AStarLibrary : AStar implementation in Java

This library allows to estimate shortest path on a grid, by using the A* algorithm.

Latest release

The most recent release is v0.2, released October 22, 2016

You can get the .jar here : https://github.com/Mursaat/AStarLibrary/releases/tag/v0.2

To add a dependency using Gradle:

repositories {
	jcenter()
	maven { url "https://jitpack.io" }
}
dependencies {
	compile 'com.github.mursaat:astarlibrary:v0.2'
}

Changelog

• 0.2 - Add possibility to check by flood fill if the position is reachable before performing A*

Getting started

You have to implements PathFinderMap, and the method isTraversable. Here is an example.

public class MyMap implements PathFinderMap {
	private enum CellType { GRASS, DIRT, LAVA }
	private int width;
	private int height;
    
	private CellType[][] cells;
    
	public MyMap(int width, int height) {
		this.width = width;
		this.height = height;
		cells = new CellType[width][height];
		... // Initialization
	}
    
	@Override
	boolean isTraversable(int x, int y){
		return cells[x][y] != CellType.LAVA;
	}
    
	@Override
	public int getWidth(){
		return width;
	}
    
	@Override
	public int getHeight(){
		return height;
	}
}

After that, you have to create an instance of AStarParams, and initialize it as you wish. Now, you can call AStar.findPath on your params object and get a LinkedList which contains your path.

MyMap map = new MyMap(26,11);
PathNodePosition startPos = new PathNodePosition(1,3);
PathNodePosition endPos = new PathNodePosition(8,6);
AStarParams params = new AStarParams(map, startPos, endPos);
params.setNeighborsEnumerator(NeighborsEnumerator.ORTHO_NEIGHBORS).setHeuristic(DistanceCalculator.MANHATTAN_DISTANCE)
// Perform a flood fill test to check if position is reachable ?
params.setMustCheckPosSameArea(false);

LinkedList<PathNodePosition> path = AStar.findPath(params);