corridors between rooms not generating; dungeon generator

Question

So i'm following this tutorial http://www.rombdn.com/blog/2018/01/12/random-dungeon-bsp-unity/ to make a randomly generated dungeon. everything works fine, until it reaches the bit where the corridors are supposed to be generated. there are no error messages. But, i'm not even getting the Debug.log messages, which means it's not seeing the CreateCorridorBetween void at all. I hope it's some sort of stupid mistake that I've missed somehow, because my brain is pretty much fried at this point. here's my script:

public class BoardManager : MonoBehaviour {
public GameObject floorTile;
public GameObject corridorTile;

public int boardRows, boardColumns;
public int minRoomSize, maxRoomSize;

private GameObject[,] boardPositionsFloor;

public class SubDungeon {

    public SubDungeon left, right;
    public Rect rect;
    public Rect room = new Rect(-1,-1, 0, 0); // i.e null
    public int debugId;

    private static int debugCounter = 0;

    public List<Rect> corridors = new List<Rect>();

    public SubDungeon(Rect mrect) {
        rect = mrect;
        debugId = debugCounter;
        debugCounter++;
    }

    public bool IAmLeaf() {
        return left == null && right == null;
    }

    public bool Split(int minRoomSize, int maxRoomSize) {
        if (!IAmLeaf()) {
            return false;
        }

        // choose a vertical or horizontal split depending on the proportions
        // i.e. if too wide split vertically, or too long horizontally,
        // or if nearly square choose vertical or horizontal at random
        bool splitH;
        if (rect.width / rect.height >= 1.25) {
            splitH = false;
        } else if (rect.height / rect.width >= 1.25) {
            splitH = true;
        } else {
            splitH = Random.Range (0.0f, 1.0f) > 0.5;
        }

        if (Mathf.Min(rect.height, rect.width) / 2 < minRoomSize) {
            Debug.Log ("Sub-dungeon " + debugId + " will be a leaf");
            return false;
        }

        if (splitH) {
            // split so that the resulting sub-dungeons widths are not too small
            // (since we are splitting horizontally)
            int split = Random.Range (minRoomSize, (int)(rect.width - minRoomSize));

            left = new SubDungeon (new Rect (rect.x, rect.y, rect.width, split));
            right = new SubDungeon (
                new Rect (rect.x, rect.y + split, rect.width, rect.height - split));
        }
        else {
            int split = Random.Range (minRoomSize, (int)(rect.height - minRoomSize));

            left = new SubDungeon (new Rect (rect.x, rect.y, split, rect.height));
            right = new SubDungeon (
                new Rect (rect.x + split, rect.y, rect.width - split, rect.height));
        }

        return true;
    }

    public void CreateRoom() {
        if (left != null) {
            left.CreateRoom ();
        }
        if (right != null) {
            right.CreateRoom ();
        }
        if (IAmLeaf()) {
            int roomWidth = (int)Random.Range (rect.width / 2, rect.width - 2);
            int roomHeight = (int)Random.Range (rect.height / 2, rect.height - 2);
            int roomX = (int)Random.Range (1, rect.width - roomWidth - 1);
            int roomY = (int)Random.Range (1, rect.height - roomHeight - 1);

            // room position will be absolute in the board, not relative to the sub-dungeon
            room = new Rect (rect.x + roomX, rect.y + roomY, roomWidth, roomHeight);
            Debug.Log ("Created room " + room + " in sub-dungeon " + debugId + " " + rect);
        }
    }

    public Rect GetRoom() {
        if (IAmLeaf()) {
            return room;
        }
        if (left != null) {
            Rect lroom = left.GetRoom ();
            if (lroom.x != -1) {
                return lroom;
            }
        }
        if (right != null) {
            Rect rroom = right.GetRoom ();
            if (rroom.x != -1) {
                return rroom;
            }
        }

