Function ecs_run

Synopsis

#include <include/flecs/addons/system.h>

FLECS_API ecs_entity_t ecs_run(ecs_world_t *world, ecs_entity_t system, ecs_ftime_t delta_time, void *param)

Description

Run a specific system manually. This operation runs a single system manually. It is an efficient way to invoke logic on a set of entities, as manual systems are only matched to tables at creation time or after creation time, when a new table is created.

Manual systems are useful to evaluate lists of prematched entities at application defined times. Because none of the matching logic is evaluated before the system is invoked, manual systems are much more efficient than manually obtaining a list of entities and retrieving their components.

An application may pass custom data to a system through the param parameter. This data can be accessed by the system through the param member in the ecs_iter_t value that is passed to the system callback.

Any system may interrupt execution by setting the interrupted_by member in the ecs_iter_t value. This is particularly useful for manual systems, where the value of interrupted_by is returned by this operation. This, in cominbation with the param argument lets applications use manual systems to lookup entities: once the entity has been found its handle is passed to interrupted_by, which is then subsequently returned.

Parameters

world - The world.

system - The system to run.

delta_time - The time passed since the last system invocation.

param - A user-defined parameter to pass to the system.

Returns
handle to last evaluated entity if system was interrupted.

Mentioned in

Source

Line 157 in include/flecs/addons/system.h.