Package com.luciad.ogc.sld.view.gxy

Class TLcdSLDLabelingAlgorithm

java.lang.Object

com.luciad.view.gxy.labeling.algorithm.discrete.ALcdGXYDiscretePlacementsLabelingAlgorithm

com.luciad.view.gxy.labeling.algorithm.discrete.TLcdGXYCompositeDiscretePlacementsLabelingAlgorithm

com.luciad.ogc.sld.view.gxy.TLcdSLDLabelingAlgorithm

All Implemented Interfaces:

ILcdCloneable, ILcdGXYLabelingAlgorithm, Cloneable

public class TLcdSLDLabelingAlgorithm
extends TLcdGXYCompositeDiscretePlacementsLabelingAlgorithm

Extension of TLcdGXYCompositeLabelingAlgorithm that computes label locations for layers that have a TLcdSLDFeatureTypeStylePainter as label painter.

Since:

11.0

Constructor Summary

Constructors

Constructor	Description
TLcdSLDLabelingAlgorithm()	Constructs a new labeling algorithm that prefers static labels over dynamic ones for non-curved labels (see TLcdSLDLabelingAlgorithm(boolean)) and that enables label placement conflict resolution (label decluttering).
TLcdSLDLabelingAlgorithm(boolean aStaticLabels)	Constructs a new labeling algorithm with label placement conflict resolution (label decluttering) enabled and with the given option to prefer static labels over dynamic ones.
TLcdSLDLabelingAlgorithm(boolean aStaticLabels, boolean aConflictResolutionEnabled)	Constructs a new labeling algorithm with the given options to prefer static labels over dynamic ones for non-curved labels and to enable label placement conflict resolution (label decluttering).

Method Summary

Modifier and Type	Method	Description
boolean	canHandle(TLcdLabelIdentifier aLabel)	Returns if this algorithm can handle the given label.
TLcdCollectedLabelInfoList	collectLabelInfo(List<TLcdLabelIdentifier> aLabelsToCollect, Graphics aGraphics, ILcdGXYView aGXYView)	This method returns a TLcdCollectedLabelInfoList object based on the given list of TLcdLabelIdentifiers.
protected ILcdLabelPlacementEvaluator	createLabelPlacementEvaluator(TLcdCollectedLabelInfoList aCollectedLabelInfoList, ILcdLabelConflictChecker aLabelConflictChecker, ILcdGXYView aGXYView)	Creates a new ILcdLabelPlacementEvaluator using the given parameters.
protected TLcdSLDFeatureTypeStylePainter	getFeatureTypeStylePainter(TLcdLabelIdentifier aLabel)	Returns the TLcdSLDFeatureTypeStylePainter that is responsible for painting the given label.

Methods inherited from class com.luciad.view.gxy.labeling.algorithm.discrete.TLcdGXYCompositeDiscretePlacementsLabelingAlgorithm

clone, createLabelIterator, createLabelPlacementIterator, getLabelingAlgorithmProvider

Methods inherited from class com.luciad.view.gxy.labeling.algorithm.discrete.ALcdGXYDiscretePlacementsLabelingAlgorithm

computeLabelPlacements

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

TLcdSLDLabelingAlgorithm

public TLcdSLDLabelingAlgorithm()

Constructs a new labeling algorithm that prefers static labels over dynamic ones for non-curved labels (see TLcdSLDLabelingAlgorithm(boolean)) and that enables label placement conflict resolution (label decluttering).

TLcdSLDLabelingAlgorithm

public TLcdSLDLabelingAlgorithm(boolean aStaticLabels)

Constructs a new labeling algorithm with label placement conflict resolution (label decluttering) enabled and with the given option to prefer static labels over dynamic ones. Static labels are labels that don't move during navigation or due to decluttering. This is for example useful for cases where you need consistent consistent label positions over multiple repaints, such as in a (Tiled) WMS or WMTS server implementation. An exception is made for curved labels, for which the placement is always dynamic: their target use case is the labeling of paths (like streets, rivers ...), which benefits from dynamic placement to optimize the label readability and to support label repeating.

Parameters:

aStaticLabels - sets whether static labels are preferred over dynamic ones for non-curved labels

Since:

2017.0

TLcdSLDLabelingAlgorithm

public TLcdSLDLabelingAlgorithm(boolean aStaticLabels,
 boolean aConflictResolutionEnabled)

Constructs a new labeling algorithm with the given options to prefer static labels over dynamic ones for non-curved labels and to enable label placement conflict resolution (label decluttering).

