Opinions sought about door differentiation

Hey All–
In your parser games, how do you like your doors differentiated from each other?

If you’re in a room with 4 locked doors, one in each cardinal direction, do you like them to be the north door, the south door, etc? Or the red door, the blue door, etc?

What are preferences here? Any ideas are welcome.


In your example, I for one would actually definitely call them by their cardinal directions. In other cases where I have to differentiate a door, I make liberal use of “printed names” so that behind the scenes, I can call duplicate doors whatever the hell I want.


In general programming there’s an idea called Postel’s Principle or Postel’s Law. It’s originally from networking programming, but I think it applies to game design as well. It’s the idea that you ought to be broad in what you accept, but narrow in what you produce.

In this particular case, if the description is something like, “There’s a blue door on the north wall…” and so on, then you should obviously accept >UNLOCK BLUE DOOR and >UNLOCK NORTH DOOR as synonyms. The additional caveat I’d add is that you should probably pick one designation to prefer and use it consistently…so generally avoid referring to the “north door” in one place and the “blue door” in others, unless it’s somehow or other dictated by circumstances.

That doesn’t answer your question.

As a general matter, I think the rule of thumb is to pick the most unique thing about the door(s) and use them as your “preferred” disambiguator. If you’ve got blue doors elsewhere, then that would mean preferring direction in this case, but absent that I’d assume that you’re more likely have more directional doors elsewhere, so color (or some other thing) is a better “primary” attribute to identify the doors with.

If none of that applies, I’d fall back on the design of the puzzle: what are those doors doing there in the first place? If the blue door is on the north wall because that’s the direction the reactor core is in, then maybe it makes more sense to identify it as the reactor core door. Or whatever.

And if none of that sorts it out, as a final desiderata I’d prefer a more typable adjective over a less typable one. If it’s a high traffic area (or a puzzle where the player is going to spend a lot of time jigging the knobs working on it) this could rank higher.


I like to not use doors as much as possible, just pretending they don’t exist. If I have to use them, I try to limit them and make them different materials (like wood or stone), conditions (like battered or cold), or colors.

In places where doors have to be pretty uniform (like if I had to recreate the military base in Spider and Web) I’d prefer to refer to them by their function (lab door), and if that fails, then I would do cardinal directions.

Usually when I end up with rooms that have four otherwise-indistinguishable doors, i feel like something’s gone wrong with map design. Games with lots of connecting rooms tend to be more boring than ones with interesting rooms side by side. I know you personally don’t have this problem, but if anyone out there has a room called “corridor7” or something in your code, you may have a problem.

Edit: just looked at my current WIP and I have a landing room with nothing in it but four exits, one of which is solely referred to as the ‘western door’. So maybe ignore everything I said because I clearly don’t practice what I preach lol

Edit edit: I just checked and the door itself isn’t even implemented, just mentioned in the text haha


Yeah. To a first order approximation a room is a space in which at least one important thing happens. That generally shouldn’t be literally true, quite, unless you’re going for an extremely tight/claustrophobic effect. Because in IF, like in painting or in music or anything else, the use of space (that is, stretches of “nothing”) is as important as the use of the “real stuff”. But as a general rule if you’re designing a game, your first pass is going to be too big. Like, waaaay too big. So then you should ruthelessly prune things back. Keep going until something breaks. Then revert back to the last change where nothing broke. That, more or less, is about how big your game should be.

Of course that’s just a rule of thumb, and it assumes a sort of narrative (or other) focus that you can design around. There are plenty of games, very compelling games, that are designed in radically different ways—I love Cosmology of Kyoto, for example, and it’s more or less all random side stuff and that’s kinda the whole vibe.


You know this already, Amanda, so this isn’t really directed at you, but I should start by saying that doors are generally uninteresting for reasons Brian has already mentioned. They are realistic in the sense that buildings and houses have lots and lots of them, but reality, unfortunately, is no game.

I’m pretty sure that you are of the same mind, because I recall that the doors were quite trouble free in, say, Fairest.

E: though I really should disclose that I have two problem doors in my own WIP. :disappointed:

Without knowing more about your intent, it’s hard to say. Are the doors mysterious? In the old Resident Evil games, keys and doors were matched by a visual indicator. A door with a shield emblem and a key to match. Resident Evil 2 used playing card suits, instead. An image or motif (even if not very relevant) is likely more interesting than a color or direction.

However: perhaps indeterminacy is part of the design, in which case they should all look the same. Perhaps compass directions don’t even work there, and the player must write on the doors like the cubes in Spellbreaker. Much depends on what you are trying to do!