        // workaround non nullable structs
        return new Rect (-1, -1, 0, 0);
    }

    public void CreateCorridorBetween(SubDungeon left, SubDungeon right) {
        Rect lroom = left.GetRoom ();
        Rect rroom = right.GetRoom ();

        Debug.Log("Creating corridor(s) between " + left.debugId + "(" + lroom + ") and " + right.debugId + " (" + rroom + ")");

        // attach the corridor to a random point in each room
        Vector2 lpoint = new Vector2 ((int)Random.Range (lroom.x + 1, lroom.xMax - 1), (int)Random.Range (lroom.y + 1, lroom.yMax - 1));
        Vector2 rpoint = new Vector2 ((int)Random.Range (rroom.x + 1, rroom.xMax - 1), (int)Random.Range (rroom.y + 1, rroom.yMax - 1));

        // always be sure that left point is on the left to simplify the code
        if (lpoint.x > rpoint.x) {
            Vector2 temp = lpoint;
            lpoint = rpoint;
            rpoint = temp;
        }

        int w = (int)(lpoint.x - rpoint.x);
        int h = (int)(lpoint.y - rpoint.y);

        Debug.Log ("lpoint: " + lpoint + ", rpoint: " + rpoint + ", w: " + w + ", h: " + h);

        // if the points are not aligned horizontally
        if (w != 0) {
            // choose at random to go horizontal then vertical or the opposite
            if (Random.Range (0, 1) > 2) {
                // add a corridor to the right
                corridors.Add (new Rect (lpoint.x, lpoint.y, Mathf.Abs (w) + 1, 1));

                // if left point is below right point go up
                // otherwise go down
                if (h < 0) {
                    corridors.Add (new Rect (rpoint.x, lpoint.y, 1, Mathf.Abs (h)));
                } else {
                    corridors.Add (new Rect (rpoint.x, lpoint.y, 1, -Mathf.Abs (h)));
                }
            } else {
                // go up or down
                if (h < 0) {
                    corridors.Add (new Rect (lpoint.x, lpoint.y, 1, Mathf.Abs (h)));
                } else {
                    corridors.Add (new Rect (lpoint.x, rpoint.y, 1, Mathf.Abs (h)));
                }

                // then go right
                corridors.Add (new Rect (lpoint.x, rpoint.y, Mathf.Abs (w) + 1, 1));
            }
        } else {
            // if the points are aligned horizontally
            // go up or down depending on the positions
            if (h < 0) {
                corridors.Add (new Rect ((int)lpoint.x, (int)lpoint.y, 1, Mathf.Abs (h)));
            } else {
                corridors.Add (new Rect ((int)rpoint.x, (int)rpoint.y, 1, Mathf.Abs (h)));
            }
        }

        Debug.Log ("Corridors: ");
        foreach (Rect corridor in corridors) {
            Debug.Log ("corridor: " + corridor);
        }
    }
}

public void CreateBSP(SubDungeon subDungeon) {
    Debug.Log ("Splitting sub-dungeon " + subDungeon.debugId + ": " + subDungeon.rect);
    if (subDungeon.IAmLeaf()) {
        // if the sub-dungeon is too large
        if (subDungeon.rect.width > maxRoomSize
            || subDungeon.rect.height > maxRoomSize
            || Random.Range(0.0f,1.0f) > 0.25) {

            if (subDungeon.Split (minRoomSize, maxRoomSize)) {
                Debug.Log ("Splitted sub-dungeon " + subDungeon.debugId + " in "
                    + subDungeon.left.debugId + ": " + subDungeon.left.rect + ", "
                    + subDungeon.right.debugId + ": " + subDungeon.right.rect);

