doc: updated links and references to similar projects

Signed-off-by: Innokentiy Alaytsev <alaitsev@gmail.com>

docs/md/entity.md

@@ -1281,7 +1281,7 @@ thrown away. The reasons for this go far beyond the scope of this document.<br/>
 To iterate a runtime view, either use it in a range-for loop:
 
 ```cpp
-entt::component types[] = { entt::type_info<position>::id(), entt::type_info<velocity>::id() };
+entt::id_type types[] = { entt::type_info<position>::id(), entt::type_info<velocity>::id() };
 auto view = registry.runtime_view(std::cbegin(types), std::cend(types));
 
 for(auto entity: view) {
@@ -1299,7 +1299,7 @@ for(auto entity: view) {
 Or rely on the `each` member function to iterate entities:
 
 ```cpp
-entt::component types[] = { entt::type_info<position>::id(), entt::type_info<velocity>::id() };
+entt::id_type types[] = { entt::type_info<position>::id(), entt::type_info<velocity>::id() };
 
 registry.runtime_view(std::cbegin(types), std::cend(types)).each([](auto entity) {
     // ...
@@ -1310,8 +1310,8 @@ Performance are exactly the same in both cases.<br/>
 Filtering entities by components is also supported for this kind of views:
 
 ```cpp
-entt::component components[] = { entt::type_info<position>::id() };
-entt::component filter[] = { entt::type_info<velocity>::id() };
+entt::id_type components[] = { entt::type_info<position>::id() };
+entt::id_type filter[] = { entt::type_info<velocity>::id() };
 auto view = registry.runtime_view(std::cbegin(components), std::cend(components), std::cbegin(filter), std::cend(filter));
 ```
 

docs/md/links.md

@@ -117,6 +117,7 @@ I hope this list can grow much more in the future:
     - [Native Scripting](https://www.youtube.com/watch?v=iIUhg88MK5M).
     - [Native Scripting (now with virtual functions!)](https://www.youtube.com/watch?v=1cHEcrIn8IQ).
     - [Scene Hierarchy Panel](https://www.youtube.com/watch?v=wziDnE8guvI).
+    - [Properties Panel](https://www.youtube.com/watch?v=NBpB0qscF3E).
   * [Ability Creator](https://www.erichildebrand.net/blog/ability-creator-project-retrospect):
     project retrospect by [Eric Hildebrand](https://www.erichildebrand.net/).
 

docs/md/references.md

@@ -42,5 +42,8 @@ I hope this list can grow much more in the future:
   * [Specs](https://github.com/amethyst/specs): a parallel ECS based mainly on
     hierarchical bitsets that allows different types of storage as needed.
 
+* Zig
+  * [zig-ecs](https://github.com/prime31/zig-ecs): a _zig-ification_ of `EnTT`.
+
 If you know of other resources out there that can be of interest for the reader,
 feel free to open an issue or a PR and I'll be glad to add them to this page.

src/entt/config/version.h

@@ -4,7 +4,7 @@
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 5
-#define ENTT_VERSION_PATCH 1
+#define ENTT_VERSION_PATCH 2
 
 
 #endif

src/entt/entity/sparse_set.hpp

@@ -386,7 +386,7 @@ public:
      */
     void emplace(const entity_type entt) {
         ENTT_ASSERT(!contains(entt));
-        assure(page(entt))[offset(entt)] = entity_type(static_cast<typename traits_type::entity_type>(packed.size()));
+        assure(page(entt))[offset(entt)] = entity_type{static_cast<typename traits_type::entity_type>(packed.size())};
         packed.push_back(entt);
     }
 
@@ -411,7 +411,7 @@ public:
         while(first != last) {
             const auto entt = *(first++);
             ENTT_ASSERT(!contains(entt));
-            assure(page(entt))[offset(entt)] = entity_type(next++);
+            assure(page(entt))[offset(entt)] = entity_type{next++};
         }
     }
 
@@ -505,7 +505,7 @@ public:
         algo(from, to, std::move(compare), std::forward<Args>(args)...);
 
         for(size_type pos = skip, end = skip+length; pos < end; ++pos) {
-            sparse[page(packed[pos])][offset(packed[pos])] = entity_type(static_cast<typename traits_type::entity_type>(pos));
+            sparse[page(packed[pos])][offset(packed[pos])] = entity_type{static_cast<typename traits_type::entity_type>(pos)};
         }
     }
 
