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Helios Engine

World

RyuTribal/helios

World¶

The World class is the central container for all ECS data in Helios. It manages entities, components, resources, and events.

Methods¶

Entity Management¶

Method	Description
`spawn()`	Spawns a new entity with no components.
`spawn(Ts&&... components)`	Spawns a new entity with an initial set of components.
`spawn_with_children(F&& build_children, Ts&&... components)`	Spawns an entity and adds children to it in one call.
`spawn_child(Entity parent, Ts&&... components)`	Spawns an entity as a child of the given parent.
`despawn(Entity entity)`	Despawn an entity, removing it and all its components.
`is_alive(Entity entity)`	Checks whether an entity is still alive.

Component Access¶

Method	Description
`get<T>(Entity entity)`	Gets a mutable reference to a component (asserts if missing).
`try_get<T>(Entity entity)`	Tries to get a pointer to a component (returns `nullptr` if missing).
`has<T>(Entity entity)`	Checks whether an entity has a given component.
`add<T>(Entity entity, T component)`	Adds or overwrites a component for an entity.
`remove<T>(Entity entity)`	Removes a component from an entity.

Resources¶

Method	Description
`insert_resource<T>(T resource)`	Inserts a unique resource into the world.
`resource<T>()`	Gets a reference to a resource (asserts if missing).
`try_resource<T>()`	Tries to get a pointer to a resource (returns `nullptr` if missing).
`has_resource<T>()`	Checks whether a resource exists.

Events¶

Method	Description
`register_event<T>()`	Registers a new event type.
`event_writer<T>()`	Gets an `EventWriter` for the given event type.
`event_reader<T>()`	Gets an `EventReader` for the given event type.

Queries & Commands¶

Method	Description
`query<Params...>()`	Creates a new Query to iterate over entities matching criteria.
`pending_commands()`	Returns a reference to the world-owned pending Commands buffer.
`apply_and_clear_pending_commands()`	Applies all deferred commands and clears the buffer.

Usage Example¶

#include "helios/ecs/world.h"

helios::World world;

// Spawn an entity with components
auto entity = world.spawn(Position{0, 0}, Velocity{1, 1});

// Access components
if (auto* pos = world.try_get<Position>(entity)) {
    pos->x += 10;
}

// Manage resources
world.insert_resource(Time{0.0f});
float dt = world.resource<Time>().delta_time;