# entity_cool_system

An ECS implementation in crystal

## Installation

1. Add the dependency to your `shard.yml`:

   ```yaml
   dependencies:
     entity_cool_system:
       git: https://git.sceptique.eu/Sceptique/EntityCoolSystem
       branch: master
   ```

2. Run `shards install`

## Usage

```crystal
require "entity_cool_system"

# init the world
world = ECS::World.new

# add custom systems
world << { name: "name_of_a_system", system: new MyScope::Systems::CustomSystem }

world["name_of_a_system"] << new MyScope::Entities::SomeKind("params1")
world["name_of_a_system"] << new MyScope::Entities::SomeKind("params2")
world["name_of_a_system"] << new MyScope::Entities::SomeKind("params3")

# call the systems #init methods
world.init

# maybe infinite loop
100.times do |i|
  # call the systems #update methods
  world.update
end

# call the systems #cleanup methods
world.cleanup
```

First you must define your systems and components.

Systems extend `ECS::System` and may provide `#init`, `#update`, `#cleanup` methods. To do so they also must implement `ECS::System::Init`, `ECS::System::Update`, `ECS::System::Cleanup`.

Components are extending `CS::Component` and they are initialized with an entity as first parameter. A macro `ECS::Components.generate_component` is provided in order to be able to generate new simple component initializer in one line.

You may provide entities generator if needed.

## Development

TODO: Write development instructions here

## Contributing

1. Fork it (<https://git.sceptique.eu/Sceptique/EntityCoolSystem>)
2. Create your feature branch (`git checkout -b my-new-feature`)
3. Commit your changes (`git commit -am 'Add some feature'`)
4. Push to the branch (`git push origin my-new-feature`)
5. Create a new Pull Request

## Contributors

- [Arthur Poulet](https://git.sceptique.eu/Sceptique - creator and maintainer