pub struct LazyUpdate { /* private fields */ }
Expand description

Lazy updates can be used for world updates that need to borrow a lot of resources and as such should better be done at the end. They work lazily in the sense that they are dispatched when calling world.maintain().

Lazy updates are dispatched in the order that they are requested. Multiple updates sent from one system may be overridden by updates sent from other systems.

Please note that the provided methods take &self so there’s no need to get LazyUpdate mutably. This resource is added to the world by default.

Implementations

Lazily inserts a component for an entity.

Examples
struct Pos(f32, f32);

impl Component for Pos {
    type Storage = VecStorage<Self>;
}

struct InsertPos;

impl<'a> System<'a> for InsertPos {
    type SystemData = (Entities<'a>, Read<'a, LazyUpdate>);

    fn run(&mut self, (ent, lazy): Self::SystemData) {
        let a = ent.create();
        lazy.insert(a, Pos(1.0, 1.0));
    }
}

Lazily inserts components for entities.

Examples
struct Pos(f32, f32);

impl Component for Pos {
    type Storage = VecStorage<Self>;
}

struct InsertPos;

impl<'a> System<'a> for InsertPos {
    type SystemData = (Entities<'a>, Read<'a, LazyUpdate>);

    fn run(&mut self, (ent, lazy): Self::SystemData) {
        let a = ent.create();
        let b = ent.create();

        lazy.insert_all(vec![(a, Pos(3.0, 1.0)), (b, Pos(0.0, 4.0))]);
    }
}

Lazily removes a component.

Examples
struct Pos;

impl Component for Pos {
    type Storage = VecStorage<Self>;
}

struct RemovePos;

impl<'a> System<'a> for RemovePos {
    type SystemData = (Entities<'a>, Read<'a, LazyUpdate>);

    fn run(&mut self, (ent, lazy): Self::SystemData) {
        for entity in ent.join() {
            lazy.remove::<Pos>(entity);
        }
    }
}

Lazily executes a closure with world access.

Examples
struct Pos;

impl Component for Pos {
    type Storage = VecStorage<Self>;
}

struct Execution;

impl<'a> System<'a> for Execution {
    type SystemData = (Entities<'a>, Read<'a, LazyUpdate>);

    fn run(&mut self, (ent, lazy): Self::SystemData) {
        for entity in ent.join() {
            lazy.exec(move |world| {
                if world.is_alive(entity) {
                    println!("Entity {:?} is alive.", entity);
                }
            });
        }
    }
}

Lazily executes a closure with mutable world access.

This can be used to add a resource to the World from a system.

Examples

struct Sys;

impl<'a> System<'a> for Sys {
    type SystemData = (Entities<'a>, Read<'a, LazyUpdate>);

    fn run(&mut self, (ent, lazy): Self::SystemData) {
        for entity in ent.join() {
            lazy.exec_mut(move |world| {
                // complete extermination!
                world.delete_all();
            });
        }
    }
}

Creates a new LazyBuilder which inserts components using LazyUpdate. This means that the components won’t be available immediately, but only after a maintain on World is performed.

Examples
struct Pos(f32, f32);

impl Component for Pos {
    type Storage = VecStorage<Self>;
}

let my_entity = lazy.create_entity(&entities).with(Pos(1.0, 3.0)).build();

Trait Implementations

Returns the “default value” for a type. Read more

Executes the destructor for this type. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

The alignment of pointer.

The type for initializers.

Initializes a with the given initializer. Read more

Dereferences the given pointer. Read more

Mutably dereferences the given pointer. Read more

Drops the object pointed to by the given pointer. Read more

Tries to create the default.

Calls try_default and panics on an error case.

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.