Base class for providing data for QgsMeshLayer. More...

#include <qgsmeshdataprovider.h>

Inheritance diagram for QgsMeshDataProvider:

[legend]

Signals
void	datasetGroupsAdded (int count)
	Emitted when some new dataset groups have been added.

Signals inherited from QgsDataProvider
void	dataChanged ()
	Emitted whenever a change is made to the data provider which may have caused changes in the provider's data OUTSIDE of QGIS.

void	fullExtentCalculated ()
	Emitted whenever a deferred extent calculation is completed by the provider.

void	notify (const QString &msg)
	Emitted when the datasource issues a notification.

Public Member Functions
	QgsMeshDataProvider (const QString &uri, const QgsDataProvider::ProviderOptions &providerOptions, QgsDataProvider::ReadFlags flags=QgsDataProvider::ReadFlags())
	Ctor.

virtual void	close ()=0
	Closes the data provider and free every resources used.

virtual QgsMeshDriverMetadata	driverMetadata () const
	Returns the mesh driver metadata of the provider.

void	setTemporalUnit (Qgis::TemporalUnit unit)
	Sets the temporal unit of the provider and reload data if it changes.

const QgsMeshDataProviderTemporalCapabilities *	temporalCapabilities () const override
	Returns the provider's temporal capabilities.

QgsMeshDataProviderTemporalCapabilities *	temporalCapabilities () override
	Returns the provider's temporal capabilities.

Public Member Functions inherited from QgsDataProvider
	QgsDataProvider (const QString &uri=QString(), const QgsDataProvider::ProviderOptions &providerOptions=QgsDataProvider::ProviderOptions(), QgsDataProvider::ReadFlags flags=QgsDataProvider::ReadFlags())
	Create a new dataprovider with the specified in the uri.

virtual QgsCoordinateReferenceSystem	crs () const =0
	Returns the coordinate system for the data source.

virtual QString	dataComment () const
	Returns a short comment for the data that this provider is providing access to (e.g.

virtual QString	dataSourceUri (bool expandAuthConfig=false) const
	Gets the data source specification.

virtual QDateTime	dataTimestamp () const
	Current time stamp of data source.

virtual QString	description () const =0
	Returns description.

virtual QgsDataProviderElevationProperties *	elevationProperties ()
	Returns the provider's elevation properties.

virtual const QgsDataProviderElevationProperties *	elevationProperties () const
	Returns the provider's elevation properties.

virtual bool	enterUpdateMode ()
	Enter update mode.

virtual QgsError	error () const
	Gets current status error.

virtual QgsRectangle	extent () const =0
	Returns the extent of the layer.

virtual QgsBox3D	extent3D () const
	Returns the 3D extent of the layer.

virtual QString	fileRasterFilters () const
	Returns raster file filter string.

virtual QString	fileVectorFilters () const
	Returns vector file filter string.

virtual Qgis::DataProviderFlags	flags () const
	Returns the generic data provider flags.

virtual QString	htmlMetadata () const
	Obtain a formatted HTML string containing assorted metadata for this data provider.

virtual void	invalidateConnections (const QString &connection)
	Invalidate connections corresponding to specified name.

virtual bool	isValid () const =0
	Returns `true` if this is a valid layer.

virtual QgsLayerMetadata	layerMetadata () const
	Returns layer metadata collected from the provider's source.

virtual bool	leaveUpdateMode ()
	Leave update mode.

virtual QString	name () const =0
	Returns a provider name.

QVariant	providerProperty (int property, const QVariant &defaultValue) const
	Gets the current value of a certain provider property.

QVariant	providerProperty (ProviderProperty property, const QVariant &defaultValue=QVariant()) const
	Gets the current value of a certain provider property.

virtual void	reloadData ()
	Reloads the data from the source for providers with data caches to synchronize, changes in the data source, feature counts and other specific actions.

virtual bool	renderInPreview (const QgsDataProvider::PreviewContext &context)
	Returns whether the layer must be rendered in preview jobs.

virtual void	setDataSourceUri (const QString &uri)
	Set the data source specification.

virtual void	setLayerOrder (const QStringList &layers)
	Reorder the list of layer names to be rendered by this provider (in order from bottom to top)

virtual void	setListening (bool isListening)
	Set whether the provider will listen to datasource notifications If set, the provider will issue notify signals.

void	setProviderProperty (int property, const QVariant &value)
	Allows setting arbitrary properties on the provider.

void	setProviderProperty (ProviderProperty property, const QVariant &value)
	Allows setting arbitrary properties on the provider.

virtual void	setSubLayerVisibility (const QString &name, bool vis)
	Set the visibility of the given sublayer name.

virtual bool	setSubsetString (const QString &subset, bool updateFeatureCount=true)
	Set the subset string used to create a subset of features in the layer.

