A simple recursive algorithm used to generate corridors and rooms inside of a grid based tile map. The core of the algorithm has been uploaded alongside a built version for demonstration purposes.

Original Build is the original version of the algorithm, to compare progress.

Model Build is the newest version of the algorithm with animated showoff.

Model Build - Realtime Generation is the newest version of the algorithm without animated showoff.

G to generate a new map

Arrow Keys to move the camera around

- and = to zoom

Numpad to select an alternate floor

The algorithm begins by checking that it is still within the bounds of the map, then checks neighboring tiles to make sure no tile types that should be avoided are nearby ( such as Rooms for Corridor tiles )

After checks are complete, the Corridor tile type is added to the current position. Tile Types are stored as an Enum in another class and only represent an arbitrary type. Many more types can be used.

The algorithm then proceeds to RNG rolls, which implies generating multiple float type numbers from 0 to 1 and checking if they are lower than the Branch, Turn, End, Room, Stairs, Model, and CSAvoid to induce their respective effects to the current process. Since we are checking if the generated number is lower, a parameter of 1 will ensure the effect happens every time.

• Branch causes the corridor to branch into a perpendicular corridor, the direction of which is determined by a boolean random roll.

• Turn converts a currently branching corridor into a single "turn" by calling return once the first branch has completed.

• End suspends the current corridor by immediately calling return.

• Room adds an entrance and calls the room generation algorithm to grow a room, the style and type of which depending on the orientation of the entrance.

• Stairs adds stairwells towards the top or bottom of the dungeon, also creating new corridors to grow a new floor.

• Model adds a pre made model by chosing randomly from the input list of models.

• CSAvoid or Corridor Self Avoid allows or disallow the corridor to connect to existing corridors.

More of those random parameters can be added to generate more desirable results.

Models have been recently added and combine the manual level design capabilities of a human to the growth of the level by randomly chosing from a set of premade tile type arrays. Those models, which can be of any size and span multiple floors, are then rotated and placed by the algorithm.

This system has recently been updated to allow Unique models or models that are limited in how often they can appear on generated maps.

Code samples for model placement, rotation and creation are included in the Source folder.

Deadends can now be found and removed using a couple algorithms, which have been added to the Source folder.

Essentially, any Corridor type tile that has less than 2 non empty immediate neighbors can be considered to be deadends. They are found and removed after the map is generated to give them a cleaner layout, as seen below.

Example 1 - Before

Example 1 - After

Example 2 - Before

Example 2 - After

Of course, it is also possible to to single passes of the find+remove algorithms to simply shorten the deadends rather than completely removing them.

Deadend removal code has been recently updated to also remove a new type of "Planar" style staircases and useless room entrances.

Post Generation Triggers have recently been added as a way to invoke generation algorithms after the main layout has been generated.

For example, a room may include an alternate exit or entrance which is not initlally connected to the rest of the layout.

PGTriggers allows the storage of which position on your map require post generation actions, which action to execute and in what orientation.

For the case of our alternate room entrance, simply adding a PGTrigger at the position of this entrance with the "Grow Corridor" behavior will start a new corridor from this point and hopefully connect that alternate entrance to another part of your layout.

PGTriggers can also be used to generate extra rooms, stairs and models.

The system has recently been updated to allow artifical inflation of the Current Count and Max Length values used to control the length of corridors, as well as placing the Ending type tile. By using an offset on those values on a corridor being generated from a trigger, the generator can be forced to place the Ending tile after a particular room.

A simple way to make more diverse layouts is to apply a scaling factor to each random roll value. The strength of this scaling factor is calculated using the distance the current floor is relative to the spawn floor.

This means that scaling factors can be used to make floors that are further away from the spawn point get increasingly chaotic and messy by scaling up the Branch parameter.

To create levels that make a bit more sense in the context of a game, some layout requirements must be put in place. Selective Layout Generation makes sure that only levels that meet those requirements are kept by the generator.

The non animated updated build shows this feature in action. In this instance, only maps that feature one Boss Room ( big yellow area ) are kept.

Since many maps must be discarded, this feature should not be abused since too complex requirement paired with a setup that produces bad maps could result in very long gen time. The maximum amount of tries should be capped for this reason.