A Swift 4.2 translation of this tutorial. When I was developing a side project, Apple's SKTileMap framework was riddled with bugs and did not cut it for me. So I wrote my own based off of the above tutorial to compensate.
Download the files "Generator.swift" and "GameScene.swift" and drop them into your .xcodeproject or simply copy/paste the code into wherever you need it. The code is formatted and commented. It has been tested and is working.
To initialize a custom map:
map = TileEngine(tileSize: CGSize(width: Int, height: Int), columns: Int, rows: Int)
Because the dungeons are procedurally generated, no two dungeons will ever generate the same.
When you implement the algorithm and build and run it, you might see a white image with a red X on it. This is because the tile definitions in the TileEngine.swift file have not been provided a texture to display.
By default, the tile map is set to a scale of 0.2 to provide an easy viewing angle. You need to go into the TileEngine.swift file and remove the line tileMap.setScale(0.2) from the bottom of the init() method.
Note: This is not a tutorial on how to make SKTileMapNodes work. This is an algorithm to generate SKTileMapNodes using BSP trees. Tutorials on SKTileMapNodes can be found elsewhere.