The EntityManager is the code that manages all Entities and Components in the game. Normally the game will instantiate EntityManager, and then use it to create and control all of its Entities. More...

#include <entity_manager.h>

Detailed Description

The EntityManager is the code that manages all Entities and Components in the game. Normally the game will instantiate EntityManager, and then use it to create and control all of its Entities.

The main uses for this class are:

Creating/destroying new Entities.
Keeping track of all Components.
Spawning and populating new Components from data.
Updating Entities/Components. (Usually done once per frame.)

Public Types
typedef VectorPool< Entity >	EntityStorageContainer
	This is used to track all Entities stored by the EntityManager.

Public Member Functions
	EntityManager ()
	Constructor for the EntityManager.

const CorgiVersion *	GetCorgiVersion ()
	Returns the version of the Corgi entity library.

template<typename T >
T *	GetComponentData (const EntityRef &entity)
	Helper function for marshalling data from a Component. More...

template<typename T >
const T *	GetComponentData (const EntityRef &entity) const
	A helper function for marshalling data from a Component. More...

template<typename T >
T *	GetComponent ()
	A helper function for getting a particular Component, given the Component's data type. More...

template<typename T >
const T *	GetComponent () const
	A helper function for getting a particular Component, given the Component's data type. More...

template<typename T >
void	AddEntityToComponent (EntityRef entity)
	A helper function for adding a Component to an Entity, given its data type. More...

ComponentInterface *	GetComponent (ComponentId id)
	A helper function for getting a particular Component, given the component ID. More...

const ComponentInterface *	GetComponent (ComponentId id) const
	A helper function for getting a particular Component, given a component ID. More...

size_t	ComponentCount () const
	Returns the number of components that have been registered with the entity manager. More...

template<typename T >
ComponentId	GetComponentId ()
	A helper function to get the component ID for a given Component. More...

EntityRef	AllocateNewEntity ()
	Allocates a new Entity (that is registered with no Components). More...

void	DeleteEntity (EntityRef entity)
	Deletes an Entity by removing it from the EntityManager's list and clearing any Component data associated with it. More...

void	DeleteEntityImmediately (EntityRef entity)
	Instantly deletes an Entity. More...

template<typename T >
ComponentId	RegisterComponent (T *new_component)
	Registers a new Component with the EntityManager. More...

void	RemoveAllComponents (EntityRef entity)
	Removes all Components for an Entity, destroying any data associated with it. More...

void	UpdateComponents (WorldTime delta_time)
	Iterates through all the registered Components and causes them to update. More...

void	Clear ()
	Clears all data from all Components, empties the list of Components themselves, and then empties the list of Entities. This basically resets the EntityManager into its original state.

EntityStorageContainer::Iterator	begin ()
	Returns an iterator to the beginning of the active Entities. This is suitable for iterating over every active Entity. More...

EntityStorageContainer::Iterator	end ()
	Returns an iterator to the last of the active Entities. More...

void	set_entity_factory (EntityFactoryInterface *entity_factory)
	Registers an instance of the EntityFactoryInterface as the factory object to be used when Entities are created from arbitrary data. The EntityFactory is responsible for parsing arbitrary data and correctly transforming it into an Entity. More...

EntityRef	CreateEntityFromData (const void *data)
	Creates an Entity from arbitrary data. This is normally invoked only by classes that inherit from EntityFactoryInterface. More...

void	AddEntityToComponent (EntityRef entity, ComponentId component_id)
	Registers an Entity with a Component. This causes the Component to allocate data for the Entity and includes the Entity in that Component's update routines. More...

void	DeleteMarkedEntities ()
	Deletes all the Entities that are marked for deletion. More...

Member Function Documentation

template<typename T >

void corgi::EntityManager::AddEntityToComponent ( EntityRef entity )

inline

A helper function for adding a Component to an Entity, given its data type.

Note: Asserts if the Component does not exist.

Template Parameters

T	The data type of the Component that should have the Entity added to it.

Parameters

[in] entity An EntityRef that points to the Entity that is being added to the Component.

void corgi::EntityManager::AddEntityToComponent	(	EntityRef	entity,
		ComponentId	component_id
	)

Registers an Entity with a Component. This causes the Component to allocate data for the Entity and includes the Entity in that Component's update routines.

Parameters

[in]	entity	An EntityRef that points to the Entity that should be registered with the Component.
[in]	component_id	The component ID of the Component that should be registered with the Entity.

EntityRef corgi::EntityManager::AllocateNewEntity ( )

Allocates a new Entity (that is registered with no Components).

Returns: Returns an EntityRef that points to the new Entity.

EntityStorageContainer::Iterator corgi::EntityManager::begin ( )

inline

Returns an iterator to the beginning of the active Entities. This is suitable for iterating over every active Entity.

Returns: Returns a std::iterator to the first active Entity.

size_t corgi::EntityManager::ComponentCount ( ) const

inline

Returns the number of components that have been registered with the entity manager.

Returns: The total number of components that are currently registered with the entity manager.

