Struct World 

pub struct World { /* private fields */ }

The World contains all entities and components, it is queryable using Queryable

Implementations

impl World

pub fn new() -> Self

Create a new World

Examples found in repository

examples/world.rs (line 16)

fn main() {
    let mut world = World::new();

    // "spawn" / create a new entity
    let entity_id = world.spawn();

    // add an component to the entity
    world.add(entity_id, Point(16, 8));

    // add multiple components at once
    world.add(entity_id, (Count(32), Tag));

    // remove the `Tag` component
    world.del::<Tag>(entity_id);

    // returns whether an entity has a component
    world.has::<Point>(entity_id); // true

    // there are also `*_res` functions for singletons
    // (single components not associated with any entity)
}

examples/query.rs (line 19)

fn main() {
    let mut world = World::new();

    for i in 0..5 {
        let ent = world.spawn();

        world.add(ent, Tag);
        world.add(ent, Name("Object"));

        if i % 2 == 0 {
            world.add(ent, Num(i));
        }
    }

    {
        let ent = world.spawn();
        world.add(ent, Num(1337));
    }

    /// Query with component tuple
    let query = world.query::<(Tag, Num)>();
    for e in &query {
        println!("Entity #{e} has both `Tag` and `Num`");
    }

    /// you can also use `Exclude` to ensure some components are not included
    for e in &world.query::<(Tag, Exclude<(Num,)>)>() {
        println!("Entity #{e} has `Tag` without `Num`");
    }

    // `Filter` allows for more fine-grained control.
    // In fact, the (Component1, Component2, ...) tuple implements `ToFilter` so it can be used in a query
    //
    // `ComponentKey` is used to identify component types,
    // the `component_id` macro can be used as a shorthand to `ComponentKey` functions.
    let filter = Filter::new()
        .with_include(&[ComponentKey::of::<Tag>(), ComponentKey::of::<Name>()])
        .with_exclude(&[component_id!(Num)]);

    for _ in &world.query_filter(filter) {
        // do stuff
    }
}

pub fn spawn(&mut self) -> Entity

Create an entity

Examples found in repository

examples/world.rs (line 19)

fn main() {
    let mut world = World::new();

    // "spawn" / create a new entity
    let entity_id = world.spawn();

    // add an component to the entity
    world.add(entity_id, Point(16, 8));

    // add multiple components at once
    world.add(entity_id, (Count(32), Tag));

    // remove the `Tag` component
    world.del::<Tag>(entity_id);

    // returns whether an entity has a component
    world.has::<Point>(entity_id); // true

    // there are also `*_res` functions for singletons
    // (single components not associated with any entity)
}

examples/query.rs (line 22)

fn main() {
    let mut world = World::new();

    for i in 0..5 {
        let ent = world.spawn();

        world.add(ent, Tag);
        world.add(ent, Name("Object"));

        if i % 2 == 0 {
            world.add(ent, Num(i));
        }
    }

    {
        let ent = world.spawn();
        world.add(ent, Num(1337));
    }

    /// Query with component tuple
    let query = world.query::<(Tag, Num)>();
    for e in &query {
        println!("Entity #{e} has both `Tag` and `Num`");
    }

    /// you can also use `Exclude` to ensure some components are not included
    for e in &world.query::<(Tag, Exclude<(Num,)>)>() {
        println!("Entity #{e} has `Tag` without `Num`");
    }

    // `Filter` allows for more fine-grained control.
    // In fact, the (Component1, Component2, ...) tuple implements `ToFilter` so it can be used in a query
    //
    // `ComponentKey` is used to identify component types,
    // the `component_id` macro can be used as a shorthand to `ComponentKey` functions.
    let filter = Filter::new()
        .with_include(&[ComponentKey::of::<Tag>(), ComponentKey::of::<Name>()])
        .with_exclude(&[component_id!(Num)]);

    for _ in &world.query_filter(filter) {
        // do stuff
    }
}

pub fn despawn(&mut self, entity: Entity)

Destroy an entity

pub fn add<B: Bundle>(&mut self, entity: Entity, bundle: B)

Add a component to an entity

Examples found in repository

examples/world.rs (line 22)

fn main() {
    let mut world = World::new();

    // "spawn" / create a new entity
    let entity_id = world.spawn();

    // add an component to the entity
    world.add(entity_id, Point(16, 8));

    // add multiple components at once
    world.add(entity_id, (Count(32), Tag));

