Wraps entt::registry with a safer, callback-aware API. More...

#include <Registry.hpp>

Public Member Functions
Entity	CreateEntity ()
	Creates a new entity.
void	DestroyEntity (const Entity entity)
	Destroys an entity if it is valid.
bool	EntityValid (const Entity entity)
	Checks whether an entity is alive in the registry.
template<typename Component, typename... Args>
const Component *	Emplace (const Entity entity, Args &&... args)
	Adds a component to an entity.
template<typename Component, typename... Args>
const Component &	EmplaceOrReplace (const Entity entity, Args &&... args)
	Adds or replaces a component on an entity.
template<typename Component>
bool	Patch (const Entity entity, const std::function< void(Component &)> &func)
	Applies a function to an existing component in place.
template<typename Component>
const Component *	Get (const Entity entity)
	Gets a pointer to a component on an entity.
template<typename... Components>
bool	HasAny (const Entity entity)
	Checks whether an entity has at least one of the given components.
template<typename... Components>
bool	HasAll (const Entity entity)
	Checks whether an entity has all of the given components.
template<typename Component, typename... Args>
const Component *	Replace (const Entity entity, Args &&... args)
	Replaces an existing component on an entity.
template<typename Component>
void	Remove (const Entity entity)
	Removes a component from an entity.
template<typename Component>
void	ClearComponents ()
	Removes all instances of a component type from every entity.
template<typename... Components>
auto	GetView ()
	Returns a view over all entities that have the given components.
template<typename... Owned, typename... Get, typename... Exclude>
auto	GetGroup (entt::get_t< Get... > get=entt::get_t{}, entt::exclude_t< Exclude... > exclude=entt::exclude_t{})
	Returns a group over entities with the specified owned and non-owned components.
template<typename Component>
void	Sort (const std::function< bool(const Component &a, const Component &b)> &comparitor)
	Sorts a component pool using a comparator.
template<typename... Owned, typename... Get, typename... Exclude>
void	SortGroup (const std::function< bool(const Entity &a, const Entity &b)> &comparitor, entt::get_t< Get... > get=entt::get_t{}, entt::exclude_t< Exclude... > exclude=entt::exclude_t{})
	Sorts a group's entities using an entity comparator.
template<typename Component>
u32	OnConstruct (const std::function< void(Component &component, const Entity entity)> &callback)
	Registers a callback invoked when a component of the given type is constructed.
template<typename Component>
u32	OnUpdate (const std::function< void(Component &component, const Entity entity)> &callback)
	Registers a callback invoked when a component of the given type is updated.
template<typename Component>
u32	OnDestroy (const std::function< void(Component &component, const Entity entity)> &callback)
	Registers a callback invoked just before a component of the given type is destroyed.
template<typename Component>
void	RemoveConstructCallback (const u32 callbackId)
	Removes a previously registered construction callback.
template<typename Component>
void	RemoveUpdateCallback (const u32 callbackId)
	Removes a previously registered update callback.
template<typename Component>
void	RemoveDestroyCallback (const u32 callbackId)
	Removes a previously registered destruction callback.
entt::registry &	GetRegistry ()
	Returns a reference to the underlying entt registry.

Detailed Description

Wraps entt::registry with a safer, callback-aware API.

Provides typed component operations and supports registering callbacks for component construction, update, and destruction events. All callbacks are identified by a u32 ID so they can be individually removed.

Member Function Documentation

◆ ClearComponents()

template<typename Component>

void Registry::ClearComponents ( )

inline

Removes all instances of a component type from every entity.

Template Parameters

Component Component type to clear

◆ CreateEntity()

Entity Registry::CreateEntity ( )

Creates a new entity.

Returns: The newly created entity

◆ DestroyEntity()

void Registry::DestroyEntity ( const Entity entity )

Destroys an entity if it is valid.

Does nothing if the entity is not valid.

Parameters

entity Entity to destroy

◆ Emplace()

template<typename Component, typename... Args>

const Component * Registry::Emplace	(	const Entity	entity,
		Args &&...	args )

inline

Adds a component to an entity.

