QGIS/python/core/qgscoordinatetransform.sip

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/** \ingroup core
* 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.
*
* When used to transform between a layer and the map canvas, 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 layer's coordinate system to the map canvas.
* \note Since QGIS 3.0 QgsCoordinateReferenceSystem objects are implicitly shared.
*/
class QgsCoordinateTransform
{
%TypeHeaderCode
#include <qgscoordinatetransform.h>
%End
public:
//! Enum used to indicate the direction (forward or inverse) of the transform
enum TransformDirection
{
ForwardTransform, /*!< Transform from source to destination CRS. */
ReverseTransform /*!< Transform from destination to source CRS. */
};
/** Default constructor, creates an invalid QgsCoordinateTransform. */
QgsCoordinateTransform();
/** Constructs a QgsCoordinateTransform using QgsCoordinateReferenceSystem objects.
* @param source source CRS, typically of the layer's coordinate system
* @param destination CRS, typically of the map canvas coordinate system
*/
QgsCoordinateTransform( const QgsCoordinateReferenceSystem& source,
const QgsCoordinateReferenceSystem& destination );
/*!
* Returns true if the coordinate transform is valid, ie both the source and destination
* CRS have been set and are valid.
* @note added in QGIS 3.0
*/
bool isValid() const;
/*!
* Sets the source coordinate reference system.
* @param crs CRS to transform coordinates from
* @see sourceCrs()
* @see setDestinationCrs()
*/
void setSourceCrs( const QgsCoordinateReferenceSystem& crs );
/*!
* Sets the destination coordinate reference system.
* @param crs CRS to transform coordinates to
* @see destinationCrs()
* @see setSourceCrs()
*/
void setDestinationCrs( const QgsCoordinateReferenceSystem& crs );
/** Returns the source coordinate reference system, which the transform will
* transform coordinates from.
* @see setSourceCrs()
* @see destinationCrs()
*/
QgsCoordinateReferenceSystem sourceCrs() const;
/** Returns the destination coordinate reference system, which the transform will
* transform coordinates to.
* @see setDestinationCrs()
* @see sourceCrs()
*/
QgsCoordinateReferenceSystem destinationCrs() const;
/** Transform the point from the source CRS to the destination CRS.
* If the direction is ForwardTransform then coordinates are transformed from source to destination,
* otherwise points are transformed from destination to source CRS.
* @param point point to transform
* @param direction transform direction (defaults to ForwardTransform)
* @return transformed point
*/
QgsPoint transform( const QgsPoint& point, TransformDirection direction = ForwardTransform ) const;
/** Transform the point specified by x,y from the source CRS to the destination CRS.
* If the direction is ForwardTransform then coordinates are transformed from source to destination,
* otherwise points are transformed from destination to source CRS.
* @param x x coordinate of point to transform
* @param y y coordinate of point to transform
* @param direction transform direction (defaults to ForwardTransform)
* @return transformed point
*/
QgsPoint transform( const double x, const double y, TransformDirection direction = ForwardTransform ) const;
/** Transforms a rectangle from the source CRS to the destination CRS.
* If the direction is ForwardTransform then coordinates are transformed from source to destination,
* otherwise points are transformed from destination to source CRS.
* This method assumes that the rectangle is a bounding box, and creates a bounding box
* in the projected CRS, such that all points from the source rectangle are within
* the returned rectangle.
* @param rectangle rectangle to transform
* @param direction transform direction (defaults to ForwardTransform)
* @param handle180Crossover set to true if destination CRS is geographic and handling of extents
* crossing the 180 degree longitude line is required
* @return rectangle in destination CRS
*/
QgsRectangle transformBoundingBox( const QgsRectangle& rectangle, TransformDirection direction = ForwardTransform, const bool handle180Crossover = false ) const;
/** Transforms an array of x, y and z double coordinates in place, from the source CRS to the destination CRS.
* If the direction is ForwardTransform then coordinates are transformed from source to destination,
* otherwise points are transformed from destination to source CRS.
* @param x array of x coordinates of points to transform
* @param y array of y coordinates of points to transform
* @param z array of z coordinates of points to transform. The z coordinates of the points
* must represent height relative to the vertical datum of the source CRS (generally ellipsoidal
* heights) and must be expressed in its vertical units (generally meters)
* @param direction transform direction (defaults to ForwardTransform)
*/
void transformInPlace( double& x, double& y, double &z, TransformDirection direction = ForwardTransform ) const;
/** Transforms an array of x, y and z float coordinates in place, from the source CRS to the destination CRS.
* If the direction is ForwardTransform then coordinates are transformed from source to destination,
* otherwise points are transformed from destination to source CRS.
* @param x array of x coordinates of points to transform
* @param y array of y coordinates of points to transform
* @param z array of z coordinates of points to transform. The z coordinates of the points
* must represent height relative to the vertical datum of the source CRS (generally ellipsoidal
* heights) and must be expressed in its vertical units (generally meters)
* @param direction transform direction (defaults to ForwardTransform)
* @note not available in python bindings
*/
//void transformInPlace( float& x, float& y, double &z, TransformDirection direction = ForwardTransform ) const;
/** Transforms an array of x, y and z float coordinates in place, from the source CRS to the destination CRS.
