TLcdGXYCurvedPathLabelingAlgorithm (LuciadLightspeed API documentation)

java.lang.Object
- com.luciad.view.gxy.labeling.algorithm.discrete.ALcdGXYDiscretePlacementsLabelingAlgorithm
- - com.luciad.view.gxy.labeling.algorithm.discrete.TLcdGXYCurvedPathLabelingAlgorithm

All Implemented Interfaces:

ILcdCloneable, ILcdGXYLabelingAlgorithm, Cloneable
```
public class TLcdGXYCurvedPathLabelingAlgorithm
extends ALcdGXYDiscretePlacementsLabelingAlgorithm
```
This labeling algorithm tries to find a valid position for a curved path text label. To do this it uses a given TLcdGXYCurvedPathLabelPainter.
This labeling algorithm does not use the labelBoundsSFCT() method of the given TLcdGXYCurvedPathLabelPainter to calculate the label bounds. Instead it retrieves the settings of this label painter (halo enabled/thickness, used font, ...) to calculate the bounds itself.
This labeling algorithm depends on TLcdGXYCurvedPathLabelLocation in order to work. Only 3 fields of the label location are actually set :
- TLcdGXYCurvedPathLabelLocation.getLocationIndex() (to -1)
- TLcdGXYCurvedPathLabelLocation.getSubPathIndex()
- TLcdGXYCurvedPathLabelLocation.getAWTPathParameter()
The rest of the fields are not used since these field completely determine the position of the label.
This labeling algorithm will only work when a TLcdGXYCurvedPathLabelPainter is used to actually paint the labels. This label painter also works with TLcdGXYCurvedPathLabelLocations, and uses the 'sub path index' and 'awt path parameter' fields.
The implementation of this labeling algorithm is thread-safe, as long as the ILcdGXYLabelingPathProvider set in the given TLcdGXYCurvedPathLabelPainter is thread-safe.
Since:

11.0

Constructor Summary

Constructors
Constructor and Description
`TLcdGXYCurvedPathLabelingAlgorithm(ILcdGXYLabelPainterProvider aGXYCurvedPathLabelPainterProvider)` Creates a new `TLcdGXYCurvedPathLabelingAlgorithm` which uses the given `ILcdGXYLabelPainterProvider` to retrieve a `TLcdGXYCurvedPathLabelPainter`.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`TLcdGXYCurvedPathLabelingAlgorithm`	`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 `TLcdLabelIdentifier`s.
`protected Iterator<TLcdCollectedLabelInfo>`	`createLabelIterator(TLcdCollectedLabelInfoList aLabelInfoList, ILcdLabelConflictChecker aBoundsConflictChecker, ILcdGXYView aView)` Creates a new `Iterator` that iterates over the `TLcdCollectedLabelInfo`s.
`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 `TLcdLabelPlacement`s for the given label.
`ILcdGXYMultiLabelPriorityProvider`	`getLabelPriorityProvider()` Returns the label placing priority provider.
`double`	`getMinimumGap()` Returns the minimum gap between two labels on the same path.
`boolean`	`isReusePreviousLocations()` Returns if the algorithm tries to reuse the previous label location.
`void`	`setLabelPriorityProvider(ILcdGXYMultiLabelPriorityProvider aLabelPriorityProvider)` Sets the label placing priority provider, specifying the priority for individual labels.
`void`	`setMinimumGap(double aMinimumGap)` Sets the minimum gap between two labels on the same path.
`void`	`setReusePreviousLocations(boolean aReusePreviousLocations)` Sets if the algorithm tries to reuse the previous label location.

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 Detail
  - TLcdGXYCurvedPathLabelingAlgorithm
```
public TLcdGXYCurvedPathLabelingAlgorithm(ILcdGXYLabelPainterProvider aGXYCurvedPathLabelPainterProvider)
```
    Creates a new TLcdGXYCurvedPathLabelingAlgorithm which uses the given ILcdGXYLabelPainterProvider to retrieve a TLcdGXYCurvedPathLabelPainter. This label painter can then be used to retrieve the bounds of a label.
    
    Parameters:
    
    aGXYCurvedPathLabelPainterProvider - a label painter provider which should return TLcdGXYCurvedPathLabelPainters.
- Method Detail
  - getMinimumGap
```
public double getMinimumGap()
```
    Returns the minimum gap between two labels on the same path.
    
    Returns:
    
    the minimum gap between two labels on the same path.
    
    Since:
    
    2021.1
    
    See Also:
    
    setMinimumGap(double)
  - setMinimumGap
```
public void setMinimumGap(double aMinimumGap)
```
    Sets the minimum gap between two labels on the same path. This distance is expressed in pixels and should be positive.
    The default value is 100 pixels.
    
    Parameters:
    
    aMinimumGap - the minimal gap between two labels on the same path.
    
    Since:
    
    2021.1
  - isReusePreviousLocations
```
public boolean isReusePreviousLocations()
```
    Returns if the algorithm tries to reuse the previous label location.
    
    Returns:
    
    if the algorithm tries to reuse the previous label location.
    
    See Also:
    
    setReusePreviousLocations(boolean)
  - setReusePreviousLocations
```
public void setReusePreviousLocations(boolean aReusePreviousLocations)
```
    Sets if the algorithm tries to reuse the previous label location.
    
    Parameters:
    
    aReusePreviousLocations - true if the algorithm should reuse the previous label location, and false otherwise.
    
    See Also:
    
    isReusePreviousLocations()
  - clone
```
public TLcdGXYCurvedPathLabelingAlgorithm 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
    
    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
    
    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
  - getLabelPriorityProvider
```
public ILcdGXYMultiLabelPriorityProvider getLabelPriorityProvider()
```
    Returns the label placing priority provider.
    
    Returns:
    
    the label placing priority provider.
    
    See Also:
    
    setLabelPriorityProvider(com.luciad.view.gxy.ILcdGXYMultiLabelPriorityProvider)
  - setLabelPriorityProvider
```
public void setLabelPriorityProvider(ILcdGXYMultiLabelPriorityProvider aLabelPriorityProvider)
```
    Sets the label placing priority provider, specifying the priority for individual labels. This priority provider specifies the order in which labels are placed. In the event labels overlap, those with higher priority are painted on top of labels with lower priority. So lower priority labels are the first candidates if labels need to be obscured.
    When no label priority provider is set, no label priorities are set.
    The priority provider is used to sort the list of labels before their placements are computed.
    
    Parameters:
    
    aLabelPriorityProvider - The priority provider to set.

LuciadLightspeedClass TLcdGXYCurvedPathLabelingAlgorithm

Constructor Summary

Method Summary

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

Methods inherited from class java.lang.Object

Constructor Detail

TLcdGXYCurvedPathLabelingAlgorithm

Method Detail

getMinimumGap

setMinimumGap

isReusePreviousLocations

setReusePreviousLocations

clone

collectLabelInfo

createLabelIterator

createLabelPlacementIterator

createLabelPlacementEvaluator

getLabelPriorityProvider

setLabelPriorityProvider