Timestep

A fixed timestep.

How to use

Integrator

Timestep uses an integrator to connect a game loop with game state.

Create the following interface:

// my_integrator.ts

import type { IntegratorInterface } from "timestep";

class Integrator implements IntegratorInterface {
	integrate(msInterval: number): void {
		// tick through physics step
	}

	render(deltaRemainder: number): void {
		// Draw to canvas or update dom.
		//
		// Interpolate between [previous state, current state]
		// with the delta remainder [0, 1].
	}

	error(e: Error) {
		// maximum integration time was exceeded
	}
}

The integrate function is called between renders.

After integration, the render funtion is called and given the timestep remainder.

Timestep

Pass an Integrator to an instance of Timestep.

import { Timestep } from "timestep";
import { Integrator } from "my_integrator.ts";

let intervalMs = 10; // millisecond integration interval
let integrator = new Integrator();
const timestep = new Timestep({ intervalMs, integrator });

Then call start or stop where appropriate.

timestep.start();
timestep.stop();

Example

Checkout a tiny ( code | live ) example.

License

Timestamp-js is released under the BSD 3-Clause License.