A non GUI class for rendering a map layer set onto a QPainter. More...

#include <qgsmaprenderer.h>

Public Types
enum	OutputUnits { Millimeters, Pixels }
	Output units for pen width and point marker width/height. More...
enum	BlendMode { BlendNormal, BlendLighten, BlendScreen, BlendDodge, BlendAddition, BlendDarken, BlendMultiply, BlendBurn, BlendOverlay, BlendSoftLight, BlendHardLight, BlendDifference, BlendSubtract, BlendSource, BlendDestinationOver, BlendClear, BlendDestination, BlendSourceIn, BlendDestinationIn, BlendSourceOut, BlendDestinationOut, BlendSourceAtop, BlendDestinationAtop, BlendXor }
	Blending modes enum defining the available composition modes that can be used when rendering a layer. More...

Public Slots
Q_DECL_DEPRECATED void	onDrawingProgress (int current, int total)

Signals
void	drawingProgress (int current, int total)
Q_DECL_DEPRECATED void	hasCrsTransformEnabled (bool flag)
	This signal is emitted when CRS transformation is enabled/disabled.
void	hasCrsTransformEnabledChanged (bool flag)
	This signal is emitted when CRS transformation is enabled/disabled.
void	destinationSrsChanged ()
void	updateMap ()
void	mapUnitsChanged ()
void	drawError (QgsMapLayer *)
	emitted when layer's draw() returned false
void	extentsChanged ()
	emitted when the current extent gets changed
void	datumTransformInfoRequested (const QgsMapLayer *ml, const QString &srcAuthId, const QString &destAuthId) const
	Notifies higher level components to show the datum transform dialog and add a QgsLayerCoordinateTransformInfo for that layer.

Public Member Functions
	QgsMapRenderer ()
	constructor
	~QgsMapRenderer ()
	destructor
void	render (QPainter painter, double forceWidthScale=0)
	starts rendering
bool	setExtent (const QgsRectangle &extent)
	sets extent and checks whether suitable (returns false if not)
QgsRectangle	extent () const
	returns current extent
const QgsMapToPixel *	coordinateTransform ()
double	scale () const
	Scale denominator.
void	setScale (double scale)
	Sets scale for scale based visibility.
double	mapUnitsPerPixel () const
int	width () const
int	height () const
void	updateScale ()
	Recalculate the map scale.
QGis::UnitType	mapUnits () const
void	setMapUnits (QGis::UnitType u)
void	enableOverviewMode (bool isOverview=true)
	sets whether map image will be for overview
void	setOutputSize (QSize size, int dpi)
void	setOutputSize (QSizeF size, double dpi)
double	outputDpi ()
	accessor for output dpi
QSize	outputSize ()
	accessor for output size
QSizeF	outputSizeF ()
QgsRectangle	layerExtentToOutputExtent (QgsMapLayer *theLayer, QgsRectangle extent)
	transform bounding box from layer's CRS to output CRS
QgsRectangle	outputExtentToLayerExtent (QgsMapLayer *theLayer, QgsRectangle extent)
	transform bounding box from output CRS to layer's CRS
QgsPoint	layerToMapCoordinates (QgsMapLayer *theLayer, QgsPoint point)
	transform point coordinates from layer's CRS to output CRS
QgsRectangle	layerToMapCoordinates (QgsMapLayer *theLayer, QgsRectangle rect)
	transform rectangle from layer's CRS to output CRS
QgsPoint	mapToLayerCoordinates (QgsMapLayer *theLayer, QgsPoint point)
	transform point coordinates from output CRS to layer's CRS
QgsRectangle	mapToLayerCoordinates (QgsMapLayer *theLayer, QgsRectangle rect)
	transform rectangle from output CRS to layer's CRS
void	setProjectionsEnabled (bool enabled)
	sets whether to use projections for this layer set
bool	hasCrsTransformEnabled () const
	returns true if projections are enabled for this layer set
void	setDestinationCrs (const QgsCoordinateReferenceSystem &crs, bool refreshCoordinateTransformInfo=true, bool transformExtent=true)
	sets destination coordinate reference system
const QgsCoordinateReferenceSystem &	destinationCrs () const
	returns CRS of destination coordinate reference system
void	setOutputUnits (OutputUnits u)
OutputUnits	outputUnits () const
QgsRectangle	fullExtent ()
	returns current extent of layer set
QStringList &	layerSet ()
	returns current layer set
void	setLayerSet (const QStringList &layers)
	change current layer set
void	updateFullExtent ()
	updates extent of the layer set
bool	readXML (QDomNode &theNode)
	read settings
bool	writeXML (QDomNode &theNode, QDomDocument &theDoc)
	write settings
QgsRenderContext *	rendererContext ()
	Accessor for render context.
QgsLabelingEngineInterface *	labelingEngine ()
	Labeling engine (NULL if there's no custom engine)
void	setLabelingEngine (QgsLabelingEngineInterface *iface)
	Set labeling engine.
void	addLayerCoordinateTransform (const QString &layerId, const QString &srcAuthId, const QString &destAuthId, int srcDatumTransform=-1, int destDatumTransform=-1)
void	clearLayerCoordinateTransforms ()
const QgsCoordinateTransform *	transformation (const QgsMapLayer *layer) const
const QgsMapSettings &	mapSettings ()
	bridge to QgsMapSettings
bool	splitLayersExtent (QgsMapLayer *layer, QgsRectangle &extent, QgsRectangle &r2)
	Convenience function to project an extent into the layer source CRS, but also split it into two extents if it crosses the +/- 180 degree line.