If the place is just a constructed hub in a constructed structure that is not meant to be confusing AND it would be beneficial to have doors, I would go the Resident Evil route and use symbols or figures to represent each direction. Just because it’s more interesting than compass directions, and because they can participate in your fictional world if desired.

If the doors have purpose or very different destinations, the doors could match the destination: airlock door, reinforced metal door (understood as metal door of course), cell door, and whatnot.

I think I’d only use cardinal directions and matching doors if I was building a maze.


In my case, the doors are doors and I have a reason for them to be doors. They will not be difficult to operate, but choosing a door will be important. At first, they will all be unremarkable. They could all be plain doors (just NESW) or differently colored doors, or doors made of different materials, etc. But there will not be an overt reason to pick one over another. I just need them differentiated in the least annoying way possible.

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OK. To me personally, I’d prefer different symbols or materials because I’d remember them more easily than directions

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I would go with direction. The player already needs to be thinking about which direction the exit is in, so that’s not any additional information to remember; color or material is.

Here’s the code from Enigma for directional doors:

Door-directionality relates a door (called the door-in-question) to a direction (called the direction-in-question) when the room-or-door direction-in-question from the location is the door-in-question.
The verb to lead toward means the door-directionality relation.
The verb to lead through means the reversed door-directionality relation.

Understand "[something related by door-directionality]" as a door.
Understand "door" or "door to" or "door to the" as a door.

After printing the name of a door:
    let the way be a random direction that leads through the item described;
    say " to [the way]".

With this, doors will automatically be described as “door to the east” and so on, and the player can “EXAMINE EAST” etc. (And when they go through, it’ll become the “door to the west”.) In Enigma I actually applied these rules only to a sub-kind called “internal-door”, but you can just as well apply it to all doors.


With your additional information, I’d recommend looking at Delightful Wallpaper by Zarf, which has a lot of very similar doors but is simple and easy to navigate and has source code.


I’d just like to point out the obvious thing you probably don’t need pointed out, but once you pass through a North Door, it’s now south of you. So directional naming could be confusing. I usually do blue door, wooden door, steel door, weathered door, etc.


I always abstract doors in the sense that opening door is implied in travelling between places where a door is to be expected, if said door isn’t locked or its nature has implications (e.g. a sturdy steel door imply that there’s something interesting beyond it, more so if is locked…)

Best regards from Italy,
dott. Piergiorgio.


I like colors or something unique so I can type “unlock green”, whereas (I think?) with directions you have to say “unlock north door” because “unlock north” will require disambiguation? So it’s less typing.

Unless I’m wrong about the disambiguation thing, in which case I don’t have any real preference…


Coloured doors are like… sóó nineteeneighties.

In fact, I don’t like any of the suggestions for making the doors different materials or appearances. (wood, iron, weathered, shiny,…)
These all raise different expectations about what’s behind them. And that’s not what you want, right?

So I gather the appearance of the doors themselves should not be a reason to pick one over the other.

I like identical plain NSEW-doors, but I also want to suggest just numbering the doors. (doors 1234, doors ABCD). It puts the smallest of detail on the door to identify it without resorting to the compass, while remaining as neutral as possible.


This is a trope established by Infocom to avoid disambiguation problems - often for Enchanter scrolls: “crinkly scroll/weathered scroll/tattered scroll/yellowed scroll/charred scroll…” - and it kind of becomes the go-to solution to differentiate similar objects.


Yes. Should I have put a smiley after that sentence?

About numbered doors, they do trigger the player to just open them in numerical order, instead of random. Colour would be better for that, with players having different favourite colours. (But colours carry associations too. A red door is more dangerous than a blue one.)

Edit: maybe a cross, a circle, a square and a triangle?


The “unassuming” door, the “nondescript” door, the “ordinary” door, and the “plain” door.


Corridor of Doors
You can see a poppy-red door, a dusty-rose door, a cardinal door, a brick-red door, a ruby door, and a blue door (with jagged teeth) here.


Yes. This.


What game is this Corridor of Doors from? Or did you just make it up on the fly?

It strongly reminds me of a game I played many years ago, during my first foray into IF. It had the PC exploring a house/mansion, and in the cellar there was a maze-like area not unlike what you describe. Lots of doors in different colours, but also different shades of the same colour.

I can’t remember the name of the game now. Heck, it must be at least fifteen years ago. I don’t even remember if I finished it.