QgsGcpGeometryTransformer Class Reference

A geometry transformer which uses an underlying Ground Control Points (GCP) based transformation to modify geometries. More...

#include <qgsgcpgeometrytransformer.h>

Inheritance diagram for QgsGcpGeometryTransformer:

Public Member Functions
	QgsGcpGeometryTransformer (const QgsGcpGeometryTransformer &other)=delete
	QgsGcpGeometryTransformer (QgsGcpTransformerInterface *gcpTransformer)
	Constructor for QgsGcpGeometryTransformer, which uses the specified gcpTransformer to modify geometries.
	QgsGcpGeometryTransformer (QgsGcpTransformerInterface::TransformMethod method, const QVector< QgsPointXY > &sourceCoordinates, const QVector< QgsPointXY > &destinationCoordinates)
	Constructor for QgsGcpGeometryTransformer, which uses the specified transform method and list of source and destination coordinates to transform geometries.
	~QgsGcpGeometryTransformer () override
QgsGcpTransformerInterface *	gcpTransformer () const
	Returns the underlying GCP transformer used to transform geometries.
QgsGcpGeometryTransformer &	operator= (const QgsGcpGeometryTransformer &other)=delete
void	setGcpTransformer (QgsGcpTransformerInterface *transformer)
	Sets the underlying GCP transformer used to transform geometries.
QgsGeometry	transform (const QgsGeometry &geometry, bool &ok, QgsFeedback *feedback=nullptr)
	Transforms the specified input geometry using the GCP based transform.
bool	transformPoint (double &x, double &y, double &z, double &m) override
	Transforms the point defined by the coordinates (x, y, z) and the specified m value.
Public Member Functions inherited from QgsAbstractGeometryTransformer
virtual	~QgsAbstractGeometryTransformer ()=default

Detailed Description

A geometry transformer which uses an underlying Ground Control Points (GCP) based transformation to modify geometries.

Since

QGIS 3.18

Definition at line 36 of file qgsgcpgeometrytransformer.h.

Constructor & Destructor Documentation

QgsGcpGeometryTransformer() [1/3]

QgsGcpGeometryTransformer::QgsGcpGeometryTransformer

(

QgsGcpTransformerInterface *

gcpTransformer

)

Constructor for QgsGcpGeometryTransformer, which uses the specified gcpTransformer to modify geometries.

Ownership of gcpTransformer is transferred to the geometry transformer.

Definition at line 21 of file qgsgcpgeometrytransformer.cpp.

QgsGcpGeometryTransformer() [2/3]

QgsGcpGeometryTransformer::QgsGcpGeometryTransformer	(	QgsGcpTransformerInterface::TransformMethod	method,
		const QVector< QgsPointXY > &	sourceCoordinates,
		const QVector< QgsPointXY > &	destinationCoordinates
	)

Constructor for QgsGcpGeometryTransformer, which uses the specified transform method and list of source and destination coordinates to transform geometries.

Definition at line 27 of file qgsgcpgeometrytransformer.cpp.

~QgsGcpGeometryTransformer()

QgsGcpGeometryTransformer::~QgsGcpGeometryTransformer ( )

overridedefault

QgsGcpGeometryTransformer() [3/3]

QgsGcpGeometryTransformer::QgsGcpGeometryTransformer ( const QgsGcpGeometryTransformer &  other )

delete

Member Function Documentation

gcpTransformer()

QgsGcpTransformerInterface * QgsGcpGeometryTransformer::gcpTransformer

(

)

const

Returns the underlying GCP transformer used to transform geometries.

See also

setGcpTransformer()

Definition at line 59 of file qgsgcpgeometrytransformer.cpp.

operator=()

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

delete

setGcpTransformer()

void QgsGcpGeometryTransformer::setGcpTransformer

(

QgsGcpTransformerInterface *

transformer

)

Sets the underlying GCP transformer used to transform geometries.

Ownership is transferred to this object.

See also

gcpTransformer()

Definition at line 64 of file qgsgcpgeometrytransformer.cpp.

transform()

QgsGeometry QgsGcpGeometryTransformer::transform	(	const QgsGeometry &	geometry,
		bool &	ok,
		QgsFeedback *	feedback = nullptr
	)

Transforms the specified input geometry using the GCP based transform.

Parameters

geometry	Input geometry to transform
ok	will be set to true if geometry was successfully transformed, or false if an error occurred
feedback	This optional argument can be used to cancel the transformation before it completes. If this is done, the geometry will be left in a semi-transformed state.

Returns

transformed geometry

Definition at line 43 of file qgsgcpgeometrytransformer.cpp.

transformPoint()

bool QgsGcpGeometryTransformer::transformPoint ( double &  x, double &  y, double &  z, double &  m  )

overridevirtual

Transforms the point defined by the coordinates (x, y, z) and the specified m value.

Parameters

x	point x coordinate
y	point y coordinate
z	point z coordinate, or NaN if the input point is 2D only
m	point m value, or NaN if not available

Returns

true if point was transformed (or no transformation was required), or false if point could not be transformed successfully.

Example

A transformer which multiples the x coordinate by 3 and adds 10 to the y coordinate:

class MyTransformer(QgsAbstractGeometryTransformer):
 
  def transformPoint(self, x, y, z, m):
    # returns a tuple of True to indicate success, then the modified x/y/z/m values
    return True, x*3, y+10, z, m

Implements QgsAbstractGeometryTransformer.

Definition at line 35 of file qgsgcpgeometrytransformer.cpp.

---

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

• /build/qgis-3.41.0+git20241110+fda2aa46e9a+99sid/src/analysis/georeferencing/qgsgcpgeometrytransformer.h
• /build/qgis-3.41.0+git20241110+fda2aa46e9a+99sid/src/analysis/georeferencing/qgsgcpgeometrytransformer.cpp