engine.ecs package

Submodules

engine.ecs.component module

class engine.ecs.component.Component

Bases: abc.ABC

Abstract class for a Component which stores data and nothing else.

engine.ecs.entity module

class engine.ecs.entity.Entity

Bases: object

Simple Universally Unique Identifiers (UUIDs) used to identify this Entity in the Entity Manager.

static create_component_debug(component)
render_debug(entity_manager)

engine.ecs.entity_listener module

class engine.ecs.entity_listener.EntityListener

Bases: abc.ABC

abstract entity_added(entity)

This method gets called when an entity is added to a manager this listener is registered to.

Parameters

entity – The entity that was added

abstract entity_removed(entity, components)

This method gets called when an entity is removed from a manager this listener is registered to.

Parameters

  • entity (Entity) – The entity that was removed

  • components (dict) – The components that were attached to the entity in the system. {type(component): component}

engine.ecs.entity_manager module

class engine.ecs.entity_manager.EntityManager

Bases: object

Class responsible for handling Entities, their Components and Systems.

add_component_to_entity(entity, *components)

Applies given Component instances to a given Entity instance.

Parameters

  • entity (Entity) – The Entity to have components added to.

  • components – The Component instances to be added to the entity.

Returns

None

add_entity(entity)

Adds an existing Entity instance to the manager and returns it.

Parameters

entity – The Entity instance to be added

Returns

Entity

add_listener(listener)

Adds a given Listener instance to the Entity Manager.

Parameters

listener (Listener) – The Listener instance to add to the Entity Manager.

Returns

None

add_system(*system)

Adds given System instances to the Entity Manager.

Parameters

system – The System instance to add to the Entity Manager.

Returns

None

create_entity()

Creates a new Entity instance, adds it to the manager and returns it.

Returns

A new Entity instance. Equivalent to creating an instance manually.

Return type

Entity

entity_exists(entity)

Returns True if the given Entity instance is in the entity manager,

Parameters

entity (Entity) – The Entity instance to be checked.

Returns

A boolean representing whether the Entity was found or not.

Return type

bool

get_component_map(component_type)

Returns dictionary of key value pairs where Entity instances are the key and Component instances are the values and the Component instances are of the given Component type.

Parameters

component_type – The type of Component

Returns

A dictionary of Entity instances to their Component instances.

Return type

dict

get_entity_components(entity)

Gets a set of all components attached to the given entity.

Parameters

entity (Entity) – The entity instance to get the components of

Returns

The set of all components attached to the given entity

Return type

set

get_family(*component_types)

Returns entities in the map that have all of the given Component types.

Parameters

component_types – A Set of Component types that you want the Family for.

Returns

The Family of entities that have all of the requested Component types.

Return type

Family

remove_component_from_entity(entity, component_type)

Removes all Component instances of given Component type from given Entity instance.

Parameters

  • entity (Entity) – The Entity to have components removed from

  • component_type – The Component types to removed from the Entity.

Returns

None

remove_entity(entity)

Removes an Entity instance from the Entity Manager.

Parameters

entity (Entity) – The Entity instance to be removed from the Entity Manager.

Returns

A set containing the removed entity’s components

Return type

set

remove_listener(listener)

Removes a given Listener instance from the Entity Manager.

Parameters

listener (Listener) – The Listener instance to remove from the Entity Manager.

Returns

None

remove_system(system)

Removes given System instance from the Entity Manager.

Parameters

system – The System instance to remove from the Entity Manager.

Returns

None

return_entities()

Returns a list of entities.

Returns

A list of all registered entities

Return type

list

update(deltatime)

Updates all systems in the database by calling their update functions. Should be called every tick.

Parameters

deltatime (float) – Time between frames. Can be used for framerate independence.

Returns

None

engine.ecs.family module

class engine.ecs.family.Family(entities)

Bases: object

Data structure for tracking sets of entities that have specific Component types.

set_entities(entities)
Parameters

entities – A set of Entity instances.

Returns

None

engine.ecs.iterator_system module

class engine.ecs.iterator_system.IteratorSystem

Bases: engine.ecs.system.System

Utility class for automatically iterating through a family of entities.

abstract process(deltatime, entity)

The method that performs logic on an entity and its components.

Parameters

  • deltatime (float) – Time between frames. Can be used for framerate independence.

  • entity (Entity) – The Entity instance that is being processed.

Returns

None

update(deltatime)

Automatically iterates through the family of the system.

Returns

None

engine.ecs.system module

class engine.ecs.system.System(priority=0)

Bases: abc.ABC

Abstract class for processing Entity instances.

property priority
abstract update(deltatime)

The update method that is called every tick.

Parameters

deltatime (float) – Time between frames. Can be used for framerate independence.

Returns

None

Module contents