QGIS API Documentation  2.2.0-Valmiera
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Properties Friends Macros Groups Pages
Public Types | Public Slots | Signals | Public Member Functions | Static Public Member Functions | Static Public Attributes | Protected Member Functions | Private Member Functions | Private Attributes | List of all members
QgsRasterLayer Class Reference

This class provides qgis with the ability to render raster datasets onto the mapcanvas. More...

#include <qgsrasterlayer.h>

Inheritance diagram for QgsRasterLayer:
Inheritance graph
[legend]
Collaboration diagram for QgsRasterLayer:
Collaboration graph
[legend]

Public Types

enum  ColorShadingAlgorithm {
  UndefinedShader, PseudoColorShader, FreakOutShader, ColorRampShader,
  UserDefinedShader
}
 This enumerator describes the types of shading that can be used. More...
enum  LayerType { GrayOrUndefined, Palette, Multiband, ColorLayer }
 This enumerator describes the type of raster layer. More...
- Public Types inherited from QgsMapLayer
enum  LayerType { VectorLayer, RasterLayer, PluginLayer }
 Layers enum defining the types of layers that can be added to a map. More...

Public Slots

void showStatusMessage (const QString &theMessage)
void updateProgress (int, int)
 Propagate progress updates from GDAL up to the parent app.
void onProgress (int, double, QString)
 receive progress signal from provider
- Public Slots inherited from QgsMapLayer
virtual void invalidTransformInput ()
 Event handler for when a coordinate transform fails due to bad vertex error.
void setMinimumScale (float theMinScale)
 Accessor and mutator for the minimum scale denominator member.
float minimumScale () const
void setMaximumScale (float theMaxScale)
 Accessor and mutator for the maximum scale denominator member.
float maximumScale () const
void toggleScaleBasedVisibility (bool theVisibilityFlag)
 Accessor and mutator for the scale based visilibility flag.
bool hasScaleBasedVisibility () const
void clearCacheImage ()
 Clear cached image added in 1.5.

Signals

void progressUpdate (int theValue)
 Signal for notifying listeners of long running processes.
void dataChanged ()
 This is emitted whenever data or metadata (e.g.
void rendererChanged ()
 Signal emitted when the symbology changes, through call to setRenderer()
- Signals inherited from QgsMapLayer
void drawingProgress (int theProgress, int theTotalSteps)
 Emit a signal to notify of a progress event.
void statusChanged (QString theStatus)
 Emit a signal with status (e.g.
void layerNameChanged ()
 Emit a signal that the layer name has been changed.
void layerCrsChanged ()
 Emit a signal that layer's CRS has been reset added in 1.4.
void repaintRequested ()
 This signal should be connected with the slot QgsMapCanvas::refresh()
void screenUpdateRequested ()
 The layer emits this signal when a screen update is requested.
void recalculateExtents ()
 This is used to send a request that any mapcanvas using this layer update its extents.
void dataChanged ()
 data of layer changed added in 1.5
void blendModeChanged (const QPainter::CompositionMode &blendMode)
 Signal emitted when the blend mode is changed, through QgsMapLayer::setBlendMode()

