Struct bevy::time::FixedTimestep

pub struct FixedTimestep { /* private fields */ }

A system run criteria that enables systems or stages to run at a fixed timestep between executions.

This does not guarantee that the time elapsed between executions is exactly the provided fixed timestep, but will guarantee that the execution will run multiple times per game tick until the number of repetitions is as expected.

For example, a system with a fixed timestep run criteria of 120 times per second will run two times during a ~16.667ms frame, once during a ~8.333ms frame, and once every two frames with ~4.167ms frames. However, the same criteria may not result in exactly 8.333ms passing between each execution.

When using this run criteria, it is advised not to rely on Time::delta or any of it’s variants for game simulation, but rather use the constant time delta used to initialize the FixedTimestep instead.

For more fine tuned information about the execution status of a given fixed timestep, use the FixedTimesteps resource.

Implementations

impl FixedTimestep

pub fn step(step: f64) -> FixedTimestep

Creates a FixedTimestep that ticks once every step seconds.

pub fn steps_per_second(rate: f64) -> FixedTimestep

Creates a FixedTimestep that ticks once every rate times per second.

pub fn with_label(self, label: &str) -> FixedTimestep

Sets the label for the timestep. Setting a label allows a timestep to be observed by the global FixedTimesteps resource.

Trait Implementations

impl Default for FixedTimestep

fn default() -> FixedTimestep

Returns the “default value” for a type.

impl System for FixedTimestep

type In = ()

The system’s input. See In for FunctionSystems.

type Out = ShouldRun

The system’s output.

fn name(&self) -> Cow<'static, str>

Returns the system’s name.

fn archetype_component_access(&self) -> &Access<ArchetypeComponentId>

Returns the system’s archetype component Access.

fn component_access(&self) -> &Access<ComponentId>

Returns the system’s component Access.

fn is_send(&self) -> bool

Returns true if the system is Send.

fn is_exclusive(&self) -> bool

Returns true if the system must be run exclusively.

unsafe fn run_unsafe(&mut self, _input: (), world: &World) -> ShouldRun

Runs the system with the given input in the world. Unlike System::run, this function takes a shared reference to World and may therefore break Rust’s aliasing rules, making it unsafe to call.

fn apply_buffers(&mut self, world: &mut World)

fn initialize(&mut self, world: &mut World)

Initialize the system.

fn update_archetype_component_access(&mut self, world: &World)

Update the system’s archetype component Access.

fn check_change_tick(&mut self, change_tick: u32)

fn get_last_change_tick(&self) -> u32

Gets the system’s last change tick

fn set_last_change_tick(&mut self, last_change_tick: u32)

Sets the system’s last change tick

fn run(&mut self, input: Self::In, world: &mut World) -> Self::Out

Runs the system with the given input in the world.

fn default_labels(&self) -> Vec<SystemLabelId, Global>

The default labels for the system