Module org.opengis.geoapi

Package org.opengis.referencing.operation

Interface MathTransform2D

All Superinterfaces:

MathTransform

public interface MathTransform2D
extends MathTransform

Transforms two-dimensional coordinate points. CoordinateOperation.getMathTransform() may returns instance of this interface when source and destination coordinate systems are both two dimensional. MathTransform2D extends MathTransform by adding some methods for easier inter-operability with Java2D.

Since:

1.0

Departure from OGC/ISO standard for closer integration with the Java environment

This interface is not part of OGC specification. It has been added in GeoAPI for close integration with the Java2D library. The API defined in this interface matches the java.awt.geom.AffineTransform API.

Method Summary

Modifier and Type	Method	Description
Shape	createTransformedShape(Shape shape)	Transforms the specified shape.
Matrix	derivative(Point2D point)	Gets the derivative of this transform at a point.
default int	getSourceDimensions()	Returns the number of dimensions of input points, which shall be 2.
default int	getTargetDimensions()	Returns the number of dimensions of output points, which shall be 2.
default MathTransform2D	inverse()	Returns the inverse transform of this object.
Point2D	transform(Point2D ptSrc, Point2D ptDst)	Transforms the specified ptSrc and stores the result in ptDst.

Methods inherited from interface org.opengis.referencing.operation.MathTransform

derivative, isIdentity, toWKT, transform, transform, transform, transform, transform, transform, transform, transform, transform

Method Details

getSourceDimensions

default int getSourceDimensions()

Returns the number of dimensions of input points, which shall be 2.

Specified by:

getSourceDimensions in interface MathTransform

Returns:

always 2.

getTargetDimensions

default int getTargetDimensions()

Returns the number of dimensions of output points, which shall be 2.

Specified by:

getTargetDimensions in interface MathTransform

Returns:

always 2.

transform

Point2D transform(Point2D ptSrc,
 Point2D ptDst)
           throws TransformException

Transforms the specified ptSrc and stores the result in ptDst. If ptDst is null, a new Point2D object is allocated and then the result of the transformation is stored in this object. In either case, ptDst, which contains the transformed point, is returned for convenience. If ptSrc and ptDst are the same object, the input point is correctly overwritten with the transformed point.

Parameters:

ptSrc - the coordinate point to be transformed.

ptDst - the coordinate point that stores the result of transforming ptSrc, or null if a new point shall be created.

Returns:

the coordinate point after transforming ptSrc and storing the result in ptDst or in a new point if ptDst was null.

Throws:

TransformException - if the point cannot be transformed.

See Also:

• AffineTransform.transform(Point2D, Point2D)

createTransformedShape

Shape createTransformedShape(Shape shape)
                      throws TransformException

Transforms the specified shape. This method may replace straight lines by quadratic curves when applicable. It may also do the opposite (replace curves by straight lines). The returned shape doesn't need to have the same number of points than the original shape.

Parameters:

shape - the Shape to transform.

Returns:

the transformed shape. Some implementations may return shape unmodified if this transform is identity.

Throws:

TransformException - if a transform failed.

See Also:

• AffineTransform.createTransformedShape(Shape)

derivative

Matrix derivative(Point2D point)
           throws TransformException

Gets the derivative of this transform at a point. The derivative is the matrix of the non-translating portion of the approximate affine map at the point.

Parameters:

point - the coordinate point where to evaluate the derivative. Null value is accepted only if the derivative is the same everywhere. For example, affine transform accept null value since they produces identical derivative no matter the coordinate value. But most map projection will requires a non-null value.

Returns:

the derivative at the specified point as a 2×2 matrix. This method never returns an internal object: changing the matrix will not change the state of this math transform.

Throws:

NullPointerException - if the derivative dependents on coordinate and point is null.

TransformException - if the derivative cannot be evaluated at the specified point.

inverse

default MathTransform2D inverse()
                         throws NoninvertibleTransformException

Returns the inverse transform of this object.

Specified by:

inverse in interface MathTransform

Returns:

the inverse transform.

Throws:

NoninvertibleTransformException - if the transform cannot be inverted.

See Also:

• AffineTransform.createInverse()