FullscreenUI: Support renderer swapping without restart

src/core/fullscreen_ui.cpp

@@ -592,23 +592,21 @@ bool FullscreenUI::Initialize()
       !LoadResources())
   {
     DestroyResources();
-    ImGuiFullscreen::Shutdown();
+    Shutdown(true);
     s_state.tried_to_initialize = true;
     return false;
   }
 
   s_state.initialized = true;
-  s_state.current_main_window = MainWindowType::None;
-  s_state.current_pause_submenu = PauseSubMenu::None;
-  s_state.pause_menu_was_open = false;
-  s_state.was_paused_on_quick_menu_open = false;
-  s_state.about_window_open = false;
   s_state.hotkey_list_cache = InputManager::GetHotkeyList();
 
   Host::RunOnCPUThread([]() { Host::OnFullscreenUIStartedOrStopped(true); });
 
-  if (!GPUThread::HasGPUBackend() && !GPUThread::IsGPUBackendRequested())
+  if (s_state.current_main_window == MainWindowType::None && !GPUThread::HasGPUBackend() &&
+      !GPUThread::IsGPUBackendRequested())
+  {
     SwitchToLanding();
+  }
 
   UpdateRunIdleState();
   ForceKeyNavEnabled();
@@ -799,8 +797,16 @@ void FullscreenUI::OpenPauseSubMenu(PauseSubMenu submenu)
   QueueResetFocus(FocusResetType::ViewChanged);
 }
 
-void FullscreenUI::Shutdown()
+void FullscreenUI::Shutdown(bool clear_state)
 {
+  if (clear_state)
+  {
+    s_state.current_main_window = MainWindowType::None;
+    s_state.current_pause_submenu = PauseSubMenu::None;
+    s_state.pause_menu_was_open = false;
+    s_state.was_paused_on_quick_menu_open = false;
+    s_state.about_window_open = false;
+
     Achievements::ClearUIState();
     ClearInputBindingVariables();
     CloseSaveStateSelector();
@@ -818,8 +824,10 @@ void FullscreenUI::Shutdown()
     s_state.graphics_adapter_list_cache = {};
     s_state.hotkey_list_cache = {};
     s_state.current_game_subtitle = {};
+  }
+
   DestroyResources();
-  ImGuiFullscreen::Shutdown();
+  ImGuiFullscreen::Shutdown(clear_state);
   if (s_state.initialized)
     Host::RunOnCPUThread([]() { Host::OnFullscreenUIStartedOrStopped(false); });
 
@@ -4318,7 +4326,6 @@ void FullscreenUI::DrawGraphicsSettingsPage()
       else
         bsi->SetStringValue("GPU", "Adapter", value);
       SetSettingsChanged(bsi);
-      ShowToast(std::string(), FSUI_STR("GPU adapter will be applied after restarting."), 10.0f);
       CloseChoiceDialog();
     };
     OpenChoiceDialog(FSUI_ICONSTR(ICON_FA_MICROCHIP, "GPU Adapter"), false, std::move(options), std::move(callback));

src/core/fullscreen_ui.h

@@ -35,7 +35,7 @@ void ReturnToPreviousWindow();
 void SetStandardSelectionFooterText(bool back_instead_of_cancel);
 #endif
 
-void Shutdown();
+void Shutdown(bool clear_state);
 void Render();
 void InvalidateCoverCache();
 void TimeToPrintableString(SmallStringBase* str, time_t t);

src/core/gpu_thread.cpp

@@ -68,8 +68,8 @@ static bool IsCommandFIFOEmpty();
 static void WakeGPUThread();
 static bool SleepGPUThread(bool allow_sleep);
 
-static bool CreateDeviceOnThread(RenderAPI api, bool fullscreen, Error* error);
-static void DestroyDeviceOnThread();
+static bool CreateDeviceOnThread(RenderAPI api, bool fullscreen, bool clear_fsui_state_on_failure, Error* error);
+static void DestroyDeviceOnThread(bool clear_fsui_state);
 static void ResizeDisplayWindowOnThread(u32 width, u32 height, float scale);
 static void UpdateDisplayWindowOnThread(bool fullscreen);
 static void DisplayWindowResizedOnThread();
@@ -610,7 +610,7 @@ bool GPUThread::IsGPUBackendRequested()
   return s_state.requested_renderer.has_value();
 }
 
