I developed/run a private server for the game that many members of the Diablo team made after Diablo II (Hellgate: London) and the same technique is used for random dungeon generation, but using 3D assets and 2d flat floormap shapes to make the combinations. In fact, it's even called the same thing, DRLG!

Sometimes the game tries a few thousand combinations when a player enters a dungeon before being satisfied by the results (there are configurable constraint sets).