darlingjs 

Lightweight entity, component, system based game engine. With flexible architecture. Decupled from any dependecy. So all interaction with Box2D, Render system, Particle System and so on put in pluggable modules. Use fluent API Crafty.js, jQuery like.

1.0

Recipes

Create your own pipeline recipe

var darling = require('darlingjs');
var system1 = require('system1');
var system2 = require('system2');
var system3 = require('system3');

module.exports = {
  myRecipe: darling.recipe.sequence([
    system1(),
    system2(),
    system3()
  ]) 
};

Usage as common system

var darling = require('darlingjs');
var myRecipe = require('myRecipes').myRecipe;

var pipeline = darling.world()
  pipe(myRecipe());
  

Extentions

Pipe

darlingjs/darlingjs-pipe advance utils for pipeline

Repeat

Repeat sequence of system in pipeline.

//will repeat system1, system2 in pipeline of the world
darling.world('the-world')
  .pipe(repeat(3)
    .pipe(system1())
    .pipe(system2())
  );

Runners

Use for run world in a circle of pipelines

• live-on-animation-frame to update 60 times in second on Animation Frame
• live-on-promise to update once last lazy system resolves its Promise

Usage

var onFrame = require('darlingjs-live-on-animation-frame');

var w = darling.world('the-world')
  .pipe(box2d())
  .pipe(pixijs())
  .live(onFrame({
    autostart: true
  }));

//world lives now, only need to add entities to it

Support

• documentation
• forum

Examples

• Game of Pong with sources;
• In Progress Red Cabrioler with sources;
• Repo with other sources;

Quick Start

Creating the World

Create the World for Box2D experiments

var world = darlingjs.world('myGame', [
    //inject some modules

    //get 2D components
    'ngFlatland',

    //get Common Physics components
    'ngPhysics',

    //get Box2D implementation of Physics components
    'ngBox2DEmscripten'
], {
    fps: 60
});

DarlingJS is lightweight framework so it's decoupled from any rendering, physics, sound, assets and so on libraries. And it possible to develop on pure javascript with your own simulation systems.

Every darlingjs modules start with prefix 'ng', for example: 'ngPhysics'.

Add systems

add physics simulation system

world.$add('ngBox2DSystem', {
    //define gravity of box2d world
    gravity: {
        x: 0,
        y: 9.8
    },

    //define properties of physics simulation
    velocityIterations: 3,    
    positionIterations: 3
});

add view port system for definition 2D camera position

world.$add('ng2DViewPort', {
    //centor of the camera
    lookAt: {
        x: width / 2, y: height / 2
    },

    //size of the camera view
    width: width,
    height: height
});

add box2d debug draw visualization

world.$add('ngBox2DDebugDraw', {
    //target div/convas element. For div element automaticaly create canvas element and place into the div
    domID: 'gameView', 

    //size of canvas
    width: width, height: height
});

add drugging support system.

world.$add('ngBox2DDraggable', { 
    //target div/convas element
    domId: 'gameView', 

    //width, height of it
    width: width, height: height 
});

Create Entity

Create entity of draggable box and add it to the world

darlingjs.$e('box', {
//define position
    ng2D: {
        x: 0.0,
        y: 0.0
    },

//define size of
    ng2DSize: {
        width: 10.0,
        height: 10.0
    },

//mark entity as physics object
    ngPhysics: {},

//mark entity as draggable object
    ngDraggable: {}
});

Here is alternative notation: When you have a lot of components in default state, it useful to count of components by array

darlingjs.$e('box', ['ng2D', 'ng2DSize', 'ngPhysics', 'ngDraggable']}

Start The Game

To run update of game the world 60 times in second just use:

world.$start();

One frame emulation:

world.$update(1/60);

Create custom system with custom component

Create system that automaticaly increase life of any entities with 'ngLife' and 'lifeHealer' components. So you if you want to heal some entity you can just add 'lifeHealer' component to it.

