roguelike-level.js

JavaScript CommonJS module for creating a roguelike level.

The concept is simple, inspired by sliding system used by Brogue. Random rooms are generated, and slid into the level in a random direction until they collide with an existing room. Once they collide a door is generated randomly in the colliding surface. We only generate rooms on odd rows and columns so that everything fits together perfectly.

Example Level

This is a simple visual representation (generated using node-example.js). Of course you'd just want to import the main library and use it in your game.

    #########    
    #.......#    
    #.......#####
    #.......#...#
#####.......X...#
#.../.......#...#
#...####/####...#
#.<.# #...# #...#
#...# #.>.# #####
#...# #...#      
##### #####      

Example Usage

var roguelikeLevelGen = require('./roguelike-level.js');

var level = roguelikeLevelGen({
  width: 17, // Max Width of the world
  height: 11, // Max Height of the world
  retry: 100, // How many times should we try to add a room?
  special: true, // Should we generate a "special" room?
  room: {
    ideal: 5, // Give up once we get this number of rooms
    min_width: 3,
    max_width: 7,
    min_height: 3,
    max_height: 7
  }
});

console.log(level);

Example Output

A typical level takes about 3ms to generate on my laptop. YMMV.

A special room can be used for whatever you want. I like to use them for shops and hidden rooms (you'll know when a door is special, too).

The world attribute is entirely optional for you to use. All the data within it can be recreated using the other attributes.

World Matrix Cell Types

TYPE	ID
VOID	0
FLOOR	1
WALL	2
DOOR	3
SPECIAL DOOR	4
ENTER	5
EXIT	6

Output JSON

{
    "width": 17,
    "height": 11,
    "enter": {
        "room_id": 1,
        "x": 2,
        "y": 7
    },
    "exit": {
        "room_id": 2,
        "x": 8,
        "y": 8
    },
    "door_count": 3,
    "doors": {
        "0": {
            "id": 0,
            "rooms": [ 0, 1 ],
            "special": false,
            "x": 4,
            "y": 5
        },
        "1": {
            "id": 1,
            "rooms": [ 0, 2 ],
            "special": false,
            "x": 8,
            "y": 6
        },
        "2": {
            "id": 2,
            "rooms": [ 0, 3 ],
            "special": true,
            "x": 12,
            "y": 4
        }
    },
    "room_count": 4,
    "rooms": {
        "0": {
            "doors": [ 0, 1, 2 ],
            "height": 5,
            "id": 0,
            "left": 5,
            "neighbors": [ 1, 2, 3 ],
            "special": false,
            "top": 1,
            "width": 7
        },
        "1": {
            "doors": [ 0 ],
            "height": 5,
            "id": 1,
            "left": 1,
            "neighbors": [ 0 ],
            "special": false,
            "top": 5,
            "width": 3
        },
        "2": {
            "doors": [ 1 ],
            "height": 3,
            "id": 2,
            "left": 7,
            "neighbors": [ 0 ],
            "special": false,
            "top": 7,
            "width": 3
        },
        "3": {
            "doors": [ 2 ],
            "height": 5,
            "id": 3,
            "left": 13,
            "neighbors": [ 0 ],
            "special": true,
            "top": 3,
            "width": 3
        }
    },
    "walls": [
      [4, 0],
      [4, 1],
      [4, 2],
      [10, 10]
    ],
    "world": [
        [ 0, 0, 0, 0, 2, 2, 2, 2, 2, 2, 2, 2, 2, 0, 0, 0, 0 ],
        [ 0, 0, 0, 0, 2, 1, 1, 1, 1, 1, 1, 1, 2, 0, 0, 0, 0 ],
        [ 0, 0, 0, 0, 2, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2 ],
        [ 0, 0, 0, 0, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2 ],
        [ 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 4, 1, 1, 1, 2 ],
        [ 2, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2 ],
        [ 2, 1, 1, 1, 2, 2, 2, 2, 3, 2, 2, 2, 2, 1, 1, 1, 2 ],
        [ 2, 1, 5, 1, 2, 0, 2, 1, 1, 1, 2, 0, 2, 1, 1, 1, 2 ],
        [ 2, 1, 1, 1, 2, 0, 2, 1, 6, 1, 2, 0, 2, 2, 2, 2, 2 ],
        [ 2, 1, 1, 1, 2, 0, 2, 1, 1, 1, 2, 0, 0, 0, 0, 0, 0 ],
        [ 2, 2, 2, 2, 2, 0, 2, 2, 2, 2, 2, 0, 0, 0, 0, 0, 0 ]
    ]
}

(Walls output is truncated)

Caveats

• Rooms must be odd sized, and at least 3 units wide/tall
• World should likewise be odd sized
• Weird things will happen if you try to generate rooms larger than the world

TODO

• Generate "interesting" rooms, e.g. with patterns of pillars
• Randomly generate doors between rooms which happen to be touching but not slid together
• Crop unused rows/columns (hence we provide max width, not width, during generation)
• Generate hallways between non-touching rooms, complete with doors
• Generate rooms which aren't rectangular (round, blobs)
• Calculate the distance of every room from entrance/exit
• Generate special terrain types, e.g. large chasms or lakes