HostDisplay: Manually throttle fullscreen UI presentation

Fixes flickering screen in fullscreen with Vulkan.

src/common/vulkan/context.cpp

@@ -269,7 +269,7 @@ Vulkan::Context::GPUNameList Vulkan::Context::EnumerateGPUNames(VkInstance insta
 
 bool Vulkan::Context::Create(std::string_view gpu_name, const WindowInfo* wi,
                              std::unique_ptr<SwapChain>* out_swap_chain, bool threaded_presentation,
-                             bool enable_debug_utils, bool enable_validation_layer)
+                             bool enable_debug_utils, bool enable_validation_layer, bool vsync)
 {
   AssertMsg(!g_vulkan_context, "Has no current context");
 
@@ -349,7 +349,7 @@ bool Vulkan::Context::Create(std::string_view gpu_name, const WindowInfo* wi,
   if (!g_vulkan_context->CreateDevice(surface, enable_validation_layer, nullptr, 0, nullptr, 0, nullptr) ||
       !g_vulkan_context->CreateAllocator() || !g_vulkan_context->CreateGlobalDescriptorPool() ||
       !g_vulkan_context->CreateCommandBuffers() || !g_vulkan_context->CreateTextureStreamBuffer() ||
-      (enable_surface && (*out_swap_chain = SwapChain::Create(wi_copy, surface, true)) == nullptr))
+      (enable_surface && (*out_swap_chain = SwapChain::Create(wi_copy, surface, vsync)) == nullptr))
   {
     // Since we are destroying the instance, we're also responsible for destroying the surface.
     if (surface != VK_NULL_HANDLE)

src/common/vulkan/context.h

@@ -50,7 +50,7 @@ public:
 
   // Creates a new context and sets it up as global.
   static bool Create(std::string_view gpu_name, const WindowInfo* wi, std::unique_ptr<SwapChain>* out_swap_chain,
-                     bool threaded_presentation, bool enable_debug_utils, bool enable_validation_layer);
+                     bool threaded_presentation, bool enable_debug_utils, bool enable_validation_layer, bool vsync);
 
   // Creates a new context from a pre-existing instance.
   static bool CreateFromExistingInstance(VkInstance instance, VkPhysicalDevice gpu, VkSurfaceKHR surface,

src/core/host_display.cpp

@@ -117,6 +117,21 @@ bool HostDisplay::ShouldSkipDisplayingFrame()
   return false;
 }
 
+void HostDisplay::ThrottlePresentation()
+{
+  const float throttle_rate = (m_window_info.surface_refresh_rate > 0.0f) ? m_window_info.surface_refresh_rate : 60.0f;
+
+  const u64 sleep_period = Common::Timer::ConvertNanosecondsToValue(1e+9f / static_cast<double>(throttle_rate));
+  const u64 current_ts = Common::Timer::GetCurrentValue();
+
+  if (current_ts >= m_last_frame_displayed_time)
+    m_last_frame_displayed_time = current_ts + sleep_period;
+  else
+    m_last_frame_displayed_time += sleep_period;
+
+  Common::Timer::SleepUntil(m_last_frame_displayed_time, false);
+}
+
 bool HostDisplay::GetHostRefreshRate(float* refresh_rate)
 {
   if (m_window_info.surface_refresh_rate > 0.0f)

src/core/host_display.h

@@ -67,7 +67,7 @@ public:
   virtual bool HasDevice() const = 0;
   virtual bool HasSurface() const = 0;
 
-  virtual bool CreateDevice(const WindowInfo& wi) = 0;
+  virtual bool CreateDevice(const WindowInfo& wi, bool vsync) = 0;
   virtual bool SetupDevice() = 0;
   virtual bool MakeCurrent() = 0;
   virtual bool DoneCurrent() = 0;
@@ -104,6 +104,7 @@ public:
   virtual bool RenderScreenshot(u32 width, u32 height, std::vector<u32>* out_pixels, u32* out_stride,
                                 GPUTexture::Format* out_format) = 0;
 
+  ALWAYS_INLINE bool IsVsyncEnabled() const { return m_vsync_enabled; }
   virtual void SetVSync(bool enabled) = 0;
 
