Class for doing transforms between two map coordinate systems. More...

#include <qgscoordinatetransform.h>

Inheritance diagram for QgsCoordinateTransform:

Public Types
enum	TransformDirection { ForwardTransform, ReverseTransform }
	Enum used to indicate the direction (forward or inverse) of the transform. More...

Public Slots
void	initialise ()
	initialize is used to actually create the Transformer instance More...

bool	readXML (QDomNode &theNode)
	Restores state from the given Dom node. More...

bool	writeXML (QDomNode &theNode, QDomDocument &theDoc)
	Stores state to the given Dom node in the given document. More...

Signals
void	invalidTransformInput () const
	Signal when an invalid pj_transform() has occurred. More...

Public Member Functions
	QgsCoordinateTransform ()
	Default constructor. More...

	QgsCoordinateTransform (const QgsCoordinateReferenceSystem &theSource, const QgsCoordinateReferenceSystem &theDest)
	Constructs a QgsCoordinateTransform using QgsCoordinateReferenceSystem objects. More...

	QgsCoordinateTransform (long theSourceSrsId, long theDestSrsId)
	Constructs a QgsCoordinateTransform using CRS ID of source and destination CRS. More...

	QgsCoordinateTransform (const QString &theSourceWkt, const QString &theDestWkt)

	QgsCoordinateTransform (long theSourceSrid, const QString &theDestWkt, QgsCoordinateReferenceSystem::CrsType theSourceCRSType=QgsCoordinateReferenceSystem::PostgisCrsId)

	~QgsCoordinateTransform ()
	destructor More...

QgsCoordinateTransform *	clone () const

const QgsCoordinateReferenceSystem &	destCRS () const

int	destinationDatumTransform () const

bool	isInitialised () const

bool	isShortCircuited () const
	See if the transform short circuits because src and dest are equivalent. More...

void	setDestCRS (const QgsCoordinateReferenceSystem &theCRS)

void	setDestCRSID (long theCRSID)
	Change the destination coordinate system by passing it a qgis srsid A QGIS srsid is a unique key value to an entry on the tbl_srs in the srs.db sqlite database. More...

void	setDestinationDatumTransform (int dt)

void	setSourceCrs (const QgsCoordinateReferenceSystem &theCRS)

void	setSourceDatumTransform (int dt)

const QgsCoordinateReferenceSystem &	sourceCrs () const

int	sourceDatumTransform () const

QgsPoint	transform (const QgsPoint &p, TransformDirection direction=ForwardTransform) const
	Transform the point from Source Coordinate System to Destination Coordinate System If the direction is ForwardTransform then coordinates are transformed from layer CS –> map canvas CS, otherwise points are transformed from map canvas CS to layerCS. More...

QgsPoint	transform (const double x, const double y, TransformDirection direction=ForwardTransform) const
	Transform the point specified by x,y from Source Coordinate System to Destination Coordinate System If the direction is ForwardTransform then coordinates are transformed from layer CS –> map canvas CS, otherwise points are transformed from map canvas CS to layerCS. More...

QgsRectangle	transform (const QgsRectangle &theRect, TransformDirection direction=ForwardTransform) const
	Transform a QgsRectangle to the dest Coordinate system If the direction is ForwardTransform then coordinates are transformed from layer CS –> map canvas CS, otherwise points are transformed from map canvas CS to layerCS. More...

QgsRectangle	transformBoundingBox (const QgsRectangle &theRect, TransformDirection direction=ForwardTransform, const bool handle180Crossover=false) const
	Transform a QgsRectangle to the dest Coordinate system If the direction is ForwardTransform then coordinates are transformed from layer CS –> map canvas CS, otherwise points are transformed from map canvas CS to layerCS. More...

void	transformCoords (int numPoint, double x, double y, double *z, TransformDirection direction=ForwardTransform) const
	Transform an array of coordinates to a different Coordinate System If the direction is ForwardTransform then coordinates are transformed from layer CS –> map canvas CS, otherwise points are transformed from map canvas CS to layerCS. More...

