Renga in blue

Friday, February 04, 2005

Structural elements vs. puzzles

In James Bond: Everything or Nothing there's a 2-player cooperative mission mode. Throughout the mission there are doors with two buttons; both buttons must be pressed at the same time for the corresponding door to open.

In some contexts this might be called a "puzzle". However, because the layout is consistent -- the buttons are always to the left and right of the door -- it's not a puzzle at all, but a structural element of the level. The doors force both players to be in the same location at once.

In interactive fiction, the equivalent sort of thing can be found with locks and keys. There may be a door with a corresponding key, and some difficulty involved in finding that key, but once the key is located unlocking the door represents a trivial puzzle. The actual matching of key to door is acts as a structural element (forcing the key to be found first) rather than a puzzle.

In Photopia, an early scene involves resuscitating a person. The player is given directions on what to do and a NPC intercedes if the player is simply passive. The events represent player action but do not represent a puzzle. The commands the player enters are part of the structural elements, but not a puzzle.

Later on (with the storytelling scenes), there are some "easy" puzzles. These are not merely structural -- the player is not told what to do, and some people have gotten stuck. The actions are strongly implied, but the leap to blatant obviousness isn't there.

The question I have is, at what point does something turn from structural element into puzzle? Clearly in Photopia's case the direct commands from an NPC managed it, but what about the more subtle ways? The structural aspect of the lock and key seems to derive from convention -- if there was only one IF game that used keys and locks, would that constitute a puzzle because of the lack of repetition? Intuitively, I'd say no -- I can't imagine a player of Dreamhold being stuck on the first locked door once they have a key -- but I have difficulty pinning down the exact reason why.

The interest to an experimental IF writer here would be to explore what limits there are in "puzzle-less" IF. Which sort of actions are allowed when avoiding puzzles, and which represent some sort of difficulty and are therefore off-limits?