org.deegree_impl.graphics.optimizers
Class LabelOptimizer

java.lang.Object
  org.deegree_impl.graphics.optimizers.AbstractOptimizer
      org.deegree_impl.graphics.optimizers.LabelOptimizer

All Implemented Interfaces:

Optimizer

public class LabelOptimizer

extends AbstractOptimizer

Selects optimized Labels (graphical representations generated from LabelDisplayElements) that have a minimimal amount of overlapping.

The labeling and optimization approach uses ideas from papers by Ingo Petzold on automated label placement.

TODO: The handling of rotated labels is currently broken. Don't use rotated LabelDisplayElements with this optimizer at the moment!

Version:

$Revision: 1.8 $ $Date: 2004/03/12 15:56:47 $

Author:

Markus Schneider

Field Summary

private boolean[][]	candidates
private java.util.ArrayList	choices
private java.util.ArrayList	displayElements

Fields inherited from class org.deegree_impl.graphics.optimizers.AbstractOptimizer

mapView, themes

Constructor Summary

LabelOptimizer()
Creates a new instance of LabelOptimizer.

LabelOptimizer(Theme[] themes)
Creates a new instance of LabelOptimizer for the given Themes.

Method Summary

void	addTheme(Theme theme) Adds a Theme that the Optimizer should consider.
private void	anneal() Performs the "Simulated Annealing" for the LabelChoices.
private void	buildCollisionMatrix() Builds the collision matrix for all LabelChoices.
private double	objectiveFunction() Calculates a quality value for the currently selected combination of Labels.
void	optimize(java.awt.Graphics2D g) Finds optimized Label representations for the registered LabelDisplayElements.

Methods inherited from class org.deegree_impl.graphics.optimizers.AbstractOptimizer

setMapView

Methods inherited from class java.lang.Object

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

Field Detail

displayElements

private java.util.ArrayList displayElements

choices

private java.util.ArrayList choices

candidates

private boolean[][] candidates

Constructor Detail

LabelOptimizer

public LabelOptimizer()

Creates a new instance of LabelOptimizer.

LabelOptimizer

public LabelOptimizer(Theme[] themes)

Creates a new instance of LabelOptimizer for the given Themes.

Parameters:

themes -

Method Detail

addTheme

public void addTheme(Theme theme)

Adds a Theme that the Optimizer should consider.

Specified by:

addTheme in interface Optimizer

Overrides:

addTheme in class AbstractOptimizer

Parameters:

theme -

optimize

public void optimize(java.awt.Graphics2D g)

Finds optimized Label representations for the registered LabelDisplayElements.

Specified by:

optimize in interface Optimizer

Specified by:

optimize in class AbstractOptimizer

Parameters:

g -

buildCollisionMatrix

private void buildCollisionMatrix()

Builds the collision matrix for all LabelChoices.

anneal

private void anneal()

Performs the "Simulated Annealing" for the LabelChoices.

objectiveFunction

private double objectiveFunction()

Calculates a quality value for the currently selected combination of Labels.

Returns: