//Finds a specific node in the given list
public visitedNode searchListForNode(List <visitedNode> list, Vector2 x)
{
visitedNode z = new visitedNode(GetCoordinates(), GetCoordinates());
for (int i = 0; i < list.Count; i++)
{
if (list[i].visit == x)
{
return(list[i]);
}
}
return(z);
}
public Vector2 backTrack(List <visitedNode> list)
{
//The player coordinates are the end of the path we want, so find them in the list
visitedNode x = searchListForNode(list, this.gameManager.GetPlayer().GetCoordinates());
//While the current visitedNode isn't one move away from our starting point, backtrack
while (x.visitedBy != GetCoordinates())
{
x = searchListForNode(list, x.visitedBy);
}
//we are now on the tile that is one move away from the enemy on the shortest path to the player, return it if it is not the players coords
if (x.visit.Equals(this.gameManager.GetPlayer().GetCoordinates()))
{
return(Vector2.zero);
}
return(x.visit);
}
//Locates the shortest path between the player and the enemy
public Vector2 shortestPath()
{
bool pathFound = false;
//list that holds all the visitedNode structs (tile currently being visited, which tile visited it)
List <visitedNode> visited = new List <visitedNode>();
//Queue to hold tiles that need to be searched
Queue <Vector2> searchingQueue = new Queue <Vector2>();
//Add enemy tile to the queue to start the process
searchingQueue.Enqueue(GetCoordinates());
//Add current game tile to the list of visited nodes to make sure the enemy's tile isn't processed again
visitedNode starter = new visitedNode(GetCoordinates(), GetCoordinates());
visited.Add(starter);
while (pathFound == false)
{
//Grab next game tile to be processed
if (searchingQueue.Count == 0)
{
return(Vector2.zero);
}
Vector2 current = searchingQueue.Dequeue();
//Check to see if the current vector is the player's tile
if (current.Equals(this.gameManager.GetPlayer().GetCoordinates()))
{
pathFound = true;
}
//if not, Grab all neighboring tiles
GameTile up = gameManager.GetTile(current + Vector2.up);
GameTile down = gameManager.GetTile(current + Vector2.down);
GameTile right = gameManager.GetTile(current + Vector2.right);
GameTile left = gameManager.GetTile(current + Vector2.left);
//For each neighbor, check to see if it can be walked on, and make sure it hasn't already been visited
//via the searchList function
if (up != null && up.isWalkable == true)
{
if (searchList(visited, current + Vector2.up) == false)
{
visitedNode z = new visitedNode(current + Vector2.up, current);
visited.Add(z);
searchingQueue.Enqueue(current + Vector2.up);
}
}
if (down != null && down.isWalkable == true)
{
if (searchList(visited, current + Vector2.down) == false)
{
visitedNode z = new visitedNode(current + Vector2.down, current);
visited.Add(z);
searchingQueue.Enqueue(current + Vector2.down);
}
}
if (right != null && right.isWalkable == true)
{
if (searchList(visited, current + Vector2.right) == false)
{
visitedNode z = new visitedNode(current + Vector2.right, current);
visited.Add(z);
searchingQueue.Enqueue(current + Vector2.right);
}
}
if (left != null && left.isWalkable == true)
{
if (searchList(visited, current + Vector2.left) == false)
{
visitedNode z = new visitedNode(current + Vector2.left, current);
visited.Add(z);
searchingQueue.Enqueue(current + Vector2.left);
}
}
}
//The path has been found, now backtrack through the list to find what the next move is
return(backTrack(visited));
}