Usage

//start healing entity

entity.$add('healer');

//stop healing entity

entity.$remove('healer');

Define component and system

//define healer component

world.$c('healer', { 
    power: 0.1,
    maxLife: 100.0
});

//define and add healer system to the game world
//!ATTENTION! in next verstion $node and $nodes will be changed to the $entity and $entities

world.$s('healerSystem', {

    //apply to components:
    $require: ['ngLife', 'healer'],

    //iterate each frame for each entity
    $update: ['$node', function($node) {
        if ($node.ngLife.life <= this.healer.maxLife) {
            //heals entity
            $node.ngLife.life += this.healer.power;
        } else {
            //stop healing when life reach of maxLife
            $node.$remove('healer');
        }
    }]
});

Inspired by

• AngularJs - dependecy injections;
• Ash - component, entity, system architecture;
• CraftyJS - fluent api;

Pluggable darlingjs Modules

• 2D Renderering uses pixi.js;
• Physics uses emscripted box2d 2.2.1 or box2dweb 2.1a;
• Performance (FPS/Mem) metter uses Stats.js;
• Flatland (2D components);
• Generators (systems of procedural generation of infinity world);
• Particles (systems and components for emitting particles);
• Player (components for store player state: score, life);

Comming soon Modules

• Advanced Particle System;
• AI
• FlashJS, EaselJS Rendering;
• Sound;
• and so on.

Example of Usage

Game Engine now in active developing and here is just proof of concept.

var world = darlingjs.world('myGame', ['ngModule', 'flatWorld'], {
    fps: 60
});

world.$add('ngDOMSystem', { targetId: 'gameID' });
world.$add('ngFlatControlSystem');
world.$add('ng2DCollisionSystem');

world.$e('player', [
    'ngDOM', { color: 'rgb(255,0,0)' },
    'ng2D', {x : 0, y: 50},
    'ngControl',
    'ngCollision'
]);

for (var i = 0, l = 10; i < l; i++) {
    var fixed = Math.random() > 0.5;
    world.$e('obstacle_' + i, [
        'ngDOM', { color: fixed?'rgb(0, 255, 0)':'rgb(200, 200, 0)'},
        'ng2D', {x : 10 + 80 * Math.random(), y: 10 + 80 * Math.random()},
        'ngCollision', {fixed: fixed}
    ]);
}

world.$e('goblin', [
    'ngDOM', { color: 'rgb(255,0,0)' },
    'ng2D', {x : 99, y: 50},
    'ngRamble', {frame: {
        left: 50, right: 99,
        top: 0, bottom: 99
    }},
    'ngScan', {
        radius: 3,
        target: 'ngPlayer',
        switchTo: {
            e:'ngAttack',
            params: {
                switchTo:'ngRamble'
            }
        }
    },
    'ngCollision'
]);

world.$start();

Create Module

var ngModule = darlingjs.module('ngModule');

ngModule.$c('ngCollision', {
    fixed: false
});

ngModule.$c('ngScan', {
    target: 'ngPlayer'
});

ngModule.$c('ngRamble', {
    frame: {
        left: 0, right: 0,
        top: 0, bottom: 0
    }
});

ngModule.$c('ngPlayer', {
});

ngModule.$c('ngDOM', {
    color: 'rgb(255,0,0)'
});

ngModule.$c('ng2D', {
    x: 0.0,
    y: 0.0,
    width: 10.0,
    height: 10.0
});

ngModule.$c('ngControl', {
    speed: 10,
    keys:{ UP_ARROW: -90, DOWN_ARROW: 90, RIGHT_ARROW: 0, LEFT_ARROW: 180}
});

ngModule.$system('ng2DRamble', {
    
    $require: ['ngRamble', 'ng2D'],

    _updateTarget: function($node) {
        $node._target = {
            x: 4 * Math.random() - 2,
            y: 4 * Math.random() - 2
        };

        $node._target = this._normalizePosition($node._target, $node.frame);
    },

    _normalizePosition: function(p, frame) {
        if (p.x < frame.left) {
            p.x = frame.left;
        }

        if (p.x > frame.right) {
            p.x = frame.right;
        }

        if (p.y < frame.top) {
            p.y = frame.top;
        }

        if (p.y > frame.bottom) {
            p.y = frame.bottom;
        }
    },
    
    _distanceSqr: function(p1, p2) {
        var dx = p1.x - p2.x;
        var dy = p1.y - p2.y;
        return dx * dx + dy * dy;
    },

    $update: ['$node', function($node) {
        if (!$node._target) {
            this._updateTarget($node);
        } else if (this._distanceSqr($node.ng2D, $node._target) < 1) {
            this._updateTarget($node);
        } else {
            var dx = Math.abs($node._target.x - $node.ng2D.x);
            var dy = Math.abs($node._target.y - $node.ng2D.y);
            if (dx > dy) {
                $node.ng