalse
if not needed.- Returns:
- the matrix of the transform derivative at the given source position,
or
null
if thederivate
argument isfalse
. - Throws:
TransformException
- if the sub-transform failed.- See Also:
-
transform
public void transform(double[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts) throws TransformException Transforms many positions in a list of coordinate values.- Specified by:
transform
in interfaceMathTransform
- Overrides:
transform
in classAbstractMathTransform
- 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 thansrcPts
.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 the sub-transform failed.
-
transform
public void transform(float[] srcPts, int srcOff, float[] dstPts, int dstOff, int numPts) throws TransformException Transforms many positions in a list of coordinate values.- Specified by:
transform
in interfaceMathTransform
- Overrides:
transform
in classAbstractMathTransform
- 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 thansrcPts
.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 the sub-transform failed.
-
transform
public void transform(double[] srcPts, int srcOff, float[] dstPts, int dstOff, int numPts) throws TransformException Transforms many positions in a list of coordinate values.- Specified by:
transform
in interfaceMathTransform
- Overrides:
transform
in classAbstractMathTransform
- 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.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 the sub-transform failed.
-
transform
public void transform(float[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts) throws TransformException Transforms many positions in a list of coordinate values.- Specified by:
transform
in interfaceMathTransform
- Overrides:
transform
in classAbstractMathTransform
- 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.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 the sub-transform failed.
-
derivative
Gets the derivative of this transform at a point.- Specified by:
derivative
in interfaceMathTransform
- Overrides:
derivative
in classAbstractMathTransform
- Parameters:
point
- the coordinate point where to evaluate the derivative.- Returns:
- the derivative at the specified point (never
null
). - Throws:
TransformException
- if the sub-transform failed.
-
inverse
Creates the inverse transform of this object.- Specified by:
inverse
in interfaceMathTransform
- Overrides:
inverse
in classAbstractMathTransform
- Returns:
- Throws:
NoninvertibleTransformException
- if the sub-transform is not invertible.
-
tryConcatenate
protected MathTransform tryConcatenate(boolean applyOtherFirst, MathTransform other, MathTransformFactory factory) throws FactoryException Concatenates or pre-concatenates in an optimized way this transform with the given transform, if possible. This method applies the following special cases:- If the other transform is also a
PassThroughTransform
, then the two transforms may be merged in a singlePassThroughTransform
instance. - If the other transform discards some dimensions, verify if we still need a
PassThroughTransform
.
- Overrides:
tryConcatenate
in classAbstractMathTransform
- Parameters:
applyOtherFirst
-true
if the transformation order isother
followed bythis
, orfalse
if the transformation order isthis
followed byother
.other
- the other math transform to (pre-)concatenate with this transform.factory
- the factory which is (indirectly) invoking this method, ornull
if none.- Returns:
- the simplified transform, or
null
if no such optimization is available. - Throws:
FactoryException
- if an error occurred while combining the transforms.- Since:
- 1.0
- See Also:
- If the other transform is also a
-
computeHashCode
protected int computeHashCode()Computes a hash value for this transform. This method is invoked byAbstractMathTransform.hashCode()
when first needed.- Overrides:
computeHashCode
in classAbstractMathTransform
- Returns:
- the hash code value. This value may change between different execution of the Apache SIS library.
-
equals
Compares the specified object with this math transform for equality.- Specified by:
equals
in interfaceLenientComparable
- Overrides:
equals
in classAbstractMathTransform
- Parameters:
object
- the object to compare with this transform.mode
- the strictness level of the comparison. Default toSTRICT
.- Returns:
true
if the given object is considered equals to this math transform.- See Also:
-
formatTo
Formats this transform as a Well Known Text version 1 (WKT 1) element.Compatibility note:PassThrough_MT
is defined in the WKT 1 specification only. If the formatter convention is set to WKT 2, then this method silently uses the WKT 1 convention without raising an error (unless thisPassThroughTransform
can not be formatted as valid WKT 1 neither).- Overrides:
formatTo
in classAbstractMathTransform
- Parameters:
formatter
- the formatter to use.- Returns:
- the WKT element name, which is
"PassThrough_MT"
. - See Also:
-