Obstacles

A grid without any obstacles is boring. Let us create a grid with obstacles:

var walkabilityMatrix = [[0, 0, 0, 0, 0],
                         [1, 1, 1, 1, 0],
                         [0, 0, 0, 0, 0],
                         [0, 1, 1, 1, 1],
                         [0, 0, 0, 0, 0],
                         [1, 1, 1, 1, 0],
                         [0, 0, 0, 0, 0]];
var grid = new PF.Grid(matrix);

The walkabilityMatrix defines which cells are walkable and which have obstacles. Ones are obstacles and zeroes are walkable. Alternatively, you can also set the obstacles on the grid by calling the setWalkableAt function:

var grid = new PF.Grid(5, 7);
grid.setWalkableAt(0, 1, false);
grid.setWalkableAt(1, 1, false);
grid.setWalkableAt(2, 1, false);
...

After setting the obstacles the grid should look like this.

Let us find a path now.

var finder = new PF.AStarFinder();
var path = finder.findPath(0, 0, 4, 6, grid);

PathFinding.js will find the following path:

Notice how the path moves diagonally where it can, thus making it shorter. This may not be always desirable and you may want to create a path without any diagonal movement. Read the next section to find out how to achieve that.