Static Public Member Functions
static QPainter::CompositionMode	getCompositionMode (const QgsMapRenderer::BlendMode &blendMode)
	Returns a QPainter::CompositionMode corresponding to a BlendMode.
static QgsMapRenderer::BlendMode	getBlendModeEnum (const QPainter::CompositionMode &blendMode)
	Returns a BlendMode corresponding to a QPainter::CompositionMode.

Protected Member Functions
void	adjustExtentToSize ()
	adjust extent to fit the pixmap size

Protected Attributes
double	mMapUnitsPerPixel
	map units per pixel
double	mScale
	Map scale denominator at its current zoom level.
QgsScaleCalculator *	mScaleCalculator
	scale calculator
QgsRectangle	mExtent
	current extent to be drawn
QgsRectangle	mLastExtent
	Last extent to we drew so we know if we can used layer render caching or not.
bool	mOverview
	indicates whether it's map image for overview
QSizeF	mSize
bool	mProjectionsEnabled
	detemines whether on the fly projection support is enabled
QgsCoordinateReferenceSystem *	mDestCRS
	destination spatial reference system of the projection
QStringList	mLayerSet
	stores array of layers to be rendered (identified by string)
QgsRectangle	mFullExtent
	full extent of the layer set
QgsDistanceArea *	mDistArea
	tool for measuring
QgsRenderContext	mRenderContext
	Encapsulates context of rendering.
OutputUnits	mOutputUnits
	Output units.
QgsLabelingEngineInterface *	mLabelingEngine
	Labeling engine (NULL by default)
QMutex	mRenderMutex
	Locks rendering loop for concurrent draws.
QgsMapSettings	mMapSettings
	map settings - used only for export in mapSettings() for use in classes that deal with QgsMapSettings
QHash< QString, QgsLayerCoordinateTransform >	mLayerCoordinateTransformInfo

Static Protected Attributes
static bool	mDrawing = false
	indicates drawing in progress

Detailed Description

A non GUI class for rendering a map layer set onto a QPainter.

Member Enumeration Documentation

enum QgsMapRenderer::BlendMode

Blending modes enum defining the available composition modes that can be used when rendering a layer.

