Struct MeshesToReextractNextFrame 

pub struct MeshesToReextractNextFrame(/* private fields */);

Holds a list of meshes that couldn’t be extracted this frame because their materials weren’t prepared yet.

On subsequent frames, we try to reextract those meshes.

Methods from Deref<Target = HashSet<MainEntity, EntityHash>>

pub fn capacity(&self) -> usize

Returns the number of elements the set can hold without reallocating.

Refer to capacity for further details.

Examples

let map = HashSet::with_capacity(5);

assert!(map.capacity() >= 5);

pub fn iter(&self) -> Iter<'_, T>

An iterator visiting all elements in arbitrary order. The iterator element type is &'a T.

Refer to iter for further details.

Examples

let mut map = HashSet::new();

map.insert("foo");
map.insert("bar");
map.insert("baz");

for value in map.iter() {
    // "foo", "bar", "baz"
    // Note that the above order is not guaranteed
}

pub fn len(&self) -> usize

Returns the number of elements in the set.

Refer to len for further details.

Examples

let mut map = HashSet::new();

assert_eq!(map.len(), 0);

map.insert("foo");

assert_eq!(map.len(), 1);

pub fn is_empty(&self) -> bool

Returns true if the set contains no elements.

Refer to is_empty for further details.

Examples

let mut map = HashSet::new();

assert!(map.is_empty());

map.insert("foo");

assert!(!map.is_empty());

pub fn drain(&mut self) -> Drain<'_, T>

Clears the set, returning all elements in an iterator.

Refer to drain for further details.

Examples

let mut map = HashSet::new();

map.insert("foo");
map.insert("bar");
map.insert("baz");

for value in map.drain() {
    // "foo", "bar", "baz"
    // Note that the above order is not guaranteed
}

assert!(map.is_empty());

pub fn retain<F>(&mut self, f: F)

where F: FnMut(&T) -> bool,

Retains only the elements specified by the predicate.

Refer to retain for further details.

Examples

let mut map = HashSet::new();

map.insert("foo");
map.insert("bar");
map.insert("baz");

map.retain(|value| *value == "baz");

assert_eq!(map.len(), 1);

pub fn extract_if<F>(&mut self, f: F) -> ExtractIf<'_, T, F>

where F: FnMut(&T) -> bool,

Drains elements which are true under the given predicate, and returns an iterator over the removed items.

Refer to extract_if for further details.

Examples

let mut map = HashSet::new();

map.insert("foo");
map.insert("bar");
map.insert("baz");

let extracted = map
    .extract_if(|value| *value == "baz")
    .collect::<Vec<_>>();

assert_eq!(map.len(), 2);
assert_eq!(extracted.len(), 1);

pub fn clear(&mut self)

Clears the set, removing all values.

Refer to clear for further details.

Examples

let mut map = HashSet::new();

map.insert("foo");
map.insert("bar");
map.insert("baz");

map.clear();

assert!(map.is_empty());

Examples found in repository

examples/ui/navigation/directional_navigation.rs (line 315)

fn process_inputs(
    mut action_state: ResMut<ActionState>,
    keyboard_input: Res<ButtonInput<KeyCode>>,
    gamepad_input: Query<&Gamepad>,
) {
    action_state.pressed_actions.clear();

    for action in DirectionalNavigationAction::variants() {
        if keyboard_input.just_pressed(action.keycode()) {
            action_state.pressed_actions.insert(action);
        }
    }

    for gamepad in gamepad_input.iter() {
        for action in DirectionalNavigationAction::variants() {
            if gamepad.just_pressed(action.gamepad_button()) {
                action_state.pressed_actions.insert(action);
            }
        }
    }
}

examples/ui/navigation/directional_navigation_overrides.rs (line 687)

fn process_inputs(
    mut action_state: ResMut<ActionState>,
    keyboard_input: Res<ButtonInput<KeyCode>>,
    gamepad_input: Query<&Gamepad>,
) {
    action_state.pressed_actions.clear();

    for action in DirectionalNavigationAction::variants() {
        if keyboard_input.just_pressed(action.keycode()) {
            action_state.pressed_actions.insert(action);
        }
    }

    for gamepad in gamepad_input.iter() {
        for action in DirectionalNavigationAction::variants() {
            if gamepad.just_pressed(action.gamepad_button()) {
                action_state.pressed_actions.insert(action);
            }
        }
    }
}

examples/shader_advanced/custom_render_phase.rs (line 505)

fn extract_camera_phases(
    mut stencil_phases: ResMut<ViewSortedRenderPhases<Stencil3d>>,
    cameras: Extract<Query<(Entity, &Camera), With<Camera3d>>>,
    mut live_entities: Local<HashSet<RetainedViewEntity>>,
) {
    live_entities.clear();
    for (main_entity, camera) in &cameras {
        if !camera.is_active {
            continue;
        }
        // This is the main camera, so we use the first subview index (0)
        let retained_view_entity = RetainedViewEntity::new(main_entity.into(), None, 0);

        stencil_phases.prepare_for_new_frame(retained_view_entity);
        live_entities.insert(retained_view_entity);
    }

    // Clear out all dead views.
    stencil_phases.retain(|camera_entity, _| live_entities.contains(camera_entity));
}

pub fn hasher(&self) -> &S

Returns a reference to the set’s BuildHasher.

Refer to hasher for further details.

pub fn reserve(&mut self, additional: usize)

Reserves capacity for at least additional more elements to be inserted in the HashSet. The collection may reserve more space to avoid frequent reallocations.

Refer to reserve for further details.

Examples

let mut map = HashSet::with_capacity(5);

assert!(map.capacity() >= 5);

map.reserve(10);

assert!(map.capacity() - map.len() >= 10);

pub fn try_reserve(&mut self, additional: usize) -> Result<(), TryReserveError>

Tries to reserve capacity for at least additional more elements to be inserted in the given HashSet<K,V>. The collection may reserve more space to avoid frequent reallocations.

Refer to try_reserve for further details.

Examples

let mut map = HashSet::with_capacity(5);

assert!(map.capacity() >= 5);

map.try_reserve(10).expect("Out of Memory!");

assert!(map.capacity() - map.len() >= 10);

pub fn shrink_to_fit(&mut self)

Shrinks the capacity of the set as much as possible. It will drop down as much as possible while maintaining the internal rules and possibly leaving some space in accordance with the resize policy.

Refer to shrink_to_fit for further details.

Examples

let mut map = HashSet::with_capacity(5);

map.insert("foo");
map.insert("bar");
map.insert("baz");

assert!(map.capacity() >= 5);

map.shrink_to_fit();

assert_eq!(map.capacity(), 3);

pub fn shrink_to(&mut self, min_capacity: usize)

Shrinks the capacity of the set with a lower limit. It will drop down no lower than the supplied limit while maintaining the internal rules and possibly leaving some space in accordance with the resize policy.

