Template-based storage container for components of a specific type. More...

#include <ComponentStorage.hpp>

Inheritance diagram for vex::ComponentStorage< T >:

Public Member Functions
bool	has (Entity entity) const
	Checks if the given entity has a component of type T.
template<typename... Args>
T &	add_or_replace (Entity entity, Args &&... args)
	Adds or replaces a component for an entity.
void	remove (Entity entity)
	Removes the component from an entity.
T &	get (Entity entity)
	Retrieves a reference to the component for an entity.
void	entity_destroyed (Entity entity) override
	Called by the Registry when an entity is destroyed.
void	on_create (std::function< void(Entity, T &)> cb)
	Registers a callback to be invoked when a component is created.
void	on_destroy (std::function< void(Entity, T &)> cb)
	Registers a callback to be invoked when a component is destroyed.
const std::vector< Entity > &	get_entities () const
	Returns the list of all entities that have this component type.
Public Member Functions inherited from vex::IComponentStorage
virtual	~IComponentStorage ()=default
	Virtual destructor for proper cleanup of derived classes.

Private Attributes
std::vector< T >	m_components
	Dense array of component instances, cache-optimized for iteration.
std::vector< Entity >	m_indexToEntity
	Maps component storage index to the entity that owns the component.
std::vector< size_t >	m_entityToIndex
	Maps entity ID to the component storage index, or -1 if not present.
std::vector< std::function< void(Entity, T &)> >	m_onCreate
	Callbacks invoked when a component is created for an entity.
std::vector< std::function< void(Entity, T &)> >	m_onDestroy
	Callbacks invoked when a component is destroyed for an entity.

Detailed Description

template<typename T>
class vex::ComponentStorage< T >

Template-based storage container for components of a specific type.

ComponentStorage manages all instances of a particular component type across all entities that possess it. It uses a dense packing strategy (packed array) to maintain cache-friendly memory layout while supporting efficient entity lookups.

Template Parameters

T	The component type to be stored.

Note

This class maintains three parallel data structures:

m_components: Dense array of actual component instances
m_indexToEntity: Mapping from component index to entity ID
m_entityToIndex: Mapping from entity ID to component index

Definition at line 20 of file ComponentStorage.hpp.

Member Function Documentation

◆ add_or_replace()

template<typename T>

template<typename... Args>

T & vex::ComponentStorage< T >::add_or_replace	(	Entity	entity,
		Args &&...	args )

inline

Adds or replaces a component for an entity.

Template Parameters

Args	Parameter types forwarded to the component constructor.

Parameters

entity	The entity to add/replace the component for.
args	Arguments forwarded to the component's constructor.

Returns: Reference to the newly added or replaced component.

If the entity already has the component, it is replaced in-place. If not, a new component is created and all onCreate callbacks are invoked.

Definition at line 50 of file ComponentStorage.hpp.

◆ entity_destroyed()

template<typename T>

void vex::ComponentStorage< T >::entity_destroyed ( Entity entity )

inlineoverridevirtual

Called by the Registry when an entity is destroyed.

Parameters

entity The entity being destroyed.

Invokes the remove() method to clean up the component and invoke callbacks.

Implements vex::IComponentStorage.

Definition at line 108 of file ComponentStorage.hpp.

◆ get()

template<typename T>

T & vex::ComponentStorage< T >::get ( Entity entity )

inline

Retrieves a reference to the component for an entity.

Parameters

entity The entity whose component to retrieve.

Returns: Mutable reference to the component.

Precondition: The entity must have the component (checked via assert in debug builds).

Definition at line 100 of file ComponentStorage.hpp.

◆ get_entities()

template<typename T>

const std::vector< Entity > & vex::ComponentStorage< T >::get_entities ( ) const

inline

Returns the list of all entities that have this component type.

Returns: Const reference to the vector of entities.

Definition at line 124 of file ComponentStorage.hpp.

◆ has()

template<typename T>

bool vex::ComponentStorage< T >::has ( Entity entity ) const

inline

Checks if the given entity has a component of type T.

Parameters

entity The entity to check.

Returns: True if the entity has the component, false otherwise.

Definition at line 38 of file ComponentStorage.hpp.

◆ on_create()

template<typename T>

void vex::ComponentStorage< T >::on_create ( std::function< void(Entity, T &)> cb )

inline

Registers a callback to be invoked when a component is created.

Parameters

cb	The callback function to register.

Callback is invoked with the entity and component reference.

Definition at line 115 of file ComponentStorage.hpp.

◆ on_destroy()

template<typename T>

void vex::ComponentStorage< T >::on_destroy ( std::function< void(Entity, T &)> cb )

inline

Registers a callback to be invoked when a component is destroyed.

Parameters

cb	The callback function to register.

Callback is invoked with the entity and component reference.

Definition at line 120 of file ComponentStorage.hpp.

◆ remove()

template<typename T>

void vex::ComponentStorage< T >::remove ( Entity entity )

inline

Removes the component from an entity.

template<typename T>

std::vector<std::function<void(Entity, T&)> > vex::ComponentStorage< T >::m_onDestroy

private

Callbacks invoked when a component is destroyed for an entity.

Definition at line 32 of file ComponentStorage.hpp.

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

Core/include/components/ECS/ComponentStorage.hpp

Public Member Functions

Private Attributes

Detailed Description

Member Function Documentation

◆ add_or_replace()

◆ entity_destroyed()

◆ get()

◆ get_entities()

◆ has()

◆ on_create()

◆ on_destroy()

◆ remove()

Member Data Documentation

◆ m_components

◆ m_entityToIndex

◆ m_indexToEntity

◆ m_onCreate

◆ m_onDestroy