Struct Sim 

pub struct Sim {
    pub world: World,
    pub step: Duration,
    /* private fields */
}

Fixed-timestep simulation state.

Fields

world: World

Entity/component store. Game crates add their own components here.

step: Duration

Fixed step size. Defaults to 60 Hz.

Implementations

impl Sim

pub fn new(step: Duration) -> Sim

pub fn with_default_step() -> Sim

60 Hz fixed-step sim.

pub fn add_system<M>(&mut self, system: impl IntoSystem<(), (), M>) -> &mut Sim

Register a system into the per-step schedule.

pub fn add_chained_systems<M>( &mut self, systems: impl IntoScheduleConfigs<Box<dyn System<Out = (), In = ()>>, M>, ) -> &mut Sim

Register systems with a guaranteed execution order.

A bare Schedule does not preserve add_system insertion order for systems with conflicting accesses, so multi-step pipelines (economy, combat) must register as one (a, b, c).chain() tuple through here instead of separate add_system calls.

pub fn step(&mut self, dt: Duration) -> u32

Advance the sim by dt wall time, running zero or more fixed steps. Returns the number of steps run.

pub fn tick(&mut self)

Run the schedule exactly once, advancing sim time by one step. Tick-model games (integer logic steps) drive this directly instead of the wall-clock Sim::step accumulator.