   /// ImGui context management, usually called by derived classes.
@@ -114,6 +115,7 @@ public:
   bool UsesLowerLeftOrigin() const;
   void SetDisplayMaxFPS(float max_fps);
   bool ShouldSkipDisplayingFrame();
+  void ThrottlePresentation();
 
   void ClearDisplayTexture()
   {
@@ -243,6 +245,7 @@ protected:
 
   bool m_display_changed = false;
   bool m_gpu_timing_enabled = false;
+  bool m_vsync_enabled = false;
 };
 
 /// Returns a pointer to the current host display abstraction. Assumes AcquireHostDisplay() has been caled.

src/duckstation-nogui/nogui_host.cpp

@@ -640,6 +640,8 @@ void NoGUIHost::CPUThreadMainLoop()
 
     Host::PumpMessagesOnCPUThread();
     Host::RenderDisplay(false);
+    if (!g_host_display->IsVsyncEnabled())
+      g_host_display->ThrottlePresentation();
   }
 }
 
@@ -654,7 +656,7 @@ bool NoGUIHost::AcquireHostDisplay(RenderAPI api)
       if (wi.has_value())
       {
         g_host_display = Host::CreateDisplayForAPI(api);
-        if (g_host_display && !g_host_display->CreateDevice(wi.value()))
+        if (g_host_display && !g_host_display->CreateDevice(wi.value(), System::ShouldUseVSync()))
           g_host_display.reset();
       }
 
@@ -675,8 +677,8 @@ bool NoGUIHost::AcquireHostDisplay(RenderAPI api)
     return false;
   }
 
-  if (!g_host_display->MakeCurrent() || !g_host_display->SetupDevice() ||
-      !ImGuiManager::Initialize() || !CommonHost::CreateHostDisplayResources())
+  if (!g_host_display->MakeCurrent() || !g_host_display->SetupDevice() || !ImGuiManager::Initialize() ||
+      !CommonHost::CreateHostDisplayResources())
   {
     ImGuiManager::Shutdown();
     CommonHost::ReleaseHostDisplayResources();

src/duckstation-qt/mainwindow.cpp

@@ -218,7 +218,7 @@ bool MainWindow::createDisplay(bool fullscreen, bool render_to_main)
 
   g_emu_thread->connectDisplaySignals(m_display_widget);
 
-  if (!g_host_display->CreateDevice(wi.value()))
+  if (!g_host_display->CreateDevice(wi.value(), System::ShouldUseVSync()))
   {
     QMessageBox::critical(this, tr("Error"), tr("Failed to create host display device context."));
     destroyDisplayWidget(true);

src/duckstation-qt/qthost.cpp

@@ -754,18 +754,12 @@ bool EmuThread::acquireHostDisplay(RenderAPI api)
 
   m_is_exclusive_fullscreen = g_host_display->IsFullscreen();
 
-  if (m_run_fullscreen_ui)
+  if (m_run_fullscreen_ui && !FullscreenUI::Initialize())
   {
-    if (!FullscreenUI::Initialize())
-    {
-      Log_ErrorPrint("Failed to initialize fullscreen UI");
-      releaseHostDisplay();
-      m_run_fullscreen_ui = false;
-      return false;
-    }
-
-    // start with vsync on
-    g_host_display->SetVSync(true);
+    Log_ErrorPrint("Failed to initialize fullscreen UI");
+    releaseHostDisplay();
+    m_run_fullscreen_ui = false;
+    return false;
   }
 
   return true;
@@ -1439,7 +1433,11 @@ void EmuThread::run()
       m_event_loop->processEvents(QEventLoop::AllEvents);
       CommonHost::PumpMessagesOnCPUThread();
       if (g_host_display)
+      {
         renderDisplay(false);
+        if (!g_host_display->IsVsyncEnabled())
+          g_host_display->ThrottlePresentation();
+      }
     }
   }
 

src/duckstation-regtest/regtest_host.cpp

@@ -352,9 +352,9 @@ void Host::OnInputDeviceDisconnected(const std::string_view& identifier)
   // noop
 }
 
