Struct Context 

pub struct Context {
    pub time: Time,
    pub events: Events,
    pub globals: Globals,
    /* private fields */
}

Main context passed to all systems

Centralizes engine state

• time - Frame timing (delta, fps, frame count)
• events - Event queue for inter-system communication
• globals - Type-erased resource storage

Access via system parameter:

#[system]
fn my_system(ctx: &mut Context) {
    let delta = ctx.time.delta();

    for event in ctx.events.read::<CollisionEvent>() {
        // handle collision
    }

    let mut world = ctx.world();
    world.spawn().insert(Health(100));
}

Fields

time: Time

Frame timing information

events: Events

Event queue

globals: Globals

Shared resource storage

Implementations

impl Context

pub fn new() -> Context

Creates a new Context with empty state

pub fn quit(&mut self)

Signals the engine to stop after the current frame completes

The main loop will exit gracefully after all systems finish execution.

pub fn is_running(&self) -> bool

Returns true if the engine is still running

pub fn register<G>(&mut self, global: G)

where G: Any + Send + Sync + 'static,

Registers a global resource (shorthand for globals.register())

If a resource of this type already exists, it will be replaced.

pub fn global<G>(&self) -> Option<RefMut<'_, G>>

where G: Any + Send + Sync + 'static,

Gets a reference to a global resource

pub fn on<E>(&mut self, f: impl FnMut(&E, &mut Context))

where E: Event + Clone,

Convenience method for reading events

Example

ctx.on::<KeyboardInput>(|event, _context| {
    println!("Key: {:?}", event.key);
});

pub fn take<E>(&mut self, f: impl FnMut(E, &mut Context))

where E: Event,

Convenience method for consuming events

Example

ctx.take::<MouseButtonInput>(|event, _context| {
    handle_click(event.button);
});

Trait Implementations

impl ContextEcsExt for Context

fn world(&self) -> RefMut<'_, World>

Returns a reference to the World

Panics

Panics with a helpful message if EcsPlugin is not registered

impl ContextInputExt for Context

fn input(&self) -> RefMut<'_, Input>

Returns a reference to the Input manager

Panics

Panics with a helpful message if InputPlugin is not registered

impl ContextWindowExt for Context

fn window(&self) -> RefMut<'_, KonWindow>

impl Default for Context

fn default() -> Context

Returns the “default value” for a type.