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

Class TLcdGXYCompositeDiscretePlacementsLabelingAlgorithm

java.lang.Object

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

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

All Implemented Interfaces:

ILcdCloneable, ILcdGXYLabelingAlgorithm, Cloneable

Direct Known Subclasses:

TLcdSLDLabelingAlgorithm

public class TLcdGXYCompositeDiscretePlacementsLabelingAlgorithm
extends ALcdGXYDiscretePlacementsLabelingAlgorithm

This composite labeling algorithm combines ALcdGXYDiscretePlacementsLabelingAlgorithms into one labeling algorithm.

The difference with TLcdGXYCompositeLabelingAlgorithm is that although multiple algorithms are combined, this composite labeling algorithm respects the original label order as given TLcdCollectedLabelInfoList.getLabels(). Labels will be decluttered in this order, provided that the delegate labeling algorithms respect the order in which they receive the labels.

This composite labeling algorithm uses a ILcdGXYLabelLabelingAlgorithmProvider to assign labeling algorithms to labels. It works by creating a composite label iterator using createLabelIterator for each algorithm. It also does this using createLabelPlacementIterator and createLabelPlacementEvaluator.

The implementation of this labeling algorithm is thread-safe as long as the set labeling algorithm provider is thread-safe.

Since:

10.1

Constructor Summary

Constructors

Constructor	Description
TLcdGXYCompositeDiscretePlacementsLabelingAlgorithm(ILcdGXYLabelLabelingAlgorithmProvider<? extends ALcdGXYDiscretePlacementsLabelingAlgorithm> aAlgorithmProvider)	Creates a new TLcdGXYCompositeDiscretePlacementsLabelingAlgorithm using the given labeling algorithm provider.

Method Summary

Modifier and Type	Method	Description
TLcdGXYCompositeDiscretePlacementsLabelingAlgorithm	clone()	Makes Object.clone() public.
TLcdCollectedLabelInfoList	collectLabelInfo(List<TLcdLabelIdentifier> aLabelsToCollect, Graphics aGraphics, ILcdGXYView aGXYView)	This method returns a TLcdCollectedLabelInfoList object based on the given list of TLcdLabelIdentifiers.
protected Iterator<TLcdCollectedLabelInfo>	createLabelIterator(TLcdCollectedLabelInfoList aLabelInfoList, ILcdLabelConflictChecker aBoundsConflictChecker, ILcdGXYView aView)	Creates a new Iterator that iterates over the TLcdCollectedLabelInfos.
protected ILcdLabelPlacementEvaluator	createLabelPlacementEvaluator(TLcdCollectedLabelInfoList aLabelInfoList, ILcdLabelConflictChecker aBoundsConflictChecker, ILcdGXYView aView)	Creates a new ILcdLabelPlacementEvaluator using the given parameters.
protected Iterator<TLcdLabelPlacement>	createLabelPlacementIterator(TLcdCollectedLabelInfo aLabel, TLcdCollectedLabelInfoList aLabelInfoList, ILcdLabelConflictChecker aBoundsConflictChecker, ILcdGXYView aView)	Creates a new Iterator that iterates over the TLcdLabelPlacements for the given label.
ILcdGXYLabelLabelingAlgorithmProvider<? extends ALcdGXYDiscretePlacementsLabelingAlgorithm>	getLabelingAlgorithmProvider()	Returns the used labeling algorithm provider.

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

TLcdGXYCompositeDiscretePlacementsLabelingAlgorithm

public TLcdGXYCompositeDiscretePlacementsLabelingAlgorithm(ILcdGXYLabelLabelingAlgorithmProvider<? extends ALcdGXYDiscretePlacementsLabelingAlgorithm> aAlgorithmProvider)

Creates a new TLcdGXYCompositeDiscretePlacementsLabelingAlgorithm using the given labeling algorithm provider.

Parameters:

aAlgorithmProvider - a given labeling algorithm provider.

Method Details

getLabelingAlgorithmProvider

public ILcdGXYLabelLabelingAlgorithmProvider<? extends ALcdGXYDiscretePlacementsLabelingAlgorithm> getLabelingAlgorithmProvider()

Returns the used labeling algorithm provider.

