An entity acts as a container for components. They have a unique id and include helper methods for working with their included components. Entities are managed by an EntityManager and are grouped by Archetypes.
reset()
Resets an Entity to an empty state and gets a new unique id.
hasComponent(type: ComponentType) _alias: has
Checks if entity contains a component by type.
hasComponents(...type: ComponentTypes[])
Checks if entity contains every component by type.
addComponent(component: Component)
Adds a component.
TODO....
Components are responsible for storing data. They include a value property and helper methods for attaching and detaching:
onAttach(entity: Entity)
Runs when added or toggled on an entity.
onDetach(entity: Entity)
Runs when removed from entity or when entity is reset (usually when released back into object pool).
A function which returns an array of instantiated components
(...args: any[]) => Component[]Archetypes are responsible for grouping entities by their components. They specify component filters to group on.
include(...componentTypes: ComponentType[])
Grouped entities will contain these component types.
exclude(...componentTypes: ComponentType[])
Grouped entities will not contain these component types.
only(...componentTypes: ComponentType[])
Grouped entities will contain only these componet types.
any(...componentTypes: ComponentType[])
Grouped entities will contain any of these component types.
In conjunction with the supplied filter presets you may also supply any custom filter that adheres to the pattern:
;(entity: Entity<ComponentTypes>) => booleanFilters are only triggered when a change event is detected from the EntityManager. These change events are occur when:
- an entity is added to the manager.
- an entity is removed from the manager.
- an entity is renewed from the manager entity pool.
- an entity is released back into the manager entity pool.
- a component is added to a managed entity.
- a component is removed from a managed entity.
- a component is toggled on a managed entity.
NOTE: Changes within component values are not tracked.
All entities and archetypes in a World are managed by the EntityManager. It is responsible for coordinating component change events within entities to archetypes as well as renewing and releasing entities from an object pool.
Generally the EntityManager is only used interally by the World.
Systems perform logic based on entities and their components. Generally select which entities they are interested in from archetypes. All Systems include an update method.
The world is the user facing interface responsible for registering systems and archetypes, creating and removing entities, and most importantly updating systems.