Enumerator:

BlendNormal
BlendLighten
BlendScreen
BlendDodge
BlendAddition
BlendDarken
BlendMultiply
BlendBurn
BlendOverlay
BlendSoftLight
BlendHardLight
BlendDifference
BlendSubtract
BlendSource
BlendDestinationOver
BlendClear
BlendDestination
BlendSourceIn
BlendDestinationIn
BlendSourceOut
BlendDestinationOut
BlendSourceAtop
BlendDestinationAtop
BlendXor

enum QgsMapRenderer::OutputUnits

Output units for pen width and point marker width/height.

Enumerator:

Millimeters
Pixels

Constructor & Destructor Documentation

QgsMapRenderer::QgsMapRenderer ( )

constructor

QgsMapRenderer::~QgsMapRenderer ( )

destructor

Member Function Documentation

void QgsMapRenderer::addLayerCoordinateTransform	(	const QString &	layerId,
		const QString &	srcAuthId,
		const QString &	destAuthId,
		int	srcDatumTransform = `-1`,
		int	destDatumTransform = `-1`
	)

void QgsMapRenderer::adjustExtentToSize ( )

protected

adjust extent to fit the pixmap size

void QgsMapRenderer::clearLayerCoordinateTransforms ( )

const QgsMapToPixel* QgsMapRenderer::coordinateTransform ( )

inline

void QgsMapRenderer::datumTransformInfoRequested	(	const QgsMapLayer *	ml,
		const QString &	srcAuthId,
		const QString &	destAuthId
	)		const

signal

Notifies higher level components to show the datum transform dialog and add a QgsLayerCoordinateTransformInfo for that layer.

const QgsCoordinateReferenceSystem & QgsMapRenderer::destinationCrs ( ) const

returns CRS of destination coordinate reference system

void QgsMapRenderer::destinationSrsChanged ( )

signal

void QgsMapRenderer::drawError ( QgsMapLayer * )

signal

emitted when layer's draw() returned false

void QgsMapRenderer::drawingProgress	(	int	current,
		int	total
	)

signal

Deprecated:: in 2.4 - not emitted anymore

void QgsMapRenderer::enableOverviewMode ( bool isOverview = true )

inline

sets whether map image will be for overview

QgsRectangle QgsMapRenderer::extent ( ) const

returns current extent

void QgsMapRenderer::extentsChanged ( )

signal

emitted when the current extent gets changed

Note: added in 2.4

QgsRectangle QgsMapRenderer::fullExtent ( )

returns current extent of layer set

QgsMapRenderer::BlendMode QgsMapRenderer::getBlendModeEnum ( const QPainter::CompositionMode & blendMode )

static

Returns a BlendMode corresponding to a QPainter::CompositionMode.

QPainter::CompositionMode QgsMapRenderer::getCompositionMode ( const QgsMapRenderer::BlendMode & blendMode )

static

Returns a QPainter::CompositionMode corresponding to a BlendMode.

Returns a QPainter::CompositionMode corresponding to a QgsMapRenderer::BlendMode.

bool QgsMapRenderer::hasCrsTransformEnabled ( ) const

returns true if projections are enabled for this layer set

Q_DECL_DEPRECATED void QgsMapRenderer::hasCrsTransformEnabled ( bool flag )

signal

This signal is emitted when CRS transformation is enabled/disabled.

Parameters

flag	true if transformation is enabled.

Deprecated:: Use hasCrsTransformEnabledChanged( bool flag ) to avoid conflict with method of the same name).

void QgsMapRenderer::hasCrsTransformEnabledChanged ( bool flag )

signal

This signal is emitted when CRS transformation is enabled/disabled.

Parameters

flag	true if transformation is enabled.