virtual void	setTransformContext (const QgsCoordinateTransformContext &transformContext)
	Sets data coordinate transform context to transformContext.

void	setUri (const QgsDataSourceUri &uri)
	Set the data source specification.

void	setUri (const QString &uri)
	Set the data source specification.

virtual Qgis::ProviderStyleStorageCapabilities	styleStorageCapabilities () const
	Returns the style storage capabilities.

virtual uint	subLayerCount () const
	Returns the number of layers for the current data source.

virtual QStringList	subLayers () const
	Sub-layers handled by this provider, in order from bottom to top.

virtual QStringList	subLayerStyles () const
	Sub-layer styles for each sub-layer handled by this provider, in order from bottom to top.

virtual QString	subsetString () const
	Returns the subset definition string (typically sql) currently in use by the layer and used by the provider to limit the feature set.

virtual bool	supportsSubsetString () const
	Returns `true` if the provider supports setting of subset strings.

virtual QDateTime	timestamp () const
	Time stamp of data source in the moment when data/metadata were loaded by provider.

QgsCoordinateTransformContext	transformContext () const
	Returns data provider coordinate transform context.

virtual void	updateExtents ()
	Update the extents of the layer.

QgsDataSourceUri	uri () const
	Gets the data source specification.

virtual bool	writeLayerMetadata (const QgsLayerMetadata &metadata)
	Writes layer metadata to the underlying provider source.

Public Member Functions inherited from QgsMeshDataSourceInterface
virtual	~QgsMeshDataSourceInterface ()=default
	Dtor.

bool	contains (const QgsMesh::ElementType &type) const
	Returns whether the mesh contains at mesh elements of given type.

virtual int	edgeCount () const =0
	Returns number of edges in the native mesh.

virtual int	faceCount () const =0
	Returns number of faces in the native mesh.

virtual int	maximumVerticesCountPerFace () const
	Returns the maximum number of vertices per face supported by the current mesh, if returns 0, the number of vertices is unlimited.

virtual void	populateMesh (QgsMesh *mesh) const =0
	Populates the mesh vertices, edges and faces.

virtual bool	saveMeshFrame (const QgsMesh &mesh)=0
	Saves the mesh frame to the source.

virtual int	vertexCount () const =0
	Returns number of vertices in the native mesh.

Public Member Functions inherited from QgsMeshDatasetSourceInterface
	QgsMeshDatasetSourceInterface ()

virtual	~QgsMeshDatasetSourceInterface ()=default
	Dtor.

virtual bool	addDataset (const QString &uri)=0
	Associate dataset with the mesh.

virtual QgsMeshDataBlock	areFacesActive (QgsMeshDatasetIndex index, int faceIndex, int count) const =0
	Returns whether the faces are active for particular dataset.

virtual QgsMesh3DDataBlock	dataset3dValues (QgsMeshDatasetIndex index, int faceIndex, int count) const =0
	Returns N vector/scalar values from the face index from the dataset for 3d stacked meshes.

virtual int	datasetCount (int groupIndex) const =0
	Returns number of datasets loaded in the group.

int	datasetCount (QgsMeshDatasetIndex index) const
	Returns number of datasets loaded in the group.

virtual int	datasetGroupCount () const =0
	Returns number of datasets groups loaded.

virtual QgsMeshDatasetGroupMetadata	datasetGroupMetadata (int groupIndex) const =0
	Returns dataset group metadata.

QgsMeshDatasetGroupMetadata	datasetGroupMetadata (QgsMeshDatasetIndex index) const
	Returns dataset group metadata.

QgsMeshDatasetIndex	datasetIndexAtTime (const QDateTime &referenceTime, int groupIndex, qint64 time, QgsMeshDataProviderTemporalCapabilities::MatchingTemporalDatasetMethod method) const
	Returns the dataset index of the dataset in a specific dataset group at time from the reference time.

QList< QgsMeshDatasetIndex >	datasetIndexInTimeInterval (const QDateTime &referenceTime, int groupIndex, qint64 time1, qint64 time2) const
	Returns a list of dataset indexes of the dataset in a specific dataset group that are between time1 and time2 from the reference time.

virtual QgsMeshDatasetMetadata	datasetMetadata (QgsMeshDatasetIndex index) const =0
	Returns dataset metadata.

virtual QgsMeshDatasetValue	datasetValue (QgsMeshDatasetIndex index, int valueIndex) const =0
	Returns vector/scalar value associated with the index from the dataset To read multiple continuous values, use datasetValues()

virtual QgsMeshDataBlock	datasetValues (QgsMeshDatasetIndex index, int valueIndex, int count) const =0
	Returns N vector/scalar values from the index from the dataset.

virtual QStringList	extraDatasets () const =0
	Returns list of additional dataset file URIs added using addDataset() calls.

