Bevy ECS Markers

Adds the support for marking entites and fetching them in queries

Example

View more examples here

#[derive(EntityMarker)]
enum Players {
    Red,
    Blue,
}

#[derive(EntityMarker)]
#[marker(data_name = "CurrentPlayerMarker")] // specify how the generated MarkerData struct should be called
struct CurrentPlayer;

#[derive(Component)]
struct Player(u32);

fn setup(
    mut commands: Commands,
    mut markers: MarkerMut<Players>,
    mut current: MarkerMut<CurrentPlayer>,
) {
    let red = commands.spawn(Player(12)).id();
    markers[Players::Red] = red;

    let blue = commands.spawn(Player(7)).id();
    markers[Players::Blue] = blue;

    **current = blue;
}

fn get_red_player(mut query: Query<&mut Player>, markers: Marker<Players>) {
    if let Ok(mut player) = query.get_mut(markers[Players::Red]) {
        player.0 = 15;
    }
}

fn get_current_player(mut query: Query<&mut Player>, current: Marker<CurrentPlayer>) {
    if let Ok(mut player) = query.get_mut(**current) {
        player.0 = 2;
    }
}

License

• MIT License (LICENSE-MIT or http://opensource.org/licenses/MIT)
• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)

at your option.