Worldmeteorshower

Based on game build 714014 | Last updated: 2026-03-03

Overview

Worldmeteorshower is a world-level component that manages the probability and logic for replacing standard moon rocks (rock_moon) with moon rock shells (rock_moon_shell) during meteor showers. It tracks a cumulative chance (moonrockshell_chance) that increases when a moon rock is dropped, and uses this to determine whether a shell should be generated instead. It also supports additive modifiers to the base chance via SourceModifierList.

This component is intended to be attached only to the master simulation world entity (TheWorld), as enforced by an assertion in the constructor.

Usage example

if TheWorld.ismastersim then
    TheWorld:AddComponent("worldmeteorshower")
    local prefab = TheWorld.components.worldmeteorshower:GetMeteorLootPrefab("rock_moon")
    local instance = SpawnPrefab(prefab)
end

Dependencies & tags

Components used: SourceModifierList (from util/sourcemodifierlist.lua)
Tags: None identified

Properties

Property	Type	Default Value	Description
moonrockshell_chance	number	0	Accumulated probability (0–1) that the next moon rock drop will be replaced with a moon rock shell.
moonrockshell_chance_additionalodds	SourceModifierList	SourceModifierList(self.inst, 0, SourceModifierList.additive)	Additive modifier list for adjusting the base moonrock shell chance (e.g., via game mode tuning or events).

Main functions

GetRockMoonWaveOdds()

• Description: Returns the current additional odds (from modifiers) for a moonrock shell to appear if the base moonrockshell_chance is less than 1. Used to expose modifier-driven adjustments for UI or logic.
• Parameters: None.
• Returns: number — the current total additive odds value, or 0 if moonrockshell_chance >= 1.

GetMeteorLootPrefab(prefab)

• Description: Determines the actual loot prefab to spawn based on meteor loot rules. For "rock_moon", it may replace it with "rock_moon_shell" depending on accumulated chance and random check. For "rock_moon_shell", ensures no duplicates and updates state. Returns the final prefab name and optionally a flag indicating special handling.
• Parameters:
  prefab (string) — The requested loot prefab ("rock_moon" or "rock_moon_shell").
• Returns:
  prefab (string) — The actual prefab to spawn.
  (optional) is_shell_duplicate (boolean) — true only when the input was "rock_moon_shell" but it was downgraded to "rock_moon" to avoid duplicates.
• Error states:

• If moonrockshell_chance >= 1 and input is "rock_moon_shell", it returns "rock_moon" and a true flag to indicate it was downgraded.
• Otherwise, if the chance conditions are met, it sets moonrockshell_chance = 1 and returns "rock_moon_shell".

SpawnMeteorLoot(prefab) (Deprecated)

• Description: Legacy wrapper to spawn meteor loot. Internally calls GetMeteorLootPrefab() and then SpawnPrefab(). Kept for mod compatibility.
• Parameters:
  prefab (string) — The requested loot prefab.
• Returns: entity — The spawned instance from SpawnPrefab().
• Error states: None beyond what SpawnPrefab() may throw.

Events & listeners

• Listens to: None
• Pushes: None