-void* Host::GetTopLevelWindowHandle()
+std::optional<WindowInfo> Host::GetTopLevelWindowInfo()
 {
-  return nullptr;
+  return std::nullopt;
 }
 
 void Host::RefreshGameListAsync(bool invalidate_cache)

src/duckstation-regtest/regtest_host_display.cpp

@@ -38,7 +38,7 @@ bool RegTestHostDisplay::HasSurface() const
   return true;
 }
 
-bool RegTestHostDisplay::CreateDevice(const WindowInfo& wi)
+bool RegTestHostDisplay::CreateDevice(const WindowInfo& wi, bool vsync)
 {
   m_window_info = wi;
   return true;

src/duckstation-regtest/regtest_host_display.h

@@ -15,7 +15,7 @@ public:
   bool HasDevice() const override;
   bool HasSurface() const override;
 
-  bool CreateDevice(const WindowInfo& wi) override;
+  bool CreateDevice(const WindowInfo& wi, bool vsync) override;
   bool SetupDevice() override;
 
   bool MakeCurrent() override;

src/frontend-common/d3d11_host_display.cpp

@@ -194,10 +194,10 @@ bool D3D11HostDisplay::GetHostRefreshRate(float* refresh_rate)
 
 void D3D11HostDisplay::SetVSync(bool enabled)
 {
-  m_vsync = enabled;
+  m_vsync_enabled = enabled;
 }
 
-bool D3D11HostDisplay::CreateDevice(const WindowInfo& wi)
+bool D3D11HostDisplay::CreateDevice(const WindowInfo& wi, bool vsync)
 {
   UINT create_flags = 0;
   if (g_settings.gpu_use_debug_device)
@@ -306,6 +306,7 @@ bool D3D11HostDisplay::CreateDevice(const WindowInfo& wi)
   }
 
   m_window_info = wi;
+  m_vsync_enabled = vsync;
 
   if (m_window_info.type != WindowInfo::Type::Surfaceless && !CreateSwapChain(nullptr))
   {
@@ -675,7 +676,7 @@ bool D3D11HostDisplay::Render(bool skip_present)
   // This blows our our GPU usage number considerably, so read the timestamp before the final blit
   // in this configuration. It does reduce accuracy a little, but better than seeing 100% all of
   // the time, when it's more like a couple of percent.
-  if (m_vsync && m_gpu_timing_enabled)
+  if (m_vsync_enabled && m_gpu_timing_enabled)
     PopTimestampQuery();
 
   RenderDisplay();
@@ -685,13 +686,13 @@ bool D3D11HostDisplay::Render(bool skip_present)
 
   RenderSoftwareCursor();
 
-  if (!m_vsync && m_gpu_timing_enabled)
+  if (!m_vsync_enabled && m_gpu_timing_enabled)
     PopTimestampQuery();
 
-  if (!m_vsync && m_using_allow_tearing)
+  if (!m_vsync_enabled && m_using_allow_tearing)
     m_swap_chain->Present(0, DXGI_PRESENT_ALLOW_TEARING);
   else
-    m_swap_chain->Present(BoolToUInt32(m_vsync), 0);
+    m_swap_chain->Present(BoolToUInt32(m_vsync_enabled), 0);
 
   if (m_gpu_timing_enabled)
     KickTimestampQuery();

src/frontend-common/d3d11_host_display.h

@@ -30,7 +30,7 @@ public:
   bool HasDevice() const override;
   bool HasSurface() const override;
 
-  bool CreateDevice(const WindowInfo& wi) override;
+  bool CreateDevice(const WindowInfo& wi, bool vsync) override;
   bool SetupDevice() override;
 
   bool MakeCurrent() override;
@@ -141,7 +141,6 @@ protected:
   bool m_allow_tearing_supported = false;
   bool m_using_flip_model_swap_chain = true;
   bool m_using_allow_tearing = false;
-  bool m_vsync = true;
 
   FrontendCommon::PostProcessingChain m_post_processing_chain;
   D3D11::Texture m_post_processing_input_texture;

src/frontend-common/d3d12_host_display.cpp

@@ -139,10 +139,10 @@ bool D3D12HostDisplay::GetHostRefreshRate(float* refresh_rate)
 
 void D3D12HostDisplay::SetVSync(bool enabled)
 {
-  m_vsync = enabled;
+  m_vsync_enabled = enabled;
 }
 
