private void FindPath(Vector3 startPosition, Vector3 targetPosition)
    {
        Stopwatch sw = new Stopwatch();

        sw.Start();

        Node startNode  = aGrid.NodeFromWorldPoint(startPosition);
        Node targetNode = aGrid.NodeFromWorldPoint(targetPosition);

        List <Node>    openSet   = new List <Node>();
        HashSet <Node> closedSet = new HashSet <Node>();

        openSet.Add(startNode);

        while (openSet.Count > 0)
        {
            Node currentNode = openSet[0];
            for (int i = 1; i < openSet.Count; i++)
            {
                if (openSet[i].fCost < currentNode.fCost ||
                    openSet[i].fCost == currentNode.fCost && openSet[i].hCost < currentNode.hCost)
                {
                    currentNode = openSet[i];
                }
            }

            openSet.Remove(currentNode);
            closedSet.Add(currentNode);

            // The target has been found, so exit out of the loop
            if (currentNode == targetNode)
            {
                sw.Stop();
                print("Path found: " + sw.ElapsedMilliseconds + " ms");
                RetracePath(startNode, targetNode);
                return;
            }

            foreach (Node neighbor in aGrid.GetNeighbors(currentNode))
            {
                if (!neighbor.walkable || closedSet.Contains(neighbor))
                {
                    continue;
                }

                int newMovementCostToNeighbor = currentNode.gCost + GetDistance(currentNode, neighbor);
                if (newMovementCostToNeighbor < neighbor.gCost || !openSet.Contains(neighbor))
                {
                    neighbor.gCost  = newMovementCostToNeighbor;
                    neighbor.hCost  = GetDistance(neighbor, targetNode);
                    neighbor.parent = currentNode;

                    if (!openSet.Contains(neighbor))
                    {
                        openSet.Add(neighbor);
                    }
                }
            }
        }
    }
    IEnumerator FindPath(Vector3 startPosition, Vector3 targetPosition)
    {
        Stopwatch sw = new Stopwatch();

        sw.Start();

        Vector3[] waypoints   = new Vector3[0];
        bool      pathSuccess = false;

        Node startNode  = aGrid.NodeFromWorldPoint(startPosition);
        Node targetNode = aGrid.NodeFromWorldPoint(targetPosition);

        if (startNode.walkable && targetNode.walkable)
        {
            Heap <Node>    openSet   = new Heap <Node>(aGrid.MaxSize);
            HashSet <Node> closedSet = new HashSet <Node>();
            openSet.Add(startNode);

            while (openSet.Count > 0)
            {
                Node currentNode = openSet.RemoveFirst();
                closedSet.Add(currentNode);

                // The target has been found, so exit out of the loop
                if (currentNode == targetNode)
                {
                    sw.Stop();
                    //print("Path found: " + sw.ElapsedMilliseconds + " ms");
                    pathSuccess = true;
                    break;
                }

                foreach (Node neighbor in aGrid.GetNeighbors(currentNode))
                {
                    if (!neighbor.walkable || closedSet.Contains(neighbor))
                    {
                        continue;
                    }

                    int newMovementCostToNeighbor = currentNode.gCost + GetDistance(currentNode, neighbor)
                                                    + neighbor.movementPenalty;
                    if (newMovementCostToNeighbor < neighbor.gCost || !openSet.Contains(neighbor))
                    {
                        neighbor.gCost  = newMovementCostToNeighbor;
                        neighbor.hCost  = GetDistance(neighbor, targetNode);
                        neighbor.parent = currentNode;

                        if (!openSet.Contains(neighbor))
                        {
                            openSet.Add(neighbor);
                        }
                        else
                        {
                            openSet.UpdateItem(neighbor);
                        }
                    }
                }
            }
        }

        yield return(null);

        if (pathSuccess)
        {
            waypoints = RetracePath(startNode, targetNode);
        }
        requestManager.FinishedProcessingPath(waypoints, pathSuccess);
        pathID++; // FOR DEBUGGING ONLY
    }