2D Tile Road Pathfinding

Thanks for the fast reply! This looks like exactly what I need, will read through the tutorial :)

Thanks for the tutorial fafase, I'm just a little stuck on how to setup the tree in this scenario.
The tiles in the grid can rotate so I would need to be able to create the parent tree at runtime. For each tile I could store which other adjacent tiles are reachable.

What I am confused about though, is can I parent tile 3 back to tile 2 in the following image, despite tile 2 being the parent of tile 3?

If not then some of the roads will be blocked in certain directions I think.

Well if the tile is rotating it might be a little different. You have your QuadInt and rotating a tile is pretty much pushing the value left or right depending on the rotation.

But I would have a script that keep track of all four adjacent tiles and which are currently children.

That is one tile has four adjacent and 0 to 4 children.

Adjacents are defined with drag and drop n the script, while children are done on Start and later on rotation (probably using an event).

Your method would rotate the tile, then considering the new QuadInt values would tell the adjacent tiles that their children list should be updated.

simple something like: for (int i = 0 ; i < adjacent.Length, i++) adjacent[i].IsChildren(quadInt[i], this);

and the method goes:

 public void IsChildren(int value , Tile tile)
 {
    if(value == 0)children.Remove(tile);
    else if (value == 1)children.Add(tile);
 }

Then you can use bfs just as is. Instead of the built-in array of the tutorial, you use a dynamic list of children.

Am I clear enough...?

 What I am confused about though, is can I parent tile 3 back to tile 2 in the following image, despite tile 2 being the parent of tile 3?

Since a is adjacent of B, then B is adjacent of A and all children updates each other.

Awesome, I think that clears it up a bit ;) Am currently in the middle of creating a method which will update adjacent and children tiles.
Think I have a better understanding of the basics of the algorithm now, might have to read the tutorial a couple more times though haha.
So essentially I just need to add any adjacent tile (which has a connecting road etc) to the children array of the current tile and do this for all the tiles in the grid.
Then just use the Bfs algorithm which will cycle through the children and find the target I set. I think :) Thanks again for the help!

Essentially, each tile has 4 adjacent that are permanent and most likely added manually via inspector. Expect for the side tiles which have only 2 or 3 adjacent tiles.

While rotating, you updated the children list which correspond to the roads.

Nonetheless, keep in mind that if a tile has a connection with the next tile, it may be that the next tile is not connected back!!!

Tile A may have a road to tile B but maybe there is no road on B, see your second tile on the first pic, it is connected to the first but the first has none, so when updating the children, you could also check if there is something on the other side which in the end would save some computation as you can discard a road with no real connection on the other tile.