Note: Added in 2.4

int QgsMapRenderer::height ( ) const

inline

QgsLabelingEngineInterface* QgsMapRenderer::labelingEngine ( )

inline

Labeling engine (NULL if there's no custom engine)

QgsRectangle QgsMapRenderer::layerExtentToOutputExtent	(	QgsMapLayer *	theLayer,
		QgsRectangle	extent
	)

transform bounding box from layer's CRS to output CRS

See Also: layerToMapCoordinates( QgsMapLayer* theLayer, QgsRectangle rect ) if you want to transform a rectangle

Returns: a bounding box (aligned rectangle) containing the transformed extent

QStringList & QgsMapRenderer::layerSet ( )

returns current layer set

QgsPoint QgsMapRenderer::layerToMapCoordinates	(	QgsMapLayer *	theLayer,
		QgsPoint	point
	)

transform point coordinates from layer's CRS to output CRS

Returns: the transformed point

QgsRectangle QgsMapRenderer::layerToMapCoordinates	(	QgsMapLayer *	theLayer,
		QgsRectangle	rect
	)

transform rectangle from layer's CRS to output CRS

See Also: layerExtentToOutputExtent() if you want to transform a bounding box

Returns: the transformed rectangle

const QgsMapSettings & QgsMapRenderer::mapSettings ( )

bridge to QgsMapSettings

Note: added in 2.4

QgsPoint QgsMapRenderer::mapToLayerCoordinates	(	QgsMapLayer *	theLayer,
		QgsPoint	point
	)

transform point coordinates from output CRS to layer's CRS

Returns: the transformed point

QgsRectangle QgsMapRenderer::mapToLayerCoordinates	(	QgsMapLayer *	theLayer,
		QgsRectangle	rect
	)

transform rectangle from output CRS to layer's CRS

See Also: outputExtentToLayerExtent() if you want to transform a bounding box

Returns: the transformed rectangle

QGis::UnitType QgsMapRenderer::mapUnits ( ) const

void QgsMapRenderer::mapUnitsChanged ( )

signal

double QgsMapRenderer::mapUnitsPerPixel ( ) const

inline

void QgsMapRenderer::onDrawingProgress	(	int	current,
		int	total
	)

slot

Deprecated:: in 2.4 - does nothing

double QgsMapRenderer::outputDpi ( )

accessor for output dpi

QgsRectangle QgsMapRenderer::outputExtentToLayerExtent	(	QgsMapLayer *	theLayer,
		QgsRectangle	extent
	)

transform bounding box from output CRS to layer's CRS

See Also: mapToLayerCoordinates( QgsMapLayer* theLayer,QgsRectangle rect ) if you want to transform a rectangle

Returns: a bounding box (aligned rectangle) containing the transformed extent

QSize QgsMapRenderer::outputSize ( )

accessor for output size

QSizeF QgsMapRenderer::outputSizeF ( )

OutputUnits QgsMapRenderer::outputUnits ( ) const

inline

bool QgsMapRenderer::readXML ( QDomNode & theNode )

read settings

void QgsMapRenderer::render	(	QPainter *	painter,
		double *	forceWidthScale = `0`
	)

starts rendering

Parameters

painter	painter to render to
forceWidthScale	Force a specific scale factor for line widths and marker sizes. Automatically calculated from output device DPI if 0

QgsRenderContext* QgsMapRenderer::rendererContext ( )

inline

Accessor for render context.

double QgsMapRenderer::scale ( ) const

inline

Scale denominator.

void QgsMapRenderer::setDestinationCrs	(	const QgsCoordinateReferenceSystem &	crs,
		bool	refreshCoordinateTransformInfo = `true`,
		bool	transformExtent = `true`
	)

sets destination coordinate reference system

bool QgsMapRenderer::setExtent ( const QgsRectangle & extent )

sets extent and checks whether suitable (returns false if not)

void QgsMapRenderer::setLabelingEngine ( QgsLabelingEngineInterface * iface )

Set labeling engine.

