Base class for raster data providers. More...

#include <qgsrasterdataprovider.h>

Inheritance diagram for QgsRasterDataProvider:

[legend]

Classes
struct	VirtualRasterInputLayers
	Struct that stores information of the raster used in QgsVirtualRasterProvider for the calculations, this struct is stored in the DecodedUriParameters. More...

struct	VirtualRasterParameters
	Struct that stores the information about the parameters that should be given to the QgsVirtualRasterProvider through the QgsRasterDataProvider::DecodedUriParameters. More...

Public Types
enum class	ResamplingMethod { Nearest , Bilinear , Cubic , CubicSpline , Lanczos , Average , Mode , Gauss }
	Resampling method for provider-level resampling. More...

enum	TransformType { TransformImageToLayer , TransformLayerToImage }
	Types of transformation in transformCoordinates() function. More...

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...

typedef QFlags< ReadFlag >	ReadFlags

Signals
void	statusChanged (const QString &) const
	Emit a message to be displayed on status bar, usually used by network providers (WMS,WCS)

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
	QgsRasterDataProvider ()

	QgsRasterDataProvider (const QString &uri, const QgsDataProvider::ProviderOptions &providerOptions=QgsDataProvider::ProviderOptions(), QgsDataProvider::ReadFlags flags=QgsDataProvider::ReadFlags())
	Constructor for QgsRasterDataProvider.

QgsRasterAttributeTable *	attributeTable (int bandNumber) const
	Returns the (possibly NULL) attribute table for the specified bandNumber.

virtual QString	bandDescription (int bandNumber)
	Returns the description for band bandNumber, or an empty string if the band is not valid or has not description.

virtual double	bandOffset (int bandNo) const
	Read band offset for raster value.

virtual double	bandScale (int bandNo) const
	Read band scale for raster value.

QgsRasterBlock *	block (int bandNo, const QgsRectangle &boundingBox, int width, int height, QgsRasterBlockFeedback *feedback=nullptr) override
	Read block of data using given extent and size.

virtual QList< QgsRasterPyramid >	buildPyramidList (const QList< int > &overviewList=QList< int >())
	Returns the raster layers pyramid list.

virtual QString	buildPyramids (const QList< QgsRasterPyramid > &pyramidList, const QString &resamplingMethod="NEAREST", Qgis::RasterPyramidFormat format=Qgis::RasterPyramidFormat::GeoTiff, const QStringList &configOptions=QStringList(), QgsRasterBlockFeedback *feedback=nullptr)
	Creates pyramid overviews.

QgsRasterDataProvider *	clone () const override=0
	Clone itself, create deep copy.

virtual Qgis::RasterColorInterpretation	colorInterpretation (int bandNo) const
	Returns data type for the band specified by number.

QString	colorInterpretationName (int bandNo) const override
	Returns the name of the color interpretation for the specified bandNumber.

QString	colorName (Qgis::RasterColorInterpretation colorInterpretation) const
	Returns a string color name representation of a color interpretation.

virtual QList< QgsColorRampShader::ColorRampItem >	colorTable (int bandNo) const

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

Qgis::DataType	dataType (int bandNo) const override=0
	Returns data type for the band specified by number.

int	dpi () const
	Returns the dpi of the output device.

const QgsRasterDataProviderElevationProperties *	elevationProperties () const override
	Returns the provider's elevation properties.

QgsRasterDataProviderElevationProperties *	elevationProperties () override
	Returns the provider's elevation properties.

virtual bool	enableProviderResampling (bool enable)
	Enable or disable provider-level resampling.

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

virtual QgsFields	fields () const
	Returns the fields of the raster layer for data providers that expose them, the default implementation returns an empty list.

virtual QImage	getLegendGraphic (double scale=0, bool forceRefresh=false, const QgsRectangle *visibleExtent=nullptr)
	Returns the legend rendered as pixmap.

virtual QgsImageFetcher *	getLegendGraphicFetcher (const QgsMapSettings *mapSettings)
	Returns a new image downloader for the raster legend.

bool	hasPyramids ()
	Returns `true` if raster has at least one existing pyramid.

virtual QgsRasterIdentifyResult	identify (const QgsPointXY &point, Qgis::RasterIdentifyFormat format, const QgsRectangle &boundingBox=QgsRectangle(), int width=0, int height=0, int dpi=96)
	Identify raster value(s) found on the point position.

virtual bool	ignoreExtents () const
	Returns `true` if the extents reported by the data provider are not reliable and it's possible that there is renderable content outside of these extents.

virtual bool	isEditable () const
	Checks whether the provider is in editing mode, i.e.

bool	isProviderResamplingEnabled () const
	Returns whether provider-level resampling is enabled.

virtual QString	lastError ()=0
	Returns the verbose error text for the last error in this provider.

virtual QString	lastErrorFormat ()
	Returns the format of the error text for the last error in this provider.

virtual QString	lastErrorTitle ()=0
	Returns the caption error text for the last error in this provider.

double	maxOversampling () const
	Returns maximum oversampling factor for zoomed-out operations.

virtual QList< double >	nativeResolutions () const
	Returns a list of native resolutions if available, i.e.

virtual Qgis::RasterProviderCapabilities	providerCapabilities () const
	Returns flags containing the supported capabilities of the data provider.

bool	readFileBasedAttributeTable (int bandNumber, const QString &path, QString *errorMessage=nullptr)
	Loads the filesystem-based attribute table for the specified bandNumber from path, optionally reporting any error in errorMessage, returns `true` on success.

virtual bool	readNativeAttributeTable (QString *errorMessage=nullptr)
	Reads the native attribute table, optionally reporting any error in errorMessage, returns `true` on success.

void	readXml (const QDomElement &filterElem) override
	Sets base class members from xml. Usually called from create() methods of subclasses.

virtual bool	reload ()
	Reload data (data could change)

virtual bool	remove ()
	Remove dataset.

void	removeAttributeTable (int bandNumber)
	Remove the attribute table for the specified bandNumber.

virtual double	sample (const QgsPointXY &point, int band, bool *ok=nullptr, const QgsRectangle &boundingBox=QgsRectangle(), int width=0, int height=0, int dpi=96)
	Samples a raster value from the specified band found at the point position.

void	setAttributeTable (int bandNumber, QgsRasterAttributeTable *attributeTable)
	Set the attribute table to attributeTable for the specified bandNumber, if the attributeTable is NULL any existing attribute table for the specified band will be removed.

void	setDpi (int dpi)
	Sets the output device resolution.

virtual bool	setEditable (bool enabled)
	Turns on/off editing mode of the provider.

bool	setInput (QgsRasterInterface *input) override
	Set input.

virtual bool	setMaxOversampling (double factor)
	Sets maximum oversampling factor for zoomed-out operations.

virtual bool	setNoDataValue (int bandNo, double noDataValue)
	Set no data value on created dataset.

virtual void	setUserNoDataValue (int bandNo, const QgsRasterRangeList &noData)

virtual void	setUseSourceNoDataValue (int bandNo, bool use)
	Sets the source nodata value usage.

virtual bool	setZoomedInResamplingMethod (ResamplingMethod method)
	Set resampling method to apply for zoomed-in operations.

virtual bool	setZoomedOutResamplingMethod (ResamplingMethod method)
	Set resampling method to apply for zoomed-out operations.

