Project settings and config

The goal: values designers tune in Project Settings, saved in the project’s ini files, and read by the game.

#![allow(unused)]
fn main() {
use bindings::developer_settings::DeveloperSettings;

#[uclass(parent = DeveloperSettings, config = "Game")]
pub struct CombatSettings {
    #[uproperty(Config, EditAnywhere, category = "Combat", default = 3)]
    max_combo: i32,

    #[uproperty(Config, EditAnywhere, category = "Combat", default = 0.4)]
    combo_window: f32,
}

#[uclass_impl]
impl CombatSettings {}
}

• A class whose parent is DeveloperSettings and that names a config category shows in Project Settings.
• config = "Game" saves its Config properties in the Game category’s files: Config/DefaultGame.ini for the project’s defaults.
• The values live on the class default object, which get_default() returns:

#![allow(unused)]
fn main() {
let settings = CombatSettings::get_default()?;
let window = settings.combo_window();
}

Binding the module

DeveloperSettings is its own engine module. A game binds it by adding it to [codegen.modules] in rusteal.toml, then running rusteal build --all:

DeveloperSettings = { module = "developer_settings", feature = "engine" }

Plugin templates already bind it.

In the editor

Open Edit > Project Settings. The class has a page of its own, named after the class, listed under Game by default. Changing a value there writes it to Config/DefaultGame.ini:

[/Script/Rusteal.CombatSettings]
MaxCombo=4
ComboWindow=0.35

The section is the class’s path, and the keys the properties’ Unreal names. A plugin’s settings use the plugin’s package ([/Script/Inventory.InventorySettings]).

Screenshot: the Project Settings page of a Rust DeveloperSettings class. (images/systems/project_settings_page.png)

Config on other classes

Any class can read properties from ini files: name a category in #[uclass(config = "...")] and mark the properties Config. The values are read into the class default object when the class is created, as in C++. Game, Engine, Input and GameUserSettings are the engine’s categories; any other name makes a category of its own (config = "Combat" reads Config/DefaultCombat.ini).