/** * \brief Handles asynchronous download of images * * \note added in 2.8 */ class QgsImageFetcher : QObject { %TypeHeaderCode #include %End public: /** Constructor */ QgsImageFetcher( QObject* parent = 0 ); /** Destructor */ virtual ~QgsImageFetcher(); /** Starts the image download * @note Make sure to connect to "finish" and "error" before starting */ virtual void start() = 0; signals: /** Emitted when the download completes * @param legend The downloaded legend image */ void finish( const QImage& legend ); /** Emitted to report progress */ void progress( qint64 received, qint64 total ); /** Emitted when an error occurs */ void error( const QString& msg ); }; /** \ingroup core * Base class for raster data providers. */ class QgsRasterDataProvider : QgsDataProvider, QgsRasterInterface { %TypeHeaderCode #include #include #include %End public: QgsRasterDataProvider(); QgsRasterDataProvider( const QString & uri ); virtual ~QgsRasterDataProvider(); virtual QgsRasterInterface * clone() const = 0; /* It makes no sense to set input on provider */ bool setInput( QgsRasterInterface* input ); /** \brief Renders the layer as an image * \note When render caching (/qgis/enable_render_caching) is on the wms * provider doesn't wait for the reply of the getmap request or all * tiles replies and can return incomplete images. * Temporarily disable render caching if you require the complete * wms image in the first call. */ virtual QImage* draw( const QgsRectangle & viewExtent, int pixelWidth, int pixelHeight ) = 0; /** Get the extent of the data source. * @return QgsRectangle containing the extent of the layer */ virtual QgsRectangle extent() = 0; /** Returns data type for the band specified by number */ virtual QGis::DataType dataType( int bandNo ) const = 0; /** Returns source data type for the band specified by number, * source data type may be shorter than dataType */ virtual QGis::DataType srcDataType( int bandNo ) const = 0; /** Returns data type for the band specified by number */ virtual int colorInterpretation( int theBandNo ) const; QString colorName( int colorInterpretation ) const; /** Reload data (data could change) */ virtual bool reload(); virtual QString colorInterpretationName( int theBandNo ) const; /** Read band scale for raster value * @note added in 2.3 */ virtual double bandScale( int bandNo ) const; /** Read band offset for raster value * @note added in 2.3 */ virtual double bandOffset( int bandNo ) const; /** Get block size */ virtual int xBlockSize() const; virtual int yBlockSize() const; /** Get raster size */ virtual int xSize() const; virtual int ySize() const; /** Read block of data using given extent and size. */ virtual QgsRasterBlock *block( int theBandNo, const QgsRectangle &theExtent, int theWidth, int theHeight ) / Factory /; /** Return true if source band has no data value */ virtual bool srcHasNoDataValue( int bandNo ) const; /** \brief Get source nodata value usage */ virtual bool useSrcNoDataValue( int bandNo ) const; /** \brief Set source nodata value usage */ virtual void setUseSrcNoDataValue( int bandNo, bool use ); /** Value representing no data value. */ virtual double srcNoDataValue( int bandNo ) const; virtual void setUserNoDataValue( int bandNo, const QgsRasterRangeList& noData ); /** Get list of user no data value ranges */ virtual QgsRasterRangeList userNoDataValues( int bandNo ) const; virtual QList colorTable( int bandNo ) const; /** \brief Returns the sublayers of this layer - useful for providers that manage * their own layers, such as WMS */ virtual QStringList subLayers() const; /** \brief Returns whether the provider supplies a legend graphic */ virtual bool supportsLegendGraphic() const; /** \brief Returns the legend rendered as pixmap * * useful for that layer that need to get legend layer remotely as WMS * \param scale Optional parameter that is the Scale of the layer * \param forceRefresh Optional bool parameter to force refresh getLegendGraphic call * \param visibleExtent Visible extent for providers supporting contextual legends, in layer CRS * \note visibleExtent parameter added in 2.8 (no available in python bindings) */ virtual QImage getLegendGraphic( double scale = 0, bool forceRefresh = false, const QgsRectangle * visibleExtent = 0 ); /** * \brief Get an image downloader for the raster legend * * \param mapSettings map settings for legend providers supporting * contextual legends. * * \return a download handler or null if the provider does not support * legend at all. Ownership of the returned object is transferred * to caller. * * \note added in 2.8 * */ virtual QgsImageFetcher* getLegendGraphicFetcher( const QgsMapSettings* mapSettings ) /Factory/; /** \brief Create pyramid overviews */ virtual QString buildPyramids( const QList & thePyramidList, const QString & theResamplingMethod = "NEAREST", QgsRaster::RasterPyramidsFormat theFormat = QgsRaster::PyramidsGTiff, const QStringList & theConfigOptions = QStringList() ); /** \brief Accessor for ths raster layers pyramid list. * @param overviewList used to construct the pyramid list (optional), when empty the list is defined by the provider. * A pyramid list defines the * POTENTIAL pyramids that can be in a raster. To know which of the pyramid layers * ACTUALLY exists you need to look at the existsFlag member in each struct