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[rbdr/lissajous] / lib / factories / global.js

import { Entity } from '@serpentity/serpentity';
import Position from '@serpentity/components.position';
import EulerAngle from '@serpentity/components.euler_angle';
import Velocity from '@serpentity/components.velocity';
import Radius from '../components/radius';
import Up from '../components/up';
import Configuration from '../components/configuration';

/**
  * This file is a factory for global objects. It doesn't enforce it, but
  * there should be only one of these entities in the engine at a given
  * time.
  */

/**
  * Creates a data entity that holds the configuration.
  */
export function configuration() {

  const entity = new Entity();
  entity.addComponent(new Configuration());

  return entity;
}

/**
  * Creates a camera, used to modify the 3D view.
  */
export function camera() {

  const entity = new Entity();
  entity.addComponent(new Position());
  entity.addComponent(new EulerAngle());
  entity.addComponent(new Velocity({
    x: 0,
    y: Math.PI / 30,
    z: 0,
  }));
  entity.addComponent(new Radius({
    radius: 5
  }));
  entity.addComponent(new Up());

  return entity;
}