Module org.apache.sis.referencing
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:
-
Nested Class Summary
Nested classes/interfaces inherited from class AbstractMathTransform
AbstractMathTransform.Inverse -
Constructor Summary
ConstructorsModifierConstructorDescriptionprotectedPassThroughTransform(int firstAffectedCoordinate, MathTransform subTransform, int numTrailingCoordinates) Constructor for sub-classes. -
Method Summary
Modifier and TypeMethodDescriptionprotected intComputes a hash value for this transform.static MathTransformcreate(BitSet modifiedCoordinates, MathTransform subTransform, int resultDim, MathTransformFactory factory) Creates a transform which passes through a subset of coordinates to another transform.derivative(DirectPosition point) Gets the derivative of this transform at a point.booleanequals(Object object, ComparisonMode mode) Compares the specified object with this math transform for equality.protected StringFormats 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 intGets the dimension of input points.final MathTransformReturns the sub-transform to apply on the modified coordinates.final intGets the dimension of output points.inverse()Creates the inverse transform of this object.booleanTests 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.voidtransform(double[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts) Transforms many positions in a list of coordinate values.voidtransform(double[] srcPts, int srcOff, float[] dstPts, int dstOff, int numPts) Transforms many positions in a list of coordinate values.voidtransform(float[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts) Transforms many positions in a list of coordinate values.voidtransform(float[] srcPts, int srcOff, float[] dstPts, int dstOff, int numPts) Transforms many positions in a list of coordinate values.protected MathTransformtryConcatenate(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, getDomain, getParameterDescriptors, getParameterValues, hashCode, transformMethods inherited from class FormattableObject
print, toString, toString, toWKTMethods inherited from class Object
clone, finalize, getClass, notify, notifyAll, wait, wait, waitMethods 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 givensubTransformis not necessarily aPassThroughTransforminstance.- 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
-
create
public static MathTransform create(BitSet modifiedCoordinates, MathTransform subTransform, int resultDim, MathTransformFactory factory) throws FactoryException Creates a transform which passes through a subset of coordinates to another transform. The list of modified coordinates is specified by aBitSetargument where each bit set to 1 identifies the dimension of a modified coordinate. The array of modified coordinates can be expanded as below:The bitset cardinality, which is also the length of above array, must be equal to the number of source dimensions in the givenint[] modifiedCoordinates = bitset.stream().toArray();subTransform.Limitation
If the modified coordinates are not at consecutive positions in source coordinate tuples, then the current implementation of this method adds the following restrictions:- The sub-transform must have an number of target dimensions equal to the number of source dimensions.
- The sub-transform must be separable.
- Parameters:
modifiedCoordinates- positions in a source coordinate tuple of the coordinates affected by the transform.subTransform- the sub-transform to apply on modified coordinates.resultDim- total number of source dimensions of the pass-through transform to return.factory- the factory to use for creating transforms, ornullfor the default.- Returns:
- a pass-through transform for the given set of modified coordinates.
- Throws:
MismatchedDimensionException- if themodifiedCoordinatesbitset cardinality is not equal to the number of source dimensions insubTransform.IllegalArgumentException- if the index of a modified coordinates is out of bounds.FactoryException- if an error occurred while creating a transform step.- Since:
- 1.4
- See Also:
-
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:
getSourceDimensionsin interfaceMathTransform- Specified by:
getSourceDimensionsin classAbstractMathTransform- Returns:
- the number of dimensions 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:
getTargetDimensionsin interfaceMathTransform- Specified by:
getTargetDimensionsin classAbstractMathTransform- Returns:
- the number of dimensions 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.- 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. APassThroughTransformis identity if the sub-transform is also identity.- Specified by:
isIdentityin interfaceMathTransform- Overrides:
isIdentityin 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:
transformin classAbstractMathTransform- Parameters:
srcPts- the array containing the source coordinates (cannot benull).srcOff- the offset to the point to be transformed in the source array.dstPts- the array into which the transformed coordinates is returned. May be the same thansrcPts. May benullif only the derivative matrix is desired.dstOff- the offset to the location of the transformed point that is stored in the destination array.derivate-truefor computing the derivative, orfalseif not needed.- Returns:
- the matrix of the transform derivative at the given source position,
or
nullif thederivateargument 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:
transformin interfaceMathTransform- Overrides:
transformin 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:
transformin interfaceMathTransform- Overrides:
transformin 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:
transformin interfaceMathTransform- Overrides:
transformin 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:
transformin interfaceMathTransform- Overrides:
transformin 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:
derivativein interfaceMathTransform- Overrides:
derivativein classAbstractMathTransform- Parameters:
point- the coordinate tuple 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:
inversein interfaceMathTransform- Overrides:
inversein 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 singlePassThroughTransforminstance. - If the other transform discards some dimensions, verify if we still need a
PassThroughTransform.
- Overrides:
tryConcatenatein classAbstractMathTransform- Parameters:
applyOtherFirst-trueif the transformation order isotherfollowed bythis, orfalseif the transformation order isthisfollowed byother.other- the other math transform to (pre-)concatenate with this transform.factory- the factory which is (indirectly) invoking this method, ornullif none.- Returns:
- the simplified transform, or
nullif 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:
computeHashCodein 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:
equalsin interfaceLenientComparable- Overrides:
equalsin classAbstractMathTransform- Parameters:
object- the object to compare with this transform.mode- the strictness level of the comparison. Default toSTRICT.- Returns:
trueif 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_MTis 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 thisPassThroughTransformcannot be formatted as valid WKT 1 neither).- Overrides:
formatToin classAbstractMathTransform- Parameters:
formatter- the formatter to use.- Returns:
- the WKT element name, which is
"PassThrough_MT". - See Also:
-