void	transformInPlace (double &x, double &y, double &z, TransformDirection direction=ForwardTransform) const

void	transformInPlace (float &x, float &y, double &z, TransformDirection direction=ForwardTransform) const

void	transformInPlace (float &x, float &y, float &z, TransformDirection direction=ForwardTransform) const

void	transformInPlace (QVector< float > &x, QVector< float > &y, QVector< float > &z, TransformDirection direction=ForwardTransform) const

void	transformInPlace (QVector< double > &x, QVector< double > &y, QVector< double > &z, TransformDirection direction=ForwardTransform) const

void	transformPolygon (QPolygonF &poly, TransformDirection direction=ForwardTransform) const

Public Member Functions inherited from QObject
	QObject (QObject *parent)

	QObject (QObject parent, const char name)

virtual	~QObject ()

bool	blockSignals (bool block)

QObject *	child (const char objName, const char inheritsClass, bool recursiveSearch) const

const QObjectList &	children () const

const char *	className () const

bool	connect (const QObject sender, const char signal, const char *method, Qt::ConnectionType type) const

void	deleteLater ()

void	destroyed (QObject *obj)

bool	disconnect (const QObject receiver, const char method)

bool	disconnect (const char signal, const QObject receiver, const char *method)

void	dumpObjectInfo ()

void	dumpObjectTree ()

QList< QByteArray >	dynamicPropertyNames () const

virtual bool	event (QEvent *e)

virtual bool	eventFilter (QObject watched, QEvent event)

T	findChild (const QString &name) const

QList< T >	findChildren (const QRegExp &regExp) const

QList< T >	findChildren (const QString &name) const

bool	inherits (const char *className) const

void	insertChild (QObject *object)

void	installEventFilter (QObject *filterObj)

bool	isA (const char *className) const

bool	isWidgetType () const

void	killTimer (int id)

virtual const QMetaObject *	metaObject () const

void	moveToThread (QThread *targetThread)

const char *	name () const

const char *	name (const char *defaultName) const

QString	objectName () const

QObject *	parent () const

QVariant	property (const char *name) const

void	removeChild (QObject *object)

void	removeEventFilter (QObject *obj)

void	setName (const char *name)

void	setObjectName (const QString &name)

void	setParent (QObject *parent)

bool	setProperty (const char *name, const QVariant &value)

bool	signalsBlocked () const

int	startTimer (int interval)

QThread *	thread () const

Static Public Member Functions
static QList< QList< int > >	datumTransformations (const QgsCoordinateReferenceSystem &srcCRS, const QgsCoordinateReferenceSystem &destCRS)
	Returns list of datum transformations for the given src and dest CRS. More...

static bool	datumTransformCrsInfo (int datumTransform, int &epsgNr, QString &srcProjection, QString &dstProjection, QString &remarks, QString &scope, bool &preferred, bool &deprecated)
	Gets name of source and dest geographical CRS (to show in a tooltip) More...

static QString	datumTransformString (int datumTransform)

Static Public Member Functions inherited from QObject
bool	connect (const QObject sender, const char signal, const QObject receiver, const char method, Qt::ConnectionType type)

bool	connect (const QObject sender, const QMetaMethod &signal, const QObject receiver, const QMetaMethod &method, Qt::ConnectionType type)

bool	disconnect (const QObject sender, const char signal, const QObject receiver, const char method)

bool	disconnect (const QObject sender, const QMetaMethod &signal, const QObject receiver, const QMetaMethod &method)

QString	tr (const char sourceText, const char disambiguation, int n)

QString	trUtf8 (const char sourceText, const char disambiguation, int n)

Additional Inherited Members
Protected Member Functions inherited from QObject
bool	checkConnectArgs (const char signal, const QObject object, const char *method)

virtual void	childEvent (QChildEvent *event)

virtual void	connectNotify (const char *signal)

virtual void	customEvent (QEvent *event)

virtual void	disconnectNotify (const char *signal)

int	receivers (const char *signal) const

QObject *	sender () const

int	senderSignalIndex () const

virtual void	timerEvent (QTimerEvent *event)

Static Protected Member Functions inherited from QObject
QByteArray	normalizeSignalSlot (const char *signalSlot)

Properties inherited from QObject
	objectName

Detailed Description

Class for doing transforms between two map coordinate systems.

This class can convert map coordinates to a different coordinate reference system. It is normally associated with a map layer and is used to transform between the layer's coordinate system and the coordinate system of the map canvas, although it can be used in a more general sense to transform coordinates.

All references to source and destination coordinate systems refer to layer and map canvas respectively. All operations are from the perspective of the layer. For example, a forward transformation transforms coordinates from the layers coordinate system to the map canvas.

Definition at line 55 of file qgscoordinatetransform.h.

Member Enumeration Documentation

◆ TransformDirection

enum QgsCoordinateTransform::TransformDirection

Enum used to indicate the direction (forward or inverse) of the transform.

Enumerator
ForwardTransform	Transform from source to destination CRS.
ReverseTransform	Transform from destination to source CRS.

Definition at line 97 of file qgscoordinatetransform.h.

Constructor & Destructor Documentation

◆ QgsCoordinateTransform() [1/5]

QgsCoordinateTransform::QgsCoordinateTransform ( )

Default constructor.

Make sure you use initialized() manually if you use this one!

Definition at line 42 of file qgscoordinatetransform.cpp.

◆ QgsCoordinateTransform() [2/5]

QgsCoordinateTransform::QgsCoordinateTransform	(	const QgsCoordinateReferenceSystem &	theSource,
		const QgsCoordinateReferenceSystem &	theDest
	)

Constructs a QgsCoordinateTransform using QgsCoordinateReferenceSystem objects.

Parameters

theSource	CRS, typically of the layer's coordinate system
theDest	CRS, typically of the map canvas coordinate system

Definition at line 52 of file qgscoordinatetransform.cpp.

◆ QgsCoordinateTransform() [3/5]

QgsCoordinateTransform::QgsCoordinateTransform	(	long	theSourceSrsId,
		long	theDestSrsId
	)

Constructs a QgsCoordinateTransform using CRS ID of source and destination CRS.

Definition at line 65 of file qgscoordinatetransform.cpp.

◆ QgsCoordinateTransform() [4/5]

QgsCoordinateTransform::QgsCoordinateTransform	(	const QString &	theSourceWkt,
		const QString &	theDestWkt
	)

Constructs a QgsCoordinateTransform using the Well Known Text representation of the layer and map canvas coordinate systems

Parameters

theSourceWkt	Wkt, typically of the layer's coordinate system
theDestWkt	Wkt, typically of the map canvas coordinate system

Definition at line 76 of file qgscoordinatetransform.cpp.

◆ QgsCoordinateTransform() [5/5]

QgsCoordinateTransform::QgsCoordinateTransform	(	long	theSourceSrid,
		const QString &	theDestWkt,
		QgsCoordinateReferenceSystem::CrsType	theSourceCRSType = `QgsCoordinateReferenceSystem::PostgisCrsId`
	)

Constructs a QgsCoordinateTransform using a Spatial Reference Id of the layer and map canvas coordinate system as Wkt

Parameters

theSourceSrid	Spatial Ref Id of the layer's coordinate system
theDestWkt	Wkt of the map canvas coordinate system
theSourceCRSType	On of the enum members defined in QgsCoordinateReferenceSystem::CrsType

Definition at line 92 of file qgscoordinatetransform.cpp.

◆ ~QgsCoordinateTransform()

QgsCoordinateTransform::~QgsCoordinateTransform ( )

destructor

Definition at line 111 of file qgscoordinatetransform.cpp.

Member Function Documentation

◆ clone()

QgsCoordinateTransform * QgsCoordinateTransform::clone ( ) const

Definition at line 116 of file qgscoordinatetransform.cpp.

◆ datumTransformations()

QList< QList< int > > QgsCoordinateTransform::datumTransformations	(	const QgsCoordinateReferenceSystem &	srcCRS,
		const QgsCoordinateReferenceSystem &	destCRS
	)

static

Returns list of datum transformations for the given src and dest CRS.

Note: not available in python bindings

Definition at line 800 of file qgscoordinatetransform.cpp.

◆ datumTransformCrsInfo()

bool QgsCoordinateTransform::datumTransformCrsInfo	(	int	datumTransform,
		int &	epsgNr,
		QString &	srcProjection,
		QString &	dstProjection,
		QString &	remarks,
		QString &	scope,
		bool &	preferred,
		bool &	deprecated
	)

static

Gets name of source and dest geographical CRS (to show in a tooltip)

Returns: epsgNr epsg code of the transformation (or 0 if not in epsg db)

Definition at line 973 of file qgscoordinatetransform.cpp.

◆ datumTransformString()

QString QgsCoordinateTransform::datumTransformString ( int datumTransform )

static

Definition at line 917 of file qgscoordinatetransform.cpp.

◆ destCRS()

const QgsCoordinateReferenceSystem& QgsCoordinateTransform::destCRS ( ) const

inline

Get the QgsCoordinateReferenceSystem representation of the map canvas coordinate system

Returns: QgsCoordinateReferenceSystem of the map canvas coordinate system

Definition at line 125 of file qgscoordinatetransform.h.

◆ destinationDatumTransform()

int QgsCoordinateTransform::destinationDatumTransform ( ) const

inline

Definition at line 233 of file qgscoordinatetransform.h.

◆ initialise

void QgsCoordinateTransform::initialise ( )

slot

initialize is used to actually create the Transformer instance

Definition at line 145 of file qgscoordinatetransform.cpp.

◆ invalidTransformInput

void QgsCoordinateTransform::invalidTransformInput ( ) const

signal

Signal when an invalid pj_transform() has occurred.

◆ isInitialised()

bool QgsCoordinateTransform::isInitialised ( ) const

inline

Flag to indicate whether the coordinate systems have been initialized

Returns: true if initialized, otherwise false

Definition at line 204 of file qgscoordinatetransform.h.

◆ isShortCircuited()

bool QgsCoordinateTransform::isShortCircuited ( ) const

inline

See if the transform short circuits because src and dest are equivalent.

Returns: bool True if it short circuits

Definition at line 209 of file qgscoordinatetransform.h.

◆ readXML

bool QgsCoordinateTransform::readXML ( QDomNode & theNode )

slot

Restores state from the given Dom node.

Parameters

theNode The node from which state will be restored

Returns: bool True on success, False on failure

Definition at line 733 of file qgscoordinatetransform.cpp.

◆ setDestCRS()

void QgsCoordinateTransform::setDestCRS ( const QgsCoordinateReferenceSystem & theCRS )

Mutator for dest QgsCoordinateReferenceSystem

Parameters

theCRS of the destination coordinate system

Definition at line 130 of file qgscoordinatetransform.cpp.

◆ setDestCRSID()

void QgsCoordinateTransform::setDestCRSID ( long theCRSID )

Change the destination coordinate system by passing it a qgis srsid A QGIS srsid is a unique key value to an entry on the tbl_srs in the srs.db sqlite database.

Note: This slot will usually be called if the project properties change and a different coordinate system is selected.; This coord transform will be reinitialized when this slot is called to check if short circuiting is needed or not etc.

Parameters

theCRSID - A long representing the srsid of the srs to be used

todo Add some logic here to determine if the srsid is a system or user one

Definition at line 136 of file qgscoordinatetransform.cpp.

◆ setDestinationDatumTransform()

void QgsCoordinateTransform::setDestinationDatumTransform ( int dt )

inline

Definition at line 234 of file qgscoordinatetransform.h.

◆ setSourceCrs()

void QgsCoordinateTransform::setSourceCrs ( const QgsCoordinateReferenceSystem & theCRS )

Set the source (layer) QgsCoordinateReferenceSystem

Parameters

theCRS QgsCoordinateReferenceSystem representation of the layer's coordinate system

Definition at line 125 of file qgscoordinatetransform.cpp.

