Weather

The sky every client shows is one of the level’s time-of-day profiles - the same ones on all three levels - and the server names it for everyone: SetWeather in a mode, /weather in the chat, [world] weather in server.toml for the start. A preset is a friendly name for a profile, one per kind of weather; a profile name passes through as it is, which also admits the profiles the game’s own quests use (q_* names in the level’s mission file). Each client blends a change in over [world] weather_blend seconds (10 by default) unless the call names its own blend.

Preset	Profile	What it looks like	Rain	Chance by default
clear, sunny	cloudless_sunny	a clear sky	-	20
fair	semicloudy_clear	a few clouds, clear light	-	25
cloudy	cloudy_no_rain	overcast without rain	-	20
overcast	summer_overcast	a heavy summer sky	-	12
showers, rain	cloudy_frequent_showers	clouds and passing rain	0.5	10
drizzle, fog	foggy_drizzly	fog and a fine rain	0.25	6
storm	foggy_storm	a storm with rain	1	4
dry_storm	foggy_storm_no_rain	the storm’s sky without the rain	-	3

The server’s rotation

"" (an empty name, and the shipped [world] weather) hands the sky to the server’s rotation: every 3 to 5 game hours it rolls the next sky from the chances - the column above unless the mode set its own with SetWeatherChances - and every client follows it, so all players stand under the same sky (each game’s own rotation is switched off), and a player who joins gets the sky up now. The chances are relative weights: with the column above a storm comes up about one sky in 25. The same sky may come up again and simply stays, so over a long run each kind is up about its share of the time. /weather auto goes back to the rotation and /weather chances shows the chances in force.

-- a wet autumn: rain most of the time, a storm now and then, each sky for 2 to 4 game hours
SetWeatherChances({cloudy = 20, overcast = 15, showers = 35, drizzle = 20, storm = 10}, 2, 4)

The same from a C# game mode, in its OnInit (the C# API: -1 for the hours keeps the server’s own hold, null chances its own mix):

var chances = new Dictionary<string, double>
{
    ["cloudy"] = 20, ["overcast"] = 15, ["showers"] = 35, ["drizzle"] = 20, ["storm"] = 10,
};
if (!api.SetWeatherChances(chances, 2, 4, out var reason))
    api.Log($"weather: {reason}");

A mode sets its chances at its start or at any time later (a season, an event); until it does, the server rolls the column above. The game modes that come with the server keep theirs in a WEATHER table at the top of the script, with the default mix in it.

The rain

The rain comes with the profile - the Rain column, the rest stay dry - the same amount on every client. SetRain (/rain, [world] rain) forces another amount from 0 to 1; -1 hands the rain back to the weather. GetWeatherPresets returns the presets and their profiles to a mode.

The variants and the game’s own chances

In single player the game rolls its own sky from more profiles: most kinds have a _B (and some a _C) variant - another look of the same weather, some with rain of their own. A mode may name any of them in SetWeather or as a key of the chances. The game’s own chance of each, for a mode that wants the single-player mix:

Profile	Kind	The game’s chance	Rain
cloudless_sunny	clear	0.2	-
cloudless_sunny_B	clear	0.4	-
semicloudy_clear	fair	0.5	-
semicloudy_clear_B	fair	0.6	-
cloudy_no_rain	cloudy	0.5	-
cloudy_no_rain_B	cloudy	0.6	-
cloudy_no_rain_C	cloudy	0.2	-
summer_overcast	overcast	0.2	-
summer_overcast_B	overcast	0.2	0.4
summer_overcast_C	overcast	0.1	0.3
summer_overcast_B_no_rain	overcast	0	-
cloudy_frequent_showers	showers	0.5	0.5
cloudy_frequent_showers_B	showers	0.5	0.8
foggy_drizzly	drizzle	0.1	0.25
foggy_drizzly_B	drizzle	0	0.25
foggy_storm	storm	0.3	1
foggy_storm_B	storm	0.2	1
foggy_storm_no_rain	dry storm	0	-

-- the single player's own mix (the weights only need to be in proportion)
SetWeatherChances({
  cloudless_sunny = 2, cloudless_sunny_B = 4, semicloudy_clear = 5, semicloudy_clear_B = 6,
  cloudy_no_rain = 5, cloudy_no_rain_B = 6, cloudy_no_rain_C = 2,
  summer_overcast = 2, summer_overcast_B = 2, summer_overcast_C = 1,
  cloudy_frequent_showers = 5, cloudy_frequent_showers_B = 5, foggy_drizzly = 1, foggy_storm = 3, foggy_storm_B = 2,
})