Struct World

pub struct World { /* private fields */ }

The World is the entry point to an ecs

Implementations

impl World

pub fn new() -> Self

pub fn kill(&mut self, ent_id: EntityId)

Kills an entity

This means the EntityId will be reused for other entities. This also implies that world.is_alive(the_killed_enity_id) will not be accurate. If you want to keep an id killed, use world.kill_and_keep(id). You should still free those ids using world.free_id later so that the memory can be reused.

pub fn kill_and_keep(&mut self, ent_id: EntityId)

Kills an entity without telling the ecs to reuse its id

This means that world.is_alive can be used accurately.

You should use world.free_id(the_killed_entity_id) later to reuse the memory used by the killed entity (64 bits per entity).

pub fn free_id(&mut self, ent_id: EntityId)

Frees an entity id, meaning that the world.is_alive method will no longer be accurate for this entity.

Memory used to store this entity id (64 bits) will be reused.

pub fn is_alive(&mut self, ent_id: EntityId) -> bool

Check whether an entity is alive. This can only be used accurately when world.kill_and_keep is used instead of world.kill.

pub fn entity_count(&self) -> usize

Returns the amount of entities that are alive

pub fn get_component<T: Component + 'static>(&self, entity: EntityId) -> &T

Returns the component of type T for entity with id entity.

Panics

if the component does not exist for the given entity

pub fn get_component_mut<T: Component + 'static>( &mut self, entity: EntityId, ) -> &mut T

Returns a mutable referencce to the component of type T for entity with id entity

Panics

if the component does not exist for the given entity

pub fn set_component<T: Component + 'static>( &mut self, entity: EntityId, comp: T, )

Set an entity’s component.

Panics

if the component does not exist for the given entity

pub fn has_component<C: Component>(&self, entity: EntityId) -> bool

Check whether an entity contains the given component

pub fn has_flag<F: Flag>(&self, entity: EntityId, flag: F) -> bool

Returns whether the entity has the specified flag set.

pub fn set_flag<F: Flag>(&mut self, entity: EntityId, flag: F)

Sets a flag for an entity

Always use the same enum for flags. Don’t mix flag enums, because the id of the enum variant is used to determine whether the entity has a specific flag.

pub fn unset_flag<F: Flag>(&mut self, entity: EntityId, flag: F)

Remove a flag from an entity

impl World

pub fn query_ids<'a>(&'a self) -> impl Iterator<Item = EntityId> + 'a

Query all entity ids