◆ setSourceDatumTransform()

void QgsCoordinateTransform::setSourceDatumTransform ( int dt )

inline

Definition at line 232 of file qgscoordinatetransform.h.

◆ sourceCrs()

const QgsCoordinateReferenceSystem& QgsCoordinateTransform::sourceCrs ( ) const

inline

Get the QgsCoordinateReferenceSystem representation of the layer's coordinate system

Returns: QgsCoordinateReferenceSystem of the layer's coordinate system

Definition at line 119 of file qgscoordinatetransform.h.

◆ sourceDatumTransform()

int QgsCoordinateTransform::sourceDatumTransform ( ) const

inline

Definition at line 231 of file qgscoordinatetransform.h.

◆ transform() [1/3]

QgsPoint QgsCoordinateTransform::transform	(	const QgsPoint &	p,
		TransformDirection	direction = `ForwardTransform`
	)		const

Transform the point from Source Coordinate System to Destination Coordinate System If the direction is ForwardTransform then coordinates are transformed from layer CS –> map canvas CS, otherwise points are transformed from map canvas CS to layerCS.

Parameters

p	Point to transform
direction	TransformDirection (defaults to ForwardTransform)

Returns: QgsPoint in Destination Coordinate System

Definition at line 260 of file qgscoordinatetransform.cpp.

◆ transform() [2/3]

QgsPoint QgsCoordinateTransform::transform	(	const double	x,
		const double	y = `0.0`,
		TransformDirection	direction = `ForwardTransform`
	)		const

Transform the point specified by x,y from Source Coordinate System to Destination Coordinate System If the direction is ForwardTransform then coordinates are transformed from layer CS –> map canvas CS, otherwise points are transformed from map canvas CS to layerCS.

Parameters

x	x cordinate of point to transform
y	y coordinate of point to transform
direction	TransformDirection (defaults to ForwardTransform)

Returns: QgsPoint in Destination Coordinate System

Definition at line 283 of file qgscoordinatetransform.cpp.

◆ transform() [3/3]

QgsRectangle QgsCoordinateTransform::transform	(	const QgsRectangle &	theRect,
		TransformDirection	direction = `ForwardTransform`
	)		const

Transform a QgsRectangle to the dest Coordinate system If the direction is ForwardTransform then coordinates are transformed from layer CS –> map canvas CS, otherwise points are transformed from map canvas CS to layerCS.

Parameters

theRect	rect to transform
direction	TransformDirection (defaults to ForwardTransform)

Returns: QgsRectangle in Destination Coordinate System

Definition at line 297 of file qgscoordinatetransform.cpp.

◆ transformBoundingBox()

QgsRectangle QgsCoordinateTransform::transformBoundingBox	(	const QgsRectangle &	theRect,
		TransformDirection	direction = `ForwardTransform`,
		const bool	handle180Crossover = `false`
	)		const

Transform a QgsRectangle to the dest Coordinate system If the direction is ForwardTransform then coordinates are transformed from layer CS –> map canvas CS, otherwise points are transformed from map canvas CS to layerCS.

It assumes that rect is a bounding box, and creates a bounding box in the proejcted CS, so that all points in source rectangle is within returned rectangle.

Parameters

theRect	rect to transform
direction	TransformDirection (defaults to ForwardTransform)
handle180Crossover	set to true if destination crs is geographic and handling of extents crossing the 180 degree longitude line is required

Returns: QgsRectangle in Destination Coordinate System

Definition at line 503 of file qgscoordinatetransform.cpp.

◆ transformCoords()

void QgsCoordinateTransform::transformCoords	(	int	numPoint,
		double *	x,
		double *	y,
		double *	z,
		TransformDirection	direction = `ForwardTransform`
	)		const

Transform an array of coordinates to a different Coordinate System If the direction is ForwardTransform then coordinates are transformed from layer CS –> map canvas CS, otherwise points are transformed from map canvas CS to layerCS.