Qgis::DataType	sourceDataType (int bandNo) const override=0
	Returns source data type for the band specified by number, source data type may be shorter than dataType.

virtual bool	sourceHasNoDataValue (int bandNo) const
	Returns `true` if source band has no data value.

virtual double	sourceNoDataValue (int bandNo) const
	Value representing no data value.

virtual int	stepHeight () const
	Step height for raster iterations.

virtual int	stepWidth () const
	Step width for raster iterations.

QStringList	subLayers () const override
	Returns the sublayers of this layer - useful for providers that manage their own layers, such as WMS.

virtual bool	supportsLegendGraphic () const
	Returns whether the provider supplies a legend graphic.

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

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

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

virtual QgsPoint	transformCoordinates (const QgsPoint &point, TransformType type)
	Transforms coordinates between source image coordinate space [0..width]x[0..height] and layer coordinate space (georeferenced coordinates).

virtual QgsRasterRangeList	userNoDataValues (int bandNo) const
	Returns a list of user no data value ranges.

virtual bool	useSourceNoDataValue (int bandNo) const
	Returns the source nodata value usage.

virtual QString	validateCreationOptions (const QStringList &createOptions, const QString &format)
	Validates creation options for a specific dataset and destination format.

virtual QString	validatePyramidsConfigOptions (Qgis::RasterPyramidFormat pyramidsFormat, const QStringList &configOptions, const QString &fileFormat)
	Validates pyramid creation options for a specific dataset and destination format.

virtual bool	write (const void *data, int band, int width, int height, int xOffset, int yOffset)
	Writes into the provider datasource.

bool	writeBlock (QgsRasterBlock *block, int band, int xOffset=0, int yOffset=0)
	Writes pixel data from a raster block into the provider data source.

bool	writeFileBasedAttributeTable (int bandNumber, const QString &path, QString *errorMessage=nullptr) const
	Writes the filesystem-based attribute table for the specified bandNumber to path, optionally reporting any error in errorMessage, returns `true` on success.

virtual bool	writeNativeAttributeTable (QString *errorMessage=nullptr)
	Writes the native attribute table, optionally reporting any error in errorMessage, returns `true` on success.

void	writeXml (QDomDocument &doc, QDomElement &parentElem) const override
	Write base class members to xml.

ResamplingMethod	zoomedInResamplingMethod () const
	Returns resampling method for zoomed-in operations.

ResamplingMethod	zoomedOutResamplingMethod () const
	Returns resampling method for zoomed-out operations.

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 QString	description () const =0
	Returns description.

virtual bool	enterUpdateMode ()
	Enter update mode.

virtual QgsError	error () const
	Gets current status error.

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	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.

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 QgsRasterInterface
	QgsRasterInterface (QgsRasterInterface *input=nullptr)

virtual	~QgsRasterInterface ()=default

virtual int	bandCount () const =0
	Gets number of bands.

Q_DECL_DEPRECATED QgsRasterBandStats	bandStatistics (int bandNo, int stats, const QgsRectangle &extent=QgsRectangle(), int sampleSize=0, QgsRasterBlockFeedback *feedback=nullptr)
	Returns the band statistics.

virtual QgsRasterBandStats	bandStatistics (int bandNo, Qgis::RasterBandStatistics stats=Qgis::RasterBandStatistic::All, const QgsRectangle &extent=QgsRectangle(), int sampleSize=0, QgsRasterBlockFeedback *feedback=nullptr)
	Returns the band statistics.

virtual Qgis::RasterInterfaceCapabilities	capabilities () const
	Returns the capabilities supported by the interface.

Q_DECL_DEPRECATED QString	capabilitiesString () const
	Returns the raster interface capabilities in friendly format.

virtual void	cumulativeCut (int bandNo, double lowerCount, double upperCount, double &lowerValue, double &upperValue, const QgsRectangle &extent=QgsRectangle(), int sampleSize=0)
	Find values for cumulative pixel count cut.

int	dataTypeSize (int bandNo) const
	Returns the size (in bytes) for the data type for the specified band.

QString	displayBandName (int bandNumber) const
	Generates a friendly, descriptive name for the specified bandNumber.

virtual QString	generateBandName (int bandNumber) const
	helper function to create zero padded band names

virtual bool	hasHistogram (int bandNo, int binCount, double minimum=std::numeric_limits< double >::quiet_NaN(), double maximum=std::numeric_limits< double >::quiet_NaN(), const QgsRectangle &extent=QgsRectangle(), int sampleSize=0, bool includeOutOfRange=false)
	Returns `true` if histogram is available (cached, already calculated)

Q_DECL_DEPRECATED bool	hasStatistics (int bandNo, int stats, const QgsRectangle &extent=QgsRectangle(), int sampleSize=0)
	Returns `true` if histogram is available (cached, already calculated).

virtual bool	hasStatistics (int bandNo, Qgis::RasterBandStatistics stats=Qgis::RasterBandStatistic::All, const QgsRectangle &extent=QgsRectangle(), int sampleSize=0)
	Returns `true` if histogram is available (cached, already calculated).

virtual QgsRasterHistogram	histogram (int bandNo, int binCount=0, double minimum=std::numeric_limits< double >::quiet_NaN(), double maximum=std::numeric_limits< double >::quiet_NaN(), const QgsRectangle &extent=QgsRectangle(), int sampleSize=0, bool includeOutOfRange=false, QgsRasterBlockFeedback *feedback=nullptr)
	Returns a band histogram.

virtual QgsRasterInterface *	input () const
	Current input.

virtual bool	on () const
	Returns whether the interface is on or off.

virtual void	setOn (bool on)
	Sets whether the interface is on or off.

virtual QgsRasterInterface *	sourceInput ()
	Gets source / raw input, the first in pipe, usually provider.

virtual const QgsRasterInterface *	sourceInput () const
	Gets source / raw input, the first in pipe, usually provider.

virtual int	xBlockSize () const
	Gets block size.

virtual int	xSize () const
	Gets raster size.

virtual int	yBlockSize () const

virtual int	ySize () const

Static Public Member Functions
static QgsRasterDataProvider *	create (const QString &providerKey, const QString &uri, const QString &format, int nBands, Qgis::DataType type, int width, int height, double *geoTransform, const QgsCoordinateReferenceSystem &crs, const QStringList &createOptions=QStringList())
	Creates a new dataset with mDataSourceURI.

static QgsRasterDataProvider::VirtualRasterParameters	decodeVirtualRasterProviderUri (const QString &uri, bool *ok=nullptr)
	Decodes the URI returning a struct with all the parameters for QgsVirtualRasterProvider class.

static QString	encodeVirtualRasterProviderUri (const VirtualRasterParameters &parts)
	Encodes the URI starting from the struct .

static Qgis::RasterIdentifyFormat	identifyFormatFromName (const QString &formatName)
	Converts a string formatName to a raster identify format.

static QString	identifyFormatLabel (Qgis::RasterIdentifyFormat format)
	Converts a raster identify format to a translated string label.

static QString	identifyFormatName (Qgis::RasterIdentifyFormat format)
	Converts a raster identify format to a string name.

static Qgis::RasterInterfaceCapability	identifyFormatToCapability (Qgis::RasterIdentifyFormat format)
	Converts a raster identify format to a capability.

static QList< QPair< QString, QString > >	pyramidResamplingMethods (const QString &providerKey)
	Returns a list of pyramid resampling method name and label pairs for given provider.