Public Member Functions

 QgsRasterLayer ()
 Constructor.
 QgsRasterLayer (const QString &path, const QString &baseName=QString::null, bool loadDefaultStyleFlag=true)
 This is the constructor for the RasterLayer class.
 QgsRasterLayer (const QString &uri, const QString &baseName, const QString &providerKey, bool loadDefaultStyleFlag=true)
 [ data provider interface ] Constructor in provider mode
 ~QgsRasterLayer ()
 The destructor.
void setDataProvider (const QString &provider)
 [ data provider interface ] Set the data provider
LayerType rasterType ()
 Accessor for raster layer type (which is a read only property)
void setRenderer (QgsRasterRenderer *theRenderer)
 Set raster renderer.
QgsRasterRendererrenderer () const
QgsRasterResampleFilterresampleFilter () const
 Set raster resample filter.
QgsBrightnessContrastFilterbrightnessFilter () const
QgsHueSaturationFilterhueSaturationFilter () const
QgsRasterPipepipe ()
 Get raster pipe.
int width () const
 Accessor that returns the width of the (unclipped) raster.
int height () const
 Accessor that returns the height of the (unclipped) raster.
int bandCount () const
 Get the number of bands in this layer.
const QString bandName (int theBandNoInt)
 Get the name of a band given its number.
QgsRasterDataProviderdataProvider ()
 Returns the data provider.
const QgsRasterDataProviderdataProvider () const
 Returns the data provider in a const-correct manner.
virtual void reload ()
 Synchronises with changes in the datasource.
bool draw (QgsRenderContext &rendererContext)
 This is called when the view on the raster layer needs to be redrawn.
void draw (QPainter *theQPainter, QgsRasterViewPort *myRasterViewPort, const QgsMapToPixel *theQgsMapToPixel=0)
 This is an overloaded version of the draw() function that is called by both draw() and thumbnailAsPixmap.
QString lastError ()
 [ data provider interface ] If an operation returns 0 (e.g.
QString lastErrorTitle ()
 [ data provider interface ] If an operation returns 0 (e.g.
QList< QPair< QString, QColor > > legendSymbologyItems () const
 Returns a list with classification items (Text and color)
QString metadata ()
 Obtain GDAL Metadata for this layer.
QPixmap paletteAsPixmap (int theBandNumber=1)
 Get an 100x100 pixmap of the color palette.
QString providerType () const
 [ data provider interface ] Which provider is being used for this Raster Layer?
double rasterUnitsPerPixelX ()
 Returns the number of raster units per each raster pixel.
double rasterUnitsPerPixelY ()
void setContrastEnhancement (QgsContrastEnhancement::ContrastEnhancementAlgorithm theAlgorithm, QgsRaster::ContrastEnhancementLimits theLimits=QgsRaster::ContrastEnhancementMinMax, QgsRectangle theExtent=QgsRectangle(), int theSampleSize=SAMPLE_SIZE, bool theGenerateLookupTableFlag=true)
 Set contrast enhancement algorithm.
void setDefaultContrastEnhancement ()
 Set default contrast enhancement.
void setDrawingStyle (const QString &theDrawingStyleQString)
 Overloaded version of the above function for convenience when restoring from xml.
void showProgress (int theValue)
 [ data provider interface ] A wrapper function to emit a progress update signal
virtual QStringList subLayers () const
 Returns the sublayers of this layer - Useful for providers that manage their own layers, such as WMS.
QPixmap previewAsPixmap (QSize size, QColor bgColor=Qt::white)
 Draws a preview of the rasterlayer into a pixmap.
void triggerRepaint ()
 Emit a signal asking for a repaint.
virtual void setLayerOrder (const QStringList &layers)
 Reorders the previously selected sublayers of this layer from bottom to top.
virtual void setSubLayerVisibility (QString name, bool vis)
 Set the visibility of the given sublayer name.
virtual QDateTime timestamp () const
 Time stamp of data source in the moment when data/metadata were loaded by provider.
- Public Member Functions inherited from QgsMapLayer
 QgsMapLayer (QgsMapLayer::LayerType type=VectorLayer, QString lyrname=QString::null, QString source=QString::null)
 Constructor.
virtual ~QgsMapLayer ()
 Destructor.
QgsMapLayer::LayerType type () const
 Get the type of the layer.
QString id () const
 Get this layer's unique ID, this ID is used to access this layer from map layer registry.
void setLayerName (const QString &name)
 Set the display name of the layer.
const QString & name () const
 Get the display name of the layer.
const QString & originalName () const
 Get the original name of the layer.
void setTitle (const QString &title)
const QString & title () const
void setAbstract (const QString &abstract)
const QString & abstract () const
void setKeywordList (const QString &keywords)
const QString & keywordList () const
void setDataUrl (const QString &dataUrl)
const QString & dataUrl () const
void setDataUrlFormat (const QString &dataUrlFormat)
const QString & dataUrlFormat () const
void setAttribution (const QString &attrib)
const QString & attribution () const
void setAttributionUrl (const QString &attribUrl)
const QString & attributionUrl () const
void setMetadataUrl (const QString &metaUrl)
const QString & metadataUrl () const
void setMetadataUrlType (const QString &metaUrlType)
const QString & metadataUrlType () const
void setMetadataUrlFormat (const QString &metaUrlFormat)
const QString & metadataUrlFormat () const
void setBlendMode (const QPainter::CompositionMode &blendMode)
 Write blend mode for layer.
QPainter::CompositionMode blendMode () const
 Read blend mode for layer.
virtual void drawLabels (QgsRenderContext &rendererContext)
 Draw labels.
virtual QgsRectangle extent ()
 Return the extent of the layer.
bool isValid ()
QString publicSource () const
const QString & source () const
 Returns the source for the layer.
virtual bool isEditable () const
 True if the layer can be edited.
bool readLayerXML (const QDomElement &layerElement)
 sets state from Dom document
bool writeLayerXML (QDomElement &layerElement, QDomDocument &document)
 stores state in Dom node
void setCustomProperty (const QString &key, const QVariant &value)
 Set a custom property for layer.
QVariant customProperty (const QString &value, const QVariant &defaultValue=QVariant()) const
 Read a custom property from layer.
void removeCustomProperty (const QString &key)
 Remove a custom property from layer.
virtual QgsError error () const
 Get current status error.
const
QgsCoordinateReferenceSystem
crs () const
 Returns layer's spatial reference system.
void setCrs (const QgsCoordinateReferenceSystem &srs, bool emitSignal=true)
 Sets layer's spatial reference system.
virtual QString styleURI ()
 Retrieve the style URI for this layer (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)
virtual QString loadDefaultStyle (bool &theResultFlag)
 Retrieve the default style for this layer if one exists (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)
virtual QString loadNamedStyle (const QString &theURI, bool &theResultFlag)
 Retrieve a named style for this layer if one exists (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)
virtual bool loadNamedStyleFromDb (const QString &db, const QString &theURI, QString &qml)
virtual void exportNamedStyle (QDomDocument &doc, QString &errorMsg)
 Export the properties of this layer as named style in a QDomDocument.
virtual void exportSldStyle (QDomDocument &doc, QString &errorMsg)
 Export the properties of this layer as SLD style in a QDomDocument.
virtual QString saveDefaultStyle (bool &theResultFlag)
 Save the properties of this layer as the default style (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)
virtual QString saveNamedStyle (const QString &theURI, bool &theResultFlag)
 Save the properties of this layer as a named style (either as a .qml file on disk or as a record in the users style table in their personal qgis.db)
virtual QString saveSldStyle (const QString &theURI, bool &theResultFlag)
virtual QString loadSldStyle (const QString &theURI, bool &theResultFlag)
virtual bool readSld (const QDomNode &node, QString &errorMessage)
QUndoStack * undoStack ()
 Return pointer to layer's undo stack.
QImage * cacheImage ()
 Get the QImage used for caching render operations.
void setCacheImage (QImage *thepImage)
 Set the QImage used for caching render operations.
virtual void onCacheImageDelete ()
 Is called when the cache image is being deleted.

