Zee's Natural Disasters

natural-disasters

Server-authoritative natural disasters for Godot 4: thunderstorm, tornado, blizzard, wind and earthquake, plus a director that schedules them. Part of the TMC Dot family; dot-core is the only hard dependency, and dot-server's console is used when present (duck-typed, never imported).

A disaster is a small record (DotDisasterEvent) that the authority sends once. Paths, gusts and shaking are deterministic functions of the record's seed and elapsed time, so clients draw the same funnel without a position ever being sent. The only per-event traffic afterwards is lightning strikes. Clients draw and never simulate.

Using it

var disasters := DotDisasterManager.new()
disasters.authority = multiplayer.is_server()
disasters.send_fn = func(msg: Dictionary) -> void: my_broadcast(msg)   # authority only
disasters.damage_fn = func(target, amount, at, ev) -> void: target.hurt(amount)
add_child(disasters)

disasters.start(&"tornado", {"origin": Vector3(0, 0, 0), "duration": 60.0})   # returns a DotResult

On a client, feed every message the authority sent to disasters.receive(msg) (a DotResult; forged or malformed records are refused) and, when a player joins mid-disaster, call disasters.send_snapshot(func(msg): send_to_that_peer(msg)) on the authority: it hands the callable one start per running disaster (snapshot() returns the same list). A host can set every hook in one line, disasters.wire({"damage": ..., "push": ..., "send": ..., "bodies": ..., "players": ..., "origin": ...}) (a typo is CODE_INVALID), and DotDisasterManager.damage_via(&"hurt") / push_via(&"add_push") build the two hooks that just call a method on the target. start on a client and receive on the authority are both CODE_FORBIDDEN. dot-net is not imported: carry the dictionaries over whatever channel the game already has.

Nodes (all Dot-prefixed, no autoloads, hosts found through DotNodeRef):

• DotDisasterManager: owns the disasters, the registry of kinds and the views. Hooks: send_fn, damage_fn, player_push_fn, bodies_fn, players_fn, origin_fn. Targets are found by group (disaster_bodies, disaster_players) or by the hooks; set meta disaster_immune to exempt a body. Duck methods on a target: apply_disaster_push(dv), apply_disaster_damage(amount, at), take_damage(amount).
• DotDisasterDirector: schedules disasters on a seeded random interval, weighted by kind, honouring max_active and kinds.
• DotDisasterShake: camera shake through h_offset/v_offset only, never the transform.

Queries for a game's own physics: wind_at(point) (a vehicle can be pushed by it), shake_at(point), is_active(kind), active(). Lightning on cue: get_kind(&"thunderstorm").strike(event, manager, at_point).

Registering your own disaster

Subclass DotDisasterKind (id, defaults(), server_start/tick/end, make_view, shake_at, wind_at) and call manager.register_kind(kind); it returns CODE_CONFLICT for a taken id unless replace is true. A kind registered after a console is bound gets its cvars too. stock_kinds = false leaves the five stock kinds out. A game with its own weather (rain on a delivery route, say) registers a kind rather than forking.

Settings and cvars

Layered like the rest of the family: exported defaults, JSON file, environment (DISASTERS_), command line (--disasters-), then cvars on a bound console (manager.bind_console(console)), each named disaster_<key>: director_enabled, interval_min, interval_max, max_active, kinds, seed, affect_all_bodies, lightning_damage, tornado_damage, and per kind <kind>_intensity, _duration, _radius, _weight. Commands: disaster <kind> [intensity] [duration] [radius], disaster_stop [kind], disaster_list.

Examples and tests

godot --headless --path . --import
timeout 300 godot --headless --path . res://examples/disasters_selftest.tscn   # 116 checks
xvfb-run -a godot --path . res://examples/disasters_demo.tscn -- --kind tornado --shot out.png

The demo is interactive without --shot (keys 1 to 5 start a disaster, 0 stops).

Credits

• Models in assets/kenney/nature/: Kenney Nature Kit, CC0, https://kenney.nl (licence kept in the folder). Used by the example scene only.
• Sounds in addons/natural_disasters/audio/: synthesised by tools/make_sounds.py (numpy and ffmpeg, fixed seeds), CC0 by the authors of this repository. Kenney has no thunder, so they are generated.
• Textures are generated in code.

Code is MIT (see LICENSE). The design was informed only by a public description of what such disasters do; no third-party code or assets were used.