Struct SpawnDetails 

pub struct SpawnDetails { /* private fields */ }

The SpawnDetails query parameter fetches the Tick the entity was spawned at.

To evaluate whether the spawn happened since the last time the system ran, the system param SystemChangeTick needs to be used.

If the query should filter for spawned entities instead, use the Spawned query filter instead.

Examples

fn print_spawn_details(query: Query<(Entity, SpawnDetails)>) {
    for (entity, spawn_details) in &query {
        if spawn_details.is_spawned() {
            print!("new ");
        }
        print!(
            "entity {:?} spawned at {:?}",
            entity,
            spawn_details.spawn_tick()
        );
        match spawn_details.spawned_by().into_option() {
            Some(location) => println!(" by {:?}", location),
            None => println!()
        }
    }
}

Implementations

impl SpawnDetails

pub fn is_spawned(self) -> bool

Returns true if the entity spawned since the last time this system ran. Otherwise, returns false.

pub fn spawn_tick(self) -> Tick

Returns the Tick this entity spawned at.

pub fn spawned_by(self) -> MaybeLocation

Returns the source code location from which this entity has been spawned.

Trait Implementations

impl Clone for SpawnDetails

fn clone(&self) -> SpawnDetails

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SpawnDetails

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl QueryData for SpawnDetails

const IS_READ_ONLY: bool = true

True if this query is read-only and may not perform mutable access.

type ReadOnly = SpawnDetails

The read-only variant of this QueryData, which satisfies the ReadOnlyQueryData trait.

type Item<'w, 's> = SpawnDetails

The item returned by this WorldQuery This will be the data retrieved by the query, and is visible to the end user when calling e.g. Query<Self>::get.

fn shrink<'wlong: 'wshort, 'wshort, 's>( item: Self::Item<'wlong, 's>, ) -> Self::Item<'wshort, 's>

This function manually implements subtyping for the query items.

unsafe fn fetch<'w, 's>( _state: &'s Self::State, fetch: &mut Self::Fetch<'w>, entity: Entity, _table_row: TableRow, ) -> Self::Item<'w, 's>

Fetch Self::Item for either the given entity in the current Table, or for the given entity in the current Archetype. This must always be called after WorldQuery::set_table with a table_row in the range of the current Table or after WorldQuery::set_archetype with an entity in the current archetype. Accesses components registered in WorldQuery::update_component_access.

fn provide_extra_access( _state: &mut Self::State, _access: &mut Access, _available_access: &Access, )

Offers additional access above what we requested in update_component_access. Implementations may add additional access that is a subset of available_access and does not conflict with anything in access, and must update access to include that access.

impl ReleaseStateQueryData for SpawnDetails

fn release_state<'w>(item: Self::Item<'w, '_>) -> Self::Item<'w, 'static>

Releases the borrow from the query state by converting an item to have a 'static state lifetime.

impl WorldQuery for SpawnDetails

const IS_DENSE: bool = true

Returns true if (and only if) every table of every archetype matched by this fetch contains all of the matched components.

type Fetch<'w> = SpawnDetailsFetch<'w>

Per archetype/table state retrieved by this WorldQuery to compute Self::Item for each entity.

type State = ()

State used to construct a Self::Fetch. This will be cached inside QueryState, so it is best to move as much data / computation here as possible to reduce the cost of constructing Self::Fetch.

fn shrink_fetch<'wlong: 'wshort, 'wshort>( fetch: Self::Fetch<'wlong>, ) -> Self::Fetch<'wshort>

This function manually implements subtyping for the query fetches.

unsafe fn init_fetch<'w, 's>( world: UnsafeWorldCell<'w>, _state: &'s Self::State, last_run: Tick, this_run: Tick, ) -> Self::Fetch<'w>

Creates a new instance of Self::Fetch, by combining data from the World with the cached Self::State. Readonly accesses resources registered in WorldQuery::update_component_access.

unsafe fn set_archetype<'w, 's>( _fetch: &mut Self::Fetch<'w>, _state: &'s Self::State, _archetype: &'w Archetype, _table: &'w Table, )

Adjusts internal state to account for the next Archetype. This will always be called on archetypes that match this WorldQuery.

unsafe fn set_table<'w, 's>( _fetch: &mut Self::Fetch<'w>, _state: &'s Self::State, _table: &'w Table, )

Adjusts internal state to account for the next Table. This will always be called on tables that match this WorldQuery.

fn update_component_access(_state: &Self::State, _access: &mut FilteredAccess)

Adds any component accesses used by this WorldQuery to access.

fn init_state(_world: &mut World)

Creates and initializes a State for this WorldQuery type.

fn get_state(_components: &Components) -> Option<()>

Attempts to initialize a State for this WorldQuery type using read-only access to Components.

fn matches_component_set( _state: &Self::State, _set_contains_id: &impl Fn(ComponentId) -> bool, ) -> bool

Returns true if this query matches a set of components. Otherwise, returns false.

impl Copy for SpawnDetails

impl ReadOnlyQueryData for SpawnDetails

SAFETY: access is read only