Parameters:

aStaticLabels - sets whether static labels are preferred over dynamic ones for non-curved labels

aConflictResolutionEnabled - sets whether label placement conflict resolution should be enabled

Since:

2021.0

Method Details

canHandle

public boolean canHandle(TLcdLabelIdentifier aLabel)

Returns if this algorithm can handle the given label. Returns true if a TLcdSLDFeatureTypeStylePainter is used as label painter for the layer of the given label.

Parameters:

aLabel - the label to handle

Returns:

if this algorithm can handle the label

collectLabelInfo

public TLcdCollectedLabelInfoList collectLabelInfo(List<TLcdLabelIdentifier> aLabelsToCollect,
 Graphics aGraphics,
 ILcdGXYView aGXYView)

Description copied from interface: ILcdGXYLabelingAlgorithm

This method returns a TLcdCollectedLabelInfoList object based on the given list of TLcdLabelIdentifiers. The returned TLcdCollectedLabelInfoList should contain a TLcdCollectedLabelInfo object for each label that should be placed.

Each TLcdCollectedLabelInfo should also contain all information needed by computeLabelPlacements to place the labels. In order to enable correct asynchronous label placing, all calls to the layer and the (label) painters should be done in this method. The results should then be stored in the info objects.

It is possible that the returned TLcdCollectedLabelInfoList doesn't contain a TLcdCollectedLabelInfo object for every given TLcdLabelIdentifier. In that case the missing labels are not placed.

Specified by:

collectLabelInfo in interface ILcdGXYLabelingAlgorithm

Overrides:

collectLabelInfo in class TLcdGXYCompositeDiscretePlacementsLabelingAlgorithm

Parameters:

aLabelsToCollect - the labels for which a TLcdCollectedLabelInfoList should be created.

aGraphics - the graphics.

aGXYView - the view.

Returns:

a TLcdCollectedLabelInfoList which contains all the information needed to place the labels.

createLabelPlacementEvaluator

protected ILcdLabelPlacementEvaluator createLabelPlacementEvaluator(TLcdCollectedLabelInfoList aCollectedLabelInfoList,
 ILcdLabelConflictChecker aLabelConflictChecker,
 ILcdGXYView aGXYView)

Description copied from class: ALcdGXYDiscretePlacementsLabelingAlgorithm

Creates a new ILcdLabelPlacementEvaluator using the given parameters. It evaluates the placements returned by createLabelPlacementIterator, and returns a PlacementResult to denote if the placement should be used for its label or not.

The following actions are undertaken for the following placement results :

• PlacementResult.SUCCESS : the given label placement will be used for its label, it will be added to the list of placed labels, and it will be added to the given ILcdLabelConflictChecker. After that, ILcdLabelPlacementEvaluator.placementApplied will be called and no more placements are tried for the label.
• PlacementResult.FALLBACK : the abstract algorithm will try to find an other placements which returns PlacementResult.SUCCESS. When no such placement is found, this placement will be added to the list of placed labels, and it will be added to the given ILcdLabelConflictChecker. After that, ILcdLabelPlacementEvaluator.placementApplied will be called.
• PlacementResult.TRY_NEW_PLACEMENT : the abstract algorithm will try to find an other placement which returns PlacementResult.SUCCESS or PlacementResult.FALLBACK. When no such placement is found, ILcdLabelPlacementEvaluator.noPlacementApplied is called.
• PlacementResult.FAILED : the abstract algorithm will immediately call ILcdLabelPlacementEvaluator.noPlacementApplied and will not try to find other placements for the label.

Override this method to provide a custom implementation.

Overrides:

createLabelPlacementEvaluator in class TLcdGXYCompositeDiscretePlacementsLabelingAlgorithm

Parameters:

aCollectedLabelInfoList - the info object that contains all information needed to place the labels.

aLabelConflictChecker - the bounds conflict checker to be used when evaluating label placements.

aGXYView - the view

Returns:

a new LabelPlacementEvaluator

See Also:

• ILcdLabelPlacementEvaluator

getFeatureTypeStylePainter

protected TLcdSLDFeatureTypeStylePainter getFeatureTypeStylePainter(TLcdLabelIdentifier aLabel)

Returns the TLcdSLDFeatureTypeStylePainter that is responsible for painting the given label. If no such painter can be found, returns null.

Parameters:

aLabel - the label

Returns:

the feature type style painter for the given label