Struct SurfaceCapture 

pub struct SurfaceCapture {
    pub request: Arc<AtomicBool>,
    pub store: Arc<Mutex<Option<SurfaceFrame>>>,
    pub waker: Arc<OnceLock<EventLoopWaker>>,
}

Coordination handle for on-screen surface screenshots, inserted as a Resource into both worlds.

• The render backend inspects Self::is_requested each frame; when set, it performs a GPU->CPU readback, writes the result via Self::write, and clears the flag.
• Both fields are Arc-wrapped (Send + Sync) so MCP-server worker threads can clone the handle and read filled frames.

Fields

request: Arc<AtomicBool>

One-shot capture request flag; the renderer clears it after writing.

store: Arc<Mutex<Option<SurfaceFrame>>>

Latest captured frame; the renderer replaces it wholesale.

waker: Arc<OnceLock<EventLoopWaker>>

Optional handle to interrupt a parked platform event loop. The windowed backend wires this in crate::app::EventLoopWaker via Self::set_waker once its event-loop proxy exists; Self::request then nudges the loop so a screenshot request from the off-thread MCP server is serviced promptly instead of waiting for an unrelated OS event (the redraw scheduler otherwise leaves the loop parked, so the capture never runs and the request times out - the “no SurfaceCapture wired” failure). Shared Arc<OnceLock> so every clone - including the server thread’s - observes a waker set on any one of them.

Implementations

impl SurfaceCapture

pub fn is_requested(&self) -> bool

Returns true while a capture has been requested but not yet fulfilled.

pub fn set_waker(&self, waker: EventLoopWaker)

Installs the platform event-loop waker. First write wins (OnceLock); later calls are ignored. Idempotent and thread-safe.

pub fn request(&self)

Sets the request flag with Release ordering, then nudges the platform event loop (if Self::set_waker wired one) so a parked windowed backend wakes to service the readback this frame instead of sitting idle until the request times out. Idempotent.

pub fn clear_request(&self)

Clears the request flag with Release ordering.

pub fn write(&self, frame: SurfaceFrame)

Replaces the stored frame with frame.

pub fn read(&self) -> Option<SurfaceFrame>

Returns a clone of the latest stored frame, if any.

Trait Implementations

impl Clone for SurfaceCapture

fn clone(&self) -> SurfaceCapture

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Component for SurfaceCapture

where Self: Send + Sync + 'static,

const STORAGE_TYPE: StorageType = bevy_ecs::component::StorageType::SparseSet

A constant indicating the storage type used for this component.

type Mutability = Mutable

A marker type to assist Bevy with determining if this component is mutable, or immutable. Mutable components will have Component<Mutability = Mutable>, while immutable components will instead have Component<Mutability = Immutable>.

fn register_required_components( _requiree: ComponentId, required_components: &mut RequiredComponentsRegistrator<'_, '_>, )

Registers required components.

fn clone_behavior() -> ComponentCloneBehavior

Called when registering this component, allowing to override clone function (or disable cloning altogether) for this component.

fn relationship_accessor() -> Option<ComponentRelationshipAccessor<Self>>

Returns [ComponentRelationshipAccessor] required for working with relationships in dynamic contexts.

fn on_add() -> Option<for<'w> fn(DeferredWorld<'w>, HookContext)>

Gets the on_add [ComponentHook] for this Component if one is defined.

fn on_insert() -> Option<for<'w> fn(DeferredWorld<'w>, HookContext)>

Gets the on_insert [ComponentHook] for this Component if one is defined.

fn on_discard() -> Option<for<'w> fn(DeferredWorld<'w>, HookContext)>

Gets the on_discard [ComponentHook] for this Component if one is defined.

fn on_remove() -> Option<for<'w> fn(DeferredWorld<'w>, HookContext)>

Gets the on_remove [ComponentHook] for this Component if one is defined.

fn on_despawn() -> Option<for<'w> fn(DeferredWorld<'w>, HookContext)>

Gets the on_despawn [ComponentHook] for this Component if one is defined.

fn map_entities<E>(_this: &mut Self, _mapper: &mut E)

where E: EntityMapper,

Maps the entities on this component using the given EntityMapper. This is used to remap entities in contexts like scenes and entity cloning. When deriving Component, this is populated by annotating fields containing entities with #[entities]

impl Default for SurfaceCapture

fn default() -> SurfaceCapture

Returns the “default value” for a type.

impl Resource for SurfaceCapture

where Self: Send + Sync + 'static,