Does nothing and returns nullptr if the entity already has this component.

Template Parameters

Component	Component type to add
Args	Component constructor argument types

Parameters

entity	Target entity
args	Component constructor arguments

Returns: Pointer to the new component, or nullptr if it already existed

◆ EmplaceOrReplace()

template<typename Component, typename... Args>

const Component & Registry::EmplaceOrReplace	(	const Entity	entity,
		Args &&...	args )

inline

Adds or replaces a component on an entity.

If the component already exists it is replaced in place; otherwise it is created.

Template Parameters

Component	Component type
Args	Component constructor argument types

Parameters

entity	Target entity
args	Component constructor arguments

Returns: Reference to the component

◆ EntityValid()

bool Registry::EntityValid ( const Entity entity )

Checks whether an entity is alive in the registry.

Parameters

entity Entity to check

Returns: True if the entity is valid

◆ Get()

template<typename Component>

const Component * Registry::Get ( const Entity entity )

inline

Gets a pointer to a component on an entity.

Template Parameters

Component Component type

Parameters

entity Target entity

Returns: Pointer to the component, or nullptr if the entity does not have it

◆ GetGroup()

template<typename... Owned, typename... Get, typename... Exclude>

auto Registry::GetGroup	(	entt::get_t< Get... >	get = entt::get_t{},
		entt::exclude_t< Exclude... >	exclude = entt::exclude_t{} )

inline

Returns a group over entities with the specified owned and non-owned components.

Owned components are stored contiguously for cache-friendly iteration. Non-owned components are fetched via Get. Excluded components filter entities out.

Template Parameters

Owned	Component types owned (and sorted) by the group
Get	Additional component types to fetch but not own
Exclude	Component types that disqualify an entity from the group

Parameters

get	entt::get_t list of non-owned components to include
exclude	entt::exclude_t list of components to exclude

Returns: entt group over the matching entities

◆ GetRegistry()

entt::registry & Registry::GetRegistry ( )

Returns a reference to the underlying entt registry.

Prefer the typed API above. This escape hatch exists for interop with entt APIs not yet wrapped by Registry.

Returns: Reference to the raw entt::registry

◆ GetView()

template<typename... Components>

auto Registry::GetView ( )

inline

Returns a view over all entities that have the given components.

Components are exposed as const references inside the view.

Template Parameters

Components Component types to include in the view

Returns: entt view over the matching entities

◆ HasAll()

template<typename... Components>

bool Registry::HasAll ( const Entity entity )

inline

Checks whether an entity has all of the given components.

Template Parameters

Components Component types to check

Parameters

entity Target entity

Returns: True if the entity has every specified component

◆ HasAny()

template<typename... Components>

bool Registry::HasAny ( const Entity entity )

inline

Checks whether an entity has at least one of the given components.

Template Parameters

Components Component types to check

Parameters

entity Target entity

Returns: True if the entity has any of the specified components

◆ OnConstruct()

template<typename Component>

u32 Registry::OnConstruct ( const std::function< void(Component &component, const Entity entity)> & callback )

inline

Registers a callback invoked when a component of the given type is constructed.

Multiple callbacks can be registered for the same component type. The returned ID can be used with RemoveConstructCallback to unregister.

Template Parameters

Component Component type to observe

Parameters

callback Function receiving the new component and the owning entity

Returns: Callback ID

◆ OnDestroy()

template<typename Component>

u32 Registry::OnDestroy ( const std::function< void(Component &component, const Entity entity)> & callback )

inline

Registers a callback invoked just before a component of the given type is destroyed.

Multiple callbacks can be registered for the same component type. The returned ID can be used with RemoveDestroyCallback.

Template Parameters

Component Component type to observe

Parameters

callback Function receiving the component about to be destroyed and its entity

Returns: Callback ID

◆ OnUpdate()

template<typename Component>

u32 Registry::OnUpdate ( const std::function< void(Component &component, const Entity entity)> & callback )

inline

Registers a callback invoked when a component of the given type is updated.

Triggered by Patch and Replace. Multiple callbacks can be registered for the same component type. The returned ID can be used with RemoveUpdateCallback.