virtual bool	isFaceActive (QgsMeshDatasetIndex index, int faceIndex) const =0
	Returns whether the face is active for particular dataset.

virtual bool	persistDatasetGroup (const QString &outputFilePath, const QString &outputDriver, const QgsMeshDatasetGroupMetadata &meta, const QVector< QgsMeshDataBlock > &datasetValues, const QVector< QgsMeshDataBlock > &datasetActive, const QVector< double > &times)=0
	Creates a new dataset group from a data and persists it into a destination path.

virtual bool	persistDatasetGroup (const QString &outputFilePath, const QString &outputDriver, QgsMeshDatasetSourceInterface *source, int datasetGroupIndex)=0
	Saves a an existing dataset group provided by source to a file with a specified driver.

virtual Q_DECL_DEPRECATED bool	persistDatasetGroup (const QString &path, const QgsMeshDatasetGroupMetadata &meta, const QVector< QgsMeshDataBlock > &datasetValues, const QVector< QgsMeshDataBlock > &datasetActive, const QVector< double > &times)
	Creates a new dataset group from a data and persists it into a destination path.

Additional Inherited Members
Public Types inherited from QgsDataProvider
enum	ProviderProperty { EvaluateDefaultValues , CustomData = 3000 }
	Properties are used to pass custom configuration options into data providers. More...

enum	ReadFlag { FlagTrustDataSource = 1 << 0 , SkipFeatureCount = 1 << 1 , FlagLoadDefaultStyle = 1 << 2 , SkipGetExtent = 1 << 3 , SkipFullScan = 1 << 4 , ForceReadOnly = 1 << 5 , SkipCredentialsRequest = 1 << 6 , ParallelThreadLoading = 1 << 7 }
	Flags which control dataprovider construction. More...

Static Public Member Functions inherited from QgsDataProvider
static QString	sublayerSeparator ()
	String sequence used for separating components of sublayers strings.

Protected Member Functions inherited from QgsDataProvider
void	appendError (const QgsErrorMessage &message)
	Add error message.

void	setError (const QgsError &error)
	Sets error message.

Protected Attributes inherited from QgsDataProvider
QgsError	mError
	Error.

QgsDataProvider::ReadFlags	mReadFlags = QgsDataProvider::ReadFlags()
	Read flags. It's up to the subclass to respect these when needed.

QDateTime	mTimestamp
	Timestamp of data in the moment when the data were loaded by provider.

Protected Attributes inherited from QgsMeshDatasetSourceInterface
std::unique_ptr< QgsMeshDataProviderTemporalCapabilities >	mTemporalCapabilities

Detailed Description

Base class for providing data for QgsMeshLayer.

Responsible for reading native mesh data

Note: The API is considered EXPERIMENTAL and can be changed without a notice

Since: QGIS 3.2

Definition at line 440 of file qgsmeshdataprovider.h.

Constructor & Destructor Documentation

◆ QgsMeshDataProvider()

QgsMeshDataProvider::QgsMeshDataProvider	(	const QString &	uri,
		const QgsDataProvider::ProviderOptions &	providerOptions,
		QgsDataProvider::ReadFlags	flags = `QgsDataProvider::ReadFlags()`
	)

Ctor.

Definition at line 23 of file qgsmeshdataprovider.cpp.

Member Function Documentation

◆ close()

virtual void QgsMeshDataProvider::close ( )

pure virtual

Closes the data provider and free every resources used.

Since: QGIS 3.22

◆ datasetGroupsAdded

void QgsMeshDataProvider::datasetGroupsAdded ( int count )

signal

Emitted when some new dataset groups have been added.

◆ driverMetadata()

QgsMeshDriverMetadata QgsMeshDataProvider::driverMetadata ( ) const

virtual

Returns the mesh driver metadata of the provider.

Returns: the mesh driver metadata of the provider

Since: QGIS 3.22

Definition at line 53 of file qgsmeshdataprovider.cpp.

◆ setTemporalUnit()

void QgsMeshDataProvider::setTemporalUnit ( Qgis::TemporalUnit unit )

Sets the temporal unit of the provider and reload data if it changes.

Parameters

unit	the temporal unit

Since: QGIS 3.14

Definition at line 43 of file qgsmeshdataprovider.cpp.

◆ temporalCapabilities() [1/2]

const QgsMeshDataProviderTemporalCapabilities * QgsMeshDataProvider::temporalCapabilities ( ) const

overridevirtual

Returns the provider's temporal capabilities.

This may be nullptr, depending on the data provider.

Since: QGIS 3.14

Reimplemented from QgsDataProvider.

Definition at line 36 of file qgsmeshdataprovider.cpp.

◆ temporalCapabilities() [2/2]

QgsMeshDataProviderTemporalCapabilities * QgsMeshDataProvider::temporalCapabilities ( )