This class has all the configuration of snapping and can return answers to snapping queries. More...

#include <qgssnappingutils.h>

Inheritance diagram for QgsSnappingUtils:

Classes
struct	LayerConfig
	Configures how a certain layer should be handled in a snapping operation. More...

Public Types
enum	IndexingStrategy { IndexAlwaysFull, IndexNeverFull, IndexHybrid, IndexExtent }

Public Slots
void	setConfig (const QgsSnappingConfig &snappingConfig)
	The snapping configuration controls the behavior of this object. More...

void	toggleEnabled ()
	Toggles the state of snapping. More...

Signals
void	configChanged (const QgsSnappingConfig &snappingConfig)
	Emitted when the snapping settings object changes. More...

Public Member Functions
	QgsSnappingUtils (QObject *parent=nullptr, bool enableSnappingForInvisibleFeature=true)
	Constructor for QgsSnappingUtils. More...

	~QgsSnappingUtils () override

QgsSnappingConfig	config () const
	The snapping configuration controls the behavior of this object. More...

QgsVectorLayer *	currentLayer () const
	The current layer used if mode is SnapCurrentLayer. More...

QString	dump ()
	Gets extra information about the instance. More...

IndexingStrategy	indexingStrategy () const
	Find out which strategy is used for indexing - by default hybrid indexing is used. More...

QList< QgsSnappingUtils::LayerConfig >	layers () const
	Query layers used for snapping. More...

QgsPointLocator *	locatorForLayer (QgsVectorLayer *vl)
	Gets a point locator for the given layer. If such locator does not exist, it will be created. More...

QgsMapSettings	mapSettings () const

void	setCurrentLayer (QgsVectorLayer *layer)
	Sets current layer so that if mode is SnapCurrentLayer we know which layer to use. More...

void	setEnableSnappingForInvisibleFeature (bool enable)
	Set if invisible features must be snapped or not. More...

void	setIndexingStrategy (IndexingStrategy strategy)
	Sets a strategy for indexing geometry data - determines how fast and memory consuming the data structures will be. More...

void	setMapSettings (const QgsMapSettings &settings)
	Assign current map settings to the utils - used for conversion between screen coords to map coords. More...

QgsPointLocator::Match	snapToCurrentLayer (QPoint point, QgsPointLocator::Types type, QgsPointLocator::MatchFilter *filter=nullptr)
	Snap to current layer. More...

QgsPointLocator::Match	snapToMap (QPoint point, QgsPointLocator::MatchFilter *filter=nullptr)
	Snap to map according to the current configuration. Optional filter allows discarding unwanted matches. More...

QgsPointLocator::Match	snapToMap (const QgsPointXY &pointMap, QgsPointLocator::MatchFilter *filter=nullptr)

Protected Member Functions
void	clearAllLocators ()
	Deletes all existing locators (e.g. when destination CRS has changed and we need to reindex) More...

virtual void	prepareIndexProgress (int index)
	Called when finished indexing a layer. When index == count the indexing is complete. More...

virtual void	prepareIndexStarting (int count)
	Called when starting to index - can be overridden and e.g. progress dialog can be provided. More...

Properties
QgsSnappingConfig	config

Detailed Description

This class has all the configuration of snapping and can return answers to snapping queries.

Internally, it keeps a cache of QgsPointLocator instances for multiple layers.

Currently it supports the following queries:

snapToMap() - has multiple modes of operation
snapToCurrentLayer() For more complex queries it is possible to use locatorForLayer() method that returns point locator instance with layer's indexed data.

Indexing strategy determines how fast the queries will be and how much memory will be used.

When working with map canvas, it may be useful to use derived class QgsMapCanvasSnappingUtils which keeps the configuration in sync with map canvas (e.g. current view, active layer).

Since: QGIS 2.8

Definition at line 47 of file qgssnappingutils.h.

Member Enumeration Documentation

enum QgsSnappingUtils::IndexingStrategy

Enumerator
IndexAlwaysFull	For all layers build index of full extent. Uses more memory, but queries are faster.
IndexNeverFull	For all layers only create temporary indexes of small extent. Low memory usage, slower queries.
IndexHybrid	For "big" layers using IndexNeverFull, for the rest IndexAlwaysFull. Compromise between speed and memory usage.
IndexExtent	For all layer build index of extent given in map settings.

Definition at line 86 of file qgssnappingutils.h.

Constructor & Destructor Documentation

QgsSnappingUtils::QgsSnappingUtils	(	QObject *	parent = `nullptr`,
		bool	enableSnappingForInvisibleFeature = `true`
	)

Constructor for QgsSnappingUtils.

Definition at line 24 of file qgssnappingutils.cpp.

QgsSnappingUtils::~QgsSnappingUtils ( )

override

Definition at line 31 of file qgssnappingutils.cpp.