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

Protected Member Functions
void	copyBaseSettings (const QgsRasterDataProvider &other)
	Copy member variables from other raster data provider. Useful for implementation of clone() method in subclasses.

virtual bool	readBlock (int bandNo, int xBlock, int yBlock, void *data)
	Reads a block of raster data into data.

virtual bool	readBlock (int bandNo, QgsRectangle const &viewExtent, int width, int height, void data, QgsRasterBlockFeedback feedback=nullptr)
	Reads a block of raster data into data, using the given extent and size.

bool	userNoDataValuesContains (int bandNo, double value) const
	Returns `true` if user no data contains value.

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

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

Protected Member Functions inherited from QgsRasterInterface
void	initHistogram (QgsRasterHistogram &histogram, int bandNo, int binCount, double minimum=std::numeric_limits< double >::quiet_NaN(), double maximum=std::numeric_limits< double >::quiet_NaN(), const QgsRectangle &boundingBox=QgsRectangle(), int sampleSize=0, bool includeOutOfRange=false)
	Fill in histogram defaults if not specified.

Q_DECL_DEPRECATED void	initStatistics (QgsRasterBandStats &statistics, int bandNo, int stats, const QgsRectangle &boundingBox=QgsRectangle(), int binCount=0) const
	Fill in statistics defaults if not specified.

void	initStatistics (QgsRasterBandStats &statistics, int bandNo, Qgis::RasterBandStatistics stats=Qgis::RasterBandStatistic::All, const QgsRectangle &boundingBox=QgsRectangle(), int binCount=0) const
	Fill in statistics defaults if not specified.

Protected Attributes
int	mDpi = -1
	Dots per inch.

QgsRectangle	mExtent

double	mMaxOversampling = 2.0
	Maximum boundary for oversampling (to avoid too much data traffic). Default: 2.0.

bool	mProviderResamplingEnabled = false
	Whether provider resampling is enabled.

QList< bool >	mSrcHasNoDataValue
	Source no data value exists.

QList< double >	mSrcNoDataValue
	Source no data value is available and is set to be used or internal no data is available.

QList< QgsRasterRangeList >	mUserNoDataValue
	List of lists of user defined additional no data values for each band, indexed from 0.

QList< bool >	mUseSrcNoDataValue
	Use source nodata value.

ResamplingMethod	mZoomedInResamplingMethod = ResamplingMethod::Nearest
	Resampling method for zoomed in pixel extraction.

ResamplingMethod	mZoomedOutResamplingMethod = ResamplingMethod::Nearest
	Resampling method for zoomed out pixel extraction.

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 QgsRasterInterface
QList< QgsRasterHistogram >	mHistograms
	List of cached histograms, all bands mixed.

QgsRasterInterface *	mInput = nullptr

bool	mOn = true

QList< QgsRasterBandStats >	mStatistics
	List of cached statistics, all bands mixed.

Detailed Description

Base class for raster data providers.

Definition at line 88 of file qgsrasterdataprovider.h.

Member Enumeration Documentation

◆ ResamplingMethod

enum class QgsRasterDataProvider::ResamplingMethod

strong

Resampling method for provider-level resampling.

Since: QGIS 3.16

Enumerator
Nearest	Nearest-neighbour resampling.
Bilinear	Bilinear (2x2 kernel) resampling.
Cubic	Cubic Convolution Approximation (4x4 kernel) resampling.
CubicSpline	Cubic B-Spline Approximation (4x4 kernel)
Lanczos	Lanczos windowed sinc interpolation (6x6 kernel)
Average	Average resampling.
Mode	Mode (selects the value which appears most often of all the sampled points)
Gauss	Gauss blurring.

Definition at line 677 of file qgsrasterdataprovider.h.

◆ TransformType

enum QgsRasterDataProvider::TransformType

Types of transformation in transformCoordinates() function.

Since: QGIS 3.14

Enumerator
TransformImageToLayer	Transforms image coordinates to layer (georeferenced) coordinates.
TransformLayerToImage	Transforms layer (georeferenced) coordinates to image coordinates.

Definition at line 630 of file qgsrasterdataprovider.h.

Constructor & Destructor Documentation

◆ QgsRasterDataProvider() [1/2]

QgsRasterDataProvider::QgsRasterDataProvider ( )

Definition at line 235 of file qgsrasterdataprovider.cpp.

◆ QgsRasterDataProvider() [2/2]

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

Constructor for QgsRasterDataProvider.

The uri argument gives a provider-specific uri indicating the underlying data source and it's parameters.

The options argument specifies generic provider options and since QGIS 3.16 creation flags are specified within the flags value.

Definition at line 244 of file qgsrasterdataprovider.cpp.

Member Function Documentation

◆ attributeTable()

QgsRasterAttributeTable * QgsRasterDataProvider::attributeTable ( int bandNumber ) const

Returns the (possibly NULL) attribute table for the specified bandNumber.

Since: QGIS 3.30

Definition at line 700 of file qgsrasterdataprovider.cpp.

◆ bandDescription()

QString QgsRasterDataProvider::bandDescription ( int bandNumber )

virtual

Returns the description for band bandNumber, or an empty string if the band is not valid or has not description.

The default implementation returns an empty string.

Since: QGIS 3.34

Definition at line 766 of file qgsrasterdataprovider.cpp.

◆ bandOffset()

virtual double QgsRasterDataProvider::bandOffset ( int bandNo ) const

inlinevirtual

Read band offset for raster value.

Definition at line 217 of file qgsrasterdataprovider.h.

◆ bandScale()

virtual double QgsRasterDataProvider::bandScale ( int bandNo ) const

inlinevirtual

Read band scale for raster value.

Definition at line 212 of file qgsrasterdataprovider.h.

◆ block()

QgsRasterBlock * QgsRasterDataProvider::block	(	int	bandNo,
		const QgsRectangle &	boundingBox,
		int	width,
		int	height,
		QgsRasterBlockFeedback *	feedback = `nullptr`
	)

overridevirtual

Read block of data using given extent and size.

