Expose prefab instantiation to Lua

Resources/Engine/Lua/Resources/Prefab.lua

@@ -0,0 +1,7 @@
+---@meta
+
+--- Represents a Prefab asset reference
+---@class Prefab
+---@field path string
+---@overload fun(): Prefab
+Prefab = {}

Resources/Engine/Lua/Scene/Scene.lua

@@ -30,3 +30,9 @@ function Scene:FindActorsByTag(tag) end
 ---@overload fun(self: Scene, name: string, tag: string): Actor
 ---@return Actor
 function Scene:CreateActor(...) end
+
+--- Instantiates a prefab in the scene
+---@overload fun(self: Scene, prefab: Prefab): Actor|nil
+---@overload fun(self: Scene, prefab: Prefab, parent: Actor): Actor|nil
+---@return Actor|nil
+function Scene:InstantiatePrefab(...) end

Sources/OvCore/include/OvCore/ECS/Actor.inl

@@ -20,7 +20,7 @@ namespace OvCore::ECS
 			m_components.push_back(std::make_shared<T>(*this, p_args...));
 			T& instance = *dynamic_cast<T*>(m_components.back().get());
 			ComponentAddedEvent.Invoke(instance);
-			if (m_playing && IsActive())
+			if (m_playing && !m_sleeping && IsActive())
 			{
 				reinterpret_cast<OvCore::ECS::Components::AComponent&>(instance).OnAwake();
 				reinterpret_cast<OvCore::ECS::Components::AComponent&>(instance).OnEnable();
@@ -74,4 +74,4 @@ namespace OvCore::ECS
 
 		return nullptr;
 	}
-}
+}

Sources/OvCore/include/OvCore/SceneSystem/PrefabOperations.h

@@ -8,6 +8,7 @@
 
 #include <filesystem>
 #include <functional>
+#include <string>
 
 namespace OvCore::ECS
 {
@@ -34,6 +35,16 @@ namespace OvCore::SceneSystem
 		*/
 		static bool SaveToFile(OvCore::ECS::Actor& p_rootActor, const std::filesystem::path& p_outputPath);
 
+		/**
+		* Set the root prefab source and remove redundant inherited sources from children.
+		* @param p_rootActor
+		* @param p_newRootPrefabSource
+		*/
+		static void SetRootPrefabSourceAndNormalizeChildren(
+			OvCore::ECS::Actor& p_rootActor,
+			const std::string& p_newRootPrefabSource
+		);
+
 		/**
 		* Instantiate a prefab file using the provided actor factory.
 		* @param p_prefabPath

Sources/OvCore/include/OvCore/SceneSystem/Scene.h

@@ -6,6 +6,10 @@
 
 #pragma once
 
+#include <filesystem>
+#include <functional>
+#include <string>
+#include <vector>
 
 #include <OvCore/API/ISerializable.h>
 #include <OvCore/ECS/Actor.h>
@@ -14,6 +18,7 @@
 #include <OvCore/ECS/Components/CModelRenderer.h>
 #include <OvCore/ECS/Components/CPostProcessStack.h>
 #include <OvCore/ECS/Components/CReflectionProbe.h>
+#include <OvTools/Utils/OptRef.h>
 
 namespace OvCore::SceneSystem
 {
@@ -39,7 +44,10 @@ namespace OvCore::SceneSystem
 		/**
 		* Constructor of the scene
 		*/
-		Scene();
+		Scene(
+			const std::filesystem::path& p_projectAssetsPath = "",
+			const std::filesystem::path& p_engineAssetsPath = ""
+		);
 
 		/**
 		* Handle the memory de-allocation of every actors
@@ -116,6 +124,19 @@ namespace OvCore::SceneSystem
 		*/
 		ECS::Actor& CreateActor(const std::string& p_name, const std::string& p_tag = "");
 
+		/**
+		* Instantiate a prefab and return its root actor.
+		* @param p_prefabPath
+		*/
+		ECS::Actor* InstantiatePrefab(const std::string& p_prefabPath);
+
+		/**
+		* Instantiate a prefab under the given parent and return its root actor.
+		* @param p_prefabPath
+		* @param p_parent
+		*/
+		ECS::Actor* InstantiatePrefab(const std::string& p_prefabPath, ECS::Actor& p_parent);
+
 		/**
 		* Destroy and actor and return true on success
 		* @param p_target (The actor to remove from the scene)
@@ -205,10 +226,19 @@ namespace OvCore::SceneSystem
 		virtual void OnDeserialize(tinyxml2::XMLDocument& p_doc, tinyxml2::XMLNode* p_root) override;
 
 	private:
+		std::filesystem::path GetRealAssetPath(const std::string& p_path) const;
+		void BeginBatchActorCreation();
+		void EndBatchActorCreation(bool p_startCreatedActors);
+		ECS::Actor* InstantiatePrefabInternal(const std::string& p_prefabPath, OvTools::Utils::OptRef<ECS::Actor> p_parent);
+
 		int64_t m_availableID = 1;
 		bool m_isPlaying = false;
+		bool m_batchActorCreation = false;
 		std::vector<ECS::Actor*> m_actors;
+		std::vector<std::reference_wrapper<ECS::Actor>> m_batchCreatedActors;
 