@@ -554,7 +554,7 @@ public:
 
             while(curr != next) {
                 apply(packed[curr], packed[next]);
-                sparse[page(packed[curr])][offset(packed[curr])] = entity_type(static_cast<typename traits_type::entity_type>(curr));
+                sparse[page(packed[curr])][offset(packed[curr])] = entity_type{static_cast<typename traits_type::entity_type>(curr)};
 
                 curr = next;
                 next = index(packed[curr]);

src/entt/meta/meta.hpp

@@ -167,10 +167,14 @@ class meta_any {
     template<typename Type>
     [[nodiscard]] static meta_any dereference_operator(meta_any &any) {
         if constexpr(is_meta_pointer_like_v<Type>) {
-            if constexpr(std::is_const_v<std::remove_reference_t<decltype(*std::declval<Type>())>>) {
-                return *any.cast<Type>();
-            } else {
+            using pointed_type = std::remove_reference_t<decltype(*std::declval<Type>())>;
+
+            if constexpr(std::is_const_v<pointed_type> && std::is_copy_constructible_v<pointed_type>) {
+                return std::as_const(*any.cast<Type>());
+            } else if constexpr(!std::is_const_v<pointed_type>) {
                 return std::ref(*any.cast<Type>());
+            } else {
+                return {};
             }
         } else {
             return {};
@@ -296,6 +300,40 @@ public:
         return storage.data();
     }
 
+    /**
+     * @brief Invokes the underlying function, if possible.
+     *
+     * @sa invoke
+     *
+     * @tparam Args Types of arguments to use to invoke the function.
+     * @param id Unique identifier.
+     * @param args Parameters to use to invoke the function.
+     * @return A meta any containing the returned value, if any.
+     */
+    template<typename... Args>
+    meta_any invoke(const id_type id, Args &&... args) const;
+
+    /**
+     * @brief Sets the value of a given variable.
+     *
+     * The type of the value must be such that a cast or conversion to the type
+     * of the variable is possible. Otherwise, invoking the setter does nothing.
+     *
+     * @tparam Type Type of value to assign.
+     * @param id Unique identifier.
+     * @param value Parameter to use to set the underlying variable.
+     * @return True in case of success, false otherwise.
+     */
+    template<typename Type>
+    bool set(const id_type id, Type &&value) const;
+
+    /**
+     * @brief Gets the value of a given variable.
+     * @param id Unique identifier.
+     * @return A meta any containing the value of the underlying variable.
+     */
+    [[nodiscard]] meta_any get(const id_type id) const;
+
     /**
      * @brief Tries to cast an instance to a given type.
      * @tparam Type Type to which to cast the instance.
@@ -916,7 +954,7 @@ struct meta_func {
      * @param sz Number of parameters to use to invoke the function.
      * @return A meta any containing the returned value, if any.
      */
-    [[nodiscard]] meta_any invoke(meta_handle instance, meta_any * const args, const std::size_t sz) const {
+    meta_any invoke(meta_handle instance, meta_any * const args, const std::size_t sz) const {
         return sz == size() ? node->invoke(instance, args) : meta_any{};
     }
 
@@ -1305,6 +1343,80 @@ public:
         return construct(arguments.data(), sizeof...(Args));
     }
 
