Struct bevy_ecs::change_detection::Res
source · pub struct Res<'w, T: ?Sized + Resource> { /* private fields */ }
Expand description
Shared borrow of a Resource
.
See the Resource
documentation for usage.
If you need a unique mutable borrow, use ResMut
instead.
§Panics
Panics when used as a SystemParameter
if the resource does not exist.
Use Option<Res<T>>
instead if the resource might not always exist.
Implementations§
source§impl<'w, T: Resource> Res<'w, T>
impl<'w, T: Resource> Res<'w, T>
sourcepub fn clone(this: &Self) -> Self
pub fn clone(this: &Self) -> Self
Copies a reference to a resource.
Note that unless you actually need an instance of Res<T>
, you should
prefer to just convert it to &T
which can be freely copied.
sourcepub fn into_inner(self) -> &'w T
pub fn into_inner(self) -> &'w T
Due to lifetime limitations of the Deref
trait, this method can be used to obtain a
reference of the Resource
with a lifetime bound to 'w
instead of the lifetime of the
struct itself.
Trait Implementations§
source§impl<'w, T: ?Sized + Resource> DetectChanges for Res<'w, T>
impl<'w, T: ?Sized + Resource> DetectChanges for Res<'w, T>
source§fn is_changed(&self) -> bool
fn is_changed(&self) -> bool
Returns
true
if this value was added or mutably dereferenced
either since the last time the system ran or, if the system never ran,
since the beginning of the program. Read moresource§fn last_changed(&self) -> Tick
fn last_changed(&self) -> Tick
Returns the change tick recording the time this data was most recently changed. Read more
source§impl<'w, 'a, T: Resource> IntoIterator for &'a Res<'w, T>where
&'a T: IntoIterator,
impl<'w, 'a, T: Resource> IntoIterator for &'a Res<'w, T>where
&'a T: IntoIterator,
source§impl<'a, T: Resource> SystemParam for Res<'a, T>
impl<'a, T: Resource> SystemParam for Res<'a, T>
§type State = ComponentId
type State = ComponentId
Used to store data which persists across invocations of a system.
§type Item<'w, 's> = Res<'w, T>
type Item<'w, 's> = Res<'w, T>
The item type returned when constructing this system param.
The value of this associated type should be
Self
, instantiated with new lifetimes. Read moresource§fn init_state(world: &mut World, system_meta: &mut SystemMeta) -> Self::State
fn init_state(world: &mut World, system_meta: &mut SystemMeta) -> Self::State
Registers any
World
access used by this SystemParam
and creates a new instance of this param’s State
.source§unsafe fn get_param<'w, 's>(
component_id: &'s mut Self::State,
system_meta: &SystemMeta,
world: UnsafeWorldCell<'w>,
change_tick: Tick
) -> Self::Item<'w, 's>
unsafe fn get_param<'w, 's>( component_id: &'s mut Self::State, system_meta: &SystemMeta, world: UnsafeWorldCell<'w>, change_tick: Tick ) -> Self::Item<'w, 's>
Creates a parameter to be passed into a
SystemParamFunction
. Read moresource§unsafe fn new_archetype(
state: &mut Self::State,
archetype: &Archetype,
system_meta: &mut SystemMeta
)
unsafe fn new_archetype( state: &mut Self::State, archetype: &Archetype, system_meta: &mut SystemMeta )
For the specified
Archetype
, registers the components accessed by this SystemParam
(if applicable).a Read moresource§fn apply(state: &mut Self::State, system_meta: &SystemMeta, world: &mut World)
fn apply(state: &mut Self::State, system_meta: &SystemMeta, world: &mut World)
Applies any deferred mutations stored in this
SystemParam
’s state.
This is used to apply Commands
during apply_deferred
.source§fn queue(
state: &mut Self::State,
system_meta: &SystemMeta,
world: DeferredWorld<'_>
)
fn queue( state: &mut Self::State, system_meta: &SystemMeta, world: DeferredWorld<'_> )
Queues any deferred mutations to be applied at the next
apply_deferred
.impl<'a, T: Resource> ReadOnlySystemParam for Res<'a, T>
Auto Trait Implementations§
impl<'w, T> Freeze for Res<'w, T>where
T: ?Sized,
impl<'w, T> RefUnwindSafe for Res<'w, T>where
T: RefUnwindSafe + ?Sized,
impl<'w, T> Send for Res<'w, T>where
T: ?Sized,
impl<'w, T> Sync for Res<'w, T>where
T: ?Sized,
impl<'w, T> Unpin for Res<'w, T>where
T: ?Sized,
impl<'w, T> UnwindSafe for Res<'w, T>where
T: RefUnwindSafe + ?Sized,
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 Twhere
T: Any,
impl<T> Downcast for Twhere
T: Any,
source§fn into_any(self: Box<T>) -> Box<dyn Any>
fn into_any(self: Box<T>) -> Box<dyn Any>
Convert
Box<dyn Trait>
(where Trait: Downcast
) to Box<dyn Any>
. Box<dyn Any>
can
then be further downcast
into Box<ConcreteType>
where ConcreteType
implements Trait
.source§fn into_any_rc(self: Rc<T>) -> Rc<dyn Any>
fn into_any_rc(self: Rc<T>) -> Rc<dyn Any>
Convert
Rc<Trait>
(where Trait: Downcast
) to Rc<Any>
. Rc<Any>
can then be
further downcast
into Rc<ConcreteType>
where ConcreteType
implements Trait
.source§fn as_any(&self) -> &(dyn Any + 'static)
fn as_any(&self) -> &(dyn Any + 'static)
Convert
&Trait
(where Trait: Downcast
) to &Any
. This is needed since Rust cannot
generate &Any
’s vtable from &Trait
’s.source§fn as_any_mut(&mut self) -> &mut (dyn Any + 'static)
fn as_any_mut(&mut self) -> &mut (dyn Any + 'static)
Convert
&mut Trait
(where Trait: Downcast
) to &Any
. This is needed since Rust cannot
generate &mut Any
’s vtable from &mut Trait
’s.