                CreateBSP(subDungeon.left);
                CreateBSP(subDungeon.right);
            }
        }
    }
}
public void DrawRooms(SubDungeon subDungeon) {
    if (subDungeon == null) {
        return;
    }
    if (subDungeon.IAmLeaf()) {
        for (int i = (int)subDungeon.room.x; i < subDungeon.room.xMax; i++) {
            for (int j = (int)subDungeon.room.y; j < subDungeon.room.yMax; j++) {
                GameObject instance = Instantiate (floorTile, new Vector3 (i, j, 0f), Quaternion.identity) as GameObject;
                instance.transform.SetParent (transform);
                boardPositionsFloor [i, j] = instance;
            }
        }
    } else {
        DrawRooms (subDungeon.left);
        DrawRooms (subDungeon.right);
    }
}

void DrawCorridors(SubDungeon subDungeon) {
    if (subDungeon == null) {
        return;
    }

    DrawCorridors (subDungeon.left);
    DrawCorridors (subDungeon.right);

    foreach (Rect corridor in subDungeon.corridors) {
        for (int i = (int)corridor.x; i < corridor.xMax; i++) {
            for (int j = (int)corridor.y; j < corridor.yMax; j++) {
                if (boardPositionsFloor [i, j] == null) {
                    GameObject instance = Instantiate (corridorTile, new Vector3 (i, j, 0f), Quaternion.identity) as GameObject;
                    instance.transform.SetParent (transform);
                    boardPositionsFloor [i, j] = instance;
                }
            }
        }
    }
}

void Start () {
    SubDungeon rootSubDungeon = new SubDungeon (new Rect (0, 0, boardRows, boardColumns));
    CreateBSP (rootSubDungeon);
    rootSubDungeon.CreateRoom ();

    boardPositionsFloor = new GameObject[boardRows, boardColumns];
    DrawCorridors (rootSubDungeon);
    DrawRooms (rootSubDungeon);
}
}

I can't seem to figure out what's wrong, I'm doing as the tutorial says, step by step.

Answer 1

Probably due to a typo from part of the author of the tutorial, the original code is missing a call to CreateCorridorBetween.

To fix that add the call in CreateRoom, like this:

public void CreateRoom()
{
    if (left != null)
    {
        left.CreateRoom();
    }
    if (right != null)
    {
        right.CreateRoom();
    }
    if (IAmLeaf())
    {
        int roomWidth = (int)Random.Range(rect.width / 2, rect.width - 2);
        int roomHeight = (int)Random.Range(rect.height / 2, rect.height - 2);
        int roomX = (int)Random.Range(1, rect.width - roomWidth - 1);
        int roomY = (int)Random.Range(1, rect.height - roomHeight - 1);

        // room position will be absolute in the board, not relative to the sub-dungeon
        room = new Rect(rect.x + roomX, rect.y + roomY, roomWidth, roomHeight);
        Debug.Log("Created room " + room + " in sub-dungeon " + debugId + " " + rect);
    }

    if (right != null && left != null)
        CreateCorridorBetween(left, right);
}

By adding the call there, you don't need to re-walk the sub dungeons with a loop as I originally suggested in my previous comment.

The if is more for safety than for real need, as I didn't try to gain a full understanding of the code, only what was need to apply a quick fix. But at leas I did confirm, to save time for the reader, that my code doesn't create duplicated tiles, you can verify this by inspecting the scene hierarchy in Unity Editor during execution of the game.

Note: if you are getting the corridor tiles over the floor tiles (corridors drawn over rooms) simply do this to place the call to DrawRooms before call to DrawCorridors.

void Start()
{
    SubDungeon rootSubDungeon = new SubDungeon(new Rect(0, 0, boardRows, boardColumns));
    CreateBSP(rootSubDungeon);
    rootSubDungeon.CreateRoom();

    boardPositionsFloor = new GameObject[boardRows, boardColumns];
    DrawRooms(rootSubDungeon);
    DrawCorridors(rootSubDungeon);
}

Note that my Start method differs of yours in the order of DrawRooms and DrawCorridors.

There is a lot of room for improvement, have fun with procedural generation.

Tiles from opengameart.org: https://opengameart.org/node/20710 and https://opengameart.org/content/seamless-concrete-floor-tile