QgsProjUtils Class Reference

Utility functions for working with the proj library. More...

#include <qgsprojutils.h>

Classes
struct	ProjPJDeleter
	Destroys Proj PJ objects. More...

Public Types
enum	IdentifyFlag { FlagMatchBoundCrsToUnderlyingSourceCrs = 1 << 0 }
	Flags controlling CRS identification behavior. More...
using	proj_pj_unique_ptr = std::unique_ptr< PJ, ProjPJDeleter >
	Scoped Proj PJ object. More...

Static Public Member Functions
static bool	axisOrderIsSwapped (const PJ *crs)
	Returns true if the given proj coordinate system uses requires y/x coordinate order instead of x/y. More...
static bool	coordinateOperationIsAvailable (const QString &projDef)
	Returns true if a coordinate operation (specified via proj string) is available. More...
static proj_pj_unique_ptr	crsToDatumEnsemble (const PJ *crs)
	Given a PROJ crs, attempt to retrieve the datum ensemble from it. More...
static proj_pj_unique_ptr	crsToSingleCrs (const PJ *crs)
	Given a PROJ crs (which may be a compound or bound crs, or some other type), extract a single crs from it. More...
static QDate	epsgRegistryDate ()
	Returns the EPSG registry database release date used by the proj library. More...
static QString	epsgRegistryVersion ()
	Returns the EPSG registry database version used by the proj library (e.g. More...
static QDate	esriDatabaseDate ()
	Returns the ESRI projection engine database release date used by the proj library. More...
static QString	esriDatabaseVersion ()
	Returns the ESRI projection engine database version used by the proj library (e.g. More...
static QList< QgsDatumTransform::GridDetails >	gridsUsed (const QString &proj)
	Returns a list of grids used by the given proj string. More...
static bool	identifyCrs (const PJ *crs, QString &authName, QString &authCode, IdentifyFlags flags=IdentifyFlags())
	Attempts to identify a crs, matching it to a known authority and code within an acceptable level of tolerance. More...
static QDate	ignfDatabaseDate ()
	Returns the IGNF database release date used by the proj library. More...
static QString	ignfDatabaseVersion ()
	Returns the IGNF database version used by the proj library (e.g. More...
static bool	isDynamic (const PJ *crs)
	Returns true if the given proj coordinate system is a dynamic CRS. More...
static int	projVersionMajor ()
	Returns the proj library major version number. More...
static int	projVersionMinor ()
	Returns the proj library minor version number. More...
static QStringList	searchPaths ()
	Returns the current list of Proj file search paths. More...
static bool	usesAngularUnit (const QString &projDef)
	Returns true if the given proj coordinate system uses angular units. More...

Detailed Description

Utility functions for working with the proj library.

Since

QGIS 3.8

Definition at line 44 of file qgsprojutils.h.

Member Typedef Documentation

proj_pj_unique_ptr

using QgsProjUtils::proj_pj_unique_ptr = std::unique_ptr< PJ, ProjPJDeleter >

Scoped Proj PJ object.

Definition at line 141 of file qgsprojutils.h.

Member Enumeration Documentation

IdentifyFlag

enum QgsProjUtils::IdentifyFlag

Flags controlling CRS identification behavior.

Enumerator
FlagMatchBoundCrsToUnderlyingSourceCrs	Allow matching a BoundCRS object to its underlying SourceCRS.

Definition at line 119 of file qgsprojutils.h.

Member Function Documentation

axisOrderIsSwapped()

bool QgsProjUtils::axisOrderIsSwapped ( const PJ *  crs )

static

Returns true if the given proj coordinate system uses requires y/x coordinate order instead of x/y.

Definition at line 111 of file qgsprojutils.cpp.

coordinateOperationIsAvailable()

bool QgsProjUtils::coordinateOperationIsAvailable ( const QString &  projDef )

static

Returns true if a coordinate operation (specified via proj string) is available.

Definition at line 288 of file qgsprojutils.cpp.

crsToDatumEnsemble()

QgsProjUtils::proj_pj_unique_ptr QgsProjUtils::crsToDatumEnsemble ( const PJ *  crs )

static

Given a PROJ crs, attempt to retrieve the datum ensemble from it.

Warning

This method requires PROJ 8.0 or later

Exceptions

QgsNotSupportedException

on QGIS builds based on PROJ 7 or earlier.

