com.badlogic.gdx.ai.pfa

Class HierarchicalPathFinder<N>

java.lang.Object

com.badlogic.gdx.ai.pfa.HierarchicalPathFinder<N>

Type Parameters:

N - Type of node

All Implemented Interfaces:

PathFinder<N>

public class HierarchicalPathFinder<N>
extends java.lang.Object
implements PathFinder<N>

A HierarchicalPathFinder can find a path in an arbitrary HierarchicalGraph using the given PathFinder, known as level path finder, on each level of the hierarchy.

Pathfinding on a hierarchical graph applies the level path finder algorithm several times, starting at a high level of the hierarchy and working down. The results at high levels are used to limit the work it needs to do at lower levels.

Note that the hierarchical path finder calls the HierarchicalGraph.setLevel(int) method to switch the graph into a particular level. All future calls to the getConnections method of the hierarchical graph then act as if the graph was just a simple, non-hierarchical graph at that level. This way, the level path finder has no way of telling that it is working with a hierarchical graph and it doesn't need to, meaning that you can use any path finder implementation for the level path finder.

Field Summary

Fields

Modifier and Type	Field and Description
static boolean	DEBUG

Constructor Summary

Constructors

Constructor and Description
HierarchicalPathFinder(HierarchicalGraph<N> graph, PathFinder<N> levelPathFinder)

Method Summary

Modifier and Type	Method and Description
boolean	search(PathFinderRequest<N> request, long timeToRun) Performs an interruptible search, trying to find a path made up of nodes from the start node to the goal node attempting to honor costs provided by the graph.
boolean	searchConnectionPath(N startNode, N endNode, Heuristic<N> heuristic, GraphPath<Connection<N>> outPath) Performs a non-interruptible search, trying to find a path made up of connections from the start node to the goal node attempting to honor costs provided by the graph.
boolean	searchNodePath(N startNode, N endNode, Heuristic<N> heuristic, GraphPath<N> outPath) Performs a non-interruptible search, trying to find a path made up of nodes from the start node to the goal node attempting to honor costs provided by the graph.

Methods inherited from class java.lang.Object

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

Field Detail

DEBUG

public static boolean DEBUG

Constructor Detail

HierarchicalPathFinder

public HierarchicalPathFinder(HierarchicalGraph<N> graph,
                              PathFinder<N> levelPathFinder)

Method Detail

searchNodePath

public boolean searchNodePath(N startNode,
                              N endNode,
                              Heuristic<N> heuristic,
                              GraphPath<N> outPath)

Description copied from interface: PathFinder

Performs a non-interruptible search, trying to find a path made up of nodes from the start node to the goal node attempting to honor costs provided by the graph.

Specified by:

searchNodePath in interface PathFinder<N>

Parameters:

startNode - the start node

endNode - the end node

heuristic - the heuristic function

outPath - the output path that will only be filled if a path is found, otherwise it won't get touched.

Returns:

true if a path was found; false otherwise.

searchConnectionPath

public boolean searchConnectionPath(N startNode,
                                    N endNode,
                                    Heuristic<N> heuristic,
                                    GraphPath<Connection<N>> outPath)

Description copied from interface: PathFinder

Performs a non-interruptible search, trying to find a path made up of connections from the start node to the goal node attempting to honor costs provided by the graph.

Specified by:

searchConnectionPath in interface PathFinder<N>

Parameters:

startNode - the start node

endNode - the end node

heuristic - the heuristic function

outPath - the output path that will only be filled if a path is found, otherwise it won't get touched.

Returns:

true if a path was found; false otherwise.

search

public boolean search(PathFinderRequest<N> request,
                      long timeToRun)

Description copied from interface: PathFinder

Performs an interruptible search, trying to find a path made up of nodes from the start node to the goal node attempting to honor costs provided by the graph.

Specified by:

search in interface PathFinder<N>

Parameters:

request - the pathfinding request

timeToRun - the time in nanoseconds that can be used to advance the search

Returns:

true if the search has finished; false otherwise.