Implements QgsRasterInterface.

Definition at line 50 of file qgsrasterdataprovider.cpp.

◆ buildPyramidList()

virtual QList< QgsRasterPyramid > QgsRasterDataProvider::buildPyramidList ( const QList< int > & overviewList = QList<int>() )

inlinevirtual

Returns the raster layers pyramid list.

This method returns a list of pyramid layers which are valid for the data provider. The returned list is a complete list of all possible layers, and includes both pyramids layers which currently exist and layers which have not yet been constructed. To know which of the pyramid layers ACTUALLY exists you need to look at the QgsRasterPyramid::getExists() member for each value in the list.

The returned list is suitable for passing to the buildPyramids() method. First, modify the returned list by calling QgsRasterPyramid::setBuild( \c true ) for every layer you want to create pyramids for, and then pass the modified list to buildPyramids().

Parameters

overviewList used to construct the pyramid list (optional), when empty the list is defined by the provider.

See also: buildPyramids(); hasPyramids()

Definition at line 346 of file qgsrasterdataprovider.h.

◆ buildPyramids()

virtual QString QgsRasterDataProvider::buildPyramids	(	const QList< QgsRasterPyramid > &	pyramidList,
		const QString &	resamplingMethod = `"NEAREST"`,
		Qgis::RasterPyramidFormat	format = `Qgis::RasterPyramidFormat::GeoTiff`,
		const QStringList &	configOptions = `QStringList()`,
		QgsRasterBlockFeedback *	feedback = `nullptr`
	)

inlinevirtual

Creates pyramid overviews.

Parameters

pyramidList	a list of QgsRasterPyramids to create overviews for. The QgsRasterPyramid::setBuild() flag should be set to `true` for every layer where pyramids are desired.
resamplingMethod	resampling method to use when creating the pyramids. The pyramidResamplingMethods() method can be used to retrieve a list of valid resampling methods available for specific raster data providers.
format	raster pyramid format.
configOptions	optional configuration options which are passed to the specific data provider for use during pyramid creation.
feedback	optional feedback argument for progress reports and cancellation support.

See also: buildPyramidList(); hasPyramids(); pyramidResamplingMethods()

Definition at line 314 of file qgsrasterdataprovider.h.

◆ clone()

QgsRasterDataProvider * QgsRasterDataProvider::clone ( ) const

overridepure virtual

Clone itself, create deep copy.

Implements QgsRasterInterface.

◆ colorInterpretation()

Qgis::RasterColorInterpretation QgsRasterDataProvider::colorInterpretation ( int bandNo ) const

virtual

Returns data type for the band specified by number.

Definition at line 260 of file qgsrasterdataprovider.cpp.

◆ colorInterpretationName()

QString QgsRasterDataProvider::colorInterpretationName ( int bandNumber ) const

overridevirtual

Returns the name of the color interpretation for the specified bandNumber.

Since: QGIS 3.18

Reimplemented from QgsRasterInterface.

Definition at line 796 of file qgsrasterdataprovider.cpp.

◆ colorName()

QString QgsRasterDataProvider::colorName ( Qgis::RasterColorInterpretation colorInterpretation ) const

inline

Returns a string color name representation of a color interpretation.

Definition at line 142 of file qgsrasterdataprovider.h.

◆ colorTable()

virtual QList< QgsColorRampShader::ColorRampItem > QgsRasterDataProvider::colorTable ( int bandNo ) const

inlinevirtual

Definition at line 241 of file qgsrasterdataprovider.h.

◆ copyBaseSettings()

void QgsRasterDataProvider::copyBaseSettings ( const QgsRasterDataProvider & other )

protected

Copy member variables from other raster data provider. Useful for implementation of clone() method in subclasses.

Definition at line 575 of file qgsrasterdataprovider.cpp.

◆ create()

QgsRasterDataProvider * QgsRasterDataProvider::create	(	const QString &	providerKey,
		const QString &	uri,
		const QString &	format,
		int	nBands,
		Qgis::DataType	type,
		int	width,
		int	height,
		double *	geoTransform,
		const QgsCoordinateReferenceSystem &	crs,
		const QStringList &	createOptions = `QStringList()`
	)

static

Creates a new dataset with mDataSourceURI.

Definition at line 453 of file qgsrasterdataprovider.cpp.

◆ dataTimestamp()

QDateTime QgsRasterDataProvider::dataTimestamp ( ) const

inlineoverridevirtual

Current time stamp of data source.

Reimplemented from QgsDataProvider.

Definition at line 438 of file qgsrasterdataprovider.h.

◆ dataType()

Qgis::DataType QgsRasterDataProvider::dataType ( int bandNo ) const

overridepure virtual

Returns data type for the band specified by number.

Implements QgsRasterInterface.

◆ decodeVirtualRasterProviderUri()

QgsRasterDataProvider::VirtualRasterParameters QgsRasterDataProvider::decodeVirtualRasterProviderUri	(	const QString &	uri,
		bool *	ok = `nullptr`
	)

static

Decodes the URI returning a struct with all the parameters for QgsVirtualRasterProvider class.

Note: used by Virtual Raster Provider only; since QGIS 3.22

Definition at line 803 of file qgsrasterdataprovider.cpp.

◆ dpi()

int QgsRasterDataProvider::dpi ( ) const

inline

Returns the dpi of the output device.

Definition at line 429 of file qgsrasterdataprovider.h.

◆ elevationProperties() [1/2]

const QgsRasterDataProviderElevationProperties * QgsRasterDataProvider::elevationProperties ( ) const

overridevirtual

Returns the provider's elevation properties.

This may be nullptr, depending on the data provider.

Since: QGIS 3.32

Reimplemented from QgsDataProvider.

Definition at line 446 of file qgsrasterdataprovider.cpp.

◆ elevationProperties() [2/2]

QgsRasterDataProviderElevationProperties * QgsRasterDataProvider::elevationProperties ( )

overridevirtual

Returns the provider's elevation properties.

This may be nullptr, depending on the data provider.

Since: QGIS 3.32

Reimplemented from QgsDataProvider.

Definition at line 439 of file qgsrasterdataprovider.cpp.

◆ enableProviderResampling()

virtual bool QgsRasterDataProvider::enableProviderResampling ( bool enable )

inlinevirtual

Enable or disable provider-level resampling.

Returns: true if success

Since: QGIS 3.16

Definition at line 657 of file qgsrasterdataprovider.h.

◆ encodeVirtualRasterProviderUri()

QString QgsRasterDataProvider::encodeVirtualRasterProviderUri ( const VirtualRasterParameters & parts )

static

Encodes the URI starting from the struct .

Note: used by Virtual Raster Provider only; since QGIS 3.22

Definition at line 904 of file qgsrasterdataprovider.cpp.

◆ extent()

QgsRectangle QgsRasterDataProvider::extent ( ) const

overridepure virtual

Returns the extent of the layer.

Warning: This may be expensive to calculate for some data providers, as it may involve additional network requests or in some cases, iterating through all the features in a layer. If the provider returns the Qgis::DataProviderFlag::FastExtent2D flag from the flags() method then the call to extent() is guaranteed to ALWAYS be fast and not involve any additional work.

Implements QgsDataProvider.

◆ fields()

virtual QgsFields QgsRasterDataProvider::fields ( ) const

inlinevirtual

Returns the fields of the raster layer for data providers that expose them, the default implementation returns an empty list.

Since: QGIS 3.14

Definition at line 128 of file qgsrasterdataprovider.h.

◆ getLegendGraphic()

virtual QImage QgsRasterDataProvider::getLegendGraphic	(	double	scale = `0`,
		bool	forceRefresh = `false`,
		const QgsRectangle *	visibleExtent = `nullptr`
	)

inlinevirtual

Returns the legend rendered as pixmap.

This is useful for layers which need to get legend layers remotely as WMS.

Parameters

scale	Optional parameter that is the Scale of the layer
forceRefresh	Optional bool parameter to force refresh getLegendGraphic call
visibleExtent	Visible extent for providers supporting contextual legends, in layer CRS

Note: Parameter visibleExtent added in QGIS 2.8; Not available in Python bindings

Definition at line 272 of file qgsrasterdataprovider.h.

◆ getLegendGraphicFetcher()

virtual QgsImageFetcher * QgsRasterDataProvider::getLegendGraphicFetcher ( const QgsMapSettings * mapSettings )

inlinevirtual

Returns a new image downloader for the raster legend.

Parameters

mapSettings map settings for legend providers supporting contextual legends.

Returns: a download handler or nullptr if the provider does not support legend at all. Ownership of the returned object is transferred to caller.

Definition at line 292 of file qgsrasterdataprovider.h.

◆ hasPyramids()

bool QgsRasterDataProvider::hasPyramids ( )

Returns true if raster has at least one existing pyramid.

The buildPyramidList() method can be used to retrieve additional details about potential and existing pyramid layers.

See also: buildPyramidList(); buildPyramids()

Definition at line 389 of file qgsrasterdataprovider.cpp.

◆ identify()

QgsRasterIdentifyResult QgsRasterDataProvider::identify	(	const QgsPointXY &	point,
		Qgis::RasterIdentifyFormat	format,
		const QgsRectangle &	boundingBox = `QgsRectangle()`,
		int	width = `0`,
		int	height = `0`,
		int	dpi = `96`
	)

virtual

Identify raster value(s) found on the point position.

The context parameters extent, width and height are important to identify on the same zoom level as a displayed map and to do effective caching (WCS). If context params are not specified the highest resolution is used. capabilities() may be used to test if format is supported by provider. Values are set to 'no data' or empty string if point is outside data source extent.

Parameters

point	coordinates in data source CRS
format	result format
boundingBox	context bounding box
width	context width
height	context height
dpi	context dpi

Returns: QgsRaster::IdentifyFormatValue: map of values for each band, keys are band numbers (from 1). QgsRaster::IdentifyFormatFeature: map of QgsRasterFeatureList for each sublayer QgsRaster::IdentifyFormatHtml: map of HTML strings for each sublayer (WMS). Empty if failed or there are no results.

Note: The arbitraryness of the returned document is enforced by WMS standards up to at least v1.3.0

See also: sample(), which is much more efficient for simple "value at point" queries.

Definition at line 271 of file qgsrasterdataprovider.cpp.

◆ identifyFormatFromName()

Qgis::RasterIdentifyFormat QgsRasterDataProvider::identifyFormatFromName ( const QString & formatName )

static

Converts a string formatName to a raster identify format.

See also: identifyFormatName()

Definition at line 513 of file qgsrasterdataprovider.cpp.

◆ identifyFormatLabel()

QString QgsRasterDataProvider::identifyFormatLabel ( Qgis::RasterIdentifyFormat format )

static

Converts a raster identify format to a translated string label.

Definition at line 495 of file qgsrasterdataprovider.cpp.

◆ identifyFormatName()

QString QgsRasterDataProvider::identifyFormatName ( Qgis::RasterIdentifyFormat format )

static

Converts a raster identify format to a string name.

See also: identifyFormatFromName()

Definition at line 477 of file qgsrasterdataprovider.cpp.

◆ identifyFormatToCapability()

Qgis::RasterInterfaceCapability QgsRasterDataProvider::identifyFormatToCapability ( Qgis::RasterIdentifyFormat format )

static

Converts a raster identify format to a capability.

Definition at line 526 of file qgsrasterdataprovider.cpp.

◆ ignoreExtents()

bool QgsRasterDataProvider::ignoreExtents ( ) const

virtual

Returns true if the extents reported by the data provider are not reliable and it's possible that there is renderable content outside of these extents.

Since: QGIS 3.10.0

Definition at line 551 of file qgsrasterdataprovider.cpp.

◆ isEditable()

virtual bool QgsRasterDataProvider::isEditable ( ) const

inlinevirtual

Checks whether the provider is in editing mode, i.e.

raster write operations will be accepted. By default providers are not editable. Use setEditable() method to enable/disable editing.

See also: setEditable(), writeBlock()

Definition at line 445 of file qgsrasterdataprovider.h.

◆ isProviderResamplingEnabled()

bool QgsRasterDataProvider::isProviderResamplingEnabled ( ) const

inline

Returns whether provider-level resampling is enabled.

Note: Resampling is effective only if zoomedInResamplingMethod() and/or zoomedOutResamplingMethod() return non-nearest resampling.

See also: zoomedInResamplingMethod(); zoomedOutResamplingMethod(); maxOversampling()

Since: QGIS 3.16

Definition at line 671 of file qgsrasterdataprovider.h.

◆ lastError()

virtual QString QgsRasterDataProvider::lastError ( )

pure virtual

Returns the verbose error text for the last error in this provider.

If an operation returns 0 (e.g. draw()), this function returns the text of the error associated with the failure. Interactive users of this provider can then, for example, call a QMessageBox to display the contents.

◆ lastErrorFormat()

QString QgsRasterDataProvider::lastErrorFormat ( )

virtual

Returns the format of the error text for the last error in this provider.

Definition at line 357 of file qgsrasterdataprovider.cpp.

◆ lastErrorTitle()

virtual QString QgsRasterDataProvider::lastErrorTitle ( )

pure virtual

Returns the caption error text for the last error in this provider.

If an operation returns 0 (e.g. draw()), this function returns the text of the error associated with the failure. Interactive users of this provider can then, for example, call a QMessageBox to display the contents.

◆ maxOversampling()

double QgsRasterDataProvider::maxOversampling ( ) const

inline

Returns maximum oversampling factor for zoomed-out operations.

Since: QGIS 3.16

Definition at line 729 of file qgsrasterdataprovider.h.

