Pathfindingjs

Install with npm install gjuchault/pathfindingjs --save

Basic usage

var grid = [
    [ 0, 1, 0, 0, 0 ],
    [ 0, 0, 1, 0, 0 ],
    [ 0, 0, 0, 1, 0 ],
    [ 0, 1, 1, 1, 0 ],
    [ 0, 0, 0, 0, 0 ]
];

var Pathfinding = require('pathfindingjs');

var finder = new Pathfinding(grid);
var path = finder
    .setFrom(2, 0)
    .setTo(2, 2)
    .find();
console.log(path);

Note : if you try to reach the origin point (from (2, 0) to (2, 0)), find will return true

Walker size

The walker size is a number representing the width taken by the walker around its starting point. That means that a basic walker has a walker size of 1 (O being the walker) :

. . . .
. O . .
. . . .
. . . .

And a walker with a size of two is like this (O and x being the walker) :

x x x .
x O x .
x x x .
. . . .

var grid = [
    [ 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0 ],
    [ 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0 ],
    [ 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0 ],
    [ 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0 ],
    [ 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0 ],
    [ 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0 ],
    [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0 ],
    [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0 ],
    [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0 ],
    [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0 ],
    [ 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0 ],
    [ 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0 ],
    [ 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0 ],
    [ 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0 ],
    [ 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0 ]
];

var Pathfinding = require('.');

var finder = new Pathfinding(grid, 2);
var path = finder
    .setFrom(1, 1)
    .setTo(13, 2)
    .find();

console.log(path);

Chaining

After calling find, the origin is set to the target point, and you may call setTo and find again

var grid = [
    [ 0, 1, 0, 0, 0 ],
    [ 0, 0, 1, 0, 0 ],
    [ 0, 0, 0, 1, 0 ],
    [ 0, 1, 1, 1, 0 ],
    [ 0, 0, 0, 0, 0 ]
];

var Pathfinding = require('pathfindingjs');

var finder = new Pathfinding(grid);
var path = finder
    .setFrom(2, 0)
    .setTo(2, 2)
    .find();
console.log(path);

var returnPath = finder
    .setTo(2, 0)
    .find();
console.log(returnPath);

require('assert').deepEqual(path.reverse(), returnPath);

Path length

If you want to compare two smoothen paths, you may want to use Pathfinding.getFullLength(path). It will return the sum of Manhattan distances between each point. This is useful only on smoothen paths.