Main Pal labelling class. More...

#include <pal.h>

Public Types
typedef bool(*	FnIsCancelled) (void *ctx)

Public Member Functions
	Pal ()
	Create an new pal instance. More...

	~Pal ()
	delete an instance More...

Layer *	addLayer (QgsAbstractLabelProvider *provider, const QString &layerName, QgsPalLayerSettings::Placement arrangement, double defaultPriority, bool active, bool toLabel, bool displayAll=false)
	add a new layer More...

Problem *	extractProblem (double bbox[4])

int	getLineP ()
	get maximum # candidates to generate for line features More...

int	getPointP ()
	get # candidates to generate for point features More...

int	getPolyP ()
	get maximum # candidates to generate for polygon features More...

SearchMethod	getSearch ()
	get the search method in use More...

bool	getShowPartial ()
	Get flag show partial label. More...

bool	isCancelled ()
	Check whether the job has been cancelled. More...

QList< LabelPosition * > *	labeller (double bbox[4], PalStat **stats, bool displayAll)
	the labeling machine Will extract all active layers More...

void	registerCancellationCallback (FnIsCancelled fnCancelled, void *context)
	Register a function that returns whether this job has been cancelled - PAL calls it during the computation. More...

void	removeLayer (Layer *layer)
	remove a layer More...

void	setLineP (int line_p)
	set maximum # candidates to generate for lines features Higher the value is, longer Pal::labeller will spend time More...

void	setPointP (int point_p)
	set # candidates to generate for points features Higher the value is, longer Pal::labeller will spend time More...

void	setPolyP (int poly_p)
	set maximum # candidates to generate for polygon features Higher the value is, longer Pal::labeller will spend time More...

void	setSearch (SearchMethod method)
	Select the search method to use. More...

void	setShowPartial (bool show)
	Set flag show partial label. More...

QList< LabelPosition * > *	solveProblem (Problem *prob, bool displayAll)

Friends
class	FeaturePart

class	Layer

class	Problem

Detailed Description

Main Pal labelling class.

A pal object will contains layers and global information such as which search method will be used.

Note: not available in Python bindings

Definition at line 84 of file pal.h.

Member Typedef Documentation

◆ FnIsCancelled

typedef bool( * pal::Pal::FnIsCancelled) (void *ctx)

Definition at line 138 of file pal.h.

Constructor & Destructor Documentation

◆ Pal()

Pal::Pal ( )

Create an new pal instance.

Definition at line 53 of file pal.cpp.

◆ ~Pal()

Pal::~Pal ( )

delete an instance

Definition at line 95 of file pal.cpp.

Member Function Documentation

◆ addLayer()

Layer * Pal::addLayer	(	QgsAbstractLabelProvider *	provider,
		const QString &	layerName,
		QgsPalLayerSettings::Placement	arrangement,
		double	defaultPriority,
		bool	active,
		bool	toLabel,
		bool	displayAll = `false`
	)

add a new layer

Parameters

provider	Provider associated with the layer
layerName	layer's name
arrangement	Howto place candidates
defaultPriority	layer's prioriry (0 is the best, 1 the worst)
active	is the layer is active (currently displayed)
toLabel	the layer will be labeled only if toLablel is true
displayAll	if true, all features will be labelled even though overlaps occur

Exceptions

PalException::LayerExists

Todo:: add symbolUnit

Definition at line 108 of file pal.cpp.

◆ extractProblem()

Problem * Pal::extractProblem ( double bbox[4] )

Definition at line 512 of file pal.cpp.

◆ getLineP()

int Pal::getLineP ( )

get maximum # candidates to generate for line features

Definition at line 604 of file pal.cpp.

◆ getPointP()

int Pal::getPointP ( )

get # candidates to generate for point features

Definition at line 599 of file pal.cpp.

◆ getPolyP()

int Pal::getPolyP ( )

get maximum # candidates to generate for polygon features

Definition at line 609 of file pal.cpp.

