Package lejos.robotics.pathfinding

Class NodePathFinder

java.lang.Object

lejos.robotics.pathfinding.NodePathFinder

All Implemented Interfaces:

PathFinder

public class NodePathFinder
extends java.lang.Object
implements PathFinder

This path finder class uses one of the common search algorithms (e.g. A*) and a navigation mesh (e.g. grid) and uses them to find a path around map geometry.

Field Summary

Fields

Modifier and Type	Field and Description
private SearchAlgorithm	alg
private java.util.ArrayList<WaypointListener>	listeners
private NavigationMesh	mesh

Constructor Summary

Constructors

Modifier	Constructor and Description
private	NodePathFinder(SearchAlgorithm alg) Instantiates a NodePathFinder object using a specified algorithm.
	NodePathFinder(SearchAlgorithm alg, NavigationMesh mesh) Instantiates a NodePathFinder object using a specified algorithm.

Method Summary

Modifier and Type	Method and Description
void	addListener(WaypointListener wpl)
Path	findRoute(Pose start, Waypoint goal)
void	setNavMesh(NavigationMesh mesh) Method for changing the navigation mesh after this has been instantiated.
void	setSearchAlgorithm(SearchAlgorithm alg) Method for changing the search algorithm after this has been instantiated.
void	startPathFinding(Pose start, Waypoint end)

Methods inherited from class java.lang.Object

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

Field Detail

listeners

private java.util.ArrayList<WaypointListener> listeners

alg

private SearchAlgorithm alg

mesh

private NavigationMesh mesh

Constructor Detail

NodePathFinder

private NodePathFinder(SearchAlgorithm alg)

Instantiates a NodePathFinder object using a specified algorithm. Ideally this class would work with self propagating nodes, but it currently is not able to.

Parameters:

alg -

NodePathFinder

public NodePathFinder(SearchAlgorithm alg,
                      NavigationMesh mesh)

Instantiates a NodePathFinder object using a specified algorithm. The supplied mesh is used to add and remove nodes (start and goal) when requesting a path.

Parameters:

alg - The search algorithm.

mesh - The navigation mesh is a set of nodes in various configurations (e.g. grid).

Method Detail

setNavMesh

public void setNavMesh(NavigationMesh mesh)

Method for changing the navigation mesh after this has been instantiated.

Parameters:

mesh -

setSearchAlgorithm

public void setSearchAlgorithm(SearchAlgorithm alg)

Method for changing the search algorithm after this has been instantiated.

Parameters:

alg -

addListener

public void addListener(WaypointListener wpl)

Specified by:

addListener in interface PathFinder

findRoute

public Path findRoute(Pose start,
                      Waypoint goal)
               throws DestinationUnreachableException

Specified by:

findRoute in interface PathFinder

Throws:

DestinationUnreachableException

startPathFinding

public void startPathFinding(Pose start,
                             Waypoint end)

Specified by:

startPathFinding in interface PathFinder