Previous engine (if any) is deleted. Takes ownership of the engine.

void QgsMapRenderer::setLayerSet ( const QStringList & layers )

change current layer set

void QgsMapRenderer::setMapUnits ( QGis::UnitType u )

void QgsMapRenderer::setOutputSize	(	QSize	size,
		int	dpi
	)

void QgsMapRenderer::setOutputSize	(	QSizeF	size,
		double	dpi
	)

void QgsMapRenderer::setOutputUnits ( OutputUnits u )

inline

void QgsMapRenderer::setProjectionsEnabled ( bool enabled )

sets whether to use projections for this layer set

void QgsMapRenderer::setScale ( double scale )

inline

Sets scale for scale based visibility.

Normally, the scale is calculated automatically. This function is only used to force a preview scale (e.g. for print composer)

bool QgsMapRenderer::splitLayersExtent	(	QgsMapLayer *	layer,
		QgsRectangle &	extent,
		QgsRectangle &	r2
	)

Convenience function to project an extent into the layer source CRS, but also split it into two extents if it crosses the +/- 180 degree line.

Modifies the given extent to be in the source CRS coordinates, and if it was split, returns true, and also sets the contents of the r2 parameter

const QgsCoordinateTransform * QgsMapRenderer::transformation ( const QgsMapLayer * layer ) const

void QgsMapRenderer::updateFullExtent ( )

updates extent of the layer set

void QgsMapRenderer::updateMap ( )

signal

Deprecated:: in 2.4 - not emitted anymore

void QgsMapRenderer::updateScale ( )

Recalculate the map scale.

int QgsMapRenderer::width ( ) const

inline

bool QgsMapRenderer::writeXML	(	QDomNode &	theNode,
		QDomDocument &	theDoc
	)

write settings

Member Data Documentation

QgsCoordinateReferenceSystem* QgsMapRenderer::mDestCRS

protected

destination spatial reference system of the projection

QgsDistanceArea* QgsMapRenderer::mDistArea

protected

tool for measuring

bool QgsMapRenderer::mDrawing = false

staticprotected

indicates drawing in progress

QgsRectangle QgsMapRenderer::mExtent

protected

current extent to be drawn

QgsRectangle QgsMapRenderer::mFullExtent

protected

full extent of the layer set

QgsLabelingEngineInterface* QgsMapRenderer::mLabelingEngine

protected

Labeling engine (NULL by default)

QgsRectangle QgsMapRenderer::mLastExtent

protected

Last extent to we drew so we know if we can used layer render caching or not.

Note there are no accessors for this as it is intended to internal use only.

QHash< QString, QgsLayerCoordinateTransform > QgsMapRenderer::mLayerCoordinateTransformInfo

protected

QStringList QgsMapRenderer::mLayerSet

protected

stores array of layers to be rendered (identified by string)

QgsMapSettings QgsMapRenderer::mMapSettings

protected

map settings - used only for export in mapSettings() for use in classes that deal with QgsMapSettings

double QgsMapRenderer::mMapUnitsPerPixel

protected

map units per pixel

OutputUnits QgsMapRenderer::mOutputUnits

protected

Output units.

bool QgsMapRenderer::mOverview

protected

indicates whether it's map image for overview

bool QgsMapRenderer::mProjectionsEnabled

protected

detemines whether on the fly projection support is enabled

QgsRenderContext QgsMapRenderer::mRenderContext

protected

Encapsulates context of rendering.

QMutex QgsMapRenderer::mRenderMutex

protected

Locks rendering loop for concurrent draws.

double QgsMapRenderer::mScale

protected

Map scale denominator at its current zoom level.

QgsScaleCalculator* QgsMapRenderer::mScaleCalculator

protected

scale calculator

QSizeF QgsMapRenderer::mSize

protected

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

/tmp/buildd/qgis-2.6.0+wheezy1/src/core/qgsmaprenderer.h
/tmp/buildd/qgis-2.6.0+wheezy1/src/core/qgsmaprenderer.cpp

Public Types

Public Slots

Signals

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Static Protected Attributes

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation