Bunnyland Aquasim

Out-of-tree Bunnyland plugin that adds swimming, diving, and the underwater — an expansion-pack-sized themed bundle of aquatic mechanics. Water rooms are their own little survival puzzle: dive deep, hold your breath, and surface with treasure. It is a natural companion to river-fording and fishing worlds.

The pack bundles five mechanics, each in its own module with its own tests:

• Water rooms / submersion — a SubmergedComponent tags a room as deep water; any room with an aquatic RoomComponent.biome also counts. Being submerged gates movement and drives the breath timer.
• Breath + drowning — a BreathComponent meter (built on the shared needs Meter) drains while submerged and refills at the surface; running out damages HealthComponent. A held RebreatherComponent stretches every breath.
• Diving for treasure — a dive verb recovers loot from sunk caches with deterministic loot tables (a hash of the cache id and world epoch — no randomness); surface swims up an exit to dry land and catches your breath. Diving rejects if you cannot swim or have no air.
• Currents & hazards — a CurrentComponent drifts swimmers toward an exit each tick; a HazardComponent bites the ungeared. Strong swimmers resist both.
• Swim skill — a SwimSkillComponent that improves with use, reducing breath drain and hazard damage and letting a master hold their ground against currents.

This repo intentionally keeps all aquatic work outside the main bunnyland-server repo.

Layout

• server/ — Python Bunnyland plugin package with the components, the breath / current / hazard consequences, prompt fragments, a worldgen enrichment hook, the dive/surface verbs, spawn factories, and tests.

Server Plugin

The plugin exposes bunnyland_aquasim.bunnyland_plugins() and contributes:

• SubmergedComponent, RebreatherComponent, TreasureCacheComponent, BreathComponent, SwimSkillComponent, CurrentComponent, HazardComponent.
• BreathConsequence — drains/refills breath and drowns the airless each tick.
• CurrentConsequence and HazardConsequence — drift swimmers and damage the ungeared.
• submersion_fragments, breath_fragments, swim_fragments — prompt fragments.
• AquaWorldgenHook — floods aquatic generated rooms and sinks treasure caches.
• dive and surface — verbs for the diver (human or AI).
• spawn_rebreather, spawn_treasure_cache — spawn factories.
• Optional Bunnyland 3D integration adds aquatic plants and coral plus an underwater enclosure skybox and a slow suspended-silt particle field in water rooms.

Running

This package builds no containers. It is loaded into the stock server via --module:

bunnyland serve --module bunnyland_aquasim

default_enabled=True, so no --plugin flag is required once the module is imported. The bunnyland_aquasim package must be importable by the server (installed into the server's environment, or on PYTHONPATH).

Development

Run server tests against a sibling bunnyland-server checkout (no install required — server/tests/conftest.py puts both packages on sys.path). From server/:

uv run --project ../../bunnyland-server -m pytest
uv run --project ../../bunnyland-server ruff check src tests

See server/README.md for more detail.

Contributing & Conduct

This plugin follows the Bunnyland project's contribution guidelines and code of conduct, which point back to the bunnyland-server repository.

License

Licensed under the GNU Affero General Public License v3.0. See LICENSE.