It’s more than easy to see how doors can exponentially complicate the logistics of a game. Let’s say that an NPC in The Witcher 3 wants to turn in for the night. Without any doors to consider, all that the NPC has to do is to map a route from the current position of the character to their bed. Throw a door in the way, and the same NPC will need to recognize that there is a door blocking the way. It has to have logic to control the way it interacts with the doors.
Doors Can Be Difficult to Code
What would happen if two NPCs used the same door at the same time? How does one know whether a door opens toward or away from them? This and many others are found to be problems troubling game designer Liz England, who worked on games like Sunset Overdrive and Watch Dogs: Legion. He calls this “The Door Problem.”
In a tweet, Stephan Hövelbrinks, who is a developer of Death Trash claims that developers of AAA games hate doors. He even points out that the Assassin’s Creed games solved this by pretending they were never invented in the first place. In their recent game, Assassin’s Creed: Valhalla, some doors were placed in certain puzzles, though. This tweet quickly went viral as game developers chimed in to talk about all the headaches that a door could cause.
In response to Hövelbrinks’ tweet, former BioWare Austin developer and current creative director at Boss Fight, Damion Schubert, posted an entire thread that’s dedicated to explaining all the challenges that videogame doors bring.
Even the co-director of The Last of Us 2 said that they were a “waking nightmare”. Kurt Margenau wrote that it was the thing that took the longest to get right. In follow-up tweets, Margenau details that Naughty Dog went through some exhaustive processes to get doors working properly and the clever behind-the-scenes hacks required. For example, when players are in combat situations, they will slam the door closed behind them automatically to impede enemies that might be chasing them, while in regular exploration, the doors stay open. This way, players remember where they have been in the game.