Struct valence::ecs::reflect::ReflectMapEntities

pub struct ReflectMapEntities { /* private fields */ }

For a specific type of component, this maps any fields with values of type Entity to a new world. Since a given Entity ID is only valid for the world it came from, when performing deserialization any stored IDs need to be re-allocated in the destination world.

See SceneEntityMapper and MapEntities for more information.

Implementations

impl ReflectMapEntities

pub fn map_all_entities( &self, world: &mut World, entity_map: &mut HashMap<Entity, Entity, EntityHash>, )

A general method for applying MapEntities behavior to all elements in an EntityHashMap<Entity>.

Be mindful in its usage: Works best in situations where the entities in the EntityHashMap<Entity> are newly created, before systems have a chance to add new components. If some of the entities referred to by the EntityHashMap<Entity> might already contain valid entity references, you should use map_entities.

An example of this: A scene can be loaded with Parent components, but then a Parent component can be added to these entities after they have been loaded. If you reload the scene using map_all_entities, those Parent components with already valid entity references could be updated to point at something else entirely.

pub fn map_entities( &self, world: &mut World, entity_map: &mut HashMap<Entity, Entity, EntityHash>, entities: &[Entity], )

A general method for applying MapEntities behavior to elements in an EntityHashMap<Entity>. Unlike map_all_entities, this is applied to specific entities, not all values in the EntityHashMap<Entity>.

This is useful mostly for when you need to be careful not to update components that already contain valid entity values. See map_all_entities for more details.

Trait Implementations

impl Clone for ReflectMapEntities

fn clone(&self) -> ReflectMapEntities

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<C> FromType<C> for ReflectMapEntities

where C: Component + MapEntities,

fn from_type() -> ReflectMapEntities