Struct ecs_observer_desc_t 

#[repr(C)]
pub struct ecs_observer_desc_t {

    pub _canary: i32,
    pub entity: ecs_entity_t,
    pub filter: ecs_filter_desc_t,
    pub events: [ecs_entity_t; 8],
    pub yield_existing: bool,
    pub callback: ecs_iter_action_t,
    pub run: ecs_run_action_t,
    pub ctx: *mut c_void,
    pub binding_ctx: *mut c_void,
    pub ctx_free: ecs_ctx_free_t,
    pub binding_ctx_free: ecs_ctx_free_t,
    pub observable: *mut ecs_poly_t,
    pub last_event_id: *mut i32,
    pub term_index: i32,
}

Used with ecs_observer_init.

\ingroup observers

Fields

_canary: i32

entity: ecs_entity_t

Existing entity to associate with observer (optional)

filter: ecs_filter_desc_t

Filter for observer

events: [ecs_entity_t; 8]

Events to observe (OnAdd, OnRemove, OnSet, UnSet)

yield_existing: bool

When observer is created, generate events from existing data. For example, EcsOnAdd Position would match all existing instances of Position. This is only supported for events that are iterable (see EcsIterable)

callback: ecs_iter_action_t

Callback to invoke on an event, invoked when the observer matches.

run: ecs_run_action_t

Callback invoked on an event. When left to NULL the default runner is used which matches the event with the observer’s filter, and calls ‘callback’ when it matches. A reason to override the run function is to improve performance, if there are more efficient way to test whether an event matches the observer than the general purpose query matcher.

ctx: *mut c_void

User context to pass to callback

binding_ctx: *mut c_void

Context to be used for language bindings

ctx_free: ecs_ctx_free_t

Callback to free ctx

binding_ctx_free: ecs_ctx_free_t

Callback to free binding_ctx

observable: *mut ecs_poly_t

Observable with which to register the observer

last_event_id: *mut i32

Optional shared last event id for multiple observers. Ensures only one of the observers with the shared id gets triggered for an event

term_index: i32

Used for internal purposes

Trait Implementations

impl Clone for ecs_observer_desc_t

fn clone(&self) -> ecs_observer_desc_t

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ecs_observer_desc_t

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

Formats the value using the given formatter.

impl Copy for ecs_observer_desc_t