Rework GDCLASS macro to allow pure virtual functions

godotengine · Jan 12, 2024 · 16be4f8 · 16be4f8
1 parent 0ddef6e
commit 16be4f8
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Showing 2 changed files with 25 additions and 13 deletions.
diff --git a/include/godot_cpp/classes/wrapped.hpp b/include/godot_cpp/classes/wrapped.hpp
@@ -42,13 +42,17 @@
 namespace godot {
 
 class ClassDB;
+template <class T>
+class ClassCreator;
 
 typedef void GodotObject;
 
 // Base for all engine classes, to contain the pointer to the engine instance.
 class Wrapped {
 	friend class GDExtensionBinding;
 	friend void postinitialize_handler(Wrapped *);
+	template <class T>
+	friend class ClassCreator;
 
 protected:
 #ifdef HOT_RELOAD_ENABLED
@@ -132,16 +136,33 @@ struct EngineClassRegistration {
 } // namespace godot
 
 #ifdef HOT_RELOAD_ENABLED
-#define _GDCLASS_RECREATE(m_class, m_inherits)                                                   \
+#define _GDCLASS_RECREATE(m_class)                                                               \
 	m_class *new_instance = (m_class *)memalloc(sizeof(m_class));                                \
 	Wrapped::RecreateInstance recreate_data = { new_instance, obj, Wrapped::recreate_instance }; \
 	Wrapped::recreate_instance = &recreate_data;                                                 \
 	memnew_placement(new_instance, m_class);                                                     \
 	return new_instance;
 #else
-#define _GDCLASS_RECREATE(m_class, m_inherits) return nullptr;
+#define _GDCLASS_RECREATE(m_class) return nullptr;
 #endif
 
+namespace godot {
+
+template <class T>
+class ClassCreator {
+public:
+	static GDExtensionObjectPtr create(void *data) {
+		T *new_object = memnew(T);
+		return new_object->_owner;
+	};
+
+	static GDExtensionClassInstancePtr recreate(void *data, GDExtensionObjectPtr obj) {
+		_GDCLASS_RECREATE(T)
+	}
+};
+
+} // namespace godot
+
 // Use this on top of your own classes.
 // Note: the trail of `***` is to keep sane diffs in PRs, because clang-format otherwise moves every `\` which makes
 // every line of the macro different
@@ -226,15 +247,6 @@ public:
 		return m_inherits::get_class_static();                                                                                                                                         \
 	}                                                                                                                                                                                  \
                                                                                                                                                                                        \
-	static GDExtensionObjectPtr create(void *data) {                                                                                                                                   \
-		m_class *new_object = memnew(m_class);                                                                                                                                         \
-		return new_object->_owner;                                                                                                                                                     \
-	}                                                                                                                                                                                  \
-                                                                                                                                                                                       \
-	static GDExtensionClassInstancePtr recreate(void *data, GDExtensionObjectPtr obj) {                                                                                                \
-		_GDCLASS_RECREATE(m_class, m_inherits);                                                                                                                                        \
-	}                                                                                                                                                                                  \
-                                                                                                                                                                                       \
 	static void notification_bind(GDExtensionClassInstancePtr p_instance, int32_t p_what, GDExtensionBool p_reversed) {                                                                \
 		if (p_instance && m_class::_get_notification()) {                                                                                                                              \
 			if (m_class::_get_notification() != m_inherits::_get_notification()) {                                                                                                     \

diff --git a/include/godot_cpp/core/class_db.hpp b/include/godot_cpp/core/class_db.hpp
@@ -202,9 +202,9 @@ void ClassDB::_register_class(bool p_virtual, bool p_exposed) {
 		T::to_string_bind, // GDExtensionClassToString to_string_func;
 		nullptr, // GDExtensionClassReference reference_func;
 		nullptr, // GDExtensionClassUnreference unreference_func;
-		T::create, // GDExtensionClassCreateInstance create_instance_func; /* this one is mandatory */
+		ClassCreator<T>::create, // GDExtensionClassCreateInstance create_instance_func; /* this one is mandatory */
 		T::free, // GDExtensionClassFreeInstance free_instance_func; /* this one is mandatory */
-		T::recreate, // GDExtensionClassRecreateInstance recreate_instance_func;
+		ClassCreator<T>::recreate, // GDExtensionClassRecreateInstance recreate_instance_func;
 		&ClassDB::get_virtual_func, // GDExtensionClassGetVirtual get_virtual_func;
 		nullptr, // GDExtensionClassGetVirtualCallData get_virtual_call_data_func;
 		nullptr, // GDExtensionClassCallVirtualWithData call_virtual_func;