◆ nativeResolutions()

QList< double > QgsRasterDataProvider::nativeResolutions ( ) const

virtual

Returns a list of native resolutions if available, i.e.

map units per pixel at which the raster source was originally created.

Resolutions are calculated in the provider's crs().

Since: QGIS 3.8.0

Definition at line 544 of file qgsrasterdataprovider.cpp.

◆ providerCapabilities()

Qgis::RasterProviderCapabilities QgsRasterDataProvider::providerCapabilities ( ) const

virtual

Returns flags containing the supported capabilities of the data provider.

Definition at line 253 of file qgsrasterdataprovider.cpp.

◆ pyramidResamplingMethods()

QList< QPair< QString, QString > > QgsRasterDataProvider::pyramidResamplingMethods ( const QString & providerKey )

static

Returns a list of pyramid resampling method name and label pairs for given provider.

Definition at line 379 of file qgsrasterdataprovider.cpp.

◆ readBlock() [1/2]

virtual bool QgsRasterDataProvider::readBlock	(	int	bandNo,
		int	xBlock,
		int	yBlock,
		void *	data
	)

inlineprotectedvirtual

Reads a block of raster data into data.

Returns: true if the block was successfully read, or false if an error occurred and the block could not be read.

Note: not available in Python bindings

Definition at line 823 of file qgsrasterdataprovider.h.

◆ readBlock() [2/2]

virtual bool QgsRasterDataProvider::readBlock	(	int	bandNo,
		QgsRectangle const &	viewExtent,
		int	width,
		int	height,
		void *	data,
		QgsRasterBlockFeedback *	feedback = `nullptr`
	)

inlineprotectedvirtual

Reads a block of raster data into data, using the given extent and size.

Returns: true if the block was successfully read, or false if an error occurred and the block could not be read.

Note: not available in Python bindings

Definition at line 831 of file qgsrasterdataprovider.h.

◆ readFileBasedAttributeTable()

bool QgsRasterDataProvider::readFileBasedAttributeTable	(	int	bandNumber,
		const QString &	path,
		QString *	errorMessage = `nullptr`
	)

Loads the filesystem-based attribute table for the specified bandNumber from path, optionally reporting any error in errorMessage, returns true on success.

Returns: true on success

Since: QGIS 3.30

Definition at line 772 of file qgsrasterdataprovider.cpp.

◆ readNativeAttributeTable()

bool QgsRasterDataProvider::readNativeAttributeTable ( QString * errorMessage = nullptr )

virtual

Reads the native attribute table, optionally reporting any error in errorMessage, returns true on success.

The default implementation does nothing and returns false. Data providers that have NativeRasterAttributeTable provider capability will try to read the native attribute table.

Returns: true on success

Since: QGIS 3.30

Definition at line 755 of file qgsrasterdataprovider.cpp.

◆ readXml()

void QgsRasterDataProvider::readXml ( const QDomElement & filterElem )

overridevirtual

Sets base class members from xml. Usually called from create() methods of subclasses.

Reimplemented from QgsRasterInterface.

Definition at line 633 of file qgsrasterdataprovider.cpp.

◆ reload()

virtual bool QgsRasterDataProvider::reload ( )

inlinevirtual

Reload data (data could change)

Definition at line 205 of file qgsrasterdataprovider.h.

◆ remove()

virtual bool QgsRasterDataProvider::remove ( )

inlinevirtual

Remove dataset.

Definition at line 506 of file qgsrasterdataprovider.h.

◆ removeAttributeTable()

void QgsRasterDataProvider::removeAttributeTable ( int bandNumber )

Remove the attribute table for the specified bandNumber.

If the attribute table does not exist this method does nothing.

Since: QGIS 3.30

Definition at line 728 of file qgsrasterdataprovider.cpp.

◆ sample()

double QgsRasterDataProvider::sample	(	const QgsPointXY &	point,
		int	band,
		bool *	ok = `nullptr`,
		const QgsRectangle &	boundingBox = `QgsRectangle()`,
		int	width = `0`,
		int	height = `0`,
		int	dpi = `96`
	)

virtual

Samples a raster value from the specified band found at the point position.

The context parameters boundingBox, width and height are important to identify on the same zoom level as a displayed map and to do effective caching (WCS). If context params are not specified the highest resolution is used.

If ok is specified and the point is outside data source extent, or an invalid band number was specified, then ok will be set to false. In this case the function will return a NaN value.

See also: identify(), which is much more flexible but considerably less efficient.

Since: QGIS 3.4

Definition at line 337 of file qgsrasterdataprovider.cpp.

◆ setAttributeTable()

void QgsRasterDataProvider::setAttributeTable	(	int	bandNumber,
		QgsRasterAttributeTable *	attributeTable
	)

Set the attribute table to attributeTable for the specified bandNumber, if the attributeTable is NULL any existing attribute table for the specified band will be removed.

Note: Ownership of the attribute table is transferred to the provider.

Since: QGIS 3.30

Definition at line 714 of file qgsrasterdataprovider.cpp.

◆ setDpi()

void QgsRasterDataProvider::setDpi ( int dpi )

inline

Sets the output device resolution.

Definition at line 432 of file qgsrasterdataprovider.h.

◆ setEditable()

virtual bool QgsRasterDataProvider::setEditable ( bool enabled )

inlinevirtual

Turns on/off editing mode of the provider.

When in editing mode, it is possible to overwrite data of the provider using writeBlock() calls.

Returns: true if the switch to/from editing mode was successful

Note: Only some providers support editing mode and even those may fail to turn the underlying data source into editing mode, so it is necessary to check the return value whether the operation was successful.

See also: isEditable(), writeBlock()

Definition at line 456 of file qgsrasterdataprovider.h.

◆ setInput()

bool QgsRasterDataProvider::setInput ( QgsRasterInterface * input )

inlineoverridevirtual

Set input.

Returns true if set correctly, false if cannot use that input

Reimplemented from QgsRasterInterface.

Definition at line 116 of file qgsrasterdataprovider.h.

◆ setMaxOversampling()

virtual bool QgsRasterDataProvider::setMaxOversampling ( double factor )

inlinevirtual

Sets maximum oversampling factor for zoomed-out operations.

Returns: true if success

Since: QGIS 3.16

Definition at line 723 of file qgsrasterdataprovider.h.

◆ setNoDataValue()

virtual bool QgsRasterDataProvider::setNoDataValue	(	int	bandNo,
		double	noDataValue
	)

inlinevirtual

Set no data value on created dataset.

Parameters

bandNo	band number
noDataValue	no data value

Definition at line 503 of file qgsrasterdataprovider.h.

◆ setUserNoDataValue()

void QgsRasterDataProvider::setUserNoDataValue	(	int	bandNo,
		const QgsRasterRangeList &	noData
	)

virtual

Definition at line 397 of file qgsrasterdataprovider.cpp.

◆ setUseSourceNoDataValue()

void QgsRasterDataProvider::setUseSourceNoDataValue	(	int	bandNo,
		bool	use
	)

virtual

Sets the source nodata value usage.

