System.md

retro-engine / Exports / System

Class: System

Represents a system that acts on a specific component. Systems are added automatically to the engine when a component is added to an entity.

Note that currently for a system to be added automatically its name must be the same as the component it acts on.

Example

An example user-defined game object:

import VelocityComponent from "./Velocity.js";
class Velocity extends engine.System {
  static arg_names = [];
  static arg_types = [];
  component = VelocityComponent;
  
  update(entities) {
    entities.forEach(entity => {
        entity.Position.x += entity.Velocity.x;
        entity.Position.y += entity.Velocity.y;
    });
  }
}

Table of contents

Constructors

• constructor

Properties

• component

Methods

• update

Constructors

constructor

• new System() The constructor function can be freely overridden and additional properties can be added to the system, as long as the arg_names and arg_types are updated accordingly.

Properties

component

• Abstract component: ComponentType<Component>

The component that this system acts on.

Defined in

src/ecs.ts:205

Methods

update

▸ Abstract update(entities): void

This function is run once per frame.

Parameters

Name	Type	Description
entities	Set<GameObjectBase>	The list of entities that the system acts on.

Returns

void

Defined in

src/ecs.ts:211