@woosh/meep-engine/src/engine/ecs/systems/MotionSystem.js

Pure JavaScript game engine. Fully featured and production ready.

import Motion from '../components/Motion.js';
import { System } from '../System.js';
import { Transform } from '../transform/Transform.js';


class MotionSystem extends System {
    constructor() {
        super();

        this.dependencies = [Motion];
    }

    update(timeDelta) {
        const entityManager = this.entityManager;
        const ecd = entityManager.dataset;

        if (ecd === null) {
            return;
        }

        ecd.traverseEntities([Motion, Transform], function (motion, transform) {
            const positionDelta = motion.velocity.clone().multiplyScalar(timeDelta);
            transform.position.add(positionDelta);
        });
    }
}


export default MotionSystem;