    // remove the `Tag` component
    world.del::<Tag>(entity_id);

    // returns whether an entity has a component
    world.has::<Point>(entity_id); // true

    // there are also `*_res` functions for singletons
    // (single components not associated with any entity)
}

examples/query.rs (line 24)

fn main() {
    let mut world = World::new();

    for i in 0..5 {
        let ent = world.spawn();

        world.add(ent, Tag);
        world.add(ent, Name("Object"));

        if i % 2 == 0 {
            world.add(ent, Num(i));
        }
    }

    {
        let ent = world.spawn();
        world.add(ent, Num(1337));
    }

    /// Query with component tuple
    let query = world.query::<(Tag, Num)>();
    for e in &query {
        println!("Entity #{e} has both `Tag` and `Num`");
    }

    /// you can also use `Exclude` to ensure some components are not included
    for e in &world.query::<(Tag, Exclude<(Num,)>)>() {
        println!("Entity #{e} has `Tag` without `Num`");
    }

    // `Filter` allows for more fine-grained control.
    // In fact, the (Component1, Component2, ...) tuple implements `ToFilter` so it can be used in a query
    //
    // `ComponentKey` is used to identify component types,
    // the `component_id` macro can be used as a shorthand to `ComponentKey` functions.
    let filter = Filter::new()
        .with_include(&[ComponentKey::of::<Tag>(), ComponentKey::of::<Name>()])
        .with_exclude(&[component_id!(Num)]);

    for _ in &world.query_filter(filter) {
        // do stuff
    }
}

pub fn has<C: Component>(&self, entity: Entity) -> bool

Check if entity has component C

Examples found in repository

examples/world.rs (line 31)

fn main() {
    let mut world = World::new();

    // "spawn" / create a new entity
    let entity_id = world.spawn();

    // add an component to the entity
    world.add(entity_id, Point(16, 8));

    // add multiple components at once
    world.add(entity_id, (Count(32), Tag));

    // remove the `Tag` component
    world.del::<Tag>(entity_id);

    // returns whether an entity has a component
    world.has::<Point>(entity_id); // true

    // there are also `*_res` functions for singletons
    // (single components not associated with any entity)
}

pub fn has_key(&self, entity: Entity, key: &ComponentKey) -> bool

Same as Self::has but uses a ComponentKey

pub fn get<C: Component>(&self, entity: Entity) -> Option<&C>

Get a reference to the component of an entity

pub fn get_mut<C: Component>(&mut self, entity: Entity) -> Option<&mut C>

Get a mutable reference to the component of an entity

pub fn del<C: Component>(&mut self, entity: Entity) -> Option<Box<C>>

Remove a component from an entity

Examples found in repository

examples/world.rs (line 28)

fn main() {
    let mut world = World::new();

    // "spawn" / create a new entity
    let entity_id = world.spawn();

    // add an component to the entity
    world.add(entity_id, Point(16, 8));

    // add multiple components at once
    world.add(entity_id, (Count(32), Tag));

    // remove the `Tag` component
    world.del::<Tag>(entity_id);

    // returns whether an entity has a component
    world.has::<Point>(entity_id); // true

    // there are also `*_res` functions for singletons
    // (single components not associated with any entity)
}

pub fn add_res<C: Component>(&mut self, resource: C)

Add a global resource

A resource is like a component but it behaves like a singleton. There can only be one type of a resource at a time.

Anything that implements Component can be used as a resource.

You cannot overwrite a resource, if you must, delete one using [Self::delete_res]

pub fn has_res<C: Component>(&self) -> bool

Similar to Self::has but for resources

pub fn has_res_key(&self, key: &ComponentKey) -> bool

Same as Self::has_res but uses a ComponentKey

pub fn get_res<C: Component>(&self) -> Option<&C>

Get a reference to a global resource

For more on resources see Self::add_res

pub fn get_res_mut<C: Component>(&mut self) -> Option<&mut C>

Get a mutable reference to a global resource

For more on resources see Self::add_res

pub fn del_res<C: Component>(&mut self) -> Option<Box<C>>

Remove a global resource

Trait Implementations

impl Default for World

fn default() -> Self

Returns the “default value” for a type.

impl Queryable for World

fn query_filter(&self, filters: impl IntoFilter) -> Query

Run the query with filters

fn query_all(&self) -> Query

Query for every entity

fn query<T: ToFilter>(&self) -> Query

Run the query with filters T