Struct rinecs::operators::ReadRef

pub struct ReadRef<'a, T: 'a + NToOneComponent, Ref: 'a + Component> { /* fields omitted */ }

Operator that matches entities that contain a component through a reference

A reference to another entity is any component that implements Deref<Target=Entity>

The first parameter to ReadRef indicates the reference component the second the referenced

#[derive(Component, Debug)]
struct Position(f32,f32);

#[derive(Component, Debug)]
struct GeometryRef(Entity);

#[derive(Component, Debug)]
struct Geometry;


let geom = world.new_entity()
    .add(Geometry)
    .build();

world.new_entity()
    .add(GeometryRef(geom))
    .add(Position(0., 0.))
    .build();

world.new_entity()
    .add(GeometryRef(geom))
    .add(Position(10., 10.))
    .build();

for (geom, pos) in entities.iter_for::<(ReadRef<GeometryRef, Geometry>, Read<Position>)>(){
    // draw geometry at position
}

Will select all entities that reference a Geometry through a GeometryRef and have a position then draw the geometry at that position.

This allow to have only one copy of the geometry that is referenced by multiple entities

When deriving Component for a tuple struct with only one element it'll also derive Deref for that element so in this case GeometryRef automatically can be used with ReadRef

Trait Implementations

impl<'a, T, Ref> UnorderedData<'a> for ReadRef<'a, T, Ref> where     T: 'a + NToOneComponentSend,     Ref: Component + Send,     <<T as Component>::Storage as Storage<'a, T>>::Get: Borrow<T>,

type Iter = ReadRefIter<'a, Self::Storage, <Ref as Component>::Storage, Ref>

type Components = Option<Ref>

type ComponentsRef = Option<<<Ref as Component>::Storage as Storage<'a, Ref>>::Get>

type Storage = StorageReadRef<'a, <T as Component>::Storage, T, <Ref as Component>::Storage, Ref>

fn components_mask(entities: Entities<'a>) -> Bitmask

fn into_iter(entities: Entities<'a>) -> Self::Iter

fn storage(entities: Entities<'a>) -> Self::Storage

impl<'a, T, Ref> ParUnorderedData<'a> for ReadRef<'a, T, Ref> where     T: 'a + NToOneComponentSend,     Ref: Component + Send,     <<T as Component>::Storage as Storage<'a, T>>::Get: Borrow<T>,

type ParIter = ReadStorageParIter<'a, Self::ComponentsRef, Self::Storage>

fn into_pariter(entities: Entities<'a>) -> Self::ParIter

impl<'a, T, Ref> UnorderedDataLocal<'a> for ReadRef<'a, T, Ref> where     T: 'a + NToOneComponentThreadLocal,     Ref: Component,     <<T as Component>::Storage as Storage<'a, T>>::Get: Borrow<T>,

type Iter = ReadRefIter<'a, Self::Storage, <Ref as Component>::Storage, Ref>

type Components = Option<Ref>

type ComponentsRef = Option<<<Ref as Component>::Storage as Storage<'a, Ref>>::Get>

type Storage = StorageReadRefLocal<'a, <T as Component>::Storage, T, <Ref as Component>::Storage, Ref>

fn components_mask_thread_local(entities: EntitiesThreadLocal<'a>) -> Bitmask

fn into_iter_thread_local(entities: EntitiesThreadLocal<'a>) -> Self::Iter

fn storage_thread_local(entities: EntitiesThreadLocal<'a>) -> Self::Storage

impl<'a, T: 'a + NToOneComponent, Ref: 'a + Component> FromComponent<'a, &'a Ref> for ReadRef<'a, T, Ref>

fn from_component(component: &'a Ref) -> ReadRef<'a, T, Ref>

impl<'a, T: 'a + NToOneComponent, Ref: 'a + Component> Deref for ReadRef<'a, T, Ref>

type Target = Ref

The resulting type after dereferencing.

fn deref(&self) -> &Ref

Dereferences the value.