Refer to shrink_to for further details.

pub fn difference<'a>( &'a self, other: &'a HashSet<T, S>, ) -> Difference<'a, T, S>

Visits the values representing the difference, i.e., the values that are in self but not in other.

Refer to difference for further details.

pub fn symmetric_difference<'a>( &'a self, other: &'a HashSet<T, S>, ) -> SymmetricDifference<'a, T, S>

Visits the values representing the symmetric difference, i.e., the values that are in self or in other but not in both.

Refer to symmetric_difference for further details.

pub fn intersection<'a>( &'a self, other: &'a HashSet<T, S>, ) -> Intersection<'a, T, S>

Visits the values representing the intersection, i.e., the values that are both in self and other.

Refer to intersection for further details.

pub fn union<'a>(&'a self, other: &'a HashSet<T, S>) -> Union<'a, T, S>

Visits the values representing the union, i.e., all the values in self or other, without duplicates.

Refer to union for further details.

pub fn contains<Q>(&self, value: &Q) -> bool

where Q: Hash + Equivalent<T> + ?Sized,

Returns true if the set contains a value.

Refer to contains for further details.

Examples

let mut map = HashSet::new();

map.insert("foo");

assert!(map.contains("foo"));

Examples found in repository

examples/gltf/gltf_extension_animation_graph.rs (line 251)

    fn on_gltf_node(
        &mut self,
        _load_context: &mut LoadContext<'_>,
        gltf_node: &gltf::Node,
        entity: &mut EntityWorldMut,
    ) {
        if self.animation_root_indices.contains(&gltf_node.index()) {
            self.animation_root_entities.insert(entity.id());
        }
    }

examples/shader_advanced/custom_render_phase.rs (line 518)

fn extract_camera_phases(
    mut stencil_phases: ResMut<ViewSortedRenderPhases<Stencil3d>>,
    cameras: Extract<Query<(Entity, &Camera), With<Camera3d>>>,
    mut live_entities: Local<HashSet<RetainedViewEntity>>,
) {
    live_entities.clear();
    for (main_entity, camera) in &cameras {
        if !camera.is_active {
            continue;
        }
        // This is the main camera, so we use the first subview index (0)
        let retained_view_entity = RetainedViewEntity::new(main_entity.into(), None, 0);

        stencil_phases.prepare_for_new_frame(retained_view_entity);
        live_entities.insert(retained_view_entity);
    }

    // Clear out all dead views.
    stencil_phases.retain(|camera_entity, _| live_entities.contains(camera_entity));
}

examples/testbed/helpers.rs (line 26)

pub fn switch_scene_in_ci<Scene: States + FreelyMutableState + Next>(
    mut ci_config: ResMut<CiTestingConfig>,
    scene: Res<State<Scene>>,
    mut next_scene: ResMut<NextState<Scene>>,
    mut scenes_visited: Local<HashSet<Scene>>,
    frame_count: Res<FrameCount>,
    captured: RemovedComponents<Captured>,
) {
    if scene.is_changed() {
        // Changed scene! trigger a screenshot in 100 frames
        ci_config.events.push(CiTestingEventOnFrame(
            frame_count.0 + 100,
            CiTestingEvent::NamedScreenshot(format!("{:?}", scene.get())),
        ));
        if scenes_visited.contains(scene.get()) {
            // Exit once all scenes have been screenshotted
            ci_config.events.push(CiTestingEventOnFrame(
                frame_count.0 + 1,
                CiTestingEvent::AppExit,
            ));
        }
        return;
    }

    if !captured.is_empty() {
        // Screenshot taken! Switch to the next scene
        scenes_visited.insert(scene.get().clone());
        next_scene.set(scene.get().next());
    }
}

examples/shader_advanced/compute_mesh.rs (line 194)

fn prepare_chunks(
    meshes_to_generate: Query<&GenerateMesh>,
    mut chunks: ResMut<ChunksToProcess>,
    pipeline_cache: Res<PipelineCache>,
    pipeline: Res<ComputePipeline>,
    mut processed: Local<HashSet<AssetId<Mesh>>>,
) {
    // If the pipeline isn't ready, then meshes
    // won't be processed. So we want to wait until
    // the pipeline is ready before considering any mesh processed.
    if pipeline_cache
        .get_compute_pipeline(pipeline.pipeline)
        .is_some()
    {
        // get the AssetId for each Handle<Mesh>
        // which we'll use later to get the relevant buffers
        // from the mesh_allocator
        let chunk_data: Vec<AssetId<Mesh>> = meshes_to_generate
            .iter()
            .filter_map(|gmesh| {
                let id = gmesh.0.id();
                processed.contains(&id).not().then_some(id)
            })
            .collect();

        // Cache any meshes we're going to process this frame
        for id in &chunk_data {
            processed.insert(*id);
        }

        chunks.0 = chunk_data;
    }
}

examples/ui/navigation/directional_navigation.rs (line 338)

fn navigate(
    action_state: Res<ActionState>,
    mut auto_directional_navigator: AutoDirectionalNavigator,
) {
    let net_east_west = action_state
        .pressed_actions
        .contains(&DirectionalNavigationAction::Right) as i8
        - action_state
            .pressed_actions
            .contains(&DirectionalNavigationAction::Left) as i8;

    let net_north_south = action_state
        .pressed_actions
        .contains(&DirectionalNavigationAction::Up) as i8
        - action_state
            .pressed_actions
            .contains(&DirectionalNavigationAction::Down) as i8;

    // Use Dir2::from_xy to convert input to direction, then convert to CompassOctant
    let maybe_direction = Dir2::from_xy(net_east_west as f32, net_north_south as f32)
        .ok()
        .map(CompassOctant::from);

    if let Some(direction) = maybe_direction {
        match auto_directional_navigator.navigate(direction) {
            Ok(_entity) => {
                // Successfully navigated
            }
            Err(_e) => {
                // Navigation failed (no neighbor in that direction)
            }
        }
    }
}

fn update_focus_display(
    input_focus: Res<InputFocus>,
    button_query: Query<&Name, With<Button>>,
    mut display_query: Query<&mut Text, With<FocusDisplay>>,
) {
    if let Ok(mut text) = display_query.single_mut() {
        if let Some(focused_entity) = input_focus.get() {
            if let Ok(name) = button_query.get(focused_entity) {
                **text = format!("Focused: {}", name);
            } else {
                **text = "Focused: Unknown".to_string();
            }
        } else {
            **text = "Focused: None".to_string();
        }
    }
}

fn update_key_display(
    keyboard_input: Res<ButtonInput<KeyCode>>,
    gamepad_input: Query<&Gamepad>,
    mut display_query: Query<&mut Text, With<KeyDisplay>>,
) {
    if let Ok(mut text) = display_query.single_mut() {
        // Check for keyboard inputs
        for action in DirectionalNavigationAction::variants() {
            if keyboard_input.just_pressed(action.keycode()) {
                let key_name = match action {
                    DirectionalNavigationAction::Up => "Up Arrow",
                    DirectionalNavigationAction::Down => "Down Arrow",
                    DirectionalNavigationAction::Left => "Left Arrow",
                    DirectionalNavigationAction::Right => "Right Arrow",
                    DirectionalNavigationAction::Select => "Enter",
                };
                **text = format!("Last Key: {}", key_name);
                return;
            }
        }

