Package ch.sahits.game.openpatrician.engine.sea

Class AStarHeuristicProvider

java.lang.Object

ch.sahits.game.openpatrician.engine.sea.BaseGraphCalulationService

ch.sahits.game.openpatrician.engine.sea.AStarHeuristicProvider

@Component
@Lazy
public class AStarHeuristicProvider
extends BaseGraphCalulationService

This singleton provides the heuristic for a specific map for the A* algorithm. Initially the heuristic from all nodes to all cities is calculated, based on:

• The Eucledian distance

The heuristic can also be queried if a source has it's heuristic calculated and calculate the heuristic values for that node. The heuristic may not be admissable, meaning that the value given in the heuristic for the distance between A and B may be larger than the actual distance, however the result should still be good enough.

Author:

Andi Hotz, (c) Sahits GmbH, 2015 Created on Dec 31, 2015

Field Summary

Fields inherited from class ch.sahits.game.openpatrician.engine.sea.BaseGraphCalulationService

imageService, map, pointInterner

Fields inherited from interface ch.sahits.game.graphic.image.model.MapGrid

CHECK_DISTANCE, DIAG_CHECK_DISTANCE

Constructor Summary

Constructors

Constructor	Description
AStarHeuristicProvider()

Method Summary

Modifier and Type	Method	Description
void	addSourceNodeToHeuristic(javafx.geometry.Point2D source)	Add a new target node to the heuristic.
void	addTargetNodeToHeuristic(javafx.geometry.Point2D target)	Add a new target node to the heuristic.
protected double	calculateWeight(javafx.geometry.Point2D from, javafx.geometry.Point2D to)	Calculate the weight between two nodes.
javafx.geometry.Point2D	findClosest(javafx.geometry.Point2D point)	Find the closest point in the graph for a defined point.
java.util.Map<javafx.geometry.Point2D,com.carrotsearch.hppc.ObjectDoubleMap<javafx.geometry.Point2D>>	getHeuristic()	Retrieve the heuristic map.
boolean	heuristicForSourceAvailable(javafx.geometry.Point2D source)	Check if the heuristic for a target location is calculated.
void	registerGameLoad(ch.sahits.game.openpatrician.event.GameStateChange gameStateChange)

Methods inherited from class ch.sahits.game.openpatrician.engine.sea.BaseGraphCalulationService

getPoint, getSegments, getTangentialSegments, isOnSea

Methods inherited from class java.lang.Object

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

Constructor Detail

AStarHeuristicProvider

public AStarHeuristicProvider()

Method Detail

registerGameLoad

public void registerGameLoad(ch.sahits.game.openpatrician.event.GameStateChange gameStateChange)

calculateWeight

protected double calculateWeight(javafx.geometry.Point2D from,
                                 javafx.geometry.Point2D to)

Description copied from class: BaseGraphCalulationService

Calculate the weight between two nodes.

Specified by:

calculateWeight in class BaseGraphCalulationService

Parameters:

from - source node

to - destination node

Returns:

weight of the edge from node from to to

heuristicForSourceAvailable

public boolean heuristicForSourceAvailable(javafx.geometry.Point2D source)

Check if the heuristic for a target location is calculated.

Parameters:

source - location

Returns:

true if the heuristic is present.

getHeuristic

public java.util.Map<javafx.geometry.Point2D,com.carrotsearch.hppc.ObjectDoubleMap<javafx.geometry.Point2D>> getHeuristic()

Retrieve the heuristic map. This method is blocking while the heuristic is beeing calculated to ensure there are no out of date data contained.

Returns:

Heuristic map for target locations to any location in the grid.

addTargetNodeToHeuristic

public void addTargetNodeToHeuristic(javafx.geometry.Point2D target)

Add a new target node to the heuristic.

Parameters:

target - location to be added.

addSourceNodeToHeuristic

public void addSourceNodeToHeuristic(javafx.geometry.Point2D source)

Add a new target node to the heuristic.

Parameters:

source - location to be added.

findClosest

public javafx.geometry.Point2D findClosest(javafx.geometry.Point2D point)

Find the closest point in the graph for a defined point.

Parameters:

point - for which the closest defined point should be looked up.

Returns:

closest point to point