Struct flatbox_ecs::View
source · pub struct View<'q, Q>where
Q: Query,{ /* private fields */ }
Expand description
Provides random access to the results of a query
Implementations§
source§impl<'q, Q> View<'q, Q>where
Q: Query,
impl<'q, Q> View<'q, Q>where
Q: Query,
sourcepub fn get(&self, entity: Entity) -> Option<<Q as Query>::Item<'_>>where
Q: QueryShared,
pub fn get(&self, entity: Entity) -> Option<<Q as Query>::Item<'_>>where
Q: QueryShared,
Retrieve the query results corresponding to entity
Will yield None
if the entity does not exist or does not match the query.
Does not require exclusive access to the map, but is defined only for queries yielding only shared references.
sourcepub fn get_mut(&mut self, entity: Entity) -> Option<<Q as Query>::Item<'_>>
pub fn get_mut(&mut self, entity: Entity) -> Option<<Q as Query>::Item<'_>>
Retrieve the query results corresponding to entity
Will yield None
if the entity does not exist or does not match the query.
sourcepub unsafe fn get_unchecked(
&self,
entity: Entity
) -> Option<<Q as Query>::Item<'_>>
pub unsafe fn get_unchecked( &self, entity: Entity ) -> Option<<Q as Query>::Item<'_>>
Like get_mut
, but allows simultaneous access to multiple entities
§Safety
Must not be invoked while any unique borrow of the fetched components of entity
is live.
sourcepub fn get_mut_n<const N: usize>(
&mut self,
entities: [Entity; N]
) -> [Option<<Q as Query>::Item<'_>>; N]
pub fn get_mut_n<const N: usize>( &mut self, entities: [Entity; N] ) -> [Option<<Q as Query>::Item<'_>>; N]
Like get_mut
, but allows checked simultaneous access to multiple entities
For N > 3, the check for distinct entities will clone the array and take O(N log N) time.
§Examples
let mut world = World::new();
let a = world.spawn((1, 1.0));
let b = world.spawn((2, 4.0));
let c = world.spawn((3, 9.0));
let mut query = world.query_mut::<&mut i32>();
let mut view = query.view();
let [a,b,c] = view.get_mut_n([a, b, c]);
assert_eq!(*a.unwrap(), 1);
assert_eq!(*b.unwrap(), 2);
assert_eq!(*c.unwrap(), 3);
Trait Implementations§
Auto Trait Implementations§
impl<'q, Q> Freeze for View<'q, Q>
impl<'q, Q> RefUnwindSafe for View<'q, Q>
impl<'q, Q> Unpin for View<'q, Q>
impl<'q, Q> UnwindSafe for View<'q, Q>
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
source§impl<T> Downcast for T
impl<T> Downcast for T
source§impl<T> Pointable for T
impl<T> Pointable for T
source§impl<SS, SP> SupersetOf<SS> for SPwhere
SS: SubsetOf<SP>,
impl<SS, SP> SupersetOf<SS> for SPwhere
SS: SubsetOf<SP>,
source§fn to_subset(&self) -> Option<SS>
fn to_subset(&self) -> Option<SS>
The inverse inclusion map: attempts to construct
self
from the equivalent element of its
superset. Read moresource§fn is_in_subset(&self) -> bool
fn is_in_subset(&self) -> bool
Checks if
self
is actually part of its subset T
(and can be converted to it).source§fn to_subset_unchecked(&self) -> SS
fn to_subset_unchecked(&self) -> SS
Use with care! Same as
self.to_subset
but without any property checks. Always succeeds.source§fn from_subset(element: &SS) -> SP
fn from_subset(element: &SS) -> SP
The inclusion map: converts
self
to the equivalent element of its superset.