Enum SystemStage 

pub enum SystemStage {
    Startup,
    PreUpdate,
    Update,
    PostUpdate,
    PreRender,
    AssetSync,
    AssetSyncDeps,
    Render,
    PostRender,
}

Determines when during a frame a system is executed.

Stages are iterated in the order defined here — Startup runs once during App::build, all others run every App::update tick.

Asset sync stages (AssetSync, AssetSyncDeps) run after PreRender so that the GPU backend — which is delivered in PreRender via a one-shot channel — is guaranteed to be present before asset upload is attempted.

Variants

Startup

Runs once at startup, before the main loop begins.

PreUpdate

Runs before the main update.

Update

Main game-logic update.

PostUpdate

Runs after the main update.

PreRender

Prepare rendering data and poll for the GPU backend. The backend resource becomes available here on the tick it finishes initialising, making it visible to the asset sync stages below.

AssetSync

Upload CPU-side source assets to the GPU backend. Runs after PreRender so the backend is guaranteed to be present.

AssetSyncDeps

Construct lazy GPU resources and upload assets that depend on other processed assets. Runs in a convergence loop so dependency chains (e.g. LazyResource A → LazyResource B) resolve within a single tick.

Render

Issue draw calls.

PostRender

Cleanup or post-processing after rendering.

Implementations

impl SystemStage

pub fn is_convergent(self) -> bool

Returns true for stages that are re-run until no new resources are inserted — collapsing multi-tick dependency chains into one tick.

Startup is included so a deferred or async resource producer (e.g. a background thread pool result, or a LazyResource-style startup system using Option<Res<T>> to wait) gets another pass within the same build() call rather than only running once.

Trait Implementations

impl Clone for SystemStage

fn clone(&self) -> SystemStage

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for SystemStage

impl Debug for SystemStage

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for SystemStage

impl Hash for SystemStage

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for SystemStage

fn cmp(&self, other: &SystemStage) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for SystemStage

fn eq(&self, other: &SystemStage) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl PartialOrd for SystemStage

fn partial_cmp(&self, other: &SystemStage) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl StructuralPartialEq for SystemStage