QGIS/python/core/qgscoordinatetransformcontext.sip

/************************************************************************
 * This file has been generated automatically from                      *
 *                                                                      *
 * src/core/qgscoordinatetransformcontext.h                             *
 *                                                                      *
 * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
 ************************************************************************/








class QgsCoordinateTransformContext
{
%Docstring
 Contains information about the context in which a coordinate transform is executed.

 The context stores various information regarding which coordinate transforms should
 be used when transforming points from a source to destination coordinate reference
 system.

 The highest priority transforms are those set using addSourceDestinationDatumTransform()
 and which the transform has a matching source to destination CRS pair.

 Failing this, if the source CRS has a matching transform specified by
 addSourceDatumTransform() then this datum transform will be used. The same logic
 applies for destination CRS transforms set using addDestinationDatumTransform().

.. note::

   QgsCoordinateTransformContext objects are thread safe for read and write.

.. note::

   QgsCoordinateTransformContext objects are implicitly shared.

.. versionadded:: 3.0
%End

%TypeHeaderCode
#include "qgscoordinatetransformcontext.h"
%End
  public:

    QgsCoordinateTransformContext();
%Docstring
 Constructor for QgsCoordinateTransformContext.
%End

    QgsCoordinateTransformContext( const QgsCoordinateTransformContext &rhs );
%Docstring
 Copy constructor
%End



    void clear();
%Docstring
 Clears all stored transform information from the context.
%End



    QMap< QPair< QString, QString>, QgsCoordinateTransform::TransformPair > sourceDestinationDatumTransforms() const;
%Docstring
 Returns the stored mapping for source to destination CRS pairs to associated datum transforms to use.
 The map keys will be QgsCoordinateReferenceSystems.authid()s.

 If either the source transform ID or destination transform ID is -1, then no datum transform is
 required for transformations for that source or destination.

 \warning This method should not be used to calculate the corresponding datum transforms
 to use for a coordinate transform. Instead, always use calculateDatumTransforms()
 to determine this.

.. seealso:: addSourceDestinationDatumTransform()
 :rtype: QMap< QPair< str, QString>, QgsCoordinateTransform.TransformPair >
%End

    bool addSourceDestinationDatumTransform( const QgsCoordinateReferenceSystem &sourceCrs,
        const QgsCoordinateReferenceSystem &destinationCrs,
        int sourceTransformId,
        int destinationTransformId );
%Docstring
 Adds a new ``sourceTransform`` and ``destinationTransform`` to use when projecting coordinates
 from the the specified ``sourceCrs`` to the specified ``destinationCrs``.

 If either ``sourceTransformId`` or ``destinationTransformId`` is -1, then no datum transform is
 required for transformations for that source or destination.

 Returns true if the new transform pair was added successfully.

.. note::

   Transforms set using this method will override any specific source or destination
 transforms set by addSourceDatumTransform() or addDestinationDatumTransform().

.. seealso:: sourceDestinationDatumTransforms()
.. seealso:: removeSourceDestinationDatumTransform()
 :rtype: bool
%End

    void removeSourceDestinationDatumTransform( const QgsCoordinateReferenceSystem &sourceCrs,
        const QgsCoordinateReferenceSystem &destinationCrs );
%Docstring
 Removes the source to destination datum transform pair for the specified ``sourceCrs`` and
 ``destinationCrs``.
.. seealso:: addSourceDestinationDatumTransform()
%End

    bool hasTransform( const QgsCoordinateReferenceSystem &source,
                       const QgsCoordinateReferenceSystem &destination ) const;
%Docstring
 Returns true if the context has a valid datum transform to use
 when transforming from the specified ``source`` CRS to ``destination`` CRS.
.. note::

   source and destination are reversible.
 :rtype: bool
%End

    QgsCoordinateTransform::TransformPair calculateDatumTransforms( const QgsCoordinateReferenceSystem &source,
        const QgsCoordinateReferenceSystem &destination ) const;
%Docstring
 Returns the pair of source and destination datum transforms to use
 for a transform from the specified ``source`` CRS to ``destination`` CRS.

 Returns an ID of -1 if a datum transform should not be used for the source or
 destination.

.. note::

   source and destination are reversible.
 :rtype: QgsCoordinateTransform.TransformPair
%End

    void readXml( const QDomElement &element, const QDomDocument &document, const QgsReadWriteContext &context );
%Docstring
 Reads the context's state from a DOM ``element``.
.. seealso:: writeXml()
%End

    void writeXml( QDomElement &element, QDomDocument &document, const QgsReadWriteContext &context ) const;
%Docstring
 Writes the context's state to a DOM ``element``.
.. seealso:: readXml()
%End


    void readSettings();
%Docstring
 Reads the context's state from application settings.
.. seealso:: readSettings()
%End

    void writeSettings();
%Docstring
 Write the context's state to application settings.
.. seealso:: writeSettings()
%End


};





/************************************************************************
 * This file has been generated automatically from                      *
 *                                                                      *
 * src/core/qgscoordinatetransformcontext.h                             *
 *                                                                      *
 * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
 ************************************************************************/