Package org.geotools.referencing.operation.transform

Class IdentityTransform

Object
Formattable
AbstractMathTransform
IdentityTransform
All Implemented Interfaces:
Serializable, MathTransform, LinearTransform
public class IdentityTransform extends AbstractMathTransform implements LinearTransform, Serializable
The identity transform. The data are only copied without any transformation. This class is used for identity transform of dimension greater than 2. For 1D and 2D identity transforms, LinearTransform1D and AffineTransform already provide their own optimisations.
Since:
2.0
Author:
Martin Desruisseaux (IRD)
See Also:

  • Constructor Details

    • IdentityTransform

      protected IdentityTransform(int dimension)
      Constructs an identity transform of the specified dimension.

  • Method Details

    • create

      public static LinearTransform create(int dimension)
      Constructs an identity transform of the specified dimension.

    • isIdentity

      public boolean isIdentity()
      Tests whether this transform does not move any points. This implementation always returns true.
      Specified by:
      isIdentity in interface MathTransform
      Overrides:
      isIdentity in class AbstractMathTransform
      Returns:
      true if this MathTransform is an identity transform; false otherwise.

    • isIdentity

      public boolean isIdentity(double tolerance)
      Tests whether this transform does not move any points. This implementation always returns true.
      Specified by:
      isIdentity in interface LinearTransform
      Parameters:
      tolerance - The tolerance factor.
      Returns:
      true if this transform is the identity one

    • 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.

    • getParameterDescriptors

      public ParameterDescriptorGroup getParameterDescriptors()
      Returns the parameter descriptors for this math transform.
      Overrides:
      getParameterDescriptors in class AbstractMathTransform
      Returns:
      The parameter descriptors for this math transform, or null.
      See Also:

    • getParameterValues

      public ParameterValueGroup getParameterValues()
      Returns the matrix elements as a group of parameters values.
      Overrides:
      getParameterValues in class AbstractMathTransform
      Returns:
      A copy of the parameter values for this math transform.
      See Also:

    • getMatrix

      public Matrix getMatrix()
      Returns a copy of the identity matrix.
      Specified by:
      getMatrix in interface LinearTransform
      Returns:
      A copy of the underlying matrix.

    • derivative

      public Matrix derivative(Position point)
      Gets the derivative of this transform at a point. For an identity transform, the derivative is the same everywhere.
      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).

    • transform

      public Position transform(Position ptSrc, Position ptDst)
      Copies the values from ptSrc to ptDst. Overrides the super-class method for performance reason.
      Specified by:
      transform in interface MathTransform
      Overrides:
      transform in class AbstractMathTransform
      Parameters:
      ptSrc - the specified coordinate point to be transformed.
      ptDst - the specified coordinate point that stores the result of transforming ptSrc, or null.
      Returns:
      the coordinate point after transforming ptSrc and storing the result in ptDst, or a newly created point if ptDst was null.
      Since:
      2.2

    • transform

      public void transform(float[] srcPts, int srcOff, float[] dstPts, int dstOff, int numPts)
      Transforms an array of floating point coordinates by this transform.
      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.

    • transform

      public void transform(double[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts)
      Transforms an array of floating point coordinates by this transform.
      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.

    • inverse

      public MathTransform inverse()
      Returns the inverse transform of this object, which is this transform itself
      Specified by:
      inverse in interface MathTransform
      Overrides:
      inverse in class AbstractMathTransform
      Returns:
      The inverse transform.

    • 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.