◆ getSearch()

SearchMethod Pal::getSearch ( )

get the search method in use

Returns: the search method

Definition at line 629 of file pal.cpp.

◆ getShowPartial()

bool Pal::getShowPartial ( )

Get flag show partial label.

Returns: value of flag

Definition at line 624 of file pal.cpp.

◆ isCancelled()

bool pal::Pal::isCancelled ( )

inline

Check whether the job has been cancelled.

Definition at line 144 of file pal.h.

◆ labeller()

QList< LabelPosition * > * Pal::labeller	(	double	bbox[4],
		PalStat **	stats,
		bool	displayAll
	)

the labeling machine Will extract all active layers

Parameters

bbox	map extent
stats	A PalStat object (can be NULL)
displayAll	if true, all feature will be labelled even though overlaps occur

Returns: A list of label to display on map

Definition at line 454 of file pal.cpp.

◆ registerCancellationCallback()

void Pal::registerCancellationCallback	(	Pal::FnIsCancelled	fnCancelled,
		void *	context
	)

Register a function that returns whether this job has been cancelled - PAL calls it during the computation.

Definition at line 506 of file pal.cpp.

◆ removeLayer()

void Pal::removeLayer ( Layer * layer )

remove a layer

Parameters

layer layer to remove

Definition at line 81 of file pal.cpp.

◆ setLineP()

void Pal::setLineP ( int line_p )

set maximum # candidates to generate for lines features Higher the value is, longer Pal::labeller will spend time

Parameters

line_p maximum # candidates for a line

Definition at line 548 of file pal.cpp.

◆ setPointP()

void Pal::setPointP ( int point_p )

set # candidates to generate for points features Higher the value is, longer Pal::labeller will spend time

Parameters

point_p # candidates for a point

Definition at line 542 of file pal.cpp.

◆ setPolyP()

void Pal::setPolyP ( int poly_p )

set maximum # candidates to generate for polygon features Higher the value is, longer Pal::labeller will spend time

Parameters

poly_p maximum # candidate for a polygon

Definition at line 554 of file pal.cpp.

◆ setSearch()

void Pal::setSearch ( SearchMethod method )

Select the search method to use.

For interactive mapping using CHAIN is a good idea because it is the fastest. Other methods, ordered by speedness, are POPMUSIC_TABU, POPMUSIC_CHAIN and POPMUSIC_TABU_CHAIN, defined in pal::_searchMethod enumeration

Parameters

method the method to use

Definition at line 634 of file pal.cpp.

◆ setShowPartial()

void Pal::setShowPartial ( bool show )

Set flag show partial label.

Parameters

show	flag value

Definition at line 594 of file pal.cpp.

◆ solveProblem()

QList< LabelPosition * > * Pal::solveProblem	(	Problem *	prob,
		bool	displayAll
	)

Definition at line 517 of file pal.cpp.

Friends And Related Function Documentation

◆ FeaturePart

friend class FeaturePart

friend

Definition at line 87 of file pal.h.

◆ Layer

friend class Layer

friend

Definition at line 88 of file pal.h.

◆ Problem

friend class Problem

friend

Definition at line 86 of file pal.h.

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

/tmp/buildd/qgis-2.18.21+99unstable/src/core/pal/pal.h
/tmp/buildd/qgis-2.18.21+99unstable/src/core/pal/pal.cpp

Public Types

Public Member Functions

Friends

Detailed Description

Member Typedef Documentation

◆ FnIsCancelled

Constructor & Destructor Documentation

◆ Pal()

◆ ~Pal()

Member Function Documentation

◆ addLayer()

◆ extractProblem()

◆ getLineP()

◆ getPointP()

◆ getPolyP()

◆ getSearch()

◆ getShowPartial()

◆ isCancelled()

◆ labeller()

◆ registerCancellationCallback()

◆ removeLayer()

◆ setLineP()

◆ setPointP()

◆ setPolyP()

◆ setSearch()

◆ setShowPartial()

◆ solveProblem()

Friends And Related Function Documentation

◆ FeaturePart

◆ Layer

◆ Problem