Static Public Member Functions

static bool isValidRasterFileName (const QString &theFileNameQString, QString &retError)
 This helper checks to see whether the file name appears to be a valid raster file name.
static bool isValidRasterFileName (const QString &theFileNameQString)
static QDateTime lastModified (const QString &name)
 Return time stamp for given file name.
- Static Public Member Functions inherited from QgsMapLayer
static QString capitaliseLayerName (const QString &name)
 A convenience function to (un)capitalise the layer name.

Static Public Attributes

static const double CUMULATIVE_CUT_LOWER = 0.02
 Default cumulative cut lower limit.
static const double CUMULATIVE_CUT_UPPER = 0.98
 Default cumulative cut upper limit.
static const double SAMPLE_SIZE = 250000
 Default sample size (number of pixels) for estimated statistics/histogram calculation.

Protected Member Functions

bool readSymbology (const QDomNode &node, QString &errorMessage)
 Read the symbology for the current layer from the Dom node supplied.
bool readXml (const QDomNode &layer_node)
 Reads layer specific state from project file Dom node.
bool writeSymbology (QDomNode &, QDomDocument &doc, QString &errorMessage) const
 Write the symbology for the layer into the docment provided.
bool writeXml (QDomNode &layer_node, QDomDocument &doc)
 Write layer specific state to project file Dom node.
- Protected Member Functions inherited from QgsMapLayer
virtual void setExtent (const QgsRectangle &rect)
 Set the extent.
void setValid (bool valid)
 set whether layer is valid or not - should be used in constructor.
void readCustomProperties (const QDomNode &layerNode, const QString &keyStartsWith="")
 Read custom properties from project file.
void writeCustomProperties (QDomNode &layerNode, QDomDocument &doc) const
 Write custom properties to project file.
void connectNotify (const char *signal)
 debugging member - invoked when a connect() is made to this object
void appendError (const QgsErrorMessage &theMessage)
 Add error message.
void setError (const QgsError &theError)
 Set error message.

Private Member Functions

void init ()
 Initialize default values.
void closeDataProvider ()
 Close data provider and clear related members.
bool update ()
 Update the layer if it is outdated.
void setRendererForDrawingStyle (const QgsRaster::DrawingStyle &theDrawingStyle)
 Sets corresponding renderer for style.

Private Attributes

const QString QSTRING_NOT_SET
 Constant defining flag for XML and a constant that signals property not used.
const QString TRSTRING_NOT_SET
QgsRasterDataProvidermDataProvider
 Pointer to data provider.
QString mError
 [ data provider interface ]The error message associated with the last error
QString mErrorCaption
 [ data provider interface ] The error caption associated with the last error
QDateTime mLastModified
 [ data provider interface ] Timestamp, the last modified time of the data source when the layer was created
QgsRasterViewPort mLastViewPort
QString mProviderKey
 [ data provider interface ] Data provider key
LayerType mRasterType
QgsRasterPipe mPipe

Additional Inherited Members

- Protected Attributes inherited from QgsMapLayer
QgsRectangle mExtent
 Extent of the layer.
bool mValid
 Indicates if the layer is valid and can be drawn.
QString mDataSource
 data source description string, varies by layer type
QString mLayerName
 Name of the layer - used for display.
QString mLayerOrigName
 Original name of the layer.
QString mTitle
QString mAbstract
 Description of the layer.
QString mKeywordList
QString mDataUrl
 DataUrl of the layer.
QString mDataUrlFormat
QString mAttribution
 Attribution of the layer.
QString mAttributionUrl
QString mMetadataUrl
 MetadataUrl of the layer.
QString mMetadataUrlType
QString mMetadataUrlFormat
QgsError mError
 Error.

Detailed Description

This class provides qgis with the ability to render raster datasets onto the mapcanvas.

The qgsrasterlayer class makes use of gdal for data io, and thus supports any gdal supported format. The constructor attempts to infer what type of file (LayerType) is being opened - not in terms of the file format (tif, ascii grid etc.) but rather in terms of whether the image is a GRAYSCALE, PaletteD or Multiband,

Within the three allowable raster layer types, there are 8 permutations of how a layer can actually be rendered. These are defined in the DrawingStyle enum and consist of:

SingleBandGray -> a GRAYSCALE layer drawn as a range of gray colors (0-255) SingleBandPseudoColor -> a GRAYSCALE layer drawn using a pseudocolor algorithm PalettedSingleBandGray -> a PaletteD layer drawn in gray scale (using only one of the color components) PalettedSingleBandPseudoColor -> a PaletteD layer having only one of its color components rendered as psuedo color PalettedMultiBandColor -> a PaletteD image where the bands contains 24bit color info and 8 bits is pulled out per color MultiBandSingleBandGray -> a layer containing 2 or more bands, but using only one band to produce a grayscale image MultiBandSingleBandPseudoColor -> a layer containing 2 or more bands, but using only one band to produce a pseudocolor image MultiBandColor -> a layer containing 2 or more bands, mapped to the three RGBcolors. In the case of a multiband with only two bands, one band will have to be mapped to more than one color

Each of the above mentioned drawing styles is implemented in its own draw* function. Some of the drawing styles listed above require statistics about the layer such as the min / max / mean / stddev etc. statistics for a band can be gathered using the bandStatistics function. Note that statistics gathering is a slow process and every effort should be made to call this function as few times as possible. For this reason, qgsraster has a vector class member to store stats for each band. The constructor initialises this vector on startup, but only populates the band name and number fields.

Note that where bands are of gdal 'undefined' type, their values may exceed the renderable range of 0-255. Because of this a linear scaling histogram enhanceContrast is applied to undefined layers to normalise the data into the 0-255 range.

A qgsrasterlayer band can be referred to either by name or by number (base=1). It should be noted that band names as stored in datafiles may not be unique, and so the rasterlayer class appends the band number in brackets behind each band name.

Sample usage of the QgsRasterLayer class:

QString myFileNameQString = "/path/to/file";
QFileInfo myFileInfo(myFileNameQString);
QString myBaseNameQString = myFileInfo.baseName();
QgsRasterLayer *myRasterLayer = new QgsRasterLayer(myFileNameQString, myBaseNameQString);

In order to automate redrawing of a raster layer, you should like it to a map canvas like this :

QObject::connect( myRasterLayer, SIGNAL(repaintRequested()), mapCanvas, SLOT(refresh()) );

A raster layer can also export its legend as a pixmap:

QPixmap myQPixmap = myRasterLayer->legendPixmap();

Once a layer has been created you can find out what type of layer it is (GrayOrUndefined, Palette or Multiband):

if (rasterLayer->rasterType()==QgsRasterLayer::Multiband)
{
//do something
}
else if (rasterLayer->rasterType()==QgsRasterLayer::Palette)
{
//do something
}
else // QgsRasterLayer::GrayOrUndefined
{
//do something.
}

You can combine layer type detection with the setDrawingStyle method to override the default drawing style assigned when a layer is loaded:

if (rasterLayer->rasterType()==QgsRasterLayer::Multiband)
{
myRasterLayer->setDrawingStyle(QgsRasterLayer::MultiBandSingleBandPseudoColor);
}
else if (rasterLayer->rasterType()==QgsRasterLayer::Palette)
{
myRasterLayer->setDrawingStyle(QgsRasterLayer::PalettedSingleBandPseudoColor);
}
else // QgsRasterLayer::GrayOrUndefined
{
myRasterLayer->setDrawingStyle(QgsRasterLayer::SingleBandPseudoColor);
}

Raster layers can also have an arbitrary level of transparency defined, and have their color palettes inverted using the setTransparency and setInvertHistogram methods.

Pseudocolor images can have their output adjusted to a given number of standard deviations using the setStandardDeviations method.

The final area of functionality you may be interested in is band mapping. Band mapping allows you to choose arbitrary band -> color mappings and is applicable only to Palette and Multiband rasters, There are four mappings that can be made: red, green, blue and gray. Mappings are non-exclusive. That is a given band can be assigned to no, some or all color mappings. The constructor sets sensible defaults for band mappings but these can be overridden at run time using the setRedBandName, setGreenBandName, setBlueBandName and setGrayBandName methods.

Definition at line 167 of file qgsrasterlayer.h.

Member Enumeration Documentation

This enumerator describes the types of shading that can be used.

Enumerator:
UndefinedShader 
PseudoColorShader 
FreakOutShader 
ColorRampShader 
UserDefinedShader 

Definition at line 213 of file qgsrasterlayer.h.

This enumerator describes the type of raster layer.

Enumerator:
GrayOrUndefined 
Palette 
Multiband 
ColorLayer 

Definition at line 223 of file qgsrasterlayer.h.

Constructor & Destructor Documentation

QgsRasterLayer::QgsRasterLayer ( )

Constructor.

Provider is not set.

Definition at line 79 of file qgsrasterlayer.cpp.

References init(), and QgsMapLayer::mValid.

QgsRasterLayer::QgsRasterLayer ( const QString &  path,
const QString &  baseName = QString::null,
bool  loadDefaultStyleFlag = true 
)

This is the constructor for the RasterLayer class.

The main tasks carried out by the constructor are:

-Load the rasters default style (.qml) file if it exists

-Populate the RasterStatsVector with initial values for each band.

-Calculate the layer extents

-Determine whether the layer is gray, paletted or multiband.

-Assign sensible defaults for the red, green, blue and gray bands.

Definition at line 89 of file qgsrasterlayer.cpp.

References init(), QgsMapLayer::loadDefaultStyle(), QgsMapLayer::mValid, QgsDebugMsg, setDataProvider(), and setDefaultContrastEnhancement().

QgsRasterLayer::QgsRasterLayer ( const QString &  uri,
const QString &  baseName,
const QString &  providerKey,
bool  loadDefaultStyleFlag = true 
)

[ data provider interface ] Constructor in provider mode

Todo:
Rename into a general constructor when the old raster interface is retired parameter dummy is just there to distinguish this function signature from the old non-provider one.

Definition at line 121 of file qgsrasterlayer.cpp.

References init(), QgsMapLayer::loadDefaultStyle(), QgsMapLayer::mValid, QgsDebugMsg, setDataProvider(), setDefaultContrastEnhancement(), QgsMapLayer::statusChanged(), and tr.

QgsRasterLayer::~QgsRasterLayer ( )

The destructor.

Definition at line 153 of file qgsrasterlayer.cpp.

References QgsMapLayer::mValid.

Member Function Documentation

int QgsRasterLayer::bandCount ( ) const
const QString QgsRasterLayer::bandName ( int  theBandNoInt)

Get the name of a band given its number.

Definition at line 220 of file qgsrasterlayer.cpp.

References dataProvider(), and QgsRasterInterface::generateBandName().

Referenced by metadata(), and QgsRasterHistogramWidget::QgsRasterHistogramWidget().

QgsBrightnessContrastFilter* QgsRasterLayer::brightnessFilter ( ) const
inline

Definition at line 255 of file qgsrasterlayer.h.

Referenced by readSymbology(), and setDataProvider().

void QgsRasterLayer::closeDataProvider ( )
private

Close data provider and clear related members.

Definition at line 981 of file qgsrasterlayer.cpp.

References mDataProvider, mPipe, QgsMapLayer::mValid, and QgsRasterPipe::remove().

Referenced by readXml(), and update().

void QgsRasterLayer::dataChanged ( )
signal

This is emitted whenever data or metadata (e.g.

color table, extent) has changed

Note
added in 1.7

Referenced by update().

QgsRasterDataProvider * QgsRasterLayer::dataProvider ( )
const QgsRasterDataProvider * QgsRasterLayer::dataProvider ( ) const

Returns the data provider in a const-correct manner.

Note
available in python bindings as constDataProvider()
Returns
0 if not using the data provider model (i.e. directly using GDAL)

Definition at line 241 of file qgsrasterlayer.cpp.

References mDataProvider.

bool QgsRasterLayer::draw ( QgsRenderContext rendererContext)
virtual
void QgsRasterLayer::draw ( QPainter *  theQPainter,
QgsRasterViewPort myRasterViewPort,
const QgsMapToPixel theQgsMapToPixel = 0 
)
int QgsRasterLayer::height ( ) const

Accessor that returns the height of the (unclipped) raster.

Definition at line 1631 of file qgsrasterlayer.cpp.

References mDataProvider, and QgsRasterInterface::ySize().

Referenced by draw().

QgsHueSaturationFilter* QgsRasterLayer::hueSaturationFilter ( ) const
inline

Definition at line 256 of file qgsrasterlayer.h.

Referenced by readSymbology(), and setDataProvider().

void QgsRasterLayer::init ( )
private
bool QgsRasterLayer::isValidRasterFileName ( const QString &  theFileNameQString,
QString &  retError 
)
static

This helper checks to see whether the file name appears to be a valid raster file name.

If the file name looks like it could be valid, but some sort of error occurs in processing the file, the error is returned in retError.

Definition at line 168 of file qgsrasterlayer.cpp.

References cast_to_fptr, QgsProviderRegistry::function(), QgsProviderRegistry::instance(), and QgsDebugMsg.

Referenced by isValidRasterFileName().

bool QgsRasterLayer::isValidRasterFileName ( const QString &  theFileNameQString)
static

Definition at line 181 of file qgsrasterlayer.cpp.

References isValidRasterFileName().

QString QgsRasterLayer::lastError ( )
virtual

[ data provider interface ] If an operation returns 0 (e.g.

draw()), this function returns the text of the error associated with the failure

Reimplemented from QgsMapLayer.

Definition at line 441 of file qgsrasterlayer.cpp.

References mError.

QString QgsRasterLayer::lastErrorTitle ( )
virtual

[ data provider interface ] If an operation returns 0 (e.g.

draw()), this function returns the text of the error associated with the failure

Reimplemented from QgsMapLayer.

Definition at line 446 of file qgsrasterlayer.cpp.

References mErrorCaption.

QDateTime QgsRasterLayer::lastModified ( const QString &  name)
static

Return time stamp for given file name.

Definition at line 187 of file qgsrasterlayer.cpp.

References QgsDebugMsg.

Referenced by setDataProvider().

QList< QPair< QString, QColor > > QgsRasterLayer::legendSymbologyItems ( ) const

Returns a list with classification items (Text and color)

Note
this method was added in version 1.8

Definition at line 451 of file qgsrasterlayer.cpp.

References QgsRasterRenderer::legendSymbologyItems(), mPipe, QgsRasterPipe::renderer(), and renderer().

Referenced by QgsLegendModel::addRasterLayerItems(), and QgsLegendModel::updateRasterSymbolItemText().

QString QgsRasterLayer::metadata ( )
virtual
void QgsRasterLayer::onProgress ( int  theType,
double  theProgress,
QString  theMessage 
)
slot

receive progress signal from provider

Definition at line 1290 of file qgsrasterlayer.cpp.

References progressUpdate(), and QgsDebugMsg.

Referenced by setDataProvider().

QPixmap QgsRasterLayer::paletteAsPixmap ( int  theBandNumber = 1)

Get an 100x100 pixmap of the color palette.

If the layer has no palette a white pixmap will be returned

Parameters
theBandNumberthe number of the band to use for generating a pixmap of the associated palette
Returns
a 100x100 pixel QPixmap of the bands palette

Definition at line 678 of file qgsrasterlayer.cpp.

References QgsRasterDataProvider::colorInterpretation(), QgsRasterDataProvider::colorTable(), QgsColorRampShader::DISCRETE, mDataProvider, QgsRaster::PaletteIndex, QgsDebugMsg, QgsColorRampShader::setColorRampItemList(), QgsColorRampShader::setColorRampType(), and QgsColorRampShader::shade().

QgsRasterPipe* QgsRasterLayer::pipe ( )
inline

Get raster pipe.

Definition at line 259 of file qgsrasterlayer.h.

QPixmap QgsRasterLayer::previewAsPixmap ( QSize  size,
QColor  bgColor = Qt::white 
)
void QgsRasterLayer::progressUpdate ( int  theValue)
signal

Signal for notifying listeners of long running processes.

Referenced by onProgress(), and showProgress().

QString QgsRasterLayer::providerType ( ) const

[ data provider interface ] Which provider is being used for this Raster Layer?

Note
added in 2.0

Definition at line 732 of file qgsrasterlayer.cpp.

References mProviderKey.

Referenced by QgsLegendModel::addRasterLayerItems().

LayerType QgsRasterLayer::rasterType ( )
inline

Accessor for raster layer type (which is a read only property)

Definition at line 246 of file qgsrasterlayer.h.

double QgsRasterLayer::rasterUnitsPerPixelX ( )

Returns the number of raster units per each raster pixel.

In a world file, this is normally the first row (without the sign)

Returns
the horizontal units per pixel as reported in the GDAL geotramsform[1]

Definition at line 740 of file qgsrasterlayer.cpp.

References QgsRasterInterface::capabilities(), QgsRasterDataProvider::extent(), mDataProvider, QgsRasterInterface::Size, QgsRectangle::width(), and QgsRasterInterface::xSize().

double QgsRasterLayer::rasterUnitsPerPixelY ( )
bool QgsRasterLayer::readSymbology ( const QDomNode &  node,
QString &  errorMessage 
)
protectedvirtual
bool QgsRasterLayer::readXml ( const QDomNode &  layer_node)
protectedvirtual

Reads layer specific state from project file Dom node.

Raster layer project file XML of form:

Note
Called by QgsMapLayer::readXML().
Note
Make sure to read the file first so stats etc are initialised properly!

Reimplemented from QgsMapLayer.

Definition at line 1401 of file qgsrasterlayer.cpp.

References bandCount(), closeDataProvider(), QgsMapLayer::crs(), QgsDataSourceURI::encodedUri(), init(), mDataProvider, QgsMapLayer::mDataSource, mProviderKey, QgsMapLayer::mValid, QgsDebugMsg, readSymbology(), renderer(), setDataProvider(), QgsDataSourceURI::setEncodedUri(), QgsDataSourceURI::setParam(), setRendererForDrawingStyle(), QgsRasterDataProvider::setUserNoDataValue(), QgsRasterDataProvider::setUseSrcNoDataValue(), QgsRaster::SingleBandColorDataStyle, and QgsMapLayer::type().

void QgsRasterLayer::reload ( )
virtual

Synchronises with changes in the datasource.

Note
added in version 1.6

Reimplemented from QgsMapLayer.

Definition at line 246 of file qgsrasterlayer.cpp.

References mDataProvider, and QgsDataProvider::reloadData().

QgsRasterRenderer* QgsRasterLayer::renderer ( ) const
inline
void QgsRasterLayer::rendererChanged ( )
signal

Signal emitted when the symbology changes, through call to setRenderer()

Referenced by setRenderer().

QgsRasterResampleFilter* QgsRasterLayer::resampleFilter ( ) const
inline

Set raster resample filter.

Takes ownership of the resample filter object

Definition at line 253 of file qgsrasterlayer.h.

Referenced by readSymbology(), and setDataProvider().

void QgsRasterLayer::setContrastEnhancement ( QgsContrastEnhancement::ContrastEnhancementAlgorithm  theAlgorithm,
QgsRaster::ContrastEnhancementLimits  theLimits = QgsRaster::ContrastEnhancementMinMax,
QgsRectangle  theExtent = QgsRectangle(),
int  theSampleSize = SAMPLE_SIZE,
bool  theGenerateLookupTableFlag = true 
)

Set contrast enhancement algorithm.

Parameters
theAlgorithmContrast enhancement algorithm
theLimitsLimits
theExtentExtent used to calculate limits, if empty, use full layer extent
theSampleSizeSize of data sample to calculate limits, if 0, use full resolution
theGenerateLookupTableFlagGenerate llokup table.

Definition at line 988 of file qgsrasterlayer.cpp.

References QgsRasterInterface::bandStatistics(), QgsMultiBandColorRenderer::blueBand(), QgsRaster::ContrastEnhancementCumulativeCut, QgsRaster::ContrastEnhancementMinMax, QgsRaster::ContrastEnhancementStdDev, CUMULATIVE_CUT_LOWER, CUMULATIVE_CUT_UPPER, QgsRasterInterface::cumulativeCut(), QgsRasterDataProvider::dataType(), QgsSingleBandGrayRenderer::grayBand(), QgsMultiBandColorRenderer::greenBand(), QgsRectangle::isEmpty(), QgsRasterBandStats::Max, QgsRasterBandStats::maximumValue, mDataProvider, QgsRasterBandStats::Mean, QgsRasterBandStats::mean, QgsRasterBandStats::Min, QgsRasterBandStats::minimumValue, mPipe, QgsDebugMsg, QgsMultiBandColorRenderer::redBand(), QgsRasterPipe::renderer(), QgsMultiBandColorRenderer::setBlueContrastEnhancement(), QgsSingleBandGrayRenderer::setContrastEnhancement(), QgsContrastEnhancement::setContrastEnhancementAlgorithm(), QgsMultiBandColorRenderer::setGreenContrastEnhancement(), QgsContrastEnhancement::setMaximumValue(), QgsContrastEnhancement::setMinimumValue(), QgsMultiBandColorRenderer::setRedContrastEnhancement(), QgsRasterBandStats::StdDev, QgsRasterBandStats::stdDev, and QgsRasterRenderer::type().

