fast_ecs 0.1.0

Simple and fast Entity-Component-System (ECS) library written in Dart.

example/README.md

Fast ECS Examples

Simple and fast Entity-Component-System (ECS) library written in Dart.

Components

Creating a VelocityComponent class

class VelocityComponent extends Component {
  double velocity = 2;
}

Creating a TransformComponent class

class TransformComponent extends Component {
  double rotation = 0.0;
  double scale = 0.5;
}

Systems

Creating a RotationSystem class

class RotationSystem extends UpdateEcsSystem {
  late List<TransformComponent> transformComponents; // quick link
  late List<VelocityComponent> velocityComponents; // quick link

  @override
  void init(ecs, Signature signature) {
    transformComponents = ecs.getComponentList<TransformComponent>();
    velocityComponents = ecs.getComponentList<VelocityComponent>();
  }

  @override
  void update(double deltaTime, SetEntity entities) {
    for (var i = 0; i < entities.size; i++) {
      Entity entity = entities.get(i);
      TransformComponent transform = transformComponents[entity];
      VelocityComponent velocity = velocityComponents[entity];
      transform.rotation += velocity.velocity * deltaTime;
    }
  }
}

Entity Component System

Creating a Ecs class

Ecs ecs = Ecs(maxEntity: maxEntity, maxComponents: 8);
// register components
ComponentId transformId = ecs.registerComponent<TransformComponent>((index) => TransformComponent(), maxEntity);
ComponentId velocityId = ecs.registerComponent<VelocityComponent>((index) => VelocityComponent(), maxEntity);
var rotationSystemSignature = ecs.createSignature([transformId, velocityId]);
// register RotationSystem with signature
ecs.registerSystem<RotationSystem>(() => RotationSystem(), signature: rotationSystemSignature);

Entity

Creating a Entity

Entity entity = ecs.createEntity();
ecs.addComponent(transformId, entity);
ecs.addComponent(velocityId, entity);

Usage

update ECS

ecs.update(deltaTime);

render ECS

void _render(EcsSystem system, Uint16Set entities) {
  if (system is DrawSystem) {
    system.draw(batch, entities);
  }
}

void render() {
  ecs.forEach(_render);
}