-bool D3D12HostDisplay::CreateDevice(const WindowInfo& wi)
+bool D3D12HostDisplay::CreateDevice(const WindowInfo& wi, bool vsync)
 {
   ComPtr<IDXGIFactory> temp_dxgi_factory;
   HRESULT hr = CreateDXGIFactory(IID_PPV_ARGS(temp_dxgi_factory.GetAddressOf()));
@@ -198,6 +198,7 @@ bool D3D12HostDisplay::CreateDevice(const WindowInfo& wi)
   }
 
   m_window_info = wi;
+  m_vsync_enabled = vsync;
 
   if (m_window_info.type != WindowInfo::Type::Surfaceless && !CreateSwapChain(nullptr))
   {
@@ -599,10 +600,10 @@ bool D3D12HostDisplay::Render(bool skip_present)
   swap_chain_buf.TransitionToState(D3D12_RESOURCE_STATE_PRESENT);
   g_d3d12_context->ExecuteCommandList(false);
 
-  if (!m_vsync && m_using_allow_tearing)
+  if (!m_vsync_enabled && m_using_allow_tearing)
     m_swap_chain->Present(0, DXGI_PRESENT_ALLOW_TEARING);
   else
-    m_swap_chain->Present(BoolToUInt32(m_vsync), 0);
+    m_swap_chain->Present(BoolToUInt32(m_vsync_enabled), 0);
 
   return true;
 }

src/frontend-common/d3d12_host_display.h

@@ -32,7 +32,7 @@ public:
   bool HasDevice() const override;
   bool HasSurface() const override;
 
-  bool CreateDevice(const WindowInfo& wi) override;
+  bool CreateDevice(const WindowInfo& wi, bool vsync) override;
   bool SetupDevice() override;
 
   bool MakeCurrent() override;
@@ -137,5 +137,4 @@ protected:
 
   bool m_allow_tearing_supported = false;
   bool m_using_allow_tearing = false;
-  bool m_vsync = true;
 };

src/frontend-common/fullscreen_ui.cpp

@@ -638,7 +638,6 @@ void FullscreenUI::OnSystemDestroyed()
   if (!IsInitialized())
     return;
 
-  g_host_display->SetVSync(true);
   s_pause_menu_was_open = false;
   SwitchToLanding();
 }
@@ -668,15 +667,7 @@ void FullscreenUI::PauseForMenuOpen()
 {
   s_was_paused_on_quick_menu_open = (System::GetState() == System::State::Paused);
   if (g_settings.pause_on_menu && !s_was_paused_on_quick_menu_open)
-  {
-    Host::RunOnCPUThread([]() {
-      System::PauseSystem(true);
-
-      // force vsync on when pausing
-      if (g_host_display)
-        g_host_display->SetVSync(true);
-    });
-  }
+    Host::RunOnCPUThread([]() { System::PauseSystem(true); });
 
   s_pause_menu_was_open = true;
 }

src/frontend-common/opengl_host_display.cpp

@@ -209,7 +209,7 @@ bool OpenGLHostDisplay::SupportsTextureFormat(GPUTexture::Format format) const
 
 void OpenGLHostDisplay::SetVSync(bool enabled)
 {
-  if (m_gl_context->GetWindowInfo().type == WindowInfo::Type::Surfaceless)
+  if (m_vsync_enabled == enabled || m_gl_context->GetWindowInfo().type == WindowInfo::Type::Surfaceless)
     return;
 
   // Window framebuffer has to be bound to call SetSwapInterval.
@@ -218,6 +218,7 @@ void OpenGLHostDisplay::SetVSync(bool enabled)
   glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
   m_gl_context->SetSwapInterval(enabled ? 1 : 0);
   glBindFramebuffer(GL_DRAW_FRAMEBUFFER, current_fbo);
+  m_vsync_enabled = enabled;
 }
 
 const char* OpenGLHostDisplay::GetGLSLVersionString() const
@@ -281,7 +282,7 @@ bool OpenGLHostDisplay::HasSurface() const
   return m_window_info.type != WindowInfo::Type::Surfaceless;
 }
 
-bool OpenGLHostDisplay::CreateDevice(const WindowInfo& wi)
+bool OpenGLHostDisplay::CreateDevice(const WindowInfo& wi, bool vsync)
 {
   m_gl_context = GL::Context::Create(wi);
   if (!m_gl_context)
@@ -292,6 +293,7 @@ bool OpenGLHostDisplay::CreateDevice(const WindowInfo& wi)
   }
 
   m_window_info = m_gl_context->GetWindowInfo();
+  SetVSync(vsync);
   return true;
 }
 