stored in the * list. */ virtual QList buildPyramidList( QList overviewList = QList() ); /** \brief Returns true if raster has at least one populated histogram. */ bool hasPyramids(); /** * Get metadata in a format suitable for feeding directly * into a subset of the GUI raster properties "Metadata" tab. */ virtual QString metadata() = 0; /** \brief Identify raster value(s) found on the point position. The context * parameters theExtent, theWidth and theHeight 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. * * \note The arbitraryness of the returned document is enforced by WMS standards * up to at least v1.3.0 * @param thePoint coordinates in data source CRS * @param theFormat result format * @param theExtent context extent * @param theWidth context width * @param theHeight context height * @param theDpi context dpi * @return QgsRaster::IdentifyFormatValue: map of values for each band, keys are band numbers * (from 1). * QgsRaster::IdentifyFormatFeature: map of QgsRasterFeatureList for each sublayer * (WMS) - TODO: it is not consistent with QgsRaster::IdentifyFormatValue. * QgsRaster::IdentifyFormatHtml: map of HTML strings for each sublayer (WMS). * Empty if failed or there are no results (TODO: better error reporting). */ //virtual QMap identify( const QgsPoint & thePoint, QgsRaster::IdentifyFormat theFormat, const QgsRectangle &theExtent = QgsRectangle(), int theWidth = 0, int theHeight = 0 ); virtual QgsRasterIdentifyResult identify( const QgsPoint & thePoint, QgsRaster::IdentifyFormat theFormat, const QgsRectangle &theExtent = QgsRectangle(), int theWidth = 0, int theHeight = 0, int theDpi = 96 ); /** * \brief 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. * */ virtual QString lastErrorTitle() = 0; /** * \brief 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. * */ virtual QString lastError() = 0; /** Returns the format of the error text for the last error in this provider */ virtual QString lastErrorFormat(); /** Returns the dpi of the output device. */ int dpi() const; /** Sets the output device resolution. */ void setDpi( int dpi ); /** Time stamp of data source in the moment when data/metadata were loaded by provider */ virtual QDateTime timestamp() const; /** Current time stamp of data source */ virtual QDateTime dataTimestamp() const; /** Writes into the provider datasource*/ // TODO: add data type (may be defferent from band type) virtual bool write( void* data, int band, int width, int height, int xOffset, int yOffset ); /** Creates a new dataset with mDataSourceURI */ 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() ); /** Set no data value on created dataset * @param bandNo band number * @param noDataValue no data value */ virtual bool setNoDataValue( int bandNo, double noDataValue ); /** Remove dataset*/ virtual bool remove(); /** Returns a list of pyramid resampling method name and label pairs * for given provider */ static QList > pyramidResamplingMethods( const QString& providerKey ); /** Validates creation options for a specific dataset and destination format. * @note used by GDAL provider only * @note see also validateCreationOptionsFormat() in gdal provider for validating options based on format only */ virtual QString validateCreationOptions( const QStringList& createOptions, const QString& format ); /** Validates pyramid creation options for a specific dataset and destination format * @note used by GDAL provider only */ virtual QString validatePyramidsConfigOptions( QgsRaster::RasterPyramidsFormat pyramidsFormat, const QStringList & theConfigOptions, const QString & fileFormat ); static QString identifyFormatName( QgsRaster::IdentifyFormat format ); static QgsRaster::IdentifyFormat identifyFormatFromName( const QString& formatName ); static QString identifyFormatLabel( QgsRaster::IdentifyFormat format ); static Capability identifyFormatToCapability( QgsRaster::IdentifyFormat format ); signals: /** Emit a signal to notify of the progress event. * Emitted theProgress is in percents (0.0-100.0) */ void progress( int theType, double theProgress, const QString& theMessage ); void progressUpdate( int theProgress ); /** Emit a message to be displayed on status bar, usually used by network providers (WMS,WCS) * @note added in 2.14 */ void statusChanged( const QString& ); protected: /** Read block of data * @note not available in python bindings */ virtual void readBlock( int bandNo, int xBlock, int yBlock, void *data ); /** Read block of data using give extent and size * @note not available in python bindings */ //virtual void readBlock( int bandNo, QgsRectangle const & viewExtent, int width, int height, void *data ); /** Returns true if user no data contains value */ bool userNoDataValuesContains( int bandNo, double value ) const; /** Copy member variables from other raster data provider. Useful for implementation of clone() method in subclasses */ void copyBaseSettings( const QgsRasterDataProvider& other ); //! @note not available in Python bindings //static QStringList cStringList2Q_( char ** stringList ); static QString makeTableCell( const QString & value ); static QString makeTableCells( const QStringList & values ); /** Source no data value is available and is set to be used or internal no data * is available. Used internally only */ //bool hasNoDataValue ( int theBandNo ); };