com.yworks.yfiles.graph.labelmodels

Class DefaultLabelModelParameterFinder

java.lang.Object

com.yworks.yfiles.graph.labelmodels.DefaultLabelModelParameterFinder

All Implemented Interfaces:

ILabelModelParameterFinder

public class DefaultLabelModelParameterFinder
extends Object
implements ILabelModelParameterFinder

A simple default implementation of the ILabelModelParameterFinder interface that uses the ILabelModel's own ILabelModelParameterProvider instance to find the closest match.

This implementation uses a metric to find the closest of the provided parameter candidates to the layout provided in findBestParameter(ILabel, IOrientedRectangle, Iterable).

Field Summary

Fields

Modifier and Type	Field and Description
static DefaultLabelModelParameterFinder	INSTANCE A singleton instance of this class.

Constructor Summary

Constructors

Constructor and Description
DefaultLabelModelParameterFinder()

Method Summary

Modifier and Type	Method and Description
protected double	calculateMetric(ILabel label, ILabelModelParameter layoutParameter, IOrientedRectangle layout) Calculates a metric for the given label/parameter pair and the target label layout.
protected double	distance(IOrientedRectangle rectangle1, IOrientedRectangle rectangle2) Returns the distance between two IOrientedRectangle instances.
ILabelModelParameter	findBestParameter(ILabel label, ILabelModel model, IOrientedRectangle layout) Tries to find a parameter that best matches the given layout for the provided label instance.
ILabelModelParameter	findBestParameter(ILabel label, IOrientedRectangle layout, Iterable<ILabelModelParameter> layoutParameters) Tries to find a parameter that best matches the given layout for the provided label instance among the set of given parameters.
protected Iterable<ILabelModelParameter>	getCandidateParameters(ILabel label, ILabelModel model) Retrieves an enumerator over all candidates for a given label and model.

Methods inherited from class java.lang.Object

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

Field Detail

INSTANCE

public static final DefaultLabelModelParameterFinder INSTANCE

A singleton instance of this class.

Constructor Detail

DefaultLabelModelParameterFinder

public DefaultLabelModelParameterFinder()

Method Detail

calculateMetric

protected double calculateMetric(ILabel label,
                                 ILabelModelParameter layoutParameter,
                                 IOrientedRectangle layout)

Calculates a metric for the given label/parameter pair and the target label layout.

This implementation gets the geometry from the parameter's model's ILabelModel.getGeometry(ILabel, ILabelModelParameter) method and returns the result of a call to distance(IOrientedRectangle, IOrientedRectangle).

Parameters:

label - The label to apply the parameter to.

layoutParameter - The parameter candidate.

layout - The targeted layout rectangle.

Returns:

A metric that indicates the distance between the candidate's layout and the target layout.

distance

protected final double distance(IOrientedRectangle rectangle1,
                                IOrientedRectangle rectangle2)

Returns the distance between two IOrientedRectangle instances.

The distance is calculated using the Euclidean distance between the two centers and the angular deviation between the two up vectors.

Parameters:

rectangle1 - The first geometry.

rectangle2 - The geometry to compare the first one with.

Returns:

A value indicating the distance between the two instances.

findBestParameter

public final ILabelModelParameter findBestParameter(ILabel label,
                                                    ILabelModel model,
                                                    IOrientedRectangle layout)

Tries to find a parameter that best matches the given layout for the provided label instance.

This method may not necessarily find a parameter that matches the provided layout exactly. It will first query the getCandidateParameters(ILabel, ILabelModel) parameter for an enumeration of candidates and will then find the best matching candidate using a metric calculated by calculateMetric(ILabel, ILabelModelParameter, IOrientedRectangle). If no parameter can be found this method returns the default parameter for the model.

Specified by:

findBestParameter in interface ILabelModelParameterFinder

Parameters:

label - The label to find a parameter for.

model - The model instance to use. This should be the instance this instance has been obtained from.

layout - The anticipated layout for the label.

Returns:

A non-null parameter that can be used for the label to approximate the provided layout.

findBestParameter

public final ILabelModelParameter findBestParameter(ILabel label,
                                                    IOrientedRectangle layout,
                                                    Iterable<ILabelModelParameter> layoutParameters)

Tries to find a parameter that best matches the given layout for the provided label instance among the set of given parameters.

Null may be returned if an empty enumerable is passed.

Parameters:

label - The label to find a parameter for.

layout - The anticipated layout for the label.

layoutParameters - A set of parameters to choose from.

Returns:

A parameter that can be used for the label to approximate the provided layout.

getCandidateParameters

protected Iterable<ILabelModelParameter> getCandidateParameters(ILabel label,
                                                                ILabelModel model)

Retrieves an enumerator over all candidates for a given label and model.

Parameters:

label - The label.

model - The model of the label.

Returns:

An enumerator over the candidates. The enumerator may be empty.