org.apache.sis.referencing.operation.transform (Apache SIS referencing 0.6 API)

Interface Summary
Interface	Description
LinearTransform	A usually affine, or otherwise a projective transform, which convert coordinates using only linear equations.
MathTransformProvider	An object capable to create `MathTransform` instances from given parameter values.

Class Summary
Class	Description
AbstractMathTransform	Provides a default implementation for most methods required by the `MathTransform` interface.
AbstractMathTransform1D	Base class for math transforms that are known to be one-dimensional in all cases.
AbstractMathTransform2D	Base class for math transforms that are known to be two-dimensional in all cases.
ContextualParameters	The parameters that describe a sequence of normalize → non-linear kernel → denormalize transforms as a whole.
DefaultMathTransformFactory	Low level factory for creating math transforms.
MathTransforms	Utility methods creating or working on `MathTransform` instances.
PassThroughTransform	Transform which passes through a subset of ordinates to another transform.
TransferFunction	The function converting raster sample values to geophysics values.

Enum Summary
Enum Description

IterationStrategy
Strategy for iterating over the point arrays given to AbstractMathTransform.transform(…) methods.

Enum Summary
Enum	Description
IterationStrategy	Strategy for iterating over the point arrays given to `AbstractMathTransform.transform(…)` methods.

Package org.apache.sis.referencing.operation.transform Description

Conversions or transformations of multi-dimensional coordinate points. MathTransform provides a single API for coordinate conversions or transformations, including map projections. Each MathTransform instances can:

transform a single point,
transform efficiently an array of coordinates,
transform a Java2D Shape (MathTransform2D only),
compute the transform derivative at a location (for advanced users),
be concatenated in a conversion or transformation chain.

MathTransform are truly n-dimensional, but specialized implementations for 1D and 2D cases are provided for performance reasons or for inter-operability with Java2D. In the 2D case, Apache SIS provides instances of the standard AffineTransform class when possible.

This package does not include map projections, which are a special kind of transforms defined in their own projection package.

Creating math transforms

MathTransform instances can be created either directly or indirectly. The recommended way is the indirect one: first find the coordinate operation (generally from a pair of source and target CRS), then invoke CoordinateOperation.getMathTransform(). However sophisticated users can also create math transforms explicitely from a group of parameter values using the math transform factory.

Non-spatial coordinates

MathTransform usually performs conversions or transformations from points given in a source coordinate reference system to coordinate values for the same points in the target coordinate reference system. However the conversions are not necessarily between CRS; a MathTransform can also be used for converting the sample values in a raster for example. Such kind of transforms are named transfer functions.

Since:: 0.5