        // Check for gamepad inputs
        for gamepad in gamepad_input.iter() {
            for action in DirectionalNavigationAction::variants() {
                if gamepad.just_pressed(action.gamepad_button()) {
                    let button_name = match action {
                        DirectionalNavigationAction::Up => "D-Pad Up",
                        DirectionalNavigationAction::Down => "D-Pad Down",
                        DirectionalNavigationAction::Left => "D-Pad Left",
                        DirectionalNavigationAction::Right => "D-Pad Right",
                        DirectionalNavigationAction::Select => "A Button",
                    };
                    **text = format!("Last Key: {}", button_name);
                    return;
                }
            }
        }
    }
}

fn highlight_focused_element(
    input_focus: Res<InputFocus>,
    input_focus_visible: Res<InputFocusVisible>,
    mut query: Query<(Entity, &mut BorderColor)>,
) {
    for (entity, mut border_color) in query.iter_mut() {
        if input_focus.get() == Some(entity) && input_focus_visible.0 {
            *border_color = BorderColor::all(FOCUSED_BORDER);
        } else {
            *border_color = BorderColor::DEFAULT;
        }
    }
}

fn interact_with_focused_button(
    action_state: Res<ActionState>,
    input_focus: Res<InputFocus>,
    mut commands: Commands,
) {
    if action_state
        .pressed_actions
        .contains(&DirectionalNavigationAction::Select)
        && let Some(focused_entity) = input_focus.get()
    {
        commands.trigger(Pointer::new(
            PointerId::Mouse,
            Location {
                target: NormalizedRenderTarget::None {
                    width: 0,
                    height: 0,
                },
                position: Vec2::ZERO,
            },
            Click {
                button: PointerButton::Primary,
                hit: HitData {
                    camera: Entity::PLACEHOLDER,
                    depth: 0.0,
                    position: None,
                    normal: None,
                    extra: None,
                },
                count: 1,
                duration: Duration::from_secs_f32(0.1),
            },
            focused_entity,
        ));
    }
}

examples/ui/navigation/directional_navigation_overrides.rs (line 712)

fn navigate(
    action_state: Res<ActionState>,
    parent_query: Query<&ChildOf>,
    mut visibility_query: Query<&mut Visibility>,
    mut auto_directional_navigator: AutoDirectionalNavigator,
) {
    let net_east_west = action_state
        .pressed_actions
        .contains(&DirectionalNavigationAction::Right) as i8
        - action_state
            .pressed_actions
            .contains(&DirectionalNavigationAction::Left) as i8;

    let net_north_south = action_state
        .pressed_actions
        .contains(&DirectionalNavigationAction::Up) as i8
        - action_state
            .pressed_actions
            .contains(&DirectionalNavigationAction::Down) as i8;

    // Use Dir2::from_xy to convert input to direction, then convert to CompassOctant
    let maybe_direction = Dir2::from_xy(net_east_west as f32, net_north_south as f32)
        .ok()
        .map(CompassOctant::from);

    // Store the previous focus in case navigation switches pages.
    let previous_focus = auto_directional_navigator.input_focus();
    if let Some(direction) = maybe_direction {
        match auto_directional_navigator.navigate(direction) {
            Ok(new_focus) => {
                // Successfully navigated!

                // If navigation switches between pages, change the visibilities of pages
                if let Ok(current_child_of) = parent_query.get(new_focus)
                    && let Ok(mut current_page_visibility) =
                        visibility_query.get_mut(current_child_of.parent())
                {
                    *current_page_visibility = Visibility::Visible;

                    if let Some(previous_focus_entity) = previous_focus
                        && let Ok(previous_child_of) = parent_query.get(previous_focus_entity)
                        && previous_child_of.parent() != current_child_of.parent()
                        && let Ok(mut previous_page_visibility) =
                            visibility_query.get_mut(previous_child_of.parent())
                    {
                        *previous_page_visibility = Visibility::Hidden;
                    }
                }
            }
            Err(_e) => {
                // Navigation failed (no neighbor in that direction)
            }
        }
    }
}

fn update_focus_display(
    input_focus: Res<InputFocus>,
    button_query: Query<&Name, With<Button>>,
    mut display_query: Query<&mut Text, With<FocusDisplay>>,
) {
    if let Ok(mut text) = display_query.single_mut() {
        if let Some(focused_entity) = input_focus.get() {
            if let Ok(name) = button_query.get(focused_entity) {
                **text = format!("Focused: {}", name);
            } else {
                **text = "Focused: Unknown".to_string();
            }
        } else {
            **text = "Focused: None".to_string();
        }
    }
}

fn update_key_display(
    keyboard_input: Res<ButtonInput<KeyCode>>,
    gamepad_input: Query<&Gamepad>,
    mut display_query: Query<&mut Text, With<KeyDisplay>>,
) {
    if let Ok(mut text) = display_query.single_mut() {
        // Check for keyboard inputs
        for action in DirectionalNavigationAction::variants() {
            if keyboard_input.just_pressed(action.keycode()) {
                let key_name = match action {
                    DirectionalNavigationAction::Up => "Up Arrow",
                    DirectionalNavigationAction::Down => "Down Arrow",
                    DirectionalNavigationAction::Left => "Left Arrow",
                    DirectionalNavigationAction::Right => "Right Arrow",
                    DirectionalNavigationAction::Select => "Enter",
                };
                **text = format!("Last Key: {}", key_name);
                return;
            }
        }

