HostInterface: Add function to switch between sw/hw rendering

src/core/gpu.h

@@ -105,6 +105,8 @@ public:
   GPU();
   virtual ~GPU();
 
+  virtual bool IsHardwareRenderer() const = 0;
+
   virtual bool Initialize(HostDisplay* host_display, System* system, DMA* dma,
                           InterruptController* interrupt_controller, Timers* timers);
   virtual void Reset();

src/core/gpu_hw.cpp

@@ -15,6 +15,11 @@ GPU_HW::GPU_HW() : GPU()
 
 GPU_HW::~GPU_HW() = default;
 
+bool GPU_HW::IsHardwareRenderer() const
+{
+  return true;
+}
+
 bool GPU_HW::Initialize(HostDisplay* host_display, System* system, DMA* dma, InterruptController* interrupt_controller,
                         Timers* timers)
 {

src/core/gpu_hw.h

@@ -29,6 +29,8 @@ public:
   GPU_HW();
   virtual ~GPU_HW();
 
+  virtual bool IsHardwareRenderer() const override;
+
   virtual bool Initialize(HostDisplay* host_display, System* system, DMA* dma,
                           InterruptController* interrupt_controller, Timers* timers) override;
   virtual void Reset() override;

src/core/gpu_sw.cpp

@@ -15,6 +15,11 @@ GPU_SW::~GPU_SW()
   m_host_display->SetDisplayTexture(nullptr, 0, 0, 0, 0, 0, 0, 1.0f);
 }
 
+bool GPU_SW::IsHardwareRenderer() const
+{
+  return false;
+}
+
 bool GPU_SW::Initialize(HostDisplay* host_display, System* system, DMA* dma, InterruptController* interrupt_controller,
                         Timers* timers)
 {

src/core/gpu_sw.h

@@ -12,6 +12,8 @@ public:
   GPU_SW();
   ~GPU_SW() override;
 
+  bool IsHardwareRenderer() const override;
+
   bool Initialize(HostDisplay* host_display, System* system, DMA* dma, InterruptController* interrupt_controller,
                   Timers* timers) override;
   void Reset() override;

src/core/host_interface.cpp

@@ -515,7 +515,6 @@ std::string HostInterface::GetGameListDatabaseFileName() const
 
 void HostInterface::UpdateSettings(const std::function<void()>& apply_callback)
 {
-  // TODO: Should we move this to the base class?
   const GPURenderer old_gpu_renderer = m_settings.gpu_renderer;
   const u32 old_gpu_resolution_scale = m_settings.gpu_resolution_scale;
   const bool old_gpu_true_color = m_settings.gpu_true_color;
@@ -528,7 +527,6 @@ void HostInterface::UpdateSettings(const std::function<void()>& apply_callback)
 
   apply_callback();
 
-  // TODO: Fast path for hardware->software switches
   if (m_settings.gpu_renderer != old_gpu_renderer)
     SwitchGPURenderer();
 
@@ -549,6 +547,18 @@ void HostInterface::UpdateSettings(const std::function<void()>& apply_callback)
     m_display->SetDisplayLinearFiltering(m_settings.display_linear_filtering);
 }
 
+void HostInterface::ToggleSoftwareRendering()
+{
+  if (!m_system || m_settings.gpu_renderer == GPURenderer::Software)
+    return;
+
+  const GPURenderer new_renderer =
+    m_system->GetGPU()->IsHardwareRenderer() ? GPURenderer::Software : m_settings.gpu_renderer;
+
+  AddFormattedOSDMessage(2.0f, "Switching to %s renderer...", Settings::GetRendererDisplayName(new_renderer));
+  m_system->RecreateGPU(new_renderer);
+}
+
 void HostInterface::RunFrame()
 {
   m_frame_timer.Reset();

src/core/host_interface.h

@@ -104,8 +104,13 @@ protected:
   /// Returns the path of the game database cache file.
   std::string GetGameListDatabaseFileName() const;
 