-bool GPUThread::CreateDeviceOnThread(RenderAPI api, bool fullscreen, Error* error)
+bool GPUThread::CreateDeviceOnThread(RenderAPI api, bool fullscreen, bool clear_fsui_state_on_failure, Error* error)
 {
   DebugAssert(!g_gpu_device);
 
@@ -686,7 +686,7 @@ bool GPUThread::CreateDeviceOnThread(RenderAPI api, bool fullscreen, Error* erro
   {
     ERROR_LOG("Failed to initialize ImGuiManager: {}", create_error.GetDescription());
     Error::SetStringFmt(error, "Failed to initialize ImGuiManager: {}", create_error.GetDescription());
-    FullscreenUI::Shutdown();
+    FullscreenUI::Shutdown(clear_fsui_state_on_failure);
     ImGuiManager::Shutdown();
     g_gpu_device->Destroy();
     g_gpu_device.reset();
@@ -707,14 +707,14 @@ bool GPUThread::CreateDeviceOnThread(RenderAPI api, bool fullscreen, Error* erro
   return true;
 }
 
-void GPUThread::DestroyDeviceOnThread()
+void GPUThread::DestroyDeviceOnThread(bool clear_fsui_state)
 {
   if (!g_gpu_device)
     return;
 
   const bool has_window = g_gpu_device->HasMainSwapChain();
 
-  FullscreenUI::Shutdown();
+  FullscreenUI::Shutdown(clear_fsui_state);
   ImGuiManager::Shutdown();
 
   INFO_LOG("Destroying {} GPU device...", GPUDevice::RenderAPIToString(g_gpu_device->GetRenderAPI()));
@@ -749,12 +749,12 @@ void GPUThread::HandleGPUDeviceLost()
   // Device lost, something went really bad.
   // Let's just toss out everything, and try to hobble on.
   DestroyGPUBackendOnThread();
-  DestroyDeviceOnThread();
+  DestroyDeviceOnThread(false);
 
   Error error;
   if (!CreateDeviceOnThread(
         Settings::GetRenderAPIForRenderer(s_state.requested_renderer.value_or(g_gpu_settings.gpu_renderer)),
-        is_fullscreen, &error) ||
+        is_fullscreen, true, &error) ||
       (s_state.requested_renderer.has_value() &&
        !CreateGPUBackendOnThread(s_state.requested_renderer.value(), true, &error)))
   {
@@ -832,7 +832,7 @@ void GPUThread::ReconfigureOnThread(GPUThreadReconfigureCommand* cmd)
   if (!cmd->renderer.has_value() && !s_state.requested_fullscreen_ui)
   {
     DestroyGPUBackendOnThread();
-    DestroyDeviceOnThread();
+    DestroyDeviceOnThread(true);
     return;
   }
 
@@ -864,10 +864,10 @@ void GPUThread::ReconfigureOnThread(GPUThreadReconfigureCommand* cmd)
   if (cmd->force_recreate_device || !GPUDevice::IsSameRenderAPI(current_api, expected_api))
   {
     const bool fullscreen = cmd->fullscreen.value_or(Host::IsFullscreen());
-    DestroyDeviceOnThread();
+    DestroyDeviceOnThread(false);
 
     Error local_error;
-    if (!CreateDeviceOnThread(expected_api, fullscreen, &local_error))
+    if (!CreateDeviceOnThread(expected_api, fullscreen, false, &local_error))
     {
       Host::AddIconOSDMessage(
         "DeviceSwitchFailed", ICON_FA_PAINT_ROLLER,
@@ -877,7 +877,7 @@ void GPUThread::ReconfigureOnThread(GPUThreadReconfigureCommand* cmd)
         Host::OSD_CRITICAL_ERROR_DURATION);
 