+    /**
+     * @brief Invokes the function with the given identifier, if possible.
+     *
+     * To invoke a meta function, the parameters must be such that a cast or
+     * conversion to the required types is possible. Otherwise, an empty and
+     * thus invalid wrapper is returned.<br/>
+     * It must be possible to cast the instance to the parent type of the meta
+     * function. Otherwise, invoking the underlying function results in an
+     * undefined behavior.
+     *
+     * @param id Unique identifier.
+     * @param instance An opaque instance of the underlying type.
+     * @param args Parameters to use to invoke the function.
+     * @param sz Number of parameters to use to invoke the function.
+     * @return A meta any containing the returned value, if any.
+     */
+    meta_any invoke(const id_type id, meta_handle instance, meta_any * const args, const std::size_t sz) const {
+        auto const candidate = func(id);
+        return candidate ? candidate.invoke(std::move(instance), args, sz) : meta_any{};
+    }
+
+    /**
+     * @copybrief invoke
+     *
+     * @sa invoke
+     *
+     * @param id Unique identifier.
+     * @tparam Args Types of arguments to use to invoke the function.
+     * @param instance An opaque instance of the underlying type.
+     * @param args Parameters to use to invoke the function.
+     * @return A meta any containing the new instance, if any.
+     */
+    template<typename... Args>
+    meta_any invoke(const id_type id, meta_handle instance, Args &&... args) const {
+        std::array<meta_any, sizeof...(Args)> arguments{std::forward<Args>(args)...};
+        return invoke(id, std::move(instance), arguments.data(), sizeof...(Args));
+    }
+
+    /**
+     * @brief Sets the value of a given variable.
+     *
+     * It must be possible to cast the instance to the parent type of the meta
+     * data. Otherwise, invoking the setter results in an undefined
+     * behavior.<br/>
+     * The type of the value must be such that a cast or conversion to the type
+     * of the variable is possible. Otherwise, invoking the setter does nothing.
+     *
+     * @tparam Type Type of value to assign.
+     * @param id Unique identifier.
+     * @param instance An opaque instance of the underlying type.
+     * @param value Parameter to use to set the underlying variable.
+     * @return True in case of success, false otherwise.
+     */
+    template<typename Type>
+    bool set(const id_type id, meta_handle instance, Type &&value) const {
+        auto const candidate = data(id);
+        return candidate ? candidate.set(std::move(instance), std::forward<Type>(value)) : false;
+    }
+
+    /**
+     * @brief Gets the value of a given variable.
+     *
+     * It must be possible to cast the instance to the parent type of the meta
+     * data. Otherwise, invoking the getter results in an undefined behavior.
+     *
+     * @param id Unique identifier.
+     * @param instance An opaque instance of the underlying type.
+     * @return A meta any containing the value of the underlying variable.
+     */
+    [[nodiscard]] meta_any get(const id_type id, meta_handle instance) const {
+        auto const candidate = data(id);
+        return candidate ? candidate.get(std::move(instance)) : meta_any{};
+    }
+
     /**
      * @brief Returns a range to use to visit top-level meta properties.
      * @return An iterable range to use to visit top-level meta properties.
@@ -1352,7 +1464,7 @@ public:
      * functions and properties, as well as its constructors, destructors and
      * conversion functions if any.<br/>
      * Base classes aren't reset but the link between the two types is removed.
-     * 
+     *
      * The meta type is also removed from the list of searchable types.
      */
     void reset() ENTT_NOEXCEPT {
@@ -1376,14 +1488,14 @@ public:
                 }
             }
         };
-        
+
         unregister_all(&node->prop);
         unregister_all(&node->base);
         unregister_all(&node->conv);
         unregister_all(&node->ctor, &internal::meta_ctor_node::prop);
         unregister_all(&node->data, &internal::meta_data_node::prop);
         unregister_all(&node->func, &internal::meta_func_node::prop);
-        
+
         node->id = {};
         node->dtor = nullptr;
     }
@@ -1409,6 +1521,23 @@ private:
 }
 
 
+template<typename... Args>
+meta_any meta_any::invoke(const id_type id, Args &&... args) const {
+    return type().invoke(id, *this, std::forward<Args>(args)...);
+}
+
+
+template<typename Type>
+bool meta_any::set(const id_type id, Type &&value) const {
+    return type().set(id, *this, std::forward<Type>(value));
+}
+
+
+[[nodiscard]] inline meta_any meta_any::get(const id_type id) const {
+    return type().get(id, *this);
+}
+
+
 [[nodiscard]] inline meta_type meta_base::parent() const ENTT_NOEXCEPT {
     return node->parent;
 }

test/entt/meta/meta_any.cpp

@@ -5,6 +5,14 @@
 #include <entt/meta/meta.hpp>
 #include <entt/meta/resolve.hpp>
 