        // Check for gamepad inputs
        for gamepad in gamepad_input.iter() {
            for action in DirectionalNavigationAction::variants() {
                if gamepad.just_pressed(action.gamepad_button()) {
                    let button_name = match action {
                        DirectionalNavigationAction::Up => "D-Pad Up",
                        DirectionalNavigationAction::Down => "D-Pad Down",
                        DirectionalNavigationAction::Left => "D-Pad Left",
                        DirectionalNavigationAction::Right => "D-Pad Right",
                        DirectionalNavigationAction::Select => "A Button",
                    };
                    **text = format!("Last Key: {}", button_name);
                    return;
                }
            }
        }
    }
}

fn highlight_focused_element(
    input_focus: Res<InputFocus>,
    input_focus_visible: Res<InputFocusVisible>,
    mut query: Query<(Entity, &mut BorderColor, &Page)>,
) {
    for (entity, mut border_color, page) in query.iter_mut() {
        if input_focus.get() == Some(entity) && input_focus_visible.0 {
            *border_color = BorderColor::all(FOCUSED_BORDER_COLORS[page.0]);
        } else {
            *border_color = BorderColor::DEFAULT;
        }
    }
}

fn interact_with_focused_button(
    action_state: Res<ActionState>,
    input_focus: Res<InputFocus>,
    mut commands: Commands,
) {
    if action_state
        .pressed_actions
        .contains(&DirectionalNavigationAction::Select)
        && let Some(focused_entity) = input_focus.get()
    {
        commands.trigger(Pointer::new(
            PointerId::Mouse,
            Location {
                target: NormalizedRenderTarget::None {
                    width: 0,
                    height: 0,
                },
                position: Vec2::ZERO,
            },
            Click {
                button: PointerButton::Primary,
                hit: HitData {
                    camera: Entity::PLACEHOLDER,
                    depth: 0.0,
                    position: None,
                    normal: None,
                    extra: None,
                },
                count: 1,
                duration: Duration::from_secs_f32(0.1),
            },
            focused_entity,
        ));
    }
}

pub fn get<Q>(&self, value: &Q) -> Option<&T>

where Q: Hash + Equivalent<T> + ?Sized,

Returns a reference to the value in the set, if any, that is equal to the given value.

Refer to get for further details.

Examples

let mut map = HashSet::new();

map.insert("foo");

assert_eq!(map.get("foo"), Some(&"foo"));

pub fn get_or_insert(&mut self, value: T) -> &T

Inserts the given value into the set if it is not present, then returns a reference to the value in the set.

Refer to get_or_insert for further details.

Examples

let mut map = HashSet::new();

assert_eq!(map.get_or_insert("foo"), &"foo");

pub fn get_or_insert_with<Q, F>(&mut self, value: &Q, f: F) -> &T

where Q: Hash + Equivalent<T> + ?Sized, F: FnOnce(&Q) -> T,

Inserts a value computed from f into the set if the given value is not present, then returns a reference to the value in the set.

Refer to get_or_insert_with for further details.

Examples

let mut map = HashSet::new();

assert_eq!(map.get_or_insert_with(&"foo", |_| "foo"), &"foo");

pub fn entry(&mut self, value: T) -> Entry<'_, T, S>

Gets the given value’s corresponding entry in the set for in-place manipulation.

Refer to entry for further details.

Examples

let mut map = HashSet::new();

let value = map.entry("foo").or_insert();

pub fn is_disjoint(&self, other: &HashSet<T, S>) -> bool

Returns true if self has no elements in common with other. This is equivalent to checking for an empty intersection.

Refer to is_disjoint for further details.

pub fn is_subset(&self, other: &HashSet<T, S>) -> bool

Returns true if the set is a subset of another, i.e., other contains at least all the values in self.

Refer to is_subset for further details.

pub fn is_superset(&self, other: &HashSet<T, S>) -> bool

Returns true if the set is a superset of another, i.e., self contains at least all the values in other.

Refer to is_superset for further details.

pub fn insert(&mut self, value: T) -> bool

Adds a value to the set.

Refer to insert for further details.

Examples

let mut map = HashSet::new();

map.insert("foo");

assert!(map.contains("foo"));

Examples found in repository

examples/gltf/gltf_extension_animation_graph.rs (line 252)

    fn on_gltf_node(
        &mut self,
        _load_context: &mut LoadContext<'_>,
        gltf_node: &gltf::Node,
        entity: &mut EntityWorldMut,
    ) {
        if self.animation_root_indices.contains(&gltf_node.index()) {
            self.animation_root_entities.insert(entity.id());
        }
    }

examples/ecs/observers.rs (line 148)

fn on_add_mine(add: On<Add, Mine>, query: Query<&Mine>, mut index: ResMut<SpatialIndex>) {
    let mine = query.get(add.entity).unwrap();
    let tile = (
        (mine.pos.x / CELL_SIZE).floor() as i32,
        (mine.pos.y / CELL_SIZE).floor() as i32,
    );
    index.map.entry(tile).or_default().insert(add.entity);
}

examples/shader_advanced/manual_material.rs (line 316)

fn extract_image_materials_needing_specialization(
    entities_needing_specialization: Extract<Res<EntitiesNeedingSpecialization<ImageMaterial>>>,
    mut dirty_specializations: ResMut<DirtySpecializations>,
) {
    // Drain the list of entities needing specialization from the main world
    // into the render-world `DirtySpecializations` table.
    for entity in entities_needing_specialization.changed.iter() {
        dirty_specializations
            .changed_renderables
            .insert(MainEntity::from(*entity));
    }
}

/// A system that adds entities that were judged to need their specializations
/// removed to the appropriate table in [`DirtySpecializations`].
fn extract_image_materials_that_need_specializations_removed(
    entities_needing_specialization: Extract<Res<EntitiesNeedingSpecialization<ImageMaterial>>>,
    mut dirty_specializations: ResMut<DirtySpecializations>,
) {
    for entity in entities_needing_specialization.removed.iter() {
        dirty_specializations
            .removed_renderables
            .insert(MainEntity::from(*entity));
    }
}

examples/ui/navigation/directional_navigation.rs (line 319)

fn process_inputs(
    mut action_state: ResMut<ActionState>,
    keyboard_input: Res<ButtonInput<KeyCode>>,
    gamepad_input: Query<&Gamepad>,
) {
    action_state.pressed_actions.clear();

    for action in DirectionalNavigationAction::variants() {
        if keyboard_input.just_pressed(action.keycode()) {
            action_state.pressed_actions.insert(action);
        }
    }

    for gamepad in gamepad_input.iter() {
        for action in DirectionalNavigationAction::variants() {
            if gamepad.just_pressed(action.gamepad_button()) {
                action_state.pressed_actions.insert(action);
            }
        }
    }
}

examples/ui/navigation/directional_navigation_overrides.rs (line 691)

fn process_inputs(
    mut action_state: ResMut<ActionState>,
    keyboard_input: Res<ButtonInput<KeyCode>>,
    gamepad_input: Query<&Gamepad>,
) {
    action_state.pressed_actions.clear();

    for action in DirectionalNavigationAction::variants() {
        if keyboard_input.just_pressed(action.keycode()) {
            action_state.pressed_actions.insert(action);
        }
    }

    for gamepad in gamepad_input.iter() {
        for action in DirectionalNavigationAction::variants() {
            if gamepad.just_pressed(action.gamepad_button()) {
                action_state.pressed_actions.insert(action);
            }
        }
    }
}

examples/shader_advanced/custom_render_phase.rs (line 514)

fn extract_camera_phases(
    mut stencil_phases: ResMut<ViewSortedRenderPhases<Stencil3d>>,
    cameras: Extract<Query<(Entity, &Camera), With<Camera3d>>>,
    mut live_entities: Local<HashSet<RetainedViewEntity>>,
) {
    live_entities.clear();
    for (main_entity, camera) in &cameras {
        if !camera.is_active {
            continue;
        }
        // This is the main camera, so we use the first subview index (0)
        let retained_view_entity = RetainedViewEntity::new(main_entity.into(), None, 0);

        stencil_phases.prepare_for_new_frame(retained_view_entity);
        live_entities.insert(retained_view_entity);
    }