Returns:

the used labeling algorithm provider.

clone

public TLcdGXYCompositeDiscretePlacementsLabelingAlgorithm clone()

Description copied from interface: ILcdCloneable

Makes Object.clone() public.

When for example extending from java.lang.Object, it can be implemented like this:

 public Object clone() {
   try {
     return super.clone();
   } catch ( CloneNotSupportedException e ) {
     // Cannot happen: extends from Object and implements Cloneable (see also Object.clone)
     throw new RuntimeException( e );
   }
 }
 

Specified by:

clone in interface ILcdCloneable

Overrides:

clone in class ALcdGXYDiscretePlacementsLabelingAlgorithm

See Also:

• Object.clone()

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 ALcdGXYDiscretePlacementsLabelingAlgorithm

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.

createLabelIterator

protected Iterator<TLcdCollectedLabelInfo> createLabelIterator(TLcdCollectedLabelInfoList aLabelInfoList,
 ILcdLabelConflictChecker aBoundsConflictChecker,
 ILcdGXYView aView)

Description copied from class: ALcdGXYDiscretePlacementsLabelingAlgorithm

Creates a new Iterator that iterates over the TLcdCollectedLabelInfos. The abstract labeling algorithm will continue iterating over TLcdCollectedLabelInfos as long as Iterator.hasNext() returns true. When it returns false, no more labels will be tried, and computeLabelPlacements returns. Iterator.hasNext() should always be called before calling Iterator.next(), and if it returns true, Iterator.next() should never return null.

The implementation of this method should be as independent as possible. It should not rely on createLabelPlacementIterator or createLabelPlacementEvaluator. Not respecting this might result in unexpected behaviour when wrapping or extending this class.

The returned TLcdCollectedLabelInfo should be correctly initialized, i.e. it should contain all information needed to create valid TLcdLabelPlacements using createLabelPlacementIterator. It should also always point to its corresponding TLcdCollectedLabeledObjectInfo.

Override this method to provide a custom implementation.

Specified by:

createLabelIterator in class ALcdGXYDiscretePlacementsLabelingAlgorithm

Parameters:

aLabelInfoList - the label infos object that contains all information needed to place the labels.

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

aView - the view.

Returns:

a new Iterator that iterates over TLcdCollectedLabelInfos.

createLabelPlacementIterator

protected Iterator<TLcdLabelPlacement> createLabelPlacementIterator(TLcdCollectedLabelInfo aLabel,
 TLcdCollectedLabelInfoList aLabelInfoList,
 ILcdLabelConflictChecker aBoundsConflictChecker,
 ILcdGXYView aView)

Description copied from class: ALcdGXYDiscretePlacementsLabelingAlgorithm

Creates a new Iterator that iterates over the TLcdLabelPlacements for the given label. The abstract labeling algorithm will continue iterating over TLcdLabelPlacements as long as Iterator.hasNext() returns true. When it returns false, a new label will be tried. Iterator.hasNext() should always be called before calling Iterator.next(), and if it returns true, Iterator.next() should never return null.

The implementation of this method should be as independent as possible. It should not rely on createLabelIterator or createLabelPlacementEvaluator. Not respecting this might result in unexpected behaviour when wrapping or extending this class.

The returned TLcdLabelPlacement should be correctly initialized, i.e. it should at least be able to return a valid label location, bounds rectangle and bounds rotation. It should also reference its corresponding TLcdCollectedLabelInfo.

Override this method to provide a custom implementation.

Specified by:

createLabelPlacementIterator in class ALcdGXYDiscretePlacementsLabelingAlgorithm

Parameters:

aLabel - the label for which an iterator should be created.

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

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

aView - the view.

Returns:

a new Iterator that iterates over TLcdLabelPlacements.

createLabelPlacementEvaluator

protected ILcdLabelPlacementEvaluator createLabelPlacementEvaluator(TLcdCollectedLabelInfoList aLabelInfoList,
 ILcdLabelConflictChecker aBoundsConflictChecker,
 ILcdGXYView aView)

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.

Specified by:

createLabelPlacementEvaluator in class ALcdGXYDiscretePlacementsLabelingAlgorithm

Parameters:

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

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

aView - the view

Returns:

a new LabelPlacementEvaluator

See Also:

• ILcdLabelPlacementEvaluator