Parameters

numPoint	number of coordinates in arrays
x	array of x coordinates to transform
y	array of y coordinates to transform
z	array of z coordinates to transform
direction	TransformDirection (defaults to ForwardTransform)

Returns: QgsRectangle in Destination Coordinate System

Definition at line 617 of file qgscoordinatetransform.cpp.

◆ transformInPlace() [1/5]

void QgsCoordinateTransform::transformInPlace	(	double &	x,
		double &	y,
		double &	z,
		TransformDirection	direction = `ForwardTransform`
	)		const

Definition at line 333 of file qgscoordinatetransform.cpp.

◆ transformInPlace() [2/5]

void QgsCoordinateTransform::transformInPlace	(	float &	x,
		float &	y,
		double &	z,
		TransformDirection	direction = `ForwardTransform`
	)		const

Note: not available in python bindings

Definition at line 354 of file qgscoordinatetransform.cpp.

◆ transformInPlace() [3/5]

void QgsCoordinateTransform::transformInPlace	(	float &	x,
		float &	y,
		float &	z,
		TransformDirection	direction = `ForwardTransform`
	)		const

Note: not available in python bindings

Definition at line 363 of file qgscoordinatetransform.cpp.

◆ transformInPlace() [4/5]

void QgsCoordinateTransform::transformInPlace	(	QVector< float > &	x,
		QVector< float > &	y,
		QVector< float > &	z,
		TransformDirection	direction = `ForwardTransform`
	)		const

Note: not available in python bindings

Definition at line 458 of file qgscoordinatetransform.cpp.

◆ transformInPlace() [5/5]

void QgsCoordinateTransform::transformInPlace	(	QVector< double > &	x,
		QVector< double > &	y,
		QVector< double > &	z,
		TransformDirection	direction = `ForwardTransform`
	)		const

Note: not available in python bindings

Definition at line 431 of file qgscoordinatetransform.cpp.

◆ transformPolygon()

void QgsCoordinateTransform::transformPolygon	(	QPolygonF &	poly,
		TransformDirection	direction = `ForwardTransform`
	)		const

Definition at line 390 of file qgscoordinatetransform.cpp.

◆ writeXML

bool QgsCoordinateTransform::writeXML	(	QDomNode &	theNode,
		QDomDocument &	theDoc
	)

slot

Stores state to the given Dom node in the given document.

Parameters

theNode	The node in which state will be restored
theDoc	The document in which state will be stored

Returns: bool True on success, False on failure

Definition at line 752 of file qgscoordinatetransform.cpp.

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

/tmp/buildd/qgis-2.18.21+99unstable/src/core/qgscoordinatetransform.h
/tmp/buildd/qgis-2.18.21+99unstable/src/core/qgscoordinatetransform.cpp

Public Types

Public Slots

Signals

Public Member Functions

Static Public Member Functions

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ TransformDirection

Constructor & Destructor Documentation

◆ QgsCoordinateTransform() [1/5]

◆ QgsCoordinateTransform() [2/5]

◆ QgsCoordinateTransform() [3/5]

◆ QgsCoordinateTransform() [4/5]

◆ QgsCoordinateTransform() [5/5]

◆ ~QgsCoordinateTransform()

Member Function Documentation

◆ clone()

◆ datumTransformations()

◆ datumTransformCrsInfo()

◆ datumTransformString()

◆ destCRS()

◆ destinationDatumTransform()

◆ initialise

◆ invalidTransformInput

◆ isInitialised()

◆ isShortCircuited()

◆ readXML

◆ setDestCRS()

◆ setDestCRSID()

◆ setDestinationDatumTransform()

◆ setSourceCrs()

◆ setSourceDatumTransform()

◆ sourceCrs()

◆ sourceDatumTransform()

◆ transform() [1/3]

◆ transform() [2/3]

◆ transform() [3/3]

◆ transformBoundingBox()

◆ transformCoords()

◆ transformInPlace() [1/5]

◆ transformInPlace() [2/5]

◆ transformInPlace() [3/5]

◆ transformInPlace() [4/5]

◆ transformInPlace() [5/5]

◆ transformPolygon()

◆ writeXML