    // Clear out all dead views.
    stencil_phases.retain(|camera_entity, _| live_entities.contains(camera_entity));
}

/// A resource that stores meshes that couldn't be specialized yet because their
/// materials hadn't loaded.
///
/// See the documentation for [`PendingQueues`] for more information.
#[derive(Default, Deref, DerefMut, Resource)]
struct PendingCustomMeshQueues(pub PendingQueues);

// This is a very important step when writing a custom phase.
//
// This system determines which meshes will be added to the phase.
fn queue_custom_meshes(
    custom_draw_functions: Res<DrawFunctions<Stencil3d>>,
    mut pipelines: ResMut<SpecializedMeshPipelines<StencilPipeline>>,
    pipeline_cache: Res<PipelineCache>,
    custom_draw_pipeline: Res<StencilPipeline>,
    render_meshes: Res<RenderAssets<RenderMesh>>,
    render_mesh_instances: Res<RenderMeshInstances>,
    maybe_batched_instance_buffers: Option<
        Res<BatchedInstanceBuffers<MeshUniform, MeshInputUniform>>,
    >,
    mut custom_render_phases: ResMut<ViewSortedRenderPhases<Stencil3d>>,
    mut views: Query<(&ExtractedView, &RenderVisibleEntities)>,
    view_key_cache: Res<ViewKeyCache>,
    dirty_specializations: Res<DirtySpecializations>,
    mut pending_custom_mesh_queues: ResMut<PendingCustomMeshQueues>,
    has_marker: Query<(), With<DrawStencil>>,
) {
    for (view, visible_entities) in &mut views {
        let Some(custom_phase) = custom_render_phases.get_mut(&view.retained_view_entity) else {
            continue;
        };
        let draw_custom = custom_draw_functions.read().id::<DrawMesh3dStencil>();

        let Some(&view_key) = view_key_cache.get(&view.retained_view_entity) else {
            continue;
        };

        // Since our phase can work on any 3d mesh we can reuse the default mesh 3d filter
        let Some(render_visible_mesh_entities) = visible_entities.get::<Mesh3d>() else {
            continue;
        };

        let view_pending_custom_mesh_queues =
            pending_custom_mesh_queues.prepare_for_new_frame(view.retained_view_entity);

        // First, remove meshes that need to be respecialized, and those that were removed, from the bins.
        for &main_entity in dirty_specializations
            .iter_to_dequeue(view.retained_view_entity, render_visible_mesh_entities)
        {
            custom_phase.remove(Entity::PLACEHOLDER, main_entity);
        }

        for (render_entity, visible_entity) in dirty_specializations.iter_to_queue(
            view.retained_view_entity,
            render_visible_mesh_entities,
            &view_pending_custom_mesh_queues.prev_frame,
        ) {
            // We only want meshes with the marker component to be queued to our phase.
            if has_marker.get(*render_entity).is_err() {
                continue;
            }
            let Some(mesh_instance) = render_mesh_instances.render_mesh_queue_data(*visible_entity)
            else {
                // We couldn't fetch the mesh, probably because it hasn't been
                // loaded yet. Add the entity to the list of pending custom mesh
                // queues and bail.
                view_pending_custom_mesh_queues
                    .current_frame
                    .insert((*render_entity, *visible_entity));
                continue;
            };
            let Some(mesh) = render_meshes.get(mesh_instance.mesh_asset_id()) else {
                continue;
            };

            // Specialize the key for the current mesh entity
            // For this example we only specialize based on the mesh topology
            // but you could have more complex keys and that's where you'd need to create those keys
            let mut mesh_key = view_key;
            mesh_key |= MeshPipelineKey::from_primitive_topology_and_strip_index(
                mesh.primitive_topology(),
                mesh.index_format(),
            );

            let pipeline_id = pipelines.specialize(
                &pipeline_cache,
                &custom_draw_pipeline,
                mesh_key,
                &mesh.layout,
            );
            let pipeline_id = match pipeline_id {
                Ok(id) => id,
                Err(err) => {
                    error!("{}", err);
                    continue;
                }
            };
            // At this point we have all the data we need to create a phase item and add it to our
            // phase
            custom_phase.add_retained(Stencil3d {
                sorting_info: TransparentSortingInfo3d::Sorted {
                    mesh_center: pbr::get_mesh_instance_world_from_local(
                        *visible_entity,
                        mesh_instance.current_uniform_index,
                        &render_mesh_instances,
                        maybe_batched_instance_buffers.as_deref(),
                    )
                    .transform_point3(
                        render_meshes
                            .get(mesh_instance.mesh_asset_id())
                            .unwrap()
                            .aabb_center,
                    ),
                    depth_bias: 0.0,
                },
                distance: FloatOrd(0.0),
                entity: (Entity::PLACEHOLDER, *visible_entity),
                pipeline: pipeline_id,
                draw_function: draw_custom,
                // Sorted phase items aren't batched
                batch_range: 0..1,
                extra_index: PhaseItemExtraIndex::None,
                indexed: mesh.indexed(),
            });
        }
    }
}

Additional examples can be found in:

• examples/testbed/helpers.rs
• examples/shader_advanced/compute_mesh.rs
• examples/ecs/relationships.rs
• examples/shader_advanced/specialized_mesh_pipeline.rs

pub fn replace(&mut self, value: T) -> Option<T>

Adds a value to the set, replacing the existing value, if any, that is equal to the given one. Returns the replaced value.

Refer to replace for further details.

Examples

let mut map = HashSet::new();

map.insert("foo");

assert_eq!(map.replace("foo"), Some("foo"));

pub fn remove<Q>(&mut self, value: &Q) -> bool

where Q: Hash + Equivalent<T> + ?Sized,

Removes a value from the set. Returns whether the value was present in the set.

Refer to remove for further details.

