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GeographicTransformationStep Class


A step in the process of transforming between datums. More...

Header: #include <GeographicTransformationStep>
Since: Esri::ArcGISRuntime 100.2

Public Functions

GeographicTransformationStep(int wkid)
GeographicTransformationStep(const QString &wkText)
GeographicTransformationStep(const GeographicTransformationStep &other)
GeographicTransformationStep(GeographicTransformationStep &&other)
GeographicTransformationStep inverseTransformation() const
bool isEmpty() const
bool isInverse() const
bool isMissingProjectionEngineFiles() const
QStringList projectionEngineFilenames() const
QString wkText() const
int wkid() const
bool operator!=(const GeographicTransformationStep &other) const
GeographicTransformationStep &operator=(const GeographicTransformationStep &other)
GeographicTransformationStep &operator=(GeographicTransformationStep &&other)
bool operator==(const GeographicTransformationStep &other) const

Detailed Description

A step in the process of transforming between datums.

Each GeographicTransformationStep can be constructed from a well-known ID (WKID) that represents a geographic transformation. Because the Projection Engine supports thousands of transformations, WKIDs are not presented in the SDK as enumerations. Instead, they are documented in the ArcGIS Runtime SDK 100.4.0 for Qt documentation.

The list of supported WKIDs includes a transformation from every supported datum to WGS 1984. Additionally, there is more limited list of transformations that transform directly between two non-WGS84 datums, such as 4461, which is NAD_1983_HARN_To_NAD_1983_NSRS2007_1.

Transformations with more than one step typically go via WGS84, with one forward and one inverse geographic transformation chained together to get the required geographic coordinates.

A GeographicTransformationStep object is immutable.

Member Function Documentation


Default constructor.

GeographicTransformationStep::GeographicTransformationStep(int wkid)

Constructor that accepts the WKID (wkid) for the geographic transformation.

GeographicTransformationStep::GeographicTransformationStep(const QString &wkText)

Constructor that accepts the WKT (wkText) for the geographic transformation.

Use this constructor to specify a custom transformation, using WKT notation.

GeographicTransformationStep::GeographicTransformationStep(const GeographicTransformationStep &other)

Copy constructor from other GeographicTransformationStep.

GeographicTransformationStep::GeographicTransformationStep(GeographicTransformationStep &&other)

Move constructor from other GeographicTransformationStep.



GeographicTransformationStep GeographicTransformationStep::inverseTransformation() const

Returns a GeographicTransformationStep that is the inverse of this GeographicTransformationStep.

Returns empty GeographicTransformationStep if there is no inverse of this GeographicTransformationStep.

bool GeographicTransformationStep::isEmpty() const

Returns true if this geographic transformation step is empty.

bool GeographicTransformationStep::isInverse() const

Returns whether this geographic transformation step instance is an inverted transformation.

Returns true if this step uses the inverse of the geographic transformation contained in this step.

bool GeographicTransformationStep::isMissingProjectionEngineFiles() const

Returns whether any files needed by the Projection Engine for this GeographicTransformationStep are missing from the local file system.

QStringList GeographicTransformationStep::projectionEngineFilenames() const

Returns a list of the Projection Engine files required to support this step.

Each name in the list includes the full path.

Projection Engine datasets are used in grid-based transforms.

QString GeographicTransformationStep::wkText() const

Returns the Well-Known Text (WKT) representation of the geographic transformation in this step.

Returns an empty string if no WKT has been specified or if the geographic transformation is invalid.

This method always returns the minimal text representation that uniquely identifies a given geographic transformation.

int GeographicTransformationStep::wkid() const

Returns the Well-Known Identifier (WKID) of the geographic transformation in this step.

Returns -1 if no WKID has been specified.

bool GeographicTransformationStep::operator!=(const GeographicTransformationStep &other) const

Inequality operator. Returns true if this object and other are not equal.

See also GeographicTransformationStep::operator==.

GeographicTransformationStep &GeographicTransformationStep::operator=(const GeographicTransformationStep &other)

Assignment operator from other object.

GeographicTransformationStep &GeographicTransformationStep::operator=(GeographicTransformationStep &&other)

Move operator from other GeographicTransformationStep.

bool GeographicTransformationStep::operator==(const GeographicTransformationStep &other) const

Equivalency operator. Returns true if this object and other are equal.

This is the only valid way to compare two geographic transformation steps. Comparing individual attributes for two objects can return misleading results and should be avoided.

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