Definition at line 36 of file qgsrasterdataprovider.cpp.

◆ setZoomedInResamplingMethod()

virtual bool QgsRasterDataProvider::setZoomedInResamplingMethod ( ResamplingMethod method )

inlinevirtual

Set resampling method to apply for zoomed-in operations.

Returns: true if success

Since: QGIS 3.16

Definition at line 695 of file qgsrasterdataprovider.h.

◆ setZoomedOutResamplingMethod()

virtual bool QgsRasterDataProvider::setZoomedOutResamplingMethod ( ResamplingMethod method )

inlinevirtual

Set resampling method to apply for zoomed-out operations.

Returns: true if success

Since: QGIS 3.16

Definition at line 709 of file qgsrasterdataprovider.h.

◆ sourceDataType()

Qgis::DataType QgsRasterDataProvider::sourceDataType ( int bandNo ) const

overridepure virtual

Returns source data type for the band specified by number, source data type may be shorter than dataType.

Reimplemented from QgsRasterInterface.

◆ sourceHasNoDataValue()

virtual bool QgsRasterDataProvider::sourceHasNoDataValue ( int bandNo ) const

inlinevirtual

Returns true if source band has no data value.

Definition at line 225 of file qgsrasterdataprovider.h.

◆ sourceNoDataValue()

virtual double QgsRasterDataProvider::sourceNoDataValue ( int bandNo ) const

inlinevirtual

Value representing no data value.

Definition at line 234 of file qgsrasterdataprovider.h.

◆ statusChanged

void QgsRasterDataProvider::statusChanged ( const QString & ) const

signal

Emit a message to be displayed on status bar, usually used by network providers (WMS,WCS)

◆ stepHeight()

virtual int QgsRasterDataProvider::stepHeight ( ) const

inlinevirtual

Step height for raster iterations.

See also: stepWidth()

Definition at line 606 of file qgsrasterdataprovider.h.

◆ stepWidth()

virtual int QgsRasterDataProvider::stepWidth ( ) const

inlinevirtual

Step width for raster iterations.

See also: stepHeight()

Definition at line 600 of file qgsrasterdataprovider.h.

◆ subLayers()

QStringList QgsRasterDataProvider::subLayers ( ) const

inlineoverridevirtual

Returns the sublayers of this layer - useful for providers that manage their own layers, such as WMS.

Reimplemented from QgsDataProvider.

Definition at line 248 of file qgsrasterdataprovider.h.

◆ supportsLegendGraphic()

virtual bool QgsRasterDataProvider::supportsLegendGraphic ( ) const

inlinevirtual

Returns whether the provider supplies a legend graphic.

Definition at line 259 of file qgsrasterdataprovider.h.

◆ temporalCapabilities() [1/2]

const QgsRasterDataProviderTemporalCapabilities * QgsRasterDataProvider::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 432 of file qgsrasterdataprovider.cpp.

◆ temporalCapabilities() [2/2]

QgsRasterDataProviderTemporalCapabilities * QgsRasterDataProvider::temporalCapabilities ( )

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 425 of file qgsrasterdataprovider.cpp.

◆ timestamp()

QDateTime QgsRasterDataProvider::timestamp ( ) const

inlineoverridevirtual

Time stamp of data source in the moment when data/metadata were loaded by provider.

Reimplemented from QgsDataProvider.

Definition at line 435 of file qgsrasterdataprovider.h.

◆ transformCoordinates()

QgsPoint QgsRasterDataProvider::transformCoordinates	(	const QgsPoint &	point,
		QgsRasterDataProvider::TransformType	type
	)

virtual

Transforms coordinates between source image coordinate space [0..width]x[0..height] and layer coordinate space (georeferenced coordinates).

Often this transformation is a simple 2D affine transformation (offset and scaling), but rasters with different georeferencing methods like GCPs (ground control points) or RPCs (rational polynomial coefficients) may require a more complex transform.

If the transform fails (input coordinates are outside of the valid range or data provider does not support this functionality), an empty point is returned.

Since: QGIS 3.14

Definition at line 558 of file qgsrasterdataprovider.cpp.

◆ userNoDataValues()

virtual QgsRasterRangeList QgsRasterDataProvider::userNoDataValues ( int bandNo ) const

inlinevirtual

Returns a list of user no data value ranges.

Definition at line 239 of file qgsrasterdataprovider.h.

◆ userNoDataValuesContains()

bool QgsRasterDataProvider::userNoDataValuesContains	(	int	bandNo,
		double	value
	)		const

protected

Returns true if user no data contains value.

Definition at line 567 of file qgsrasterdataprovider.cpp.

◆ useSourceNoDataValue()

virtual bool QgsRasterDataProvider::useSourceNoDataValue ( int bandNo ) const

inlinevirtual

Returns the source nodata value usage.

Definition at line 228 of file qgsrasterdataprovider.h.

◆ validateCreationOptions()

virtual QString QgsRasterDataProvider::validateCreationOptions	(	const QStringList &	createOptions,
		const QString &	format
	)

inlinevirtual

Validates creation options for a specific dataset and destination format.

Note: used by GDAL provider only; see also validateCreationOptionsFormat() in gdal provider for validating options based on format only

Definition at line 561 of file qgsrasterdataprovider.h.

◆ validatePyramidsConfigOptions()

virtual QString QgsRasterDataProvider::validatePyramidsConfigOptions	(	Qgis::RasterPyramidFormat	pyramidsFormat,
		const QStringList &	configOptions,
		const QString &	fileFormat
	)

inlinevirtual

Validates pyramid creation options for a specific dataset and destination format.

Note: used by GDAL provider only

Definition at line 568 of file qgsrasterdataprovider.h.

◆ write()

virtual bool QgsRasterDataProvider::write	(	const void *	data,
		int	band,
		int	width,
		int	height,
		int	xOffset,
		int	yOffset
	)

inlinevirtual

Writes into the provider datasource.

Definition at line 461 of file qgsrasterdataprovider.h.

◆ writeBlock()

bool QgsRasterDataProvider::writeBlock	(	QgsRasterBlock *	block,
		int	band,
		int	xOffset = `0`,
		int	yOffset = `0`
	)

Writes pixel data from a raster block into the provider data source.

This will override previously stored pixel values. It is assumed that cells in the passed raster block are aligned with the cells of the data source. If raster block does not cover the whole area of the data source, only a subset of pixels covered by the raster block will be overwritten. By default, writing of raster data starts from the first cell of the raster - it is possible to set offset in pixels by specifying non-zero xOffset and yOffset values.

Writing is supported only by some data providers. Provider has to be in editing mode in order to allow write operations.

See also: isEditable(), setEditable()

Returns: true on success

Definition at line 364 of file qgsrasterdataprovider.cpp.