Examples

let mut map = HashSet::new();

map.insert("foo");

assert!(map.remove("foo"));

assert!(map.is_empty());

Examples found in repository

examples/ecs/observers.rs (line 159)

fn on_remove_mine(remove: On<Remove, Mine>, query: Query<&Mine>, mut index: ResMut<SpatialIndex>) {
    let mine = query.get(remove.entity).unwrap();
    let tile = (
        (mine.pos.x / CELL_SIZE).floor() as i32,
        (mine.pos.y / CELL_SIZE).floor() as i32,
    );
    index.map.entry(tile).and_modify(|set| {
        set.remove(&remove.entity);
    });
}

pub fn take<Q>(&mut self, value: &Q) -> Option<T>

where Q: Hash + Equivalent<T> + ?Sized,

Removes and returns the value in the set, if any, that is equal to the given one.

Refer to take for further details.

Examples

let mut map = HashSet::new();

map.insert("foo");

assert_eq!(map.take("foo"), Some("foo"));

assert!(map.is_empty());

pub fn allocation_size(&self) -> usize

Returns the total amount of memory allocated internally by the hash set, in bytes.

Refer to allocation_size for further details.

Examples

let mut map = HashSet::new();

assert_eq!(map.allocation_size(), 0);

map.insert("foo");

assert!(map.allocation_size() >= size_of::<&'static str>());

pub unsafe fn insert_unique_unchecked(&mut self, value: T) -> &T

Insert a value the set without checking if the value already exists in the set.

Refer to insert_unique_unchecked for further details.

Safety

This operation is safe if a value does not exist in the set.

However, if a value exists in the set already, the behavior is unspecified: this operation may panic, loop forever, or any following operation with the set may panic, loop forever or return arbitrary result.

That said, this operation (and following operations) are guaranteed to not violate memory safety.

However this operation is still unsafe because the resulting HashSet may be passed to unsafe code which does expect the set to behave correctly, and would cause unsoundness as a result.

Methods from Deref<Target = HashSet<T, S>>

pub fn capacity(&self) -> usize

Returns the number of elements the set can hold without reallocating.

Examples

use hashbrown::HashSet;
let set: HashSet<i32> = HashSet::with_capacity(100);
assert!(set.capacity() >= 100);

pub fn iter(&self) -> Iter<'_, T>

An iterator visiting all elements in arbitrary order. The iterator element type is &'a T.

Examples

use hashbrown::HashSet;
let mut set = HashSet::new();
set.insert("a");
set.insert("b");

// Will print in an arbitrary order.
for x in set.iter() {
    println!("{}", x);
}

pub fn len(&self) -> usize

Returns the number of elements in the set.

Examples

use hashbrown::HashSet;

let mut v = HashSet::new();
assert_eq!(v.len(), 0);
v.insert(1);
assert_eq!(v.len(), 1);

pub fn is_empty(&self) -> bool

Returns true if the set contains no elements.

Examples

use hashbrown::HashSet;

let mut v = HashSet::new();
assert!(v.is_empty());
v.insert(1);
assert!(!v.is_empty());

pub fn drain(&mut self) -> Drain<'_, T, A>

Clears the set, returning all elements in an iterator.

Examples

use hashbrown::HashSet;

let mut set: HashSet<_> = [1, 2, 3].into_iter().collect();
assert!(!set.is_empty());

// print 1, 2, 3 in an arbitrary order
for i in set.drain() {
    println!("{}", i);
}

assert!(set.is_empty());

pub fn retain<F>(&mut self, f: F)

where F: FnMut(&T) -> bool,

Retains only the elements specified by the predicate.

In other words, remove all elements e such that f(&e) returns false.

Examples

use hashbrown::HashSet;

let xs = [1,2,3,4,5,6];
let mut set: HashSet<i32> = xs.into_iter().collect();
set.retain(|&k| k % 2 == 0);
assert_eq!(set.len(), 3);

pub fn extract_if<F>(&mut self, f: F) -> ExtractIf<'_, T, F, A>

where F: FnMut(&T) -> bool,

Drains elements which are true under the given predicate, and returns an iterator over the removed items.

In other words, move all elements e such that f(&e) returns true out into another iterator.

If the returned ExtractIf is not exhausted, e.g. because it is dropped without iterating or the iteration short-circuits, then the remaining elements will be retained. Use retain() with a negated predicate if you do not need the returned iterator.

Examples

use hashbrown::HashSet;

let mut set: HashSet<i32> = (0..8).collect();
let drained: HashSet<i32> = set.extract_if(|v| v % 2 == 0).collect();

let mut evens = drained.into_iter().collect::<Vec<_>>();
let mut odds = set.into_iter().collect::<Vec<_>>();
evens.sort();
odds.sort();

assert_eq!(evens, vec![0, 2, 4, 6]);
assert_eq!(odds, vec![1, 3, 5, 7]);

pub fn clear(&mut self)

Clears the set, removing all values.

Examples

use hashbrown::HashSet;

let mut v = HashSet::new();
v.insert(1);
v.clear();
assert!(v.is_empty());

pub fn allocator(&self) -> &A

Returns a reference to the underlying allocator.

pub fn hasher(&self) -> &S

Returns a reference to the set’s BuildHasher.

Examples

use hashbrown::HashSet;
use hashbrown::DefaultHashBuilder;

let hasher = DefaultHashBuilder::default();
let set: HashSet<i32> = HashSet::with_hasher(hasher);
let hasher: &DefaultHashBuilder = set.hasher();

pub fn reserve(&mut self, additional: usize)

Reserves capacity for at least additional more elements to be inserted in the HashSet. The collection may reserve more space to avoid frequent reallocations.

Panics

Panics if the new capacity exceeds isize::MAX bytes and abort the program in case of allocation error. Use try_reserve instead if you want to handle memory allocation failure.

Examples

use hashbrown::HashSet;
let mut set: HashSet<i32> = HashSet::new();
set.reserve(10);
assert!(set.capacity() >= 10);

pub fn try_reserve(&mut self, additional: usize) -> Result<(), TryReserveError>

Tries to reserve capacity for at least additional more elements to be inserted in the given HashSet<K,V>. The collection may reserve more space to avoid frequent reallocations.

Errors

If the capacity overflows, or the allocator reports a failure, then an error is returned.

Examples

use hashbrown::HashSet;
let mut set: HashSet<i32> = HashSet::new();
set.try_reserve(10).expect("why is the test harness OOMing on 10 bytes?");

pub fn shrink_to_fit(&mut self)

Shrinks the capacity of the set as much as possible. It will drop down as much as possible while maintaining the internal rules and possibly leaving some space in accordance with the resize policy.

Examples

use hashbrown::HashSet;

let mut set = HashSet::with_capacity(100);
set.insert(1);
set.insert(2);
assert!(set.capacity() >= 100);
set.shrink_to_fit();
assert!(set.capacity() >= 2);

pub fn shrink_to(&mut self, min_capacity: usize)

Shrinks the capacity of the set with a lower limit. It will drop down no lower than the supplied limit while maintaining the internal rules and possibly leaving some space in accordance with the resize policy.

