git.r.bdr.sh - rbdr/serpentity/blob - README.md

   1 # Serpentity
   2
   3 Serpentity is a simple entity framework inspired by Ash.
   4
   5 Usage:
   6
   7     let Serpentity = require('serpentity');
   8
   9 or:
  10
  11     <script src="/node_modules/serpentity/dist/serpentity.js"></script>
  12
  13 ## Instantiating an engine
  14
  15     let engine = Serpentity();
  16
  17 Add entities or systems, systems are added with a priority (the smaller
  18 the number, the earlier it will be called):
  19
  20     engine.addEntity(entityFactory());
  21     engine.addSystem(new GameSystem(), priority);
  22
  23 Update all systems:
  24
  25     engine.update(dt);
  26
  27 Remove entities or systems:
  28
  29     engine.removeEntity(entityReference);
  30     engine.removeSystem(systemReference);
  31
  32 ## Creating Entities
  33
  34 Entities are the basic object of Serpentity, and they do nothing.
  35
  36     let entity = new Serpentity.Entity();
  37
  38 All the behavior is added through components
  39
  40 ## Creating Components
  41
  42 Components define data that we can add to an entity. This data will
  43 eventually be consumed by "Systems"
  44
  45     let PositionComponent = class PositionComponent extends Serpentity.Component {
  46       constructor (config) {
  47         super(config);
  48
  49         this.x = this.x || 0;
  50         this.y = this.y || 0;
  51       }
  52     };
  53
  54 You can add components to entities by using the add method:
  55
  56     entity.addComponent(new PositionComponent());
  57
  58
  59 Systems can refer to entities by requesting nodes.
  60
  61 ## Working with Nodes
  62
  63 Nodes are sets of components that you define, so your system can require
  64 entities that always follow the API defined in the node.
  65
  66     let MovementNode = class MovementNode extends Serpentity.Node;
  67     MovementNode.position = PositionComponent;
  68     MovementNode.motion = MotionComponent;
  69
  70 You can then request an array of all the nodes representing entities
  71 that comply with that API
  72
  73     engine.getNodes(MovementNode);
  74
  75 ## Creating Systems
  76
  77 Systems are called on every update, and they use components through nodes.
  78
  79     let TestSystem = class TestSystem extends Serpentity.System {
  80       added (engine){
  81         this.nodeList = engine.getNodes(MovementNode);
  82       },
  83       removed (engine){
  84         this.nodeList = undefined;
  85       }
  86       update (dt){
  87         let node;
  88         for (node of this.nodeList) {
  89           console.log(`Current position is: ${node.position.x},${node.position.y}`);
  90         }
  91       }
  92     };
  93
  94 ## That's it
  95
  96 Just run `engine.update(dt)` in your game loop :D
  97
  98 ## TO-DO
  99
 100 * Minimize code (Uglify does not support ES6 yet)
 101 * Check Performance
 102
 103 [ash]: http://www.ashframework.org/