mwg API
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    Class FixedStepper

    Turns the variable frame time Scene.update(dt) receives into fixed simulation steps.

    Game clamps and scales each frame's dt but does not make it constant, so a simulation that must be deterministic and independent of the display's refresh rate (a physics solver, a lockstep game) feeds dt here and runs its tick once per returned step instead. The leftover time carries to the next frame, and maxSubsteps bounds a slow frame so catching up cannot make the next frame slower still.

    import { FixedStepper } from '@datamoc/mwg/core';

    const stepper = new FixedStepper(1 / 60);
    const world = { step: (h: number) => console.log('step', h) };
    // inside Scene.update(dt), here one 40 ms frame:
    const dt = 0.04;
    stepper.advance(dt, (h) => world.step(h));
    const blend = stepper.alpha; // 0..1 into the next step, for interpolated drawing
    Index
    constructor
    maxSubsteps step
    alpha
    advance reset
    maxSubsteps: number
    step: number
    • get alpha(): number

      how far into the next step the leftover time reaches, 0 up to (not including) 1

      Returns number

    • Adds dt seconds and runs tick(step) for every whole step now due.

      Parameters

      • dt: number
      • tick: (step: number) => void

      Returns number

      how many steps ran; time beyond maxSubsteps steps is dropped, not banked

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