Panics if the current capacity is smaller than the supplied minimum capacity.

Examples

use hashbrown::HashSet;

let mut set = HashSet::with_capacity(100);
set.insert(1);
set.insert(2);
assert!(set.capacity() >= 100);
set.shrink_to(10);
assert!(set.capacity() >= 10);
set.shrink_to(0);
assert!(set.capacity() >= 2);

pub fn difference<'a>( &'a self, other: &'a HashSet<T, S, A>, ) -> Difference<'a, T, S, A>

Visits the values representing the difference, i.e., the values that are in self but not in other.

Examples

use hashbrown::HashSet;
let a: HashSet<_> = [1, 2, 3].into_iter().collect();
let b: HashSet<_> = [4, 2, 3, 4].into_iter().collect();

// Can be seen as `a - b`.
for x in a.difference(&b) {
    println!("{}", x); // Print 1
}

let diff: HashSet<_> = a.difference(&b).collect();
assert_eq!(diff, [1].iter().collect());

// Note that difference is not symmetric,
// and `b - a` means something else:
let diff: HashSet<_> = b.difference(&a).collect();
assert_eq!(diff, [4].iter().collect());

pub fn symmetric_difference<'a>( &'a self, other: &'a HashSet<T, S, A>, ) -> SymmetricDifference<'a, T, S, A>

Visits the values representing the symmetric difference, i.e., the values that are in self or in other but not in both.

Examples

use hashbrown::HashSet;
let a: HashSet<_> = [1, 2, 3].into_iter().collect();
let b: HashSet<_> = [4, 2, 3, 4].into_iter().collect();

// Print 1, 4 in arbitrary order.
for x in a.symmetric_difference(&b) {
    println!("{}", x);
}

let diff1: HashSet<_> = a.symmetric_difference(&b).collect();
let diff2: HashSet<_> = b.symmetric_difference(&a).collect();

assert_eq!(diff1, diff2);
assert_eq!(diff1, [1, 4].iter().collect());

pub fn intersection<'a>( &'a self, other: &'a HashSet<T, S, A>, ) -> Intersection<'a, T, S, A>

Visits the values representing the intersection, i.e., the values that are both in self and other.

Examples

use hashbrown::HashSet;
let a: HashSet<_> = [1, 2, 3].into_iter().collect();
let b: HashSet<_> = [4, 2, 3, 4].into_iter().collect();

// Print 2, 3 in arbitrary order.
for x in a.intersection(&b) {
    println!("{}", x);
}

let intersection: HashSet<_> = a.intersection(&b).collect();
assert_eq!(intersection, [2, 3].iter().collect());

pub fn union<'a>(&'a self, other: &'a HashSet<T, S, A>) -> Union<'a, T, S, A>

Visits the values representing the union, i.e., all the values in self or other, without duplicates.

Examples

use hashbrown::HashSet;
let a: HashSet<_> = [1, 2, 3].into_iter().collect();
let b: HashSet<_> = [4, 2, 3, 4].into_iter().collect();

// Print 1, 2, 3, 4 in arbitrary order.
for x in a.union(&b) {
    println!("{}", x);
}

let union: HashSet<_> = a.union(&b).collect();
assert_eq!(union, [1, 2, 3, 4].iter().collect());

pub fn contains<Q>(&self, value: &Q) -> bool

where Q: Hash + Equivalent<T> + ?Sized,

Returns true if the set contains a value.

The value may be any borrowed form of the set’s value type, but Hash and Eq on the borrowed form must match those for the value type.

Examples

use hashbrown::HashSet;

let set: HashSet<_> = [1, 2, 3].into_iter().collect();
assert_eq!(set.contains(&1), true);
assert_eq!(set.contains(&4), false);

pub fn get<Q>(&self, value: &Q) -> Option<&T>

where Q: Hash + Equivalent<T> + ?Sized,

Returns a reference to the value in the set, if any, that is equal to the given value.

The value may be any borrowed form of the set’s value type, but Hash and Eq on the borrowed form must match those for the value type.

Examples

use hashbrown::HashSet;

let set: HashSet<_> = [1, 2, 3].into_iter().collect();
assert_eq!(set.get(&2), Some(&2));
assert_eq!(set.get(&4), None);

pub fn get_or_insert(&mut self, value: T) -> &T

Inserts the given value into the set if it is not present, then returns a reference to the value in the set.

Examples

use hashbrown::HashSet;

let mut set: HashSet<_> = [1, 2, 3].into_iter().collect();
assert_eq!(set.len(), 3);
assert_eq!(set.get_or_insert(2), &2);
assert_eq!(set.get_or_insert(100), &100);
assert_eq!(set.len(), 4); // 100 was inserted

pub fn get_or_insert_with<Q, F>(&mut self, value: &Q, f: F) -> &T

where Q: Hash + Equivalent<T> + ?Sized, F: FnOnce(&Q) -> T,

Inserts a value computed from f into the set if the given value is not present, then returns a reference to the value in the set.

Examples

use hashbrown::HashSet;

let mut set: HashSet<String> = ["cat", "dog", "horse"]
    .iter().map(|&pet| pet.to_owned()).collect();

assert_eq!(set.len(), 3);
for &pet in &["cat", "dog", "fish"] {
    let value = set.get_or_insert_with(pet, str::to_owned);
    assert_eq!(value, pet);
}
assert_eq!(set.len(), 4); // a new "fish" was inserted

The following example will panic because the new value doesn’t match.

let mut set = hashbrown::HashSet::new();
set.get_or_insert_with("rust", |_| String::new());

pub fn entry(&mut self, value: T) -> Entry<'_, T, S, A>

Gets the given value’s corresponding entry in the set for in-place manipulation.

Examples

use hashbrown::HashSet;
use hashbrown::hash_set::Entry::*;

let mut singles = HashSet::new();
let mut dupes = HashSet::new();

for ch in "a short treatise on fungi".chars() {
    if let Vacant(dupe_entry) = dupes.entry(ch) {
        // We haven't already seen a duplicate, so
        // check if we've at least seen it once.
        match singles.entry(ch) {
            Vacant(single_entry) => {
                // We found a new character for the first time.
                single_entry.insert();
            }
            Occupied(single_entry) => {
                // We've already seen this once, "move" it to dupes.
                single_entry.remove();
                dupe_entry.insert();
            }
        }
    }
}

assert!(!singles.contains(&'t') && dupes.contains(&'t'));
assert!(singles.contains(&'u') && !dupes.contains(&'u'));
assert!(!singles.contains(&'v') && !dupes.contains(&'v'));

pub fn is_disjoint(&self, other: &HashSet<T, S, A>) -> bool

Returns true if self has no elements in common with other. This is equivalent to checking for an empty intersection.

