flockn
======

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flockn is a lightweight declarative game engine. (While it uses [Babel](https://github.com/babel/babel) to generate ECMAScript 5 compatible output, the use of Babel or ES6 in flockn-related project is not enforced. There no ES6 features that need to be used as flockn exposes an easy-to-use ES5 interface.)

How does it work?
-----------------
```javascript
// Import flockn function from the flockn module
import flockn from 'flockn';

// Create a game instance, no need to store it as a variable
// Using the flockn module is a shorthand for: 
//    import Game from 'flockn/game'; new Game(function() { ...
flockn(function() {
  // The logic for the game itself

  // Add a scene to the game
  this.addScene(function() {
    // The logic for this scene

    // Give the scene a name
      this.name = 'myscene';

      // Create a new game object inside the scene
      this.addGameObject(function() {
        // The logic for this game object

        // Set the position for this game object
          this.position.x = 100;
          this.position.y = 100;

          // This game object now holds a label with the text "Hello World"
          this.texture.label.text = 'Hello World';
      });
  });

  // Start the game loop
  // Since only have one scene, we don't need to specify a scene name.
  // In any other case it would be: `this.run('myscene');`
  this.run();

});
```
Putting everything in one file doesn't work for anything bigger than a small experiment, so I would recommend to
to put each gameobjects, behaviors and scene in separate files. For a more real-life example, take a look at the
[template](http://github.com/freezedev/flockn-template).
There is also an online playground.

Examples
--------
To run the examples for yourself, run `npm run examples` after all dependencies have been installed (`npm install`).
Then navigate to `http://localhost:8080` to see all the examples.

Features
--------
* Taggable game objects and behaviors
* Small (less than 30kB minified)

Philosophy
----------
* Friendly to JavaScript transpilers: Babel, CoffeeScript, TypeScript and more
* Transpilers are optional though: You don't need to use a transpiler with `flockn`
* Lightweight
* Events everywhere (Having an `EventEmitter`-like interface)
* Pluggable
* Over-simplification of things. Examples:
  * A flockn game instance binds scenes on itself. In other game engines, a scene director usually handles it and is mounted to the game/application instance
  * A texture can either be an image, a text, a color or a combination of these. In other game engines, a texture only holds the data of a texture whereas other objects need a texture to display anything on the screen
* Functions are the best way to describe an object
* Split entity-component model into 
    * Game objects (base object)
    * Behaviors (logic) 
    * Models (data)

Some decisions that need to be made
-----------------------------------
- Should game objects have the attributes of behaviors?
- Should game objects have the attributes of models?
- Should `Object.observe` be used for attributes? (Reducing the `Model#get` and `Model#set` overhead)
- Is there a possibility to simplify the access of game objects from behaviors?

Alternatives
------------
* If you are just interested in the DOM/jQuery side of things and wish more control over what's getting added to the DOM, you should try [Lyria](https://github.com/freezedev/lyria).
* For a full-blown and less opiniated game engine, you could try [Phaser](https://github.com/photonstorm/phaser).

Building for yourself
---------------------
flockn uses Grunt as its task runner.
Grunt can either be installed through `npm install -g grunt-cli` or you can use it as a local dependency.
After that, navigate to the flockn root folder and type `npm install` to install all necessary dependencies.  

Type `grunt` (or `npm run grunt`) to build everything. You also need to have Bower installed to take a look at the examples.

License
-------
This is public domain (UNLICENSE). If public domain does not work for you, you can use MIT alternatively.