Struct bevy::ecs::change_detection::ResMut
pub struct ResMut<'a, T>where
T: Resource + ?Sized,{ /* private fields */ }
Expand description
Unique mutable borrow of a Resource
.
See the Resource
documentation for usage.
If you need a shared borrow, use Res
instead.
Panics
Panics when used as a SystemParam
if the resource does not exist.
Use Option<ResMut<T>>
instead if the resource might not always exist.
Implementations§
§impl<'a, T> ResMut<'a, T>where
T: Resource + ?Sized,
impl<'a, T> ResMut<'a, T>where T: Resource + ?Sized,
pub fn into_inner(self) -> &'a mut T
pub fn into_inner(self) -> &'a mut T
Consume self
and return a mutable reference to the
contained value while marking self
as “changed”.
pub fn reborrow(&mut self) -> Mut<'_, T>
pub fn reborrow(&mut self) -> Mut<'_, T>
Returns a Mut<>
with a smaller lifetime.
This is useful if you have &mut ResMut <T>
, but you need a Mut<T>
.
pub fn map_unchanged<U>(self, f: impl FnOnce(&mut T) -> &mut U) -> Mut<'a, U>where
U: ?Sized,
pub fn map_unchanged<U>(self, f: impl FnOnce(&mut T) -> &mut U) -> Mut<'a, U>where U: ?Sized,
Maps to an inner value by applying a function to the contained reference, without flagging a change.
You should never modify the argument passed to the closure – if you want to modify the data
without flagging a change, consider using DetectChangesMut::bypass_change_detection
to make your intent explicit.
// When run, zeroes the translation of every entity.
fn reset_positions(mut transforms: Query<&mut Transform>) {
for transform in &mut transforms {
// We pinky promise not to modify `t` within the closure.
// Breaking this promise will result in logic errors, but will never cause undefined behavior.
let mut translation = transform.map_unchanged(|t| &mut t.translation);
// Only reset the translation if it isn't already zero;
translation.set_if_neq(Vec2::ZERO);
}
}
Trait Implementations§
§impl<'a, T> DetectChanges for ResMut<'a, T>where
T: Resource + ?Sized,
impl<'a, T> DetectChanges for ResMut<'a, T>where T: Resource + ?Sized,
§fn is_changed(&self) -> bool
fn is_changed(&self) -> bool
true
if this value was added or mutably dereferenced after the system last ran.§fn last_changed(&self) -> u32
fn last_changed(&self) -> u32
§impl<'a, T> DetectChangesMut for ResMut<'a, T>where
T: Resource + ?Sized,
impl<'a, T> DetectChangesMut for ResMut<'a, T>where T: Resource + ?Sized,
§fn set_changed(&mut self)
fn set_changed(&mut self)
§fn set_last_changed(&mut self, last_changed: u32)
fn set_last_changed(&mut self, last_changed: u32)
§fn bypass_change_detection(
&mut self
) -> &mut <ResMut<'a, T> as DetectChangesMut>::Inner
fn bypass_change_detection( &mut self ) -> &mut <ResMut<'a, T> as DetectChangesMut>::Inner
§impl<'w, 'a, T> IntoIterator for &'a ResMut<'w, T>where
T: Resource,
&'a T: IntoIterator,
impl<'w, 'a, T> IntoIterator for &'a ResMut<'w, T>where T: Resource, &'a T: IntoIterator,
§impl<'w, 'a, T> IntoIterator for &'a mut ResMut<'w, T>where
T: Resource,
&'a mut T: IntoIterator,
impl<'w, 'a, T> IntoIterator for &'a mut ResMut<'w, T>where T: Resource, &'a mut T: IntoIterator,
§type Item = <&'a mut T as IntoIterator>::Item
type Item = <&'a mut T as IntoIterator>::Item
§type IntoIter = <&'a mut T as IntoIterator>::IntoIter