◆ writeFileBasedAttributeTable()

bool QgsRasterDataProvider::writeFileBasedAttributeTable	(	int	bandNumber,
		const QString &	path,
		QString *	errorMessage = `nullptr`
	)		const

Writes the filesystem-based attribute table for the specified bandNumber to path, optionally reporting any error in errorMessage, returns true on success.

Returns: true on success

Note: No checks for Raster Attribute Table validity are performed when saving, it is client code responsibility to handle validation.

Since: QGIS 3.30

Definition at line 738 of file qgsrasterdataprovider.cpp.

◆ writeNativeAttributeTable()

bool QgsRasterDataProvider::writeNativeAttributeTable ( QString * errorMessage = nullptr )

virtual

Writes the native attribute table, optionally reporting any error in errorMessage, returns true on success.

The default implementation does nothing and returns false. Data providers that have NativeRasterAttributeTable provider capability will try to save the native attribute table.

Returns: true on success

Note: No checks for Raster Attribute Table validity are performed when saving, it is client code responsibility to handle validation.

Since: QGIS 3.30

Definition at line 788 of file qgsrasterdataprovider.cpp.

◆ writeXml()

void QgsRasterDataProvider::writeXml	(	QDomDocument &	doc,
		QDomElement &	parentElem
	)		const

overridevirtual

Write base class members to xml.

Reimplemented from QgsRasterInterface.

Definition at line 677 of file qgsrasterdataprovider.cpp.

◆ zoomedInResamplingMethod()

ResamplingMethod QgsRasterDataProvider::zoomedInResamplingMethod ( ) const

inline

Returns resampling method for zoomed-in operations.

Since: QGIS 3.16

Definition at line 701 of file qgsrasterdataprovider.h.

◆ zoomedOutResamplingMethod()

ResamplingMethod QgsRasterDataProvider::zoomedOutResamplingMethod ( ) const

inline

Returns resampling method for zoomed-out operations.

Since: QGIS 3.16

Definition at line 715 of file qgsrasterdataprovider.h.

Member Data Documentation

◆ mDpi

int QgsRasterDataProvider::mDpi = -1

protected

Dots per inch.

Extended WMS (e.g. QGIS mapserver) support DPI dependent output and therefore are suited for printing. A value of -1 means it has not been set

Definition at line 844 of file qgsrasterdataprovider.h.

◆ mExtent

QgsRectangle QgsRasterDataProvider::mExtent

mutableprotected

Definition at line 871 of file qgsrasterdataprovider.h.

◆ mMaxOversampling

double QgsRasterDataProvider::mMaxOversampling = 2.0

protected

Maximum boundary for oversampling (to avoid too much data traffic). Default: 2.0.

Definition at line 883 of file qgsrasterdataprovider.h.

◆ mProviderResamplingEnabled

bool QgsRasterDataProvider::mProviderResamplingEnabled = false

protected

Whether provider resampling is enabled.

Definition at line 874 of file qgsrasterdataprovider.h.

◆ mSrcHasNoDataValue

QList<bool> QgsRasterDataProvider::mSrcHasNoDataValue

protected

Source no data value exists.

Definition at line 856 of file qgsrasterdataprovider.h.

◆ mSrcNoDataValue

QList<double> QgsRasterDataProvider::mSrcNoDataValue

protected

Source no data value is available and is set to be used or internal no data is available.

Used internally only

Cell value representing original source no data. e.g. -9999, indexed from 0

Definition at line 853 of file qgsrasterdataprovider.h.

◆ mUserNoDataValue

QList< QgsRasterRangeList > QgsRasterDataProvider::mUserNoDataValue

protected

List of lists of user defined additional no data values for each band, indexed from 0.

Definition at line 869 of file qgsrasterdataprovider.h.

◆ mUseSrcNoDataValue

QList<bool> QgsRasterDataProvider::mUseSrcNoDataValue

protected

Use source nodata value.

User can disable usage of source nodata value as nodata. It may happen that a value is wrongly given by GDAL as nodata (e.g. 0) and it has to be treated as regular value.

Definition at line 863 of file qgsrasterdataprovider.h.

◆ mZoomedInResamplingMethod

ResamplingMethod QgsRasterDataProvider::mZoomedInResamplingMethod = ResamplingMethod::Nearest

protected

Resampling method for zoomed in pixel extraction.

Definition at line 877 of file qgsrasterdataprovider.h.

◆ mZoomedOutResamplingMethod

ResamplingMethod QgsRasterDataProvider::mZoomedOutResamplingMethod = ResamplingMethod::Nearest

protected

Resampling method for zoomed out pixel extraction.

Definition at line 880 of file qgsrasterdataprovider.h.

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

/home/fischer/src/qgis-3.38/src/core/raster/qgsrasterdataprovider.h
/home/fischer/src/qgis-3.38/src/core/raster/qgsrasterdataprovider.cpp

Classes

Public Types

Signals

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Member Enumeration Documentation

◆ ResamplingMethod

◆ TransformType

Constructor & Destructor Documentation

◆ QgsRasterDataProvider() [1/2]

◆ QgsRasterDataProvider() [2/2]

Member Function Documentation

◆ attributeTable()

◆ bandDescription()

◆ bandOffset()

◆ bandScale()

◆ block()

◆ buildPyramidList()

◆ buildPyramids()

◆ clone()

◆ colorInterpretation()

◆ colorInterpretationName()

◆ colorName()

◆ colorTable()

◆ copyBaseSettings()

◆ create()

◆ dataTimestamp()

◆ dataType()

◆ decodeVirtualRasterProviderUri()

◆ dpi()

◆ elevationProperties() [1/2]

◆ elevationProperties() [2/2]

◆ enableProviderResampling()

◆ encodeVirtualRasterProviderUri()

◆ extent()

◆ fields()

◆ getLegendGraphic()

◆ getLegendGraphicFetcher()

◆ hasPyramids()

◆ identify()

◆ identifyFormatFromName()

◆ identifyFormatLabel()

◆ identifyFormatName()

◆ identifyFormatToCapability()

◆ ignoreExtents()

◆ isEditable()

◆ isProviderResamplingEnabled()

◆ lastError()

◆ lastErrorFormat()

◆ lastErrorTitle()

◆ maxOversampling()

◆ nativeResolutions()

◆ providerCapabilities()

◆ pyramidResamplingMethods()

◆ readBlock() [1/2]

◆ readBlock() [2/2]

◆ readFileBasedAttributeTable()

◆ readNativeAttributeTable()

◆ readXml()

◆ reload()

◆ remove()

◆ removeAttributeTable()

◆ sample()

◆ setAttributeTable()

◆ setDpi()

◆ setEditable()

◆ setInput()

◆ setMaxOversampling()

◆ setNoDataValue()

◆ setUserNoDataValue()

◆ setUseSourceNoDataValue()

◆ setZoomedInResamplingMethod()

◆ setZoomedOutResamplingMethod()

◆ sourceDataType()

◆ sourceHasNoDataValue()

◆ sourceNoDataValue()

◆ statusChanged