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- #ifndef ENTT_ENTITY_SIGH_STORAGE_MIXIN_HPP
- #define ENTT_ENTITY_SIGH_STORAGE_MIXIN_HPP
-
- #include <utility>
- #include "../config/config.h"
- #include "../core/any.hpp"
- #include "../signal/sigh.hpp"
- #include "fwd.hpp"
-
- namespace entt {
-
- /**
- * @brief Mixin type used to add signal support to storage types.
- *
- * The function type of a listener is equivalent to:
- *
- * @code{.cpp}
- * void(basic_registry<entity_type> &, entity_type);
- * @endcode
- *
- * This applies to all signals made available.
- *
- * @tparam Type The type of the underlying storage.
- */
- template<typename Type>
- class sigh_storage_mixin final: public Type {
- using basic_iterator = typename Type::basic_iterator;
-
- template<typename Func>
- void notify_destruction(basic_iterator first, basic_iterator last, Func func) {
- ENTT_ASSERT(owner != nullptr, "Invalid pointer to registry");
-
- for(; first != last; ++first) {
- const auto entt = *first;
- destruction.publish(*owner, entt);
- const auto it = Type::find(entt);
- func(it, it + 1u);
- }
- }
-
- void swap_and_pop(basic_iterator first, basic_iterator last) final {
- notify_destruction(std::move(first), std::move(last), [this](auto... args) { Type::swap_and_pop(args...); });
- }
-
- void in_place_pop(basic_iterator first, basic_iterator last) final {
- notify_destruction(std::move(first), std::move(last), [this](auto... args) { Type::in_place_pop(args...); });
- }
-
- basic_iterator try_emplace(const typename Type::entity_type entt, const bool force_back, const void *value) final {
- ENTT_ASSERT(owner != nullptr, "Invalid pointer to registry");
- Type::try_emplace(entt, force_back, value);
- construction.publish(*owner, entt);
- return Type::find(entt);
- }
-
- public:
- /*! @brief Underlying entity identifier. */
- using entity_type = typename Type::entity_type;
-
- /*! @brief Inherited constructors. */
- using Type::Type;
-
- /**
- * @brief Returns a sink object.
- *
- * The sink returned by this function can be used to receive notifications
- * whenever a new instance is created and assigned to an entity.<br/>
- * Listeners are invoked after the object has been assigned to the entity.
- *
- * @sa sink
- *
- * @return A temporary sink object.
- */
- [[nodiscard]] auto on_construct() ENTT_NOEXCEPT {
- return sink{construction};
- }
-
- /**
- * @brief Returns a sink object.
- *
- * The sink returned by this function can be used to receive notifications
- * whenever an instance is explicitly updated.<br/>
- * Listeners are invoked after the object has been updated.
- *
- * @sa sink
- *
- * @return A temporary sink object.
- */
- [[nodiscard]] auto on_update() ENTT_NOEXCEPT {
- return sink{update};
- }
-
- /**
- * @brief Returns a sink object.
- *
- * The sink returned by this function can be used to receive notifications
- * whenever an instance is removed from an entity and thus destroyed.<br/>
- * Listeners are invoked before the object has been removed from the entity.
- *
- * @sa sink
- *
- * @return A temporary sink object.
- */
- [[nodiscard]] auto on_destroy() ENTT_NOEXCEPT {
- return sink{destruction};
- }
-
- /**
- * @brief Assigns entities to a storage.
- * @tparam Args Types of arguments to use to construct the object.
- * @param entt A valid identifier.
- * @param args Parameters to use to initialize the object.
- * @return A reference to the newly created object.
- */
- template<typename... Args>
- decltype(auto) emplace(const entity_type entt, Args &&...args) {
- ENTT_ASSERT(owner != nullptr, "Invalid pointer to registry");
- Type::emplace(entt, std::forward<Args>(args)...);
- construction.publish(*owner, entt);
- return this->get(entt);
- }
-
- /**
- * @brief Patches the given instance for an entity.
- * @tparam Func Types of the function objects to invoke.
- * @param entt A valid identifier.
- * @param func Valid function objects.
- * @return A reference to the patched instance.
- */
- template<typename... Func>
- decltype(auto) patch(const entity_type entt, Func &&...func) {
- ENTT_ASSERT(owner != nullptr, "Invalid pointer to registry");
- Type::patch(entt, std::forward<Func>(func)...);
- update.publish(*owner, entt);
- return this->get(entt);
- }
-
- /**
- * @brief Assigns entities to a storage.
- * @tparam It Type of input iterator.
- * @tparam Args Types of arguments to use to construct the objects assigned
- * to the entities.
- * @param first An iterator to the first element of the range of entities.
- * @param last An iterator past the last element of the range of entities.
- * @param args Parameters to use to initialize the objects assigned to the
- * entities.
- */
- template<typename It, typename... Args>
- void insert(It first, It last, Args &&...args) {
- ENTT_ASSERT(owner != nullptr, "Invalid pointer to registry");
- Type::insert(first, last, std::forward<Args>(args)...);
-
- for(auto it = construction.empty() ? last : first; it != last; ++it) {
- construction.publish(*owner, *it);
- }
- }
-
- /**
- * @brief Forwards variables to mixins, if any.
- * @param value A variable wrapped in an opaque container.
- */
- void bind(any value) ENTT_NOEXCEPT final {
- auto *reg = any_cast<basic_registry<entity_type>>(&value);
- owner = reg ? reg : owner;
- Type::bind(std::move(value));
- }
-
- private:
- sigh<void(basic_registry<entity_type> &, const entity_type)> construction{};
- sigh<void(basic_registry<entity_type> &, const entity_type)> destruction{};
- sigh<void(basic_registry<entity_type> &, const entity_type)> update{};
- basic_registry<entity_type> *owner{};
- };
-
- } // namespace entt
-
- #endif
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