type IntoIter = <&'a mut T as IntoIterator>::IntoIter
§impl<'a, T> SystemParam for ResMut<'a, T>where
T: Resource,
impl<'a, T> SystemParam for ResMut<'a, T>where T: Resource,
§type State = ComponentId
type State = ComponentId
§type Item = ResMut<'w, T>
type Item = ResMut<'w, T>
Self
, instantiated with new lifetimes. Read more§fn init_state(
world: &mut World,
system_meta: &mut SystemMeta
) -> <ResMut<'a, T> as SystemParam>::State
fn init_state( world: &mut World, system_meta: &mut SystemMeta ) -> <ResMut<'a, T> as SystemParam>::State
World
access used by this SystemParam
and creates a new instance of this param’s State
.§unsafe fn get_param<'w, 's>(
_: &'s mut <ResMut<'a, T> as SystemParam>::State,
system_meta: &SystemMeta,
world: &'w World,
change_tick: u32
) -> <ResMut<'a, T> as SystemParam>::Item<'w, 's>
unsafe fn get_param<'w, 's>( _: &'s mut <ResMut<'a, T> as SystemParam>::State, system_meta: &SystemMeta, world: &'w World, change_tick: u32 ) -> <ResMut<'a, T> as SystemParam>::Item<'w, 's>
§fn new_archetype(
_state: &mut Self::State,
_archetype: &Archetype,
_system_meta: &mut SystemMeta
)
fn new_archetype( _state: &mut Self::State, _archetype: &Archetype, _system_meta: &mut SystemMeta )
Archetype
, registers the components accessed by this SystemParam
(if applicable).§fn apply(state: &mut Self::State, system_meta: &SystemMeta, world: &mut World)
fn apply(state: &mut Self::State, system_meta: &SystemMeta, world: &mut World)
SystemParam
’s state.
This is used to apply Commands
during apply_system_buffers
.Auto Trait Implementations§
impl<'a, T: ?Sized> RefUnwindSafe for ResMut<'a, T>where T: RefUnwindSafe,
impl<'a, T: ?Sized> Send for ResMut<'a, T>
impl<'a, T: ?Sized> Sync for ResMut<'a, T>
impl<'a, T: ?Sized> Unpin for ResMut<'a, T>
impl<'a, T> !UnwindSafe for ResMut<'a, T>
Blanket Implementations§
§impl<T, U> AsBindGroupShaderType<U> for Twhere
U: ShaderType,
&'a T: for<'a> Into<U>,
impl<T, U> AsBindGroupShaderType<U> for Twhere U: ShaderType, &'a T: for<'a> Into<U>,
§fn as_bind_group_shader_type(&self, _images: &RenderAssets<Image>) -> U
fn as_bind_group_shader_type(&self, _images: &RenderAssets<Image>) -> U
T
ShaderType
for self
. When used in AsBindGroup
derives, it is safe to assume that all images in self
exist.§impl<T> Downcast for Twhere
T: Any,
impl<T> Downcast for Twhere T: Any,
§fn into_any(self: Box<T, Global>) -> Box<dyn Any + 'static, Global>
fn into_any(self: Box<T, Global>) -> Box<dyn Any + 'static, Global>
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
.§fn into_any_rc(self: Rc<T>) -> Rc<dyn Any + 'static>
fn into_any_rc(self: Rc<T>) -> Rc<dyn Any + 'static>
Rc<Trait>
(where Trait: Downcast
) to Rc<Any>
. Rc<Any>
can then be
further downcast
into Rc<ConcreteType>
where ConcreteType
implements Trait
.§fn as_any(&self) -> &(dyn Any + 'static)
fn as_any(&self) -> &(dyn Any + 'static)
&Trait
(where Trait: Downcast
) to &Any
. This is needed since Rust cannot
generate &Any
’s vtable from &Trait
’s.§fn as_any_mut(&mut self) -> &mut (dyn Any + 'static)
fn as_any_mut(&mut self) -> &mut (dyn Any + 'static)
&mut Trait
(where Trait: Downcast
) to &Any
. This is needed since Rust cannot
generate &mut Any
’s vtable from &mut Trait
’s.