Entities and Components

TODO

Table of contents

1. Entity
   1. construct new()
   2. addComponent(component)
   3. getComponent(type)
   4. getComponentSuper(type)
   5. deleteComponent(type)
   6. components
   7. deleted
   8. delete()
   9. name
   10. name=(n)
   11. tag
   12. tag=(t)
   13. static init
   14. static update(dt)
   15. static entitiesWithTag(tag)
   16. static entities
   17. static print()
2. Component
   1. construct new()
   2. initialize()
   3. finalize()
   4. update(dt)
   5. owner

Entity

Entry point into the Entity Component system, allowing you to create entities and add components to them. Entity itself manages the entities.

construct new()

Creates a new entity, visible to the rest of the game in the next update.

addComponent(component)

Adds component to the entity.

getComponent(type)

Get a component of a matching type.

getComponentSuper(type)

Get a component of a matching super class type. Slow! Use getComponent(type) when possible

deleteComponent(type)

Will mark the component for removal at the end of the update

components

Get all to components

deleted

Checks if the entity is marked for removal. Set reference to this entity to null if true, so the the GC can delete the object

delete()

Will mark the entity for removal at the end of the update

name

Components can have names. This makes debugging much easier

name=(n)

tag

Generic tag. Used as a bit-flag when getting entities of certain type.

tag=(t)

static init

Call from the initialize() function of you entry point (game class)

static update(dt)

Call from the update() function of you entry point (game class). Updates the all entities and their components. Add/removes entities and components.

static entitiesWithTag(tag)

Get all the entities where the tag matches (has a bit overlap) with a given tag.

static entities

Access to all the entities active in the game.

static print()

Does a formatted print of all the entities and their components. Override the toString property on the component to make it more informative

Component

A base class for components that can be added to the entities.

construct new()

Creates a new component. Make sure to call super() when inheriting from this class. Other components might still not be available on the owning entity.

initialize()

Called right before the first update. Good place to query and cache other components.

finalize()

Called when the component/entity is deleted. Set any references to other entities and components to null.

update(dt)

Called once per update with delta time. Put your logic here.

owner

The Entity object that owns this component