Fix play mode runtime scene replacement

editor/src/Core/PlaySessionController.cpp

@@ -72,6 +72,7 @@ void PlaySessionController::Attach(IEditorContext& context) {
 
 void PlaySessionController::Detach(IEditorContext& context) {
     StopPlay(context);
+    ClearRuntimeSceneSyncSubscription(context);
 
     if (m_playStartRequestedHandlerId != 0) {
         context.GetEventBus().Unsubscribe<PlayModeStartRequestedEvent>(m_playStartRequestedHandlerId);
@@ -141,6 +142,7 @@ bool PlaySessionController::StartPlay(IEditorContext& context) {
     XCEngine::Input::InputManager::Get().Shutdown();
     XCEngine::Input::InputManager::Get().Initialize(nullptr);
     m_runtimeLoop.Start(sceneManager.GetScene());
+    EnsureRuntimeSceneSyncSubscription(context);
     context.GetUndoManager().ClearHistory();
     context.SetRuntimeMode(EditorRuntimeMode::Play);
     context.GetEventBus().Publish(PlayModeStartedEvent{});
@@ -152,6 +154,7 @@ bool PlaySessionController::StopPlay(IEditorContext& context) {
         return false;
     }
 
+    ClearRuntimeSceneSyncSubscription(context);
     auto& sceneManager = context.GetSceneManager();
     m_runtimeLoop.Stop();
     ResetRuntimeInputBridge();
@@ -206,6 +209,39 @@ void PlaySessionController::ResetRuntimeInputBridge() {
     m_hasPendingGameViewInput = false;
 }
 
+void PlaySessionController::EnsureRuntimeSceneSyncSubscription(IEditorContext& context) {
+    if (m_runtimeSceneChangedHandlerId != 0) {
+        return;
+    }
+
+    m_runtimeSceneChangedHandlerId = context.GetEventBus().Subscribe<SceneChangedEvent>(
+        [this, &context](const SceneChangedEvent&) {
+            SyncRuntimeSceneIfNeeded(context);
+        });
+}
+
+void PlaySessionController::ClearRuntimeSceneSyncSubscription(IEditorContext& context) {
+    if (m_runtimeSceneChangedHandlerId == 0) {
+        return;
+    }
+
+    context.GetEventBus().Unsubscribe<SceneChangedEvent>(m_runtimeSceneChangedHandlerId);
+    m_runtimeSceneChangedHandlerId = 0;
+}
+
+void PlaySessionController::SyncRuntimeSceneIfNeeded(IEditorContext& context) {
+    if (!IsEditorRuntimeActive(context.GetRuntimeMode())) {
+        return;
+    }
+
+    auto* currentScene = context.GetSceneManager().GetScene();
+    if (currentScene == m_runtimeLoop.GetScene()) {
+        return;
+    }
+
+    m_runtimeLoop.ReplaceScene(currentScene);
+}
+
 void PlaySessionController::ApplyGameViewInputFrame(float deltaTime) {
     using XCEngine::Input::InputManager;
     using XCEngine::Input::KeyCode;

editor/src/Core/PlaySessionController.h

@@ -28,9 +28,14 @@ public:
     bool ResumePlay(IEditorContext& context);
     bool StepPlay(IEditorContext& context);
 
+    ::XCEngine::Components::Scene* GetRuntimeScene() const { return m_runtimeLoop.GetScene(); }
+
 private:
     void ResetRuntimeInputBridge();
     void ApplyGameViewInputFrame(float deltaTime);
+    void EnsureRuntimeSceneSyncSubscription(IEditorContext& context);
+    void ClearRuntimeSceneSyncSubscription(IEditorContext& context);
+    void SyncRuntimeSceneIfNeeded(IEditorContext& context);
 
     uint64_t m_playStartRequestedHandlerId = 0;
     uint64_t m_playStopRequestedHandlerId = 0;
@@ -38,6 +43,7 @@ private:
     uint64_t m_playResumeRequestedHandlerId = 0;
     uint64_t m_playStepRequestedHandlerId = 0;
     uint64_t m_gameViewInputFrameHandlerId = 0;
+    uint64_t m_runtimeSceneChangedHandlerId = 0;
     SceneSnapshot m_editorSnapshot = {};
     GameViewInputFrameEvent m_pendingGameViewInput = {};
     GameViewInputFrameEvent m_appliedGameViewInput = {};