+struct clazz_t {
+    void member(int i) { value = i; }
+    static void func() { c = 'd'; }
+
+	static inline char c = 'c';
+    int value = 0;
+};
+
 struct empty_t {
     virtual ~empty_t() = default;
     static void destroy(empty_t &) {
@@ -46,6 +54,12 @@ struct MetaAny: ::testing::Test {
         entt::meta<double>().conv<int>();
         entt::meta<empty_t>().dtor<&empty_t::destroy>();
         entt::meta<fat_t>().base<empty_t>().dtor<&fat_t::destroy>();
+
+        entt::meta<clazz_t>()
+            .type("clazz"_hs)
+            .data<&clazz_t::value>("value"_hs)
+            .func<&clazz_t::member>("member"_hs)
+            .func<&clazz_t::func>("func"_hs);
     }
 
     void SetUp() override {
@@ -622,3 +636,32 @@ TEST_F(MetaAny, UnmanageableType) {
     ASSERT_TRUE(std::as_const(any).convert<unmanageable_t>());
     ASSERT_FALSE(std::as_const(any).convert<int>());
 }
+
+TEST_F(MetaAny, Invoke) {
+    clazz_t instance;
+    entt::meta_any any{std::ref(instance)};
+
+	ASSERT_TRUE(any.invoke("func"_hs));
+	ASSERT_TRUE(any.invoke("member"_hs, 42));
+	ASSERT_FALSE(any.invoke("non_existent"_hs, 42));
+
+	ASSERT_EQ(clazz_t::c, 'd');
+	ASSERT_EQ(instance.value, 42);
+}
+
+TEST_F(MetaAny, SetGet) {
+    clazz_t instance;
+    entt::meta_any any{std::ref(instance)};
+
+	ASSERT_TRUE(any.set("value"_hs, 42));
+
+    const auto value = any.get("value"_hs);
+
+	ASSERT_TRUE(value);
+	ASSERT_TRUE(value.try_cast<int>());
+	ASSERT_EQ(value.cast<int>(), 42);
+    ASSERT_EQ(instance.value, 42);
+
+	ASSERT_FALSE(any.set("non_existent"_hs, 42));
+	ASSERT_FALSE(any.get("non_existent"_hs));
+}

test/entt/meta/meta_pointer.cpp

@@ -4,6 +4,14 @@
 #include <entt/meta/pointer.hpp>
 #include <entt/meta/resolve.hpp>
 
+struct not_copyable_t {
+    not_copyable_t() = default;
+    not_copyable_t(const not_copyable_t &) = delete;
+    not_copyable_t(not_copyable_t &&) = default;
+    not_copyable_t & operator=(const not_copyable_t &) = delete;
+    not_copyable_t & operator=(not_copyable_t &&) = default;
+};
+
 TEST(MetaPointerLike, DereferenceOperatorInvalidType) {
     int value = 0;
     entt::meta_any any{value};
@@ -79,3 +87,11 @@ TEST(MetaPointerLike, DereferenceOperatorSmartPointer) {
     ASSERT_EQ(*any.cast<std::shared_ptr<int>>(), 42);
     ASSERT_EQ(*value, 42);
 }
+
+TEST(MetaPointerLike, PointerToMoveOnlyType) {
+    const not_copyable_t instance;
+    entt::meta_any any{&instance};
+
+    ASSERT_TRUE(any);
+    ASSERT_FALSE(*any);
+}

test/entt/meta/meta_type.cpp

@@ -272,6 +272,27 @@ TEST_F(MetaType, Func) {
     ASSERT_TRUE(type.func("func"_hs).invoke({}));
 }
 
+TEST_F(MetaType, Invoke) {
+    auto type = entt::resolve<clazz_t>();
+    clazz_t instance{};
+
+    ASSERT_TRUE(type.invoke("member"_hs, instance));
+    ASSERT_FALSE(type.invoke("rebmem"_hs, {}));
+}
+
+TEST_F(MetaType, SetGet) {
+    auto type = entt::resolve<clazz_t>();
+    clazz_t instance{};
+
+    ASSERT_TRUE(type.set("value"_hs, instance, 42));
+    ASSERT_FALSE(type.set("eulav"_hs, instance, 3));
+    ASSERT_EQ(instance.value, 42);
+
+    ASSERT_FALSE(type.get("eulav"_hs, instance));
+    ASSERT_TRUE(type.get("value"_hs, instance));
+    ASSERT_EQ(type.get("value"_hs, instance).cast<int>(), 42);
+}
+
 TEST_F(MetaType, Construct) {
     auto any = entt::resolve<clazz_t>().construct(base_t{}, 42);