Struct PointerTraversal

pub struct PointerTraversal { /* private fields */ }

A traversal query (i.e. it implements Traversal) intended for use with Pointer events.

This will always traverse to the parent, if the entity being visited has one. Otherwise, it propagates to the pointer’s window and stops there.

Trait Implementations

impl QueryData for PointerTraversal

SAFETY: we assert fields are readonly below

unsafe fn fetch<'__w>( _fetch: &mut <PointerTraversal as WorldQuery>::Fetch<'__w>, _entity: Entity, _table_row: TableRow, ) -> <PointerTraversal as QueryData>::Item<'__w>

SAFETY: we call fetch for each member that implements Fetch.

const IS_READ_ONLY: bool = true

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

type ReadOnly = PointerTraversal

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

type Item<'__w> = PointerTraversalItem<'__w>

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>( item: <PointerTraversal as QueryData>::Item<'__wlong>, ) -> <PointerTraversal as QueryData>::Item<'__wshort>

where '__wlong: '__wshort,

This function manually implements subtyping for the query items.

impl<E> Traversal<Pointer<E>> for PointerTraversal

where E: Debug + Clone + Reflect,

fn traverse( item: <PointerTraversal as QueryData>::Item<'_>, pointer: &Pointer<E>, ) -> Option<Entity>

Returns the next entity to visit.

impl WorldQuery for PointerTraversal

unsafe fn set_archetype<'__w>( _fetch: &mut <PointerTraversal as WorldQuery>::Fetch<'__w>, _state: &<PointerTraversal as WorldQuery>::State, _archetype: &'__w Archetype, _table: &'__w Table, )

SAFETY: we call set_archetype for each member that implements Fetch

unsafe fn set_table<'__w>( _fetch: &mut <PointerTraversal as WorldQuery>::Fetch<'__w>, _state: &<PointerTraversal as WorldQuery>::State, _table: &'__w Table, )

SAFETY: we call set_table for each member that implements Fetch

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> = PointerTraversalFetch<'__w>

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

type State = PointerTraversalState

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>( fetch: <PointerTraversal as WorldQuery>::Fetch<'__wlong>, ) -> <PointerTraversal as WorldQuery>::Fetch<'__wshort>

where '__wlong: '__wshort,

This function manually implements subtyping for the query fetches.

unsafe fn init_fetch<'__w>( _world: UnsafeWorldCell<'__w>, state: &<PointerTraversal as WorldQuery>::State, _last_run: Tick, _this_run: Tick, ) -> <PointerTraversal as WorldQuery>::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.

fn update_component_access( state: &<PointerTraversal as WorldQuery>::State, _access: &mut FilteredAccess<ComponentId>, )

Adds any component accesses used by this WorldQuery to access.

fn init_state(world: &mut World) -> PointerTraversalState

Creates and initializes a State for this WorldQuery type.

fn get_state(components: &Components) -> Option<PointerTraversalState>

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

fn matches_component_set( state: &<PointerTraversal as WorldQuery>::State, _set_contains_id: &impl Fn(ComponentId) -> bool, ) -> bool

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

fn set_access(_state: &mut Self::State, _access: &FilteredAccess<ComponentId>)

Sets available accesses for implementors with dynamic access such as FilteredEntityRef or FilteredEntityMut.

impl ReadOnlyQueryData for PointerTraversal

SAFETY: we assert fields are readonly below