 		FastAccessComponents m_fastAccessComponents;
+		std::filesystem::path m_projectAssetsPath;
+		std::filesystem::path m_engineAssetsPath;
 	};
-}
+}

Sources/OvCore/include/OvCore/SceneSystem/SceneManager.h

@@ -6,7 +6,9 @@
 
 #pragma once
 
-
+#include <functional>
+#include <memory>
+#include <string>
 
 #include "OvCore/SceneSystem/Scene.h"
 
@@ -19,11 +21,15 @@ namespace OvCore::SceneSystem
 	{
 	public:
 
-		/** 
+		/**
 		* Default constructor
 		* @param p_sceneRootFolder (Optional)
+		* @param p_engineAssetsFolder (Optional)
 		*/
-		SceneManager(const std::string& p_sceneRootFolder = "");
+		SceneManager(
+			const std::string& p_sceneRootFolder = "",
+			const std::string& p_engineAssetsFolder = ""
+		);
 
 		/**
 		* Default destructor
@@ -108,11 +114,12 @@ namespace OvCore::SceneSystem
 
 	private:
 		const std::string m_sceneRootFolder;
+		const std::string m_engineAssetsFolder;
 		std::unique_ptr<Scene> m_currentScene = nullptr;
 
 		bool m_currentSceneLoadedFromPath = false;
 		std::string m_currentSceneSourcePath = "";
 
 		std::function<void()> m_delayedLoadCall;
 	};
-}
+}

Sources/OvCore/src/OvCore/ECS/Actor.cpp

@@ -410,7 +410,7 @@ OvCore::ECS::Components::Behaviour & OvCore::ECS::Actor::AddBehaviour(const std:
 	m_behavioursOrder.push_back(p_name);
 	Components::Behaviour& newInstance = m_behaviours.at(p_name);
 	BehaviourAddedEvent.Invoke(newInstance);
-	if (m_playing && IsActive())
+	if (m_playing && !m_sleeping && IsActive())
 	{
 		newInstance.OnAwake();
 		newInstance.OnEnable();
@@ -475,7 +475,7 @@ bool OvCore::ECS::Actor::RenameBehaviour(const std::string& p_previousName, cons
 	m_behaviours.try_emplace(p_newName, *this, p_newName);
 	Components::Behaviour& newInstance = m_behaviours.at(p_newName);
 	BehaviourAddedEvent.Invoke(newInstance);
-	if (m_playing && IsActive())
+	if (m_playing && !m_sleeping && IsActive())
 	{
 		newInstance.OnAwake();
 		newInstance.OnEnable();

Sources/OvCore/src/OvCore/SceneSystem/PrefabOperations.cpp

@@ -17,6 +17,28 @@
 
 namespace
 {
+	void NormalizePrefabSourcesRecursively(
+		OvCore::ECS::Actor& p_actor,
+		const std::string& p_inheritedPrefabSource)
+	{
+		if (p_actor.HasPrefabSource())
+		{
+			const std::string currentPrefabSource = p_actor.GetPrefabSource();
+			if (currentPrefabSource == p_inheritedPrefabSource)
+			{
+				p_actor.SetPrefabSource("?");
+			}
+		}
+
+		const std::string nextInheritedPrefabSource =
+			p_actor.HasPrefabSource() ? p_actor.GetPrefabSource() : p_inheritedPrefabSource;
+
+		for (auto* child : p_actor.GetChildren())
+		{
+			NormalizePrefabSourcesRecursively(*child, nextInheritedPrefabSource);
+		}
+	}
+
 	void SerializeActorHierarchy(
 		OvCore::ECS::Actor& p_actor,
 		tinyxml2::XMLDocument& p_doc,
@@ -54,6 +76,18 @@ bool OvCore::SceneSystem::PrefabOperations::SaveToFile(OvCore::ECS::Actor& p_roo
 	return doc.SaveFile(p_outputPath.string().c_str()) == tinyxml2::XML_SUCCESS;
 }
 
+void OvCore::SceneSystem::PrefabOperations::SetRootPrefabSourceAndNormalizeChildren(
+	OvCore::ECS::Actor& p_rootActor,
+	const std::string& p_newRootPrefabSource)
+{
+	p_rootActor.SetPrefabSource(p_newRootPrefabSource);
+
+	for (auto* child : p_rootActor.GetChildren())
+	{
+		NormalizePrefabSourcesRecursively(*child, p_newRootPrefabSource);
+	}
+}
+
 OvCore::ECS::Actor* OvCore::SceneSystem::PrefabOperations::InstantiateFromFile(
 	const std::filesystem::path& p_prefabPath,
 	const std::function<OvCore::ECS::Actor&(void)>& p_createActor)