Struct rs_ecs::QueryMap

pub struct QueryMap<'q, S>where
    S: QuerySpec,{ /* private fields */ }

Provides random access to the entities which match a certain Query.

Implementations

impl<S> QueryMap<'_, S>where S: QuerySpec,

pub fn get(&self, ent: Entity) -> Option<<S::Fetch as Fetch<'_>>::Item>where S::Fetch: FetchShared,

Access the queried components of the given Entity

Available only if the components do not include unique references.

Examples

let mut world = World::new();

let entity1 = world.alloc();
world.insert(entity1, (42_i32, 1.0_f32));

let entity2 = world.alloc();
world.insert(entity2, (23_i32,));

let mut query = Query::<(&i32, Option<&f32>)>::new();
let mut query = query.borrow(&world);
let mut query = query.map();

let (i1, f1) = query.get(entity1).unwrap();
let (i2, f2) = query.get(entity2).unwrap();

assert_eq!(*i1, 42);
assert_eq!(f1.copied(), Some(1.0));
assert_eq!(*i2, 23);
assert_eq!(f2.copied(), None);

pub fn get_mut(&mut self, ent: Entity) -> Option<<S::Fetch as Fetch<'_>>::Item>

Exclusively access the queried components of the given Entity

pub fn get_many_mut<const N: usize>( &mut self, ent: [Entity; N] ) -> [Option<<S::Fetch as Fetch<'_>>::Item>; N]

Exclusively access the queried component of the given distinct entities

Examples

let mut world = World::new();

let entity1 = world.alloc();
world.insert(entity1, (42_i32, 1.0_f32));

let entity2 = world.alloc();
world.insert(entity2, (23_i32,));

let mut query = Query::<&mut i32>::new();
let mut query = query.borrow(&world);
let mut query = query.map();

let [i1, i2] = query.get_many_mut([entity1, entity2]);

assert_eq!(*i1.unwrap(), 42);
assert_eq!(*i2.unwrap(), 23);

Trait Implementations

impl<'q, S> Send for QueryMap<'q, S>where S: QuerySpec, <S::Fetch as Fetch<'q>>::Item: Send,

impl<'q, S> Sync for QueryMap<'q, S>where S: QuerySpec, <S::Fetch as Fetch<'q>>::Item: Send,