@@ -328,9 +330,6 @@ bool OpenGLHostDisplay::SetupDevice()
   if (!CreateResources())
     return false;
 
-  // Start with vsync on.
-  SetVSync(true);
-
   return true;
 }
 

src/frontend-common/opengl_host_display.h

@@ -23,7 +23,7 @@ public:
   bool HasDevice() const override;
   bool HasSurface() const override;
 
-  bool CreateDevice(const WindowInfo& wi) override;
+  bool CreateDevice(const WindowInfo& wi, bool vsync) override;
   bool SetupDevice() override;
 
   bool MakeCurrent() override;

src/frontend-common/vulkan_host_display.cpp

@@ -95,6 +95,7 @@ bool VulkanHostDisplay::ChangeWindow(const WindowInfo& new_wi)
   }
 
   m_window_info = m_swap_chain->GetWindowInfo();
+  m_vsync_enabled = m_swap_chain->IsVSyncEnabled();
   return true;
 }
 
@@ -106,6 +107,7 @@ void VulkanHostDisplay::ResizeWindow(s32 new_window_width, s32 new_window_height
     Panic("Failed to resize swap chain");
 
   m_window_info = m_swap_chain->GetWindowInfo();
+  m_vsync_enabled = m_swap_chain->IsVSyncEnabled();
 }
 
 bool VulkanHostDisplay::SupportsFullscreen() const
@@ -206,19 +208,31 @@ bool VulkanHostDisplay::SupportsTextureFormat(GPUTexture::Format format) const
 
 void VulkanHostDisplay::SetVSync(bool enabled)
 {
-  if (!m_swap_chain)
+  if (!m_swap_chain || m_swap_chain->IsVSyncEnabled() == enabled)
     return;
 
   // This swap chain should not be used by the current buffer, thus safe to destroy.
   g_vulkan_context->WaitForGPUIdle();
   m_swap_chain->SetVSync(enabled);
+  m_vsync_enabled = m_swap_chain->IsVSyncEnabled();
 }
 
-bool VulkanHostDisplay::CreateDevice(const WindowInfo& wi)
+bool VulkanHostDisplay::CreateDevice(const WindowInfo& wi, bool vsync)
 {
   WindowInfo local_wi(wi);
-  if (!Vulkan::Context::Create(g_settings.gpu_adapter, &local_wi, &m_swap_chain, g_settings.gpu_threaded_presentation,
-                               g_settings.gpu_use_debug_device, false))
+  bool result =
+    Vulkan::Context::Create(g_settings.gpu_adapter, &local_wi, &m_swap_chain, g_settings.gpu_threaded_presentation,
+                            g_settings.gpu_use_debug_device, g_settings.gpu_use_debug_device, vsync);
+
+  // If validation layers were enabled, try without.
+  if (!result && g_settings.gpu_use_debug_device)
+  {
+    Log_WarningPrintf("Failed to create Vulkan context with validation layers, trying without.");
+    result = Vulkan::Context::Create(g_settings.gpu_adapter, &local_wi, &m_swap_chain,
+                                     g_settings.gpu_threaded_presentation, false, false, vsync);
+  }
+
+  if (!result)
   {
     Log_ErrorPrintf("Failed to create Vulkan context");
     m_window_info = {};
@@ -231,6 +245,7 @@ bool VulkanHostDisplay::CreateDevice(const WindowInfo& wi)
                  g_vulkan_context->GetDeviceDriverProperties().driverID == VK_DRIVER_ID_QUALCOMM_PROPRIETARY);
 
   m_window_info = m_swap_chain ? m_swap_chain->GetWindowInfo() : local_wi;
+  m_vsync_enabled = m_swap_chain ? m_swap_chain->IsVSyncEnabled() : false;
   return true;
 }
 

src/frontend-common/vulkan_host_display.h

@@ -27,7 +27,7 @@ public:
   bool HasDevice() const override;
   bool HasSurface() const override;
 
-  bool CreateDevice(const WindowInfo& wi) override;
+  bool CreateDevice(const WindowInfo& wi, bool vsync) override;
   bool SetupDevice() override;
 
   bool MakeCurrent() override;