entity
v0.0.0
Published
Javascript Game Engine
Downloads
320
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EntityJS
An HTML5 javascript game engine utlizing the entity-component design. Write highly flexible code in a powerful javascript framework.
EntityJS Website | Demos | Tutorials | API
Version 0.5.0
Systems and groups have been added. Groups are used to contain similar entities and can be used for searches or in systems. Systems should contain all the logic of a game, like updates, drawing and input. Components should only add attributes to an entity while systems will run everything together using groups.
See the examples folder for help.
API
Currently the API is out of date. It will slowly be updated everyday.
What makes this different from other javascript game engines?
Entity strives to be the most flexible game engine available. We understand no one likes rewritting the same functions and lines of code over and over. So we have developed a solution to this problem and that is the component-entity design. The traditional approach to game engine design is creating a hierarchy of classes. This is infact the most tightly coupled design. This creates close coupled classes whos functionality is strictly typed to one class, its not easily portable to other projects, good luck copying that one needed function and as game development progresses classes get bigger and more complex. You will eventually end up with god-classes who control most of the game logic.
This becomes a big mess.
In the world of entity-component designs. All logic is implemented in a component, as big or small as you want. You can then create an entity and add/remove components to it. The entity is a live represantation of all its components. With this low coupling of components and entities you can mix and match components together to create powerful functionality yet still portable and robust.
Requirements
You must have at least Ruby 1.8.1+.
Installion
EntityJS is now an easy to install gem. In the terminal type in:
gem install entityjs
This will install the latest version of the gem and now you can easily create some games!
Usage
When using these commands make sure you are always in the root directory of your game.
Creating a New Game
Creating a game is simple, move to any directory and type in:
entityjs new mygame
This will create a new game using the default template.
Create a game with a platform template:
entityjs new mygame platform
See all available templates:
entityjs templates
Creating a Component
entityjs comp rock
This will create a new component called rock at scripts/rock.js and will create a test file.
entityjs comp display/hero
This will create a hero component in the directory scripts/display.
Creating a Test
entityjs test name test1 test1
Create a test in /tests/name_test.js with two test methods.
Build Game
entityjs build
This will minify all entityjs src code and game src code into one file inside /builds
Running the Game / Tests
Make sure the server is running:
entityjs server
To play visit:
localhost:2345
To run tests visit:
localhost:2345/test
Assets are located here:
localhost:2345/assets/*name
View all commands
Directory Structure
Assets - Contains all external assets
- Images - Add any images here and retrieve them with
re.assets.images
- Sounds - Add any sounds and retrieve them with
re.assets.sounds
- Images - Add any images here and retrieve them with
Build - Contains built game
Scripts - Contains all js, coffee sources. Xml, tmx and json files will be converted into js.
- Plugins - Contains minified scripts for plugin play.
Tests - Contains test files to run in QUnit
Styles - Contains all css to be included. Will support sass and others later on.
game.json - Optional, configurate scripts order, ignore certain files, etc
Short getters and setters
var tile = re.e('tile');
tile.tileX(1); //sets
tile.tileX(); //gets
Setters can even be used in set()
tile.set('tileX', 2); //sets
Setter with multiple parameters
tile.tile(1, 2); //sets tilex and tiley
//or
tile.set('tile', [1,2]); //samething
Factories in 0.4.2
All components now have a factory method which can be used to create complex entities.
re.c("button")
.factory(function(label, click){
this.label = label;
if(click){
this.on('click', click);
}
});
re.button("Hello", function(){
alert(this.label+" clicked!");
});
//Can be overwritten using the `method` function. A singleton is created below.
re.c("player")
.method(function(){
if(!this.instance){
this.instance = re.e('player');
}
return this.instance;
});
//get player
re.player();
QUnit Testing
All games use QUnit for testing, its light weight and easy to use. Checkout the platform template to see some example tests.
Factories
Factories are used to easily create complex entities. During tests you may need access to a specific type of entity multiple times. Factories make it easy to create any kind of entity at anytime.
Simply create a new factories.js
in the /tests
directory and add something like below.
factory('enemy', function(){
//make a custom coin
this.health = 100;
this.state = 'idle';
//can use normal entity methods
this.on('update', function(){
//something
});
});
//create new enemy entity anywhere in tests
var e = factory('enemy');
eq(e.state, 'idle') //true
//Same as...
var e = re.e('enemy');
e.health = 100;
//etc...
What if you need multiple enemy factories?
//use f for laziness
f('enemy attacking', function(){
this.state = 'attacking';
});
EntityJS Helpers
Some asserts have been added for checking entities, like expectTrigger
, expectFlicker
and expectListener
. For more info check localhost:2345/qunit/qunit.entity.js
.
Input Helpers
Special methods like keypress()
and click()
are available to simulate user input. Check localhost:2345/qunit/qunit.input.js
for more information.
Tile Map Editor
The awesome tiled map editor is now compatible and can be used in your projects.
Simply create a new directory in /assets named levels or anything you like to save your maps in. They can accessed in code like so:
re('level1.tmx')[0]; //assuming the file name is level1.tmx
re('level'); //find all levels that are in the /assets/levels directory
If you are still confused create a new platform game and view levels are used.
Quick Start Guide
First you should install ruby and the entityjs gem.
Now you can create a new game from the platform template:
entityjs new mygame platform
Move into the mygame
directory and play the game:
entityjs server
Open your browser and navigate to localhost:2345
Contributing
Before sending a pull request it would be a good idea to run rspec
and rake jasmine
to make sure all tests pass in both ruby and javascript.
Running rspec will generate a /mygame/ folder with test files. It will be ignored by git so don't worry about it.
Change Log
0.6.0 - Upcoming
- Move to a Nodejs package
- Setup Dox to auto-generate documentation
- Setup grunt to deal with tasks
0.5.0
- Added new group class
- Added new system class
- Removed global entity searching (use groups)