tnt-ecs

tnt-ecs

Simple Entity Component System

Basic example

import Core from 'tnt-ecs';
import System from 'tnt-ecs';
import Entity from 'tnt-ecs';
import Component from 'tnt-ecs';

class Position extends Component {
  
  getName() {
    return 'position';
  }
  
  getDefaults() {
    return {x: 0, y: 0};
  }
}

class Color extends Component {
  
  getName() {
    return 'color';
  }
  
  getDefaults() {
    return {r: 255, g: 255, b: 255};
  }
}

class Rendering extends System {
  
  test(entity) {
    return entity.components.position && entity.components.color;
  }
  
  update(entity) {
    console.log( entity.components.position.x, entity.components.position.x );
    console.log( entity.components.color.r, entity.components.color.g, entity.components.color.b );
  }
  
  preUpdate() {
    console.log('Before all entities are being updated');
  }  

  postUpdate() {
    console.log('After all entities are being updated');
  }
  
  enter(entity) {
    console.log('Enter system', entity);
  }
  
  exit(entity) {
    console.log('Exit system', entity);
  }
}

const ecs = new Core();
const rendering = new Rendering();
ecs.addSystem(rendering);

// Start/stop the update loop
ecs.stop();
ecs.start();

// Start/stop the system
rendering.stop();
rendering.start();

// Add entities
ecs.addEntity(new Entity([
  new Position(),
  new Color()
]));

ecs.addEntity(new Entity([
  new Position({x: 50}),
  new Color({b: 20})
]));

ecs.addEntity(new Entity([
  new Position({x: 50}),
  new Color({r: 0, g: 0, b: 0})
]));

const camera = new Entity([
	new Position({x: 50})
]);

// Removing / adding components
camera.addComponent(new Color());
camera.removeComponent('color');
camera.removeComponents(['position', 'color']);

if (camera.hasComponent('position')) {
	console.log('This entity has the position component');
}

// Tagging
camera.tag('camera');
camera.removeTag('camera');

if (camera.hasTag('camera')) {
	console.log('This entity has the camera tag');
}