HorizontalVerticalTransformation class final

Used to transform coordinates of z-aware geometries between spatial references that have different geographic and/or vertical coordinate systems.

A HorizontalVerticalTransformation is an ordered list of HorizontalVerticalTransformationStep objects. Each HorizontalVerticalTransformation has an input and an output SpatialReference, and this HorizontalVerticalTransformation object can be used to convert coordinates between the horizontal (geographic) and vertical datums of these spatial references using the series of steps it contains. Use the GeometryEngine.project method to transform the coordinates of a specific Geometry.

A horizontal transformation step is not needed when the input and output spatial references have the same underlying geographic coordinate systems. A vertical transformation is not needed if both datums (for ellipsoidal heights) or vertical datums (for gravity-related heights) are the same. To transform coordinates only between different horizontal (geographic) coordinate systems, you can use a GeographicTransformation instead.

The inverse of this transformation, used to transform in the opposite direction, is returned from the DatumTransformation.getInverse method.

A HorizontalVerticalTransformation can be constructed from a single HorizontalVerticalTransformationStep object, or from a number of transformation step objects that are chained together.

You can get a list of suitable transformations for a given input and output spatial reference using one of the methods on the TransformationCatalog class.

Some transformations require that certain Projection Engine data files be present on the local file system, and vertical transformation steps are especially likely to use such files, which can be very large in size. The DatumTransformation.isMissingProjectionEngineFiles property indicates whether any of the files are missing. The complete list of necessary files for each specific step is available using the HorizontalVerticalTransformationStep.projectionEngineFilenames property.

A HorizontalVerticalTransformation object is immutable.

Inheritance

Constructors

HorizontalVerticalTransformation.withStep(HorizontalVerticalTransformationStep step)
Create a single step transformation.
factory
HorizontalVerticalTransformation.withSteps(List<HorizontalVerticalTransformationStep> steps)
Create a multi-step transformation from one or more HorizontalVerticalTransformationStep instances.
factory

Properties

hashCode int
The hash code for this object.
no setterinherited
inputSpatialReference SpatialReference?
The input SpatialReference.
no setterinherited
isMissingProjectionEngineFiles bool
True if any files needed by the Projection Engine for this transformation step are missing from the local file system.
no setterinherited
name String
The name of the datum transformation.
no setterinherited
outputSpatialReference SpatialReference?
The output SpatialReference.
no setterinherited
runtimeType Type
A representation of the runtime type of the object.
no setterinherited
steps List<HorizontalVerticalTransformationStep>
The array of transformation steps that define this transformation.
no setter

Methods

getInverse() DatumTransformation
Returns the inverse of this datum transformation.
inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
toString() String
A string representation of this object.
inherited

Operators

operator ==(Object other) bool
The equality operator.
inherited