When you think about the most difficult parts of making a game, it’s unlikely that the humble door would be front of mind–unless you’re a game dev who’s attempted doors before. A Twitter thread by indie dev Stephan Hövelbrinks, who is working on Death Trash, revealed that doors are notoriously within game development, with developers on titles like The Last Of Us Part 2 and The Witcher 3 chiming in to agree.
Hövelbrinks explains that the biggest issues arise from doors being “a dynamic funnel and block in the pathfinding, potentially locked, potentially destructible, but in general because they sit potentially between any game interaction or character to character situation from here to there.”
Proving his point, locked doors have been the cause of a number of game-breaking bugs, even in high-profile AAA games. Hövelbrinks points out that some AAA devs avoid using doors at all, such as the entire Assassin’s Creed series until Valhalla–though even Valhalla’s implementation of doors was often glitchy and not too popular with fans.
The Last of Us Part II co-game director Kurt Margenau wrote a Twitter thread on the subject, talking about how difficult it was to design doors that worked with combat, stealth, and still fitted in with the game’s realistic animations.
Margenau credits the tricky game physics the doors required to developer Jaros Sinecky, who has already seen acclaim for his work on TLOU2’s impressive rope physics. Sinecky also contributed to the incredibly detailed glass-breaking mechanic we investigated last year.
Other developers have chimed in on the subject of doors, with some simply commiserating on how difficult they are, and others explaining how they fixed door-related bugs, or simply got around having to use doors at all.
Y’all when we made TWD:S&S we literally had a designer whose entire job was doors and we were still panicking about them pretty much all the way until ship 💀 https://t.co/cckgbZrsPE
— 罗薇 Ameorry Luo 🔪 (@dustandhalos) March 9, 2021
In Witcher 3 we had a door in prologue that would lock during boss fight and unlock after fight is done. We found 12 scenarios in which it would not unlock i.e. player saved after the fight and loaded the save trapping the player. The 13 fix was not to have the door ever lock xD https://t.co/bNkpIPaMdO
— Marcin Pieprzowski 🏳️🌈 (@GingerNaTT) March 9, 2021
My solution was to make doors only visual: These fake doors open/close based on the distance to the nearest character.
For the times when I need an unlockable door, they can only be unlocked, they never revert to their locked state.
— Aivaras Klimas (@DeveloperZuurix) March 9, 2021
I don’t exactly know how many man-months went into the door system in Control, but more than most abilities and weapons, for sure.
— Sergey Mohov (@krides) March 9, 2021
So next time you’re playing a game with doors, take a moment to stop and appreciate how difficult they must have been to implement–especially if they lock and unlock.