Referenced by setDefaultContrastEnhancement().

void QgsRasterLayer::setDataProvider ( const QString &  provider)

[ data provider interface ] Set the data provider

Definition at line 775 of file qgsrasterlayer.cpp.

References QgsRaster::AlphaBand, QgsMapLayer::appendError(), QGis::ARGB32, QGis::ARGB32_Premultiplied, QgsRasterInterface::bandCount(), brightnessFilter(), QgsRasterInterface::capabilities(), QgsRasterDataProvider::colorInterpretation(), ColorLayer, QgsRasterDataProvider::colorTable(), QgsRaster::ContinuousPalette, QgsDataProvider::crs(), QgsMapLayer::crs(), QgsDataProvider::dataSourceUri(), QgsRasterDataProvider::dataType(), ERR, QgsDataProvider::error(), QgsRasterDataProvider::extent(), GrayOrUndefined, hueSaturationFilter(), QgsRasterInterface::IdentifyFeature, QgsRaster::IdentifyFormatFeature, QgsRaster::IdentifyFormatHtml, QgsRasterDataProvider::identifyFormatName(), QgsRaster::IdentifyFormatText, QgsRaster::IdentifyFormatUndefined, QgsRaster::IdentifyFormatValue, QgsRasterInterface::IdentifyHtml, QgsRasterInterface::IdentifyText, QgsRasterInterface::IdentifyValue, QgsProviderRegistry::instance(), QgsColorRampShader::INTERPOLATED, QgsDataProvider::isValid(), lastModified(), mDataProvider, QgsMapLayer::mDataSource, mLastModified, QgsMapLayer::mLayerName, mPipe, mProviderKey, mRasterType, Multiband, QgsRaster::MultiBandColor, QgsMapLayer::mValid, QgsMapLayer::name(), onProgress(), Palette, QgsRaster::PalettedColor, QgsRaster::PaletteIndex, QgsProviderRegistry::provider(), QgsDebugMsg, QgsRasterPipe::remove(), QgsRasterPipe::renderer(), renderer(), resampleFilter(), QgsRasterPipe::set(), QgsRasterRenderer::setAlphaBand(), QgsColorRampShader::setColorRampItemList(), QgsColorRampShader::setColorRampType(), QgsMapLayer::setCrs(), QgsMapLayer::setCustomProperty(), QgsMapLayer::setError(), QgsMapLayer::setExtent(), QgsMapLayer::setLayerName(), QgsRasterShader::setRasterShaderFunction(), setRendererForDrawingStyle(), QgsSingleBandPseudoColorRenderer::setShader(), QgsRaster::SingleBandColorDataStyle, QgsRaster::SingleBandGray, QgsRaster::SingleBandPseudoColor, QgsMapLayer::statusChanged(), QgsRectangle::toString(), QgsCoordinateReferenceSystem::toWkt(), and tr.

Referenced by QgsRasterLayer(), readXml(), and update().

void QgsRasterLayer::setDefaultContrastEnhancement ( )
void QgsRasterLayer::setDrawingStyle ( const QString &  theDrawingStyleQString)

Overloaded version of the above function for convenience when restoring from xml.

Implemented mainly for serialisation / deserialisation of settings to xml.

Note
May be deprecated in the future! Use setDrawingStyle( DrawingStyle ) instead.

Definition at line 1126 of file qgsrasterlayer.cpp.

References QgsRaster::MultiBandColor, QgsRaster::MultiBandSingleBandGray, QgsRaster::MultiBandSingleBandPseudoColor, QgsRaster::PalettedColor, QgsRaster::PalettedMultiBandColor, QgsRaster::PalettedSingleBandGray, QgsRaster::PalettedSingleBandPseudoColor, QgsDebugMsg, setRendererForDrawingStyle(), QgsRaster::SingleBandColorDataStyle, QgsRaster::SingleBandGray, QgsRaster::SingleBandPseudoColor, and QgsRaster::UndefinedDrawingStyle.

void QgsRasterLayer::setLayerOrder ( const QStringList &  layers)
virtual

Reorders the previously selected sublayers of this layer from bottom to top.

(Useful for providers that manage their own layers, such as WMS)

Reimplemented from QgsMapLayer.

Definition at line 1179 of file qgsrasterlayer.cpp.

References mDataProvider, QgsDebugMsg, and QgsDataProvider::setLayerOrder().

void QgsRasterLayer::setRenderer ( QgsRasterRenderer theRenderer)

Set raster renderer.

Takes ownership of the renderer object

Definition at line 1202 of file qgsrasterlayer.cpp.

References mPipe, QgsDebugMsg, rendererChanged(), and QgsRasterPipe::set().

Referenced by setRendererForDrawingStyle().

void QgsRasterLayer::setRendererForDrawingStyle ( const QgsRaster::DrawingStyle theDrawingStyle)
private

Sets corresponding renderer for style.

