Struct bevy_ecs::query::Added[][src]

pub struct Added<T>(_);
Expand description

Filter that retrieves components of type T that have been added since the last execution of this system.

This filter is useful to do one-time post-processing on components.

Because the ordering of systems can change and this filter is only effective on changes before the query executes you need to use explicit dependency ordering or ordered stages to avoid frame delays.

If instead behavior is meant to change on whether the component changed or not ChangeTrackers may be used.

Examples


fn print_add_name_component(query: Query<&Name, Added<Name>>) {
    for name in query.iter() {
        println!("Named entity created: {:?}", name)
    }
}

Trait Implementations

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