Aava: an open world that comes alive as you build in it

Aava /ˈɑːʋɑ/ — Finnish for vast, open expanse, said most often of the open sea (aava meri) or a wide, unobstructed landscape. Where the word itself comes from is not settled: it may be a variant of aapa, the term for the open, treeless mires of Finland's north, shifted by association with avata, "to open"; or a separate borrowing from Sámi. Either root points the same way — a country you can see all the way across, and build anything in, which is the freedom the game is actually built around. Finland is also, out of all proportion to its size, a games country — Supercell, Rovio, Remedy — and a small project made by one person on evenings and weekends is not a strange place to borrow a word from it.

Aava is a 3D exploration-and-building game for children, written in GDScript on Godot 4. The valley is a pure function of one integer seed: the ground, the river, the forest and the mountains are computed rather than stored, so nothing about the world has to be saved, sent between two machines playing together, or loaded from a file. What is saved is only what a child has changed — see Every world is one integer, below.

The loop is creation rather than collection. Everything built makes the valley more alive, and the more alive it is the more it gives back: plant a grove and birds arrive, feed an animal and it becomes a friend, raise a house with a bed and a fire and it becomes somewhere to actually spend the night rather than a shape standing in a field. Coins come from looking after things, and are spent on tools that widen what a child can reach — an axe, shears, a lantern, a bicycle, a motorcycle, a quad, a horse to ford the river a wheeled machine cannot — rather than on numbers going up.

Since the first line of this file was written, the valley has grown mountains with snow on their shoulders and ice in their hollows, a river long enough to be worth following, two lakes — one of them up a hillside, holding its own water at its own height — a day/night cycle with a lantern for the dark, a bow range, a herd of twenty horses and a shop to buy a mount from, a flock of sheep to shear and cows to milk, an economy where felling a tree costs what growing one paid, campfires that need feeding and beds worth sleeping in, animals that speak on their own terms, and a whole ambient soundscape synthesised from nothing but code.

There is a fairground across the river with a carousel, two moving walkways, a trampoline, a fifty-metre wheel and a wooden coaster with two vertical loops, whose speed is integrated from the slope of its own track — the loops are sized by what the drop actually pays out, v² ≥ 5gR, rather than by eye. A bridge crosses to it, because a machine on wheels cannot ford the river and a horse can; street signs stand where the four roads meet, each turned by asking where its own road actually goes. And a way to invite another player into your own copy of the valley over the local network, and talk to them while you play.

The code is AGPL-3.0-or-later. The name Aava, the application id and the icon are reserved and are not covered by that licence; see NOTICE.md.