# dartemis

**Repository Path**: mirrors_davidB/dartemis

## Basic Information

- **Project Name**: dartemis
- **Description**: A Dart port of the Artemis Entity System Framework
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2020-08-08
- **Last Updated**: 2026-06-20

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

dartemis
========

[![](https://drone.io/denniskaselow/dartemis/status.png)](https://drone.io/denniskaselow/dartemis/latest)

A Dart port of the Entity System Framework **Artemis**.

The original has been written in Java by Arni Arent and Tiago Costa and can be found here: http://gamadu.com/artemis with the source available here: https://code.google.com/p/artemis-framework/

Ports for other languages are also available:

* C#: https://github.com/thelinuxlich/artemis_CSharp 
* Python: https://github.com/kernhanda/PyArtemis

Some useful links about what an Entity System/Entity Component System is:

* http://piemaster.net/2011/07/entity-component-artemis/
* http://t-machine.org/index.php/2007/09/03/entity-systems-are-the-future-of-mmog-development-part-1/ 
* http://www.richardlord.net/blog/what-is-an-entity-framework

Getting started
===============

1\. Add dartemis to your project by adding it to your **pubspec.yaml**  
2\. Import it in your project:

```dart
import 'package:dartemis/dartemis.dart';
```
3\. Create a world:

```dart
World world = new World();
```
4\. Create entities, add components to them and finally add those entities to the world. Entities with different components will be processed by different systems:

```dart
Entity entity  = world.createEntity();
entity.addComponent(new Position(world, 0, 0));
entity.addComponent(new Velocity(world, 1, 1));
entity.addToWorld();
```
A `Component` is a pretty simple structure and should not contain any logic:

```dart
class Position extends Component {
    num x, y;

    Position._();
    factory Position(num x, num y) {
        Position position = new Component(Position, _constructor);
        position.x = x;
        position.y = y;
        return position;
    }
    static Position _constructor() => new Position._();
}
```
By using a factory constructor and calling the factory constructor in `Component` the system is able to reuse destroyed components and no garbage collection will occur as long as the world exists. For more information about why this is done you might want to read this article: [Free Lists For Predictable Game Performance](http://dartgamedevs.org/blog/2012/11/02/Free-Lists-For-Predictable-Game-Performance/) 

5\. Define a systems that should process your entities. The `Aspect` defines which components an entity needs to have in order to be processed by the system:

```dart
class MovementSystem extends EntityProcessingSystem {
    ComponentMapper<Position> positionMapper;
    ComponentMapper<Velocity> velocityMapper;
  
    MovementSystem() : super(Aspect.getAspectForAllOf([Position, Velocity]));
  
    void initialize() {
      positionMapper = new ComponentMapper<Position>(Position, world);
      velocityMapper = new ComponentMapper<Velocity>(Velocity, world);
    }
  
    void processEntity(Entity entity) {
      Position position = positionMapper.get(entity);
      Velocity vel = velocityMapper.get(entity);  
      position.x += vel.x;
      position.y += vel.y;
    }
}
```  
6\. Add your system to the world:

```dart  
world.addSystem(new MovementSystem());
```
7\. Initialize the world:

```dart
world.initialize();
```
8\. In your game loop you then process your systems:

```dart
world.process();
```
If your game logic requires a delta you can set it by calling:
```dart
world.delta = delta;
```

Documentation
=============
API
---
[Reference Manual](http://denniskaselow.github.com/dartemis/docs/dartemis.html)

Example Games using dartemis
============================
darteroids
----------
An very simple example included in the example folder of dartemis:  
[Source Code](https://github.com/denniskaselow/dartemis/tree/master/example/web)  
[Playable version](http://denniskaselow.github.com/dartemis/example/darteroids/darteroids.html)

GitHub Space Off
----------------
A game originally created for the GitHub Game Off 2012  
[Source Code](https://github.com/denniskaselow/game-off-2012)  
[Playable version](http://denniskaselow.github.com/game-off-2012/)

Contributors
============
* [David Bernard](https://github.com/davidB) - EntityStateMachine and other additions