* If the direction is ForwardTransform then coordinates are transformed from source to destination,
* otherwise points are transformed from destination to source CRS.
* @param x array of x coordinates of points to transform
* @param y array of y coordinates of points to transform
* @param z array of z coordinates of points to transform. The z coordinates of the points
* must represent height relative to the vertical datum of the source CRS (generally ellipsoidal
* heights) and must be expressed in its vertical units (generally meters)
* @param direction transform direction (defaults to ForwardTransform)
* @note not available in python bindings
*/
// void transformInPlace( float& x, float& y, float& z, TransformDirection direction = ForwardTransform ) const;
/** Transforms a vector of x, y and z float coordinates in place, from the source CRS to the destination CRS.
* If the direction is ForwardTransform then coordinates are transformed from source to destination,
* otherwise points are transformed from destination to source CRS.
* @param x vector of x coordinates of points to transform
* @param y vector of y coordinates of points to transform
* @param z vector of z coordinates of points to transform. The z coordinates of the points
* must represent height relative to the vertical datum of the source CRS (generally ellipsoidal
* heights) and must be expressed in its vertical units (generally meters)
* @param direction transform direction (defaults to ForwardTransform)
* @note not available in python bindings
*/
//void transformInPlace( QVector<float>& x, QVector<float>& y, QVector<float>& z,
// TransformDirection direction = ForwardTransform ) const;
/** Transforms a vector of x, y and z double coordinates in place, from the source CRS to the destination CRS.
* If the direction is ForwardTransform then coordinates are transformed from source to destination,
* otherwise points are transformed from destination to source CRS.
* @param x vector of x coordinates of points to transform
* @param y vector of y coordinates of points to transform
* @param z vector of z coordinates of points to transform. The z coordinates of the points
* must represent height relative to the vertical datum of the source CRS (generally ellipsoidal
* heights) and must be expressed in its vertical units (generally meters)
* @param direction transform direction (defaults to ForwardTransform)
* @note not available in python bindings
*/
//void transformInPlace( QVector<double>& x, QVector<double>& y, QVector<double>& z,
// TransformDirection direction = ForwardTransform ) const;
/** Transforms a polygon to the destination coordinate system.
* @param polygon polygon to transform (occurs in place)
* @param direction transform direction (defaults to forward transformation)
*/
void transformPolygon( QPolygonF& polygon, TransformDirection direction = ForwardTransform ) const;
/** Transforms a rectangle to the destination CRS.
* If the direction is ForwardTransform then coordinates are transformed from source to destination,
* otherwise points are transformed from destination to source CRS.
* @param rectangle rectangle to transform
* @param direction transform direction (defaults to ForwardTransform)
* @return transformed rectangle
*/
QgsRectangle transform( const QgsRectangle &rectangle, TransformDirection direction = ForwardTransform ) const;
/** Transform an array of coordinates to the destination CRS.
* If the direction is ForwardTransform then coordinates are transformed from source to destination,
* otherwise points are transformed from destination to source CRS.
* @param numPoint number of coordinates in arrays
* @param x array of x coordinates to transform
* @param y array of y coordinates to transform
* @param z array of z coordinates to transform
* @param direction transform direction (defaults to ForwardTransform)
*/
void transformCoords( int numPoint, double *x, double *y, double *z, TransformDirection direction = ForwardTransform ) const;
/** Returns true if the transform short circuits because the source and destination are equivalent.
*/
bool isShortCircuited() const;
/** Returns list of datum transformations for the given src and dest CRS
* @note not available in python bindings
*/
// static QList< QList< int > > datumTransformations( const QgsCoordinateReferenceSystem& srcCRS, const QgsCoordinateReferenceSystem& destCRS );
static QString datumTransformString( int datumTransform );
/** Gets name of source and dest geographical CRS (to show in a tooltip)
@return epsgNr epsg code of the transformation (or 0 if not in epsg db)*/
static bool datumTransformCrsInfo( int datumTransform, int& epsgNr, QString& srcProjection, QString& dstProjection, QString &remarks, QString &scope, bool &preferred, bool &deprecated );
int sourceDatumTransform() const;
void setSourceDatumTransform( int dt );
int destinationDatumTransform() const;
void setDestinationDatumTransform( int dt );
//!initialize is used to actually create the Transformer instance
void initialize();
/** Restores state from the given Dom node.
* @param node The node from which state will be restored
* @return bool True on success, False on failure
* @see writeXml()
*/
bool readXml( const QDomNode& node );
/** Stores state to the given Dom node in the given document
* @param node The node in which state will be restored
* @param document The document in which state will be stored
* @return bool True on success, False on failure
* @see readXml()
*/
bool writeXml( QDomNode & node, QDomDocument & document ) const;
};