Pathfinding function crashes Unity?

Questions & Answers
1

Hey, I’ve been trying to add this pathfinding function to my program, but when I run it, it just crashes. I’ve read other threads and this might be an infinite loop, but I don’t see where it would be other than the recursion area (and it shouldn’t break there because of the if-statement checking if it’s out of bounds).

public void SetPath(Vector3 pos, Vector3 goal, Queue<Vector3> p, List<Vector3> visited, int cost) {

        Debug.Log("checking " + pos);
        
        //method which checks if the target tile is outside of the map
        if (core.OutOfBounds((int)goal.x, (int)goal.z))
            Debug.LogError("target tile " + goal + " is out of bounds!");

        //if the current position isn't out of bounds and hasn't been visited
        else if (!core.OutOfBounds((int)pos.x, (int)pos.z) && !visited.Contains(pos)) {

            Debug.Log("pos is within the limits of the map");

            //add tile to the visited list and path queue
            visited.Add(pos);
            p.Enqueue(pos);

            //add tile movement cost to total path cost
            cost += core.TileCost((int)pos.x, (int)pos.z);

            //if the current position is the target tile and the path is shorter than the current one
            if (pos == goal && cost < shortestPath) {
                Debug.Log("pos is the target tile");
                shortestPath = cost;
                path = p;
            }

            //else, check tiles around
            else {

                SetPath(new Vector3(pos.x + 1, 0, pos.z), goal, p, visited, cost);

                SetPath(new Vector3(pos.x, 0, pos.z + 1), goal, p, visited, cost);

                SetPath(new Vector3(pos.x - 1, 0, pos.z), goal, p, visited, cost);

                SetPath(new Vector3(pos.x, 0, pos.z - 1), goal, p, visited, cost);

            }
        }
    }
2

Your problem is that every time you SetPath in the new directions, and from there branch it again, and again, and again, each direction doesn’t know about the “visited” list that you’ve filled in the other directions, which means that your program never knows that you’ve actually visited all positions.

You need to try each direction one at a time, and when you’re done with that direction, pass the visited list down to the next direction.