Since

QGIS 3.20

Definition at line 217 of file qgsprojutils.cpp.

crsToSingleCrs()

QgsProjUtils::proj_pj_unique_ptr QgsProjUtils::crsToSingleCrs ( const PJ *  crs )

static

Given a PROJ crs (which may be a compound or bound crs, or some other type), extract a single crs from it.

Definition at line 183 of file qgsprojutils.cpp.

epsgRegistryDate()

QDate QgsProjUtils::epsgRegistryDate ( )

static

Returns the EPSG registry database release date used by the proj library.

See also

epsgRegistryVersion()

Since

QGIS 3.20

Definition at line 372 of file qgsprojutils.cpp.

epsgRegistryVersion()

QString QgsProjUtils::epsgRegistryVersion ( )

static

Returns the EPSG registry database version used by the proj library (e.g.

"v9.8.6").

See also

epsgRegistryDate()

Since

QGIS 3.20

Definition at line 365 of file qgsprojutils.cpp.

esriDatabaseDate()

QDate QgsProjUtils::esriDatabaseDate ( )

static

Returns the ESRI projection engine database release date used by the proj library.

See also

esriDatabaseVersion()

Since

QGIS 3.20

Definition at line 386 of file qgsprojutils.cpp.

esriDatabaseVersion()

QString QgsProjUtils::esriDatabaseVersion ( )

static

Returns the ESRI projection engine database version used by the proj library (e.g.

"ArcMap 10.8.0").

See also

esriDatabaseDate()

Since

QGIS 3.20

Definition at line 379 of file qgsprojutils.cpp.

gridsUsed()

QList< QgsDatumTransform::GridDetails > QgsProjUtils::gridsUsed ( const QString &  proj )

static

Returns a list of grids used by the given proj string.

Definition at line 301 of file qgsprojutils.cpp.

identifyCrs()

bool QgsProjUtils::identifyCrs ( const PJ *  crs, QString &  authName, QString &  authCode, IdentifyFlags  flags = IdentifyFlags()  )

static

Attempts to identify a crs, matching it to a known authority and code within an acceptable level of tolerance.

Returns true if a matching authority and code was found.

Definition at line 234 of file qgsprojutils.cpp.

ignfDatabaseDate()

QDate QgsProjUtils::ignfDatabaseDate ( )

static

Returns the IGNF database release date used by the proj library.

See also

ignfDatabaseVersion()

Since

QGIS 3.20

Definition at line 400 of file qgsprojutils.cpp.

ignfDatabaseVersion()

QString QgsProjUtils::ignfDatabaseVersion ( )

static

Returns the IGNF database version used by the proj library (e.g.

"3.1.0").

See also

ignfDatabaseDate()

Since

QGIS 3.20

Definition at line 393 of file qgsprojutils.cpp.

isDynamic()

bool QgsProjUtils::isDynamic ( const PJ *  crs )

static

Returns true if the given proj coordinate system is a dynamic CRS.

A dynamic CRS relies on a dynamic datum, that is a datum that is not plate-fixed.

Since

QGIS 3.20

Definition at line 142 of file qgsprojutils.cpp.

projVersionMajor()

int QgsProjUtils::projVersionMajor ( )

static

Returns the proj library major version number.

Definition at line 355 of file qgsprojutils.cpp.

projVersionMinor()

int QgsProjUtils::projVersionMinor ( )

static

Returns the proj library minor version number.

Since

QGIS 3.20

Definition at line 360 of file qgsprojutils.cpp.

searchPaths()

QStringList QgsProjUtils::searchPaths ( )

static

Returns the current list of Proj file search paths.

Note

Only available on builds based on Proj >= 6.0. Builds based on earlier Proj versions will always return an empty list.

Definition at line 407 of file qgsprojutils.cpp.

usesAngularUnit()

bool QgsProjUtils::usesAngularUnit ( const QString &  projDef )

static

Returns true if the given proj coordinate system uses angular units.

projDef must be a proj string defining a CRS object.

Definition at line 72 of file qgsprojutils.cpp.

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The documentation for this class was generated from the following files:

• /build/qgis-3.28.0+99sid/src/core/proj/qgsprojutils.h
• /build/qgis-3.28.0+99sid/src/core/proj/qgsprojutils.cpp