Struct MassPropertyHelper

pub struct MassPropertyHelper<'w, 's> { /* private fields */ }

A SystemParam that provides helper methods for computing and updating mass properties.

Implementations

impl MassPropertyHelper<'_, '_>

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

Updates the ComputedMass, ComputedAngularInertia, and ComputedCenterOfMass of the given entity.

This takes into account the mass properties of descendants, unless the given entity has the NoAutoMass, NoAutoAngularInertia, or NoAutoCenterOfMass marker components.

pub fn total_mass_properties(&self, entity: Entity) -> MassProperties

Computes the total mass properties of the given entity, taking into account the mass properties of descendants.

This ignores the NoAutoMass, NoAutoAngularInertia, and NoAutoCenterOfMass marker components.

pub fn descendants_mass_properties(&self, entity: Entity) -> MassProperties

Computes the total mass properties of the descendants of the given entity.

This ignores the NoAutoMass, NoAutoAngularInertia, and NoAutoCenterOfMass marker components.

pub fn local_mass_properties(&self, entity: Entity) -> Option<MassProperties>

Computes the local mass properties of the given entity.

This only considers the entity’s own Mass, AngularInertia, CenterOfMass, and/or ColliderMassProperties if present, not those of its children.

If the entity has no mass properties or the entity does not exist, None is returned.

Trait Implementations

impl SystemParam for MassPropertyHelper<'_, '_>

type State = FetchState

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

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

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 apply_deferred.

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

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

unsafe fn validate_param<'w, 's>( state: &'s Self::State, system_meta: &SystemMeta, world: UnsafeWorldCell<'w>, ) -> bool

Validates that the param can be acquired by the get_param. Built-in executors use this to prevent systems with invalid params from running. For nested SystemParams validation will fail if any delegated validation fails.

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 MassPropertyHelper<'w, 's>

where Query<'w, 's, (Option<Read<Mass>>, Option<Read<AngularInertia>>, Option<Read<CenterOfMass>>, Option<Read<ColliderMassProperties>>, Option<Read<ColliderTransform>>, Has<Sensor>), Or<(With<Mass>, With<AngularInertia>, With<CenterOfMass>, (With<ColliderMassProperties>, With<ColliderTransform>, Without<Sensor>))>>: ReadOnlySystemParam, Query<'w, 's, (Write<ComputedMass>, Write<ComputedAngularInertia>, Write<ComputedCenterOfMass>, Option<Read<Mass>>, Option<Read<AngularInertia>>, Option<Read<CenterOfMass>>, Has<NoAutoMass>, Has<NoAutoAngularInertia>, Has<NoAutoCenterOfMass>)>: ReadOnlySystemParam, Query<'w, 's, Read<Children>>: ReadOnlySystemParam,