EntityRef corgi::EntityManager::CreateEntityFromData ( const void * data )

Creates an Entity from arbitrary data. This is normally invoked only by classes that inherit from EntityFactoryInterface.

Any class implementing CreateEntityFromData should establish the input format for the 'data' and a way to parse that input 'data' into an Entity.

Parameters

[in] data A void pointer to the data to be used to create the Entity.

Returns: Returns an EntityRef that points to the newly created Entity.

void corgi::EntityManager::DeleteEntity ( EntityRef entity )

Deletes an Entity by removing it from the EntityManager's list and clearing any Component data associated with it.

Note: Deletion is deferred until the end of the frame. If you want to delete something instantly, use DeleteEntityImmediately.

Parameters

[in] entity An EntityRef that points to the Entity that will be deleted at the end of the frame.

void corgi::EntityManager::DeleteEntityImmediately ( EntityRef entity )

Instantly deletes an Entity.

Note: In general, you should use DeleteEntity (which defers deletion until the end of the update cycle) unless you have a very good reason for doing so.

Parameters

[in] entity An EntityRef that points to the Entity that will be immediately deleted.

void corgi::EntityManager::DeleteMarkedEntities ( )

Deletes all the Entities that are marked for deletion.

Warning: Do NOT call this function during any form of Entity update!

EntityStorageContainer::Iterator corgi::EntityManager::end ( )

inline

Returns an iterator to the last of the active Entities.

Returns: Returns a std::iterator to the last active Entity.

template<typename T >

T* corgi::EntityManager::GetComponent ( )

inline

A helper function for getting a particular Component, given the Component's data type.

Note: Asserts if the Component does not exist.

Template Parameters

T	The data type of the Component to be returned.

Returns: Returns a pointer to the Component given its data type.

template<typename T >

const T* corgi::EntityManager::GetComponent ( ) const

inline

A helper function for getting a particular Component, given the Component's data type.

Note: Asserts if the Component does not exist.

Template Parameters

T	The data type of the Component to be returned.

Returns: Returns a const pointer to the Component given its datatype.

ComponentInterface* corgi::EntityManager::GetComponent ( ComponentId id )

inline

A helper function for getting a particular Component, given the component ID.

Parameters

[in] id The component ID for the desired Component.

Note: Asserts if the id is less than kMaxComponentCount.

Returns: Returns a pointer to the Component at the given id, which inherits from the ComponentInterface.

const ComponentInterface* corgi::EntityManager::GetComponent ( ComponentId id ) const

inline

A helper function for getting a particular Component, given a component ID.

Parameters

[in] id The component ID for the desired Component.

Note: Asserts if the id is less than kMaxComponentCount.

Returns: Returns a const pointer to the Component at the given id, which inherits from the ComponentInterface.

template<typename T >

T* corgi::EntityManager::GetComponentData ( const EntityRef & entity )

inline

Helper function for marshalling data from a Component.

Template Parameters

T	The data type of the Component data to be returned.

Parameters

[in] entity The Entity associated with the desired data.

Returns: Returns a pointer to the Component data, or returns a nullptr if no such data exists.

template<typename T >

const T* corgi::EntityManager::GetComponentData ( const EntityRef & entity ) const

inline

A helper function for marshalling data from a Component.

Template Parameters

T	The data type of the Component data to be returned.

Parameters

[in] entity The Entity associated with the desired data.

Returns: Returns a const pointer to the Component data, or returns a nullptr if no such data exists.

template<typename T >

ComponentId corgi::EntityManager::GetComponentId ( )

inline

A helper function to get the component ID for a given Component.

Template Parameters

T	The data type of the Component whose ID should be returned.

Returns: Returns the component ID for a given Component.

template<typename T >

ComponentId corgi::EntityManager::RegisterComponent ( T * new_component )

inline

Registers a new Component with the EntityManager.

Template Parameters

T	The data type of the Component that is being registered with the EntityManager.

Parameters

[in] new_component A Component to be registered with to the EntityManager.

Note: The new_component must inherit from the ComponentInterface.

Returns: Returns the component ID for the new Component.

void corgi::EntityManager::RemoveAllComponents ( EntityRef entity )

Removes all Components for an Entity, destroying any data associated with it.

Note: Normally called by EntityManager prior to deleting an Entity.

Parameters

[in] entity An EntityRef that points to the Entity whose Components should be removed.

void corgi::EntityManager::set_entity_factory ( EntityFactoryInterface * entity_factory )

inline

Registers an instance of the EntityFactoryInterface as the factory object to be used when Entities are created from arbitrary data. The EntityFactory is responsible for parsing arbitrary data and correctly transforming it into an Entity.

Note: This should be set before attempting to load Entities from data files.

Parameters

[in] entity_factory A pointer to a class that inherits from the EntityFactoryInterface, which will be registered with the EntityManager.

void corgi::EntityManager::UpdateComponents ( WorldTime delta_time )

Iterates through all the registered Components and causes them to update.

Parameters

[in] delta_time A WorldTime that represents the timestep since the last update.

The documentation for this class was generated from the following file:

entity_manager.h

Detailed Description

Public Types

Public Member Functions

Member Function Documentation