Template Parameters

Component Component type to observe

Parameters

callback Function receiving the updated component and the owning entity

Returns: Callback ID

◆ Patch()

template<typename Component>

bool Registry::Patch	(	const Entity	entity,
		const std::function< void(Component &)> &	func )

inline

Applies a function to an existing component in place.

Triggers update callbacks. Does nothing and returns false if the entity does not have the component.

Template Parameters

Component Component type

Parameters

entity	Target entity
func	Function to apply to the component

Returns: True if the component existed and was patched

◆ Remove()

template<typename Component>

void Registry::Remove ( const Entity entity )

inline

Removes a component from an entity.

Does nothing if the entity does not have the component.

Template Parameters

Component Component type to remove

Parameters

entity Target entity

◆ RemoveConstructCallback()

template<typename Component>

void Registry::RemoveConstructCallback ( const u32 callbackId )

inline

Removes a previously registered construction callback.

Disconnects the underlying signal if no more callbacks remain for this type.

Template Parameters

Component Component type the callback was registered for

Parameters

callbackId ID returned by OnConstruct

◆ RemoveDestroyCallback()

template<typename Component>

void Registry::RemoveDestroyCallback ( const u32 callbackId )

inline

Removes a previously registered destruction callback.

Disconnects the underlying signal if no more callbacks remain for this type.

Template Parameters

Component Component type the callback was registered for

Parameters

callbackId ID returned by OnDestroy

◆ RemoveUpdateCallback()

template<typename Component>

void Registry::RemoveUpdateCallback ( const u32 callbackId )

inline

Removes a previously registered update callback.

Disconnects the underlying signal if no more callbacks remain for this type.

Template Parameters

Component Component type the callback was registered for

Parameters

callbackId ID returned by OnUpdate

◆ Replace()

template<typename Component, typename... Args>

const Component * Registry::Replace	(	const Entity	entity,
		Args &&...	args )

inline

Replaces an existing component on an entity.

Does nothing and returns nullptr if the entity does not have the component.

Template Parameters

Component	Component type
Args	Component constructor argument types

Parameters

entity	Target entity
args	Component constructor arguments

Returns: Pointer to the replaced component, or nullptr if it did not exist

◆ Sort()

template<typename Component>

void Registry::Sort ( const std::function< bool(const Component &a, const Component &b)> & comparitor )

inline

Sorts a component pool using a comparator.

The sort order affects the iteration order of views over this component.

Template Parameters

Component Component type whose pool is sorted

Parameters

comparitor Comparator receiving two const component references

◆ SortGroup()

template<typename... Owned, typename... Get, typename... Exclude>

void Registry::SortGroup	(	const std::function< bool(const Entity &a, const Entity &b)> &	comparitor,
		entt::get_t< Get... >	get = entt::get_t{},
		entt::exclude_t< Exclude... >	exclude = entt::exclude_t{} )

inline

Sorts a group's entities using an entity comparator.

Affects the iteration order of the group. The group is identified by the same owned/get/exclude template parameters used to create it.

Template Parameters

Owned	Owned component types of the group
Get	Non-owned component types of the group
Exclude	Excluded component types of the group

Parameters

comparitor	Comparator receiving two entity references
get	entt::get_t matching the group's get list
exclude	entt::exclude_t matching the group's exclude list

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

src/Engine/Registry.hpp
src/Engine/Registry.cpp

Public Member Functions

Detailed Description

Member Function Documentation

◆ ClearComponents()

◆ CreateEntity()

◆ DestroyEntity()

◆ Emplace()

◆ EmplaceOrReplace()

◆ EntityValid()

◆ Get()

◆ GetGroup()

◆ GetRegistry()

◆ GetView()

◆ HasAll()

◆ HasAny()

◆ OnConstruct()

◆ OnDestroy()

◆ OnUpdate()

◆ Patch()

◆ Remove()

◆ RemoveConstructCallback()

◆ RemoveDestroyCallback()

◆ RemoveUpdateCallback()

◆ Replace()

◆ Sort()

◆ SortGroup()