Examples

use hashbrown::HashSet;

let a: HashSet<_> = [1, 2, 3].into_iter().collect();
let mut b = HashSet::new();

assert_eq!(a.is_disjoint(&b), true);
b.insert(4);
assert_eq!(a.is_disjoint(&b), true);
b.insert(1);
assert_eq!(a.is_disjoint(&b), false);

pub fn is_subset(&self, other: &HashSet<T, S, A>) -> bool

Returns true if the set is a subset of another, i.e., other contains at least all the values in self.

Examples

use hashbrown::HashSet;

let sup: HashSet<_> = [1, 2, 3].into_iter().collect();
let mut set = HashSet::new();

assert_eq!(set.is_subset(&sup), true);
set.insert(2);
assert_eq!(set.is_subset(&sup), true);
set.insert(4);
assert_eq!(set.is_subset(&sup), false);

pub fn is_superset(&self, other: &HashSet<T, S, A>) -> bool

Returns true if the set is a superset of another, i.e., self contains at least all the values in other.

Examples

use hashbrown::HashSet;

let sub: HashSet<_> = [1, 2].into_iter().collect();
let mut set = HashSet::new();

assert_eq!(set.is_superset(&sub), false);

set.insert(0);
set.insert(1);
assert_eq!(set.is_superset(&sub), false);

set.insert(2);
assert_eq!(set.is_superset(&sub), true);

pub fn insert(&mut self, value: T) -> bool

Adds a value to the set.

If the set did not have this value present, true is returned.

If the set did have this value present, false is returned.

Examples

use hashbrown::HashSet;

let mut set = HashSet::new();

assert_eq!(set.insert(2), true);
assert_eq!(set.insert(2), false);
assert_eq!(set.len(), 1);

pub unsafe fn insert_unique_unchecked(&mut self, value: T) -> &T

Insert a value the set without checking if the value already exists in the set.

This operation is faster than regular insert, because it does not perform lookup before insertion.

This operation is useful during initial population of the set. For example, when constructing a set from another set, we know that values are unique.

Safety

This operation is safe if a value does not exist in the set.

However, if a value exists in the set already, the behavior is unspecified: this operation may panic, loop forever, or any following operation with the set may panic, loop forever or return arbitrary result.

That said, this operation (and following operations) are guaranteed to not violate memory safety.

However this operation is still unsafe because the resulting HashSet may be passed to unsafe code which does expect the set to behave correctly, and would cause unsoundness as a result.

pub fn replace(&mut self, value: T) -> Option<T>

Adds a value to the set, replacing the existing value, if any, that is equal to the given one. Returns the replaced value.

Examples

use hashbrown::HashSet;

let mut set = HashSet::new();
set.insert(Vec::<i32>::new());

assert_eq!(set.get(&[][..]).unwrap().capacity(), 0);
set.replace(Vec::with_capacity(10));
assert_eq!(set.get(&[][..]).unwrap().capacity(), 10);

pub fn remove<Q>(&mut self, value: &Q) -> bool

where Q: Hash + Equivalent<T> + ?Sized,

Removes a value from the set. Returns whether the value was present in the set.

The value may be any borrowed form of the set’s value type, but Hash and Eq on the borrowed form must match those for the value type.

Examples

use hashbrown::HashSet;

let mut set = HashSet::new();

set.insert(2);
assert_eq!(set.remove(&2), true);
assert_eq!(set.remove(&2), false);

pub fn take<Q>(&mut self, value: &Q) -> Option<T>

where Q: Hash + Equivalent<T> + ?Sized,

Removes and returns the value in the set, if any, that is equal to the given one.

The value may be any borrowed form of the set’s value type, but Hash and Eq on the borrowed form must match those for the value type.

Examples

use hashbrown::HashSet;

let mut set: HashSet<_> = [1, 2, 3].into_iter().collect();
assert_eq!(set.take(&2), Some(2));
assert_eq!(set.take(&2), None);

pub fn allocation_size(&self) -> usize

Returns the total amount of memory allocated internally by the hash set, in bytes.

The returned number is informational only. It is intended to be primarily used for memory profiling.

Trait Implementations

impl Component for MeshesToReextractNextFrame

where MeshesToReextractNextFrame: Send + Sync + 'static,

const STORAGE_TYPE: StorageType = bevy_ecs::component::StorageType::SparseSet

A constant indicating the storage type used for this component.

type Mutability = Mutable

A marker type to assist Bevy with determining if this component is mutable, or immutable. Mutable components will have Component<Mutability = Mutable>, while immutable components will instead have Component<Mutability = Immutable>.

fn register_required_components( _requiree: ComponentId, required_components: &mut RequiredComponentsRegistrator<'_, '_>, )

Registers required components.

fn clone_behavior() -> ComponentCloneBehavior

Called when registering this component, allowing to override clone function (or disable cloning altogether) for this component.

fn relationship_accessor() -> Option<ComponentRelationshipAccessor<MeshesToReextractNextFrame>>

Returns ComponentRelationshipAccessor required for working with relationships in dynamic contexts.

fn on_add() -> Option<for<'w> fn(DeferredWorld<'w>, HookContext)>

Gets the on_add ComponentHook for this Component if one is defined.

fn on_insert() -> Option<for<'w> fn(DeferredWorld<'w>, HookContext)>

Gets the on_insert ComponentHook for this Component if one is defined.

fn on_discard() -> Option<for<'w> fn(DeferredWorld<'w>, HookContext)>

Gets the on_discard ComponentHook for this Component if one is defined.

fn on_remove() -> Option<for<'w> fn(DeferredWorld<'w>, HookContext)>

Gets the on_remove ComponentHook for this Component if one is defined.

fn on_despawn() -> Option<for<'w> fn(DeferredWorld<'w>, HookContext)>

Gets the on_despawn ComponentHook for this Component if one is defined.

fn map_entities<E>(_this: &mut Self, _mapper: &mut E)

where E: EntityMapper,

Maps the entities on this component using the given EntityMapper. This is used to remap entities in contexts like scenes and entity cloning. When deriving Component, this is populated by annotating fields containing entities with #[entities]

impl Default for MeshesToReextractNextFrame

fn default() -> MeshesToReextractNextFrame

Returns the “default value” for a type.

impl Deref for MeshesToReextractNextFrame

type Target = HashSet<MainEntity, EntityHash>

The resulting type after dereferencing.

fn deref(&self) -> &<MeshesToReextractNextFrame as Deref>::Target

Dereferences the value.

impl DerefMut for MeshesToReextractNextFrame

fn deref_mut(&mut self) -> &mut <MeshesToReextractNextFrame as Deref>::Target

Mutably dereferences the value.

impl Resource for MeshesToReextractNextFrame

where MeshesToReextractNextFrame: Send + Sync + 'static,