Struct DirectionalNavigation

pub struct DirectionalNavigation<'w> {
    pub focus: ResMut<'w, InputFocus>,
    pub map: Res<'w, DirectionalNavigationMap>,
}

A system parameter for navigating between focusable entities in a directional way.

Fields

focus: ResMut<'w, InputFocus>

The currently focused entity.

map: Res<'w, DirectionalNavigationMap>

The navigation map containing the connections between entities.

Implementations

impl DirectionalNavigation<'_>

pub fn navigate( &mut self, direction: CompassOctant, ) -> Result<Entity, DirectionalNavigationError>

Navigates to the neighbor in a given direction from the current focus, if any.

Returns the new focus if successful. Returns an error if there is no focus set or if there is no neighbor in the requested direction.

If the result was Ok, the InputFocus resource is updated to the new focus as part of this method call.

Trait Implementations

impl<'w> Debug for DirectionalNavigation<'w>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl SystemParam for DirectionalNavigation<'_>

type State = FetchState

Used to store data which persists across invocations of a system.

type Item<'w, 's> = DirectionalNavigation<'w>

The item type returned when constructing this system param. The value of this associated type should be Self, instantiated with new lifetimes.

fn init_state(world: &mut World, system_meta: &mut SystemMeta) -> Self::State

Registers any World access used by this SystemParam and creates a new instance of this param’s State.

unsafe fn new_archetype( state: &mut Self::State, archetype: &Archetype, system_meta: &mut SystemMeta, )

For the specified Archetype, registers the components accessed by this SystemParam (if applicable).a

fn apply(state: &mut Self::State, system_meta: &SystemMeta, world: &mut World)

Applies any deferred mutations stored in this SystemParam’s state. This is used to apply Commands during ApplyDeferred.

fn queue( state: &mut Self::State, system_meta: &SystemMeta, world: DeferredWorld<'_>, )

Queues any deferred mutations to be applied at the next ApplyDeferred.

unsafe fn validate_param<'w, 's>( state: &'s Self::State, _system_meta: &SystemMeta, _world: UnsafeWorldCell<'w>, ) -> Result<(), SystemParamValidationError>

Validates that the param can be acquired by the get_param.

unsafe fn get_param<'w, 's>( state: &'s mut Self::State, system_meta: &SystemMeta, world: UnsafeWorldCell<'w>, change_tick: Tick, ) -> Self::Item<'w, 's>

Creates a parameter to be passed into a SystemParamFunction.

impl<'w, 's> ReadOnlySystemParam for DirectionalNavigation<'w>

where ResMut<'w, InputFocus>: ReadOnlySystemParam, Res<'w, DirectionalNavigationMap>: ReadOnlySystemParam,