SpatialReference Class

Member Function Documentation

SpatialReference::SpatialReference(Esri::ArcGISRuntime::SpatialReference &&other)

Move constructor from other SpatialReference.

SpatialReference::SpatialReference(const Esri::ArcGISRuntime::SpatialReference &other)

Copy constructor from other SpatialReference.

SpatialReference::SpatialReference(int wkid, int verticalWkid)

Constructor using a wkid (well-known ID) that represents the spatial reference and a verticalWkid (vertical coordinate system well-known ID).

SpatialReference::SpatialReference(int wkid)

Constructor using a wkid (well-known ID) that represents the spatial reference.

Tolerance is set to 0.0.

SpatialReference::SpatialReference(const QString &wkText)

Constructor using a wkText (well-known text string) that represents the spatial reference.

The wkid property is also initialized based on the provided wkText. You can use a wkText extracted from another SpatialReference. If the wkText parameter is a null or empty string, this method creates an empty SpatialReference.

SpatialReference::SpatialReference()

Default constructor. Constructs an empty SpatialReference object.

The WKID and vertical WKID are set to -1 and the WKT is set to an empty string.

Esri::ArcGISRuntime::SpatialReference &SpatialReference::operator=(Esri::ArcGISRuntime::SpatialReference &&other)

Move operator from other SpatialReference.

Esri::ArcGISRuntime::SpatialReference &SpatialReference::operator=(const Esri::ArcGISRuntime::SpatialReference &other)

Assignment operator from other SpatialReference.

[override virtual] SpatialReference::~SpatialReference()

Destructor.

Esri::ArcGISRuntime::SpatialReference SpatialReference::baseGeographic() const

Returns the base geographic coordinate system if this is a projected coordinate system.

double SpatialReference::convergenceAngle(const Esri::ArcGISRuntime::Point &point) const

Returns the grid convergence in degrees for a spatial reference at a given point.

The grid convergence is the angle between True North and Grid North at a point on a map. The grid convergence can be used to convert a horizontal direction expressed as an azimuth in a geographic coordinate system (relative to True North) to a direction expressed as a bearing in a projected coordinate system (relative to Grid North), and vice versa.

Sign convention

The grid convergence returned by this method is positive when Grid North lies east of True North. The following formula demonstrates how to obtain a bearing (b) from an azimuth (a) using the grid convergence (c) returned by this method:

b = a - c

This sign convention is sometimes named the Gauss-Bomford convention.

Other notes

• Returns 0 if the spatial reference is a geographic coordinate system.
• Returns NAN if the point is outside the projection's horizon or on error.
• If the point has no spatial reference, it is assumed to be in the given spatial reference.
• If the point's spatial reference differs from the spatial reference given, its location is transformed automatically to the given spatial reference.

This function was introduced in Esri::ArcGISRuntime 100.3.

[static] Esri::ArcGISRuntime::SpatialReference SpatialReference::fromJson(const QString &json)

Creates a new SpatialReference from an ArcGIS JSON representation.

• json - The JSON text.

bool SpatialReference::hasVertical() const

Returns true if spatial reference has a vertical coordinate system set; false otherwise.

A spatial reference can optionally include a definition for a vertical coordinate system (VCS), which can be used to interpret the z-values of a geometry. A VCS defines linear units of measure, the origin of z-values, and whether z-values are "positive up" (representing heights above a surface) or "positive down" (indicating that values are depths below a surface).

A SpatialReference may have a VCS set, for example by calling the SpatialReference::SpatialReference(int, int) constructor. SpatialReference::verticalWkid, SpatialReference::wkText, and SpatialReference::verticalUnit provide more information about the specific VCS set on this instance.

VCSs are used when projecting geometries using a HorizontalVerticalTransformation.

This function was introduced in Esri::ArcGISRuntime 100.9.

See also SpatialReference::verticalWkid and SpatialReference::verticalUnit.

bool SpatialReference::isEmpty() const

Returns true if this SpatialReference is empty.

bool SpatialReference::isGeographic() const

Returns true if this is a geographic coordinate system.

bool SpatialReference::isPannable() const

Returns true if this SpatialReference supports wrap around.

bool SpatialReference::isProjected() const

Returns true if this SpatialReference is a projected coordinate system.

[override virtual] QString SpatialReference::toJson() const

Reimplements: JsonSerializable::toJson() const.

Returns this SpatialReference as an ArcGIS json SpatialReference representation.

Esri::ArcGISRuntime::Unit SpatialReference::unit() const

The unit of measure for the horizontal coordinate system of this spatial reference.

Returns a null Unit if the spatial reference is invalid.

[override virtual] QJsonObject SpatialReference::unknownJson() const

Reimplements: JsonSerializable::unknownJson() const.

Gets the unknown JSON of this object.

See also JsonSerializable.

[override virtual] QJsonObject SpatialReference::unsupportedJson() const

Reimplements: JsonSerializable::unsupportedJson() const.

Gets the unsupported JSON of this object.

See also JsonSerializable.

Esri::ArcGISRuntime::LinearUnit SpatialReference::verticalUnit() const

Returns the unit of measure for the vertical coordinate system of this spatial reference. Will return an empty unit if hasVertical is false.

This function was introduced in Esri::ArcGISRuntime 100.14.

int SpatialReference::verticalWkid() const

Returns the vertical coordinate system well-known spatial reference identifier (WKID).

The well-known ID for the vertical coordinate system (VCS), or 0 if the spatial reference has no VCS or has a custom VCS.

Note: In versions prior to Esri::ArcGISRuntime 100.9. This method returned -1 if no vertical WKID had been specified.

[static] Esri::ArcGISRuntime::SpatialReference SpatialReference::webMercator()

Returns a spatial reference representing the WebMercator coordinate system (WKID:102100)

[static] Esri::ArcGISRuntime::SpatialReference SpatialReference::wgs84()

Returns a spatial reference representing the WGS84 coordinate system (WKID:4326).

QString SpatialReference::wkText() const

Returns the well-known text representation.

Returns the well-known text for the horizontal and vertical coordinate system. Returns an empty string if no WKT has been specified or if the SpatialReference is invalid.

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

int SpatialReference::wkid() const

Returns the well-known spatial reference identifier (WKID).

The well-known ID for the horizontal coordinate system, or 0 if the spatial reference has a custom horizontal coordinate system. Returns 0 if no WKID has been specified.

Note: In versions prior to Esri::ArcGISRuntime 100.9. This method returned -1 if no WKID had been specified.

bool SpatialReference::operator!=(const Esri::ArcGISRuntime::SpatialReference &other) const

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

See also SpatialReference::operator==.

bool SpatialReference::operator==(const Esri::ArcGISRuntime::SpatialReference &other) const

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

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