Member Function Documentation

void QgsSnappingUtils::clearAllLocators ( )

protected

Deletes all existing locators (e.g. when destination CRS has changed and we need to reindex)

Definition at line 50 of file qgssnappingutils.cpp.

QgsSnappingConfig QgsSnappingUtils::config ( ) const

The snapping configuration controls the behavior of this object.

void QgsSnappingUtils::configChanged ( const QgsSnappingConfig & snappingConfig )

signal

Emitted when the snapping settings object changes.

QgsVectorLayer* QgsSnappingUtils::currentLayer ( ) const

inline

The current layer used if mode is SnapCurrentLayer.

Definition at line 82 of file qgssnappingutils.h.

QString QgsSnappingUtils::dump ( )

Gets extra information about the instance.

Since: QGIS 2.14

Definition at line 498 of file qgssnappingutils.cpp.

IndexingStrategy QgsSnappingUtils::indexingStrategy ( ) const

inline

Find out which strategy is used for indexing - by default hybrid indexing is used.

Definition at line 97 of file qgssnappingutils.h.

QList<QgsSnappingUtils::LayerConfig> QgsSnappingUtils::layers ( ) const

inline

Query layers used for snapping.

Definition at line 149 of file qgssnappingutils.h.

QgsPointLocator * QgsSnappingUtils::locatorForLayer ( QgsVectorLayer * vl )

Gets a point locator for the given layer. If such locator does not exist, it will be created.

Definition at line 37 of file qgssnappingutils.cpp.

QgsMapSettings QgsSnappingUtils::mapSettings ( ) const

inline

Definition at line 77 of file qgssnappingutils.h.

virtual void QgsSnappingUtils::prepareIndexProgress ( int index )

inlineprotectedvirtual

Called when finished indexing a layer. When index == count the indexing is complete.

Reimplemented in QgsMapCanvasSnappingUtils.

Definition at line 196 of file qgssnappingutils.h.

virtual void QgsSnappingUtils::prepareIndexStarting ( int count )

inlineprotectedvirtual

Called when starting to index - can be overridden and e.g. progress dialog can be provided.

Reimplemented in QgsMapCanvasSnappingUtils.

Definition at line 194 of file qgssnappingutils.h.

void QgsSnappingUtils::setConfig ( const QgsSnappingConfig & snappingConfig )

slot

The snapping configuration controls the behavior of this object.

Definition at line 447 of file qgssnappingutils.cpp.

void QgsSnappingUtils::setCurrentLayer ( QgsVectorLayer * layer )

Sets current layer so that if mode is SnapCurrentLayer we know which layer to use.

Definition at line 493 of file qgssnappingutils.cpp.

void QgsSnappingUtils::setEnableSnappingForInvisibleFeature ( bool enable )

Set if invisible features must be snapped or not.

Parameters

enable Enable or not this feature

Since: QGIS 3.2

Definition at line 442 of file qgssnappingutils.cpp.

void QgsSnappingUtils::setIndexingStrategy ( IndexingStrategy strategy )

inline

Sets a strategy for indexing geometry data - determines how fast and memory consuming the data structures will be.

Definition at line 95 of file qgssnappingutils.h.

void QgsSnappingUtils::setMapSettings ( const QgsMapSettings & settings )

Assign current map settings to the utils - used for conversion between screen coords to map coords.

Definition at line 483 of file qgssnappingutils.cpp.

QgsPointLocator::Match QgsSnappingUtils::snapToCurrentLayer	(	QPoint	point,
		QgsPointLocator::Types	type,
		QgsPointLocator::MatchFilter *	filter = `nullptr`
	)

Snap to current layer.

Snap to current layer

Definition at line 466 of file qgssnappingutils.cpp.

QgsPointLocator::Match QgsSnappingUtils::snapToMap	(	QPoint	point,
		QgsPointLocator::MatchFilter *	filter = `nullptr`
	)

Snap to map according to the current configuration. Optional filter allows discarding unwanted matches.

Definition at line 218 of file qgssnappingutils.cpp.

QgsPointLocator::Match QgsSnappingUtils::snapToMap	(	const QgsPointXY &	pointMap,
		QgsPointLocator::MatchFilter *	filter = `nullptr`
	)

Definition at line 229 of file qgssnappingutils.cpp.

void QgsSnappingUtils::toggleEnabled ( )

slot

Toggles the state of snapping.

Since: QGIS 3.0

Definition at line 460 of file qgssnappingutils.cpp.

Property Documentation

QgsSnappingConfig QgsSnappingUtils::config

readwrite

Definition at line 51 of file qgssnappingutils.h.

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

/build/qgis-3.4.15+24xenial/src/core/qgssnappingutils.h
/build/qgis-3.4.15+24xenial/src/core/qgssnappingutils.cpp

Classes

Public Types

Public Slots

Signals

Public Member Functions

Protected Member Functions

Properties

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Property Documentation