Definition at line 225 of file qgsrasterlayer.cpp.

References QgsRasterRendererRegistry::instance(), mDataProvider, and setRenderer().

Referenced by init(), readXml(), setDataProvider(), and setDrawingStyle().

void QgsRasterLayer::setSubLayerVisibility ( QString  name,
bool  vis 
)
virtual

Set the visibility of the given sublayer name.

Reimplemented from QgsMapLayer.

Definition at line 1191 of file qgsrasterlayer.cpp.

References mDataProvider, QgsDebugMsg, and QgsDataProvider::setSubLayerVisibility().

void QgsRasterLayer::showProgress ( int  theValue)

[ data provider interface ] A wrapper function to emit a progress update signal

Definition at line 1210 of file qgsrasterlayer.cpp.

References progressUpdate().

void QgsRasterLayer::showStatusMessage ( const QString &  theMessage)
slot

Definition at line 1216 of file qgsrasterlayer.cpp.

References QgsMapLayer::statusChanged().

QStringList QgsRasterLayer::subLayers ( ) const
virtual

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

Reimplemented from QgsMapLayer.

Definition at line 1225 of file qgsrasterlayer.cpp.

References mDataProvider, and QgsRasterDataProvider::subLayers().

Referenced by QgsMapToolIdentify::identifyRasterLayer().

virtual QDateTime QgsRasterLayer::timestamp ( ) const
inlinevirtual

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

Reimplemented from QgsMapLayer.

Definition at line 364 of file qgsrasterlayer.h.

void QgsRasterLayer::triggerRepaint ( )

Emit a signal asking for a repaint.

(inherited from maplayer)

Definition at line 1279 of file qgsrasterlayer.cpp.

References QgsMapLayer::repaintRequested().

bool QgsRasterLayer::update ( )
private
void QgsRasterLayer::updateProgress ( int  theProgress,
int  theMax 
)
slot

Propagate progress updates from GDAL up to the parent app.

Definition at line 1284 of file qgsrasterlayer.cpp.

References QgsMapLayer::drawingProgress().

int QgsRasterLayer::width ( ) const

Accessor that returns the width of the (unclipped) raster.

Definition at line 1625 of file qgsrasterlayer.cpp.

References mDataProvider, and QgsRasterInterface::xSize().

Referenced by draw().

bool QgsRasterLayer::writeSymbology ( QDomNode &  layer_node,
QDomDocument &  doc,
QString &  errorMessage 
) const
protectedvirtual

Write the symbology for the layer into the docment provided.

Implements QgsMapLayer.

Definition at line 1539 of file qgsrasterlayer.cpp.

References QgsMapLayer::blendMode(), QgsMapRenderer::getBlendModeEnum(), mPipe, and QgsRasterPipe::size().

Referenced by writeXml().

bool QgsRasterLayer::writeXml ( QDomNode &  layer_node,
QDomDocument &  doc 
)
protectedvirtual

Member Data Documentation

const double QgsRasterLayer::CUMULATIVE_CUT_LOWER = 0.02
static

Default cumulative cut lower limit.

Definition at line 172 of file qgsrasterlayer.h.

Referenced by QgsRasterMinMaxWidget::QgsRasterMinMaxWidget(), and setContrastEnhancement().

const double QgsRasterLayer::CUMULATIVE_CUT_UPPER = 0.98
static

Default cumulative cut upper limit.

Definition at line 175 of file qgsrasterlayer.h.

Referenced by QgsRasterMinMaxWidget::QgsRasterMinMaxWidget(), and setContrastEnhancement().

QgsRasterDataProvider* QgsRasterLayer::mDataProvider
private
QString QgsRasterLayer::mError
private

[ data provider interface ]The error message associated with the last error

Definition at line 424 of file qgsrasterlayer.h.

Referenced by lastError().

QString QgsRasterLayer::mErrorCaption
private

[ data provider interface ] The error caption associated with the last error

Definition at line 427 of file qgsrasterlayer.h.

Referenced by lastErrorTitle().

QDateTime QgsRasterLayer::mLastModified
private

[ data provider interface ] Timestamp, the last modified time of the data source when the layer was created

Definition at line 430 of file qgsrasterlayer.h.

Referenced by setDataProvider().

QgsRasterViewPort QgsRasterLayer::mLastViewPort
private

Definition at line 432 of file qgsrasterlayer.h.

Referenced by draw(), and init().

QgsRasterPipe QgsRasterLayer::mPipe
private
QString QgsRasterLayer::mProviderKey
private

[ data provider interface ] Data provider key

Definition at line 435 of file qgsrasterlayer.h.

Referenced by providerType(), readXml(), setDataProvider(), update(), and writeXml().

LayerType QgsRasterLayer::mRasterType
private

Definition at line 437 of file qgsrasterlayer.h.

Referenced by init(), and setDataProvider().

const QString QgsRasterLayer::QSTRING_NOT_SET
private

Constant defining flag for XML and a constant that signals property not used.

Definition at line 415 of file qgsrasterlayer.h.

const double QgsRasterLayer::SAMPLE_SIZE = 250000
static

Default sample size (number of pixels) for estimated statistics/histogram calculation.

Definition at line 178 of file qgsrasterlayer.h.

const QString QgsRasterLayer::TRSTRING_NOT_SET
private

Definition at line 416 of file qgsrasterlayer.h.


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