       Host::ReleaseRenderWindow();
-      if (current_api == RenderAPI::None || !CreateDeviceOnThread(current_api, fullscreen, &local_error))
+      if (current_api == RenderAPI::None || !CreateDeviceOnThread(current_api, fullscreen, true, &local_error))
       {
         if (cmd->error_ptr)
           *cmd->error_ptr = local_error;
@@ -895,7 +895,8 @@ void GPUThread::ReconfigureOnThread(GPUThreadReconfigureCommand* cmd)
   }
   else if (s_state.requested_fullscreen_ui)
   {
-    if (!g_gpu_device && !CreateDeviceOnThread(expected_api, cmd->fullscreen.value_or(false), cmd->error_ptr))
+    const bool had_gpu_device = static_cast<bool>(g_gpu_device);
+    if (!g_gpu_device && !CreateDeviceOnThread(expected_api, cmd->fullscreen.value_or(false), true, cmd->error_ptr))
     {
       *cmd->out_result = false;
       return;
@@ -905,12 +906,16 @@ void GPUThread::ReconfigureOnThread(GPUThreadReconfigureCommand* cmd)
     g_gpu_device->SetGPUTimingEnabled(false);
 
     if (!(*cmd->out_result = FullscreenUI::IsInitialized() || FullscreenUI::Initialize()))
+    {
       Error::SetStringView(cmd->error_ptr, "Failed to initialize FullscreenUI.");
+      if (!had_gpu_device)
+        DestroyDeviceOnThread(true);
+    }
   }
   else
   {
     // Device is no longer needed.
-    DestroyDeviceOnThread();
+    DestroyDeviceOnThread(true);
   }
 }
 

src/core/settings.cpp

@@ -1093,7 +1093,7 @@ void Settings::FixIncompatibleSettings(const SettingsInterface& si, bool display
 
 bool Settings::AreGPUDeviceSettingsChanged(const Settings& old_settings) const
 {
-  return (gpu_use_debug_device != old_settings.gpu_use_debug_device ||
+  return (gpu_adapter != old_settings.gpu_adapter || gpu_use_debug_device != old_settings.gpu_use_debug_device ||
           gpu_disable_shader_cache != old_settings.gpu_disable_shader_cache ||
           gpu_disable_dual_source_blend != old_settings.gpu_disable_dual_source_blend ||
           gpu_disable_framebuffer_fetch != old_settings.gpu_disable_framebuffer_fetch ||

src/core/system.cpp

@@ -4577,7 +4577,7 @@ void System::CheckForSettingsChanges(const Settings& old_settings)
     if (GPUThread::IsFullscreenUIRequested())
     {
       // handle device setting updates as well
-      if (g_settings.AreGPUDeviceSettingsChanged(old_settings))
+      if (g_settings.gpu_renderer != old_settings.gpu_renderer || g_settings.AreGPUDeviceSettingsChanged(old_settings))
         GPUThread::UpdateSettings(false, true);
 
       if (g_settings.display_vsync != old_settings.display_vsync ||

src/util/imgui_fullscreen.cpp

@@ -216,7 +216,7 @@ bool ImGuiFullscreen::Initialize(const char* placeholder_image_path)
   return true;
 }
 
-void ImGuiFullscreen::Shutdown()
+void ImGuiFullscreen::Shutdown(bool clear_state)
 {
   if (s_state.texture_load_thread.joinable())
   {
@@ -235,6 +235,8 @@ void ImGuiFullscreen::Shutdown()
 
   s_state.texture_cache.Clear();
 
+  if (clear_state)
+  {
     s_state.notifications.clear();
     s_state.background_progress_dialogs.clear();
     s_state.fullscreen_footer_text.clear();
@@ -263,6 +265,7 @@ void ImGuiFullscreen::Shutdown()
     s_state.message_dialog_buttons = {};
     s_state.message_dialog_callback = {};
   }
+}
 
 void ImGuiFullscreen::SetSmoothScrolling(bool enabled)
 {

src/util/imgui_fullscreen.h

@@ -130,7 +130,7 @@ void SetFonts(ImFont* medium_font, ImFont* large_font);
 bool UpdateLayoutScale();
 
 /// Shuts down, clearing all state.
-void Shutdown();
+void Shutdown(bool clear_state);
 
 /// Texture cache.
 const std::shared_ptr<GPUTexture>& GetPlaceholderTexture();