Bevy Romance

Genre router. Domain work lives in the Bevy skills below.

When to use

Load this for relationship values and scene routes on top of dialogue.

ECS shape

• Components hold the genre's per-entity flags as plain data. This file does not name new engine types.
• Resources hold run-wide counters (score, wave index, seed) via bevy-data-resources.
• Systems read those components on Update or the fixed timestep from bevy-master. Order them with .chain() when a later system must see the result.
• Schedule: gameplay mode changes go through bevy-state-machines. Affection and route flags below are a component plus one resource.

Examples

[dependencies]
bevy = "0.20"

Each character stores affection and the last choice. Route flags are a resource. Apply the choice, then pick the next scene id. Those systems share Bond, so they chain.

#[derive(Clone, Copy, PartialEq, Eq)]
enum Choice {
    Warm,
    Cool,
}

#[derive(Component)]
struct Bond {
    affection: i32,
    last: Choice,
}

#[derive(Resource)]
struct RouteFlags {
    confession_open: bool,
    scene: u32,
}

fn boot(mut commands: Commands) {
    commands.insert_resource(RouteFlags {
        confession_open: false,
        scene: 0,
    });
    commands.spawn(Bond {
        affection: 0,
        last: Choice::Cool,
    });
}

fn apply_choice(keys: Res<ButtonInput<KeyCode>>, mut bonds: Query<&mut Bond>) {
    let choice = if keys.just_pressed(KeyCode::Digit1) {
        Some(Choice::Warm)
    } else if keys.just_pressed(KeyCode::Digit2) {
        Some(Choice::Cool)
    } else {
        None
    };
    let Some(choice) = choice else {
        return;
    };
    for mut bond in &mut bonds {
        bond.last = choice;
        bond.affection += if choice == Choice::Warm { 10 } else { -5 };
    }
}

fn advance_route(bonds: Query<&Bond>, mut route: ResMut<RouteFlags>) {
    let Some(bond) = bonds.iter().next() else {
        return;
    };
    route.confession_open = bond.affection >= 30;
    if route.confession_open {
        route.scene = 4;
    } else if bond.last == Choice::Warm {
        route.scene = 2;
    } else {
        route.scene = 1;
    }
}

fn install(app: &mut App) {
    app.add_systems(Startup, boot)
        .add_systems(Update, (apply_choice, advance_route).chain());
}

A scene is available when affection is at least the threshold stored on that scene.

#[derive(Component)]
struct SceneGate {
    id: u32,
    min_affection: i32,
}

#[derive(Component)]
struct Bond {
    affection: i32,
}

fn gate_open(bonds: Query<&Bond>, gates: Query<&SceneGate>, scene_id: u32) -> bool {
    let Some(bond) = bonds.iter().next() else {
        return false;
    };
    gates
        .iter()
        .any(|gate| gate.id == scene_id && bond.affection >= gate.min_affection)
}

Scene shape

Routing

• bevy-dialogue-system - Scenes.
• bevy-rpg-stats - Affection as a stat you name.
• bevy-save-load - Route flags.

Scope

• Affection lives on Bond. RouteFlags stores the open scene. Bevy has no relationship type; the example above is the data.

Expert Knowledge Delta

Target: Bevy 0.20+.

Core ECS types: Component, Resource, Query, Commands, Startup, Update, Fixed / FixedMain (bevy::time), .chain(), Plugin, DefaultPlugins, MinimalPlugins. Messages and observers are an ownership slot. See bevy-events-messaging for their APIs. Systems run in parallel unless .chain() orders the ones that conflict.

Who owns state

Borrow rule: two systems that both mutably query the same component must be ordered (.chain()) or split so only one writes. Unrelated systems stay parallel. That is the ECS page rule, not a guess at a system-set API.

Decision

Load references/ecs-ownership.md for the ownership table.

NEVER

• Do not pin /0.20.0/ in docs URLs. WHY: links stay on latest; the 0.20 target is stated once in prose.

• Do not mutably query the same component from two unordered systems. WHY: the schedule runs systems in parallel unless .chain() orders them.

• Do not invent a physics, navigation, networking, or XR crate here. WHY: this skill only names documented Bevy crates and modules.

• No foreign-engine types in Bevy code. WHY: Bevy code stays idiomatic ECS and uses only documented Bevy APIs.

• No invented genre APIs. WHY: Bevy code stays idiomatic ECS and uses only documented Bevy APIs.

• Do not pick a physics or net crate here. WHY: Bevy code stays idiomatic ECS and uses only documented Bevy APIs.

Reference

Official pages stay on unversioned permalinks. The library pin on bevy-master stays 0.20.

Official Documentation

• Assets - Official asset catalog. No third-party crate was selected.
• Examples - Example tree on the latest branch.
• ECS - Component, systems, Query, Startup, Update, and .chain().
• Plugins - Plugin, DefaultPlugins, MinimalPlugins, and add_plugins.

Related Skills

Prerequisites

• bevy-master - ECS ownership and schedules.
• bevy-ecs-composition - Spawn and query shape.

Complements

• godot-genre-romance - Peer skill for the same genre.
• bevy-dialogue-system - Scenes.
• bevy-rpg-stats - Affection as a stat you name.
• bevy-save-load - Route flags.

Downstream / consumers

• None. This router does not own a second implementation.

Master

• bevy-master - Bevy router.