+  /// Applies new settings, updating internal state as needed. apply_callback should call m_settings.Load() after
+  /// locking any required mutexes.
   void UpdateSettings(const std::function<void()>& apply_callback);
 
+  /// Quick switch between software and hardware rendering.
+  void ToggleSoftwareRendering();
+
   void RunFrame();
 
   /// Throttles the system, i.e. sleeps until it's time to execute the next frame.

src/core/system.cpp

@@ -36,8 +36,8 @@ System::System(HostInterface* host_interface) : m_host_interface(host_interface)
   m_spu = std::make_unique<SPU>();
   m_mdec = std::make_unique<MDEC>();
   m_sio = std::make_unique<SIO>();
-  m_region = host_interface->GetSettings().region;
-  m_cpu_execution_mode = host_interface->GetSettings().cpu_execution_mode;
+  m_region = host_interface->m_settings.region;
+  m_cpu_execution_mode = host_interface->m_settings.cpu_execution_mode;
 }
 
 System::~System() = default;
@@ -45,13 +45,13 @@ System::~System() = default;
 std::unique_ptr<System> System::Create(HostInterface* host_interface)
 {
   std::unique_ptr<System> system(new System(host_interface));
-  if (!system->CreateGPU())
+  if (!system->CreateGPU(host_interface->m_settings.gpu_renderer))
     return {};
 
   return system;
 }
 
-bool System::RecreateGPU()
+bool System::RecreateGPU(GPURenderer renderer)
 {
   // save current state
   std::unique_ptr<ByteStream> state_stream = ByteStream_CreateGrowableMemoryStream();
@@ -62,7 +62,7 @@ bool System::RecreateGPU()
 
   // create new renderer
   m_gpu.reset();
-  if (!CreateGPU())
+  if (!CreateGPU(renderer))
   {
     Panic("Failed to recreate GPU");
     return false;
@@ -193,9 +193,9 @@ void System::InitializeComponents()
   m_mdec->Initialize(this, m_dma.get());
 }
 
-bool System::CreateGPU()
+bool System::CreateGPU(GPURenderer renderer)
 {
-  switch (m_host_interface->GetSettings().gpu_renderer)
+  switch (renderer)
   {
     case GPURenderer::HardwareOpenGL:
       m_gpu = m_host_interface->GetDisplay()->GetRenderAPI() == HostDisplay::RenderAPI::OpenGLES ?
@@ -220,7 +220,6 @@ bool System::CreateGPU()
   {
     Log_ErrorPrintf("Failed to initialize GPU, falling back to software");
     m_gpu.reset();
-    m_host_interface->GetSettings().gpu_renderer = GPURenderer::Software;
     m_gpu = GPU::CreateSoftwareRenderer();
     if (!m_gpu->Initialize(m_host_interface->GetDisplay(), this, m_dma.get(), m_interrupt_controller.get(),
                            m_timers.get()))

src/core/system.h

@@ -68,7 +68,7 @@ public:
   bool SaveState(ByteStream* state);
 
   /// Recreates the GPU component, saving/loading the state so it is preserved. Call when the GPU renderer changes.
-  bool RecreateGPU();
+  bool RecreateGPU(GPURenderer renderer);
 
   /// Updates GPU settings, without recreating the renderer.
   void UpdateGPUSettings();
@@ -98,7 +98,7 @@ private:
   System(HostInterface* host_interface);
 
   bool DoState(StateWrapper& sw);
-  bool CreateGPU();
+  bool CreateGPU(GPURenderer renderer);
 
   void InitializeComponents();
 

src/duckstation/sdl_host_interface.cpp

@@ -419,7 +419,7 @@ void SDLHostInterface::HandleSDLKeyEvent(const SDL_Event* event)
 
     case SDL_SCANCODE_END: {
       if (pressed)
-        DoToggleSoftwareRendering();
+        ToggleSoftwareRendering();
     }
     break;
 
@@ -1549,31 +1549,6 @@ void SDLHostInterface::DoFrameStep()
   m_paused = false;
 }
 
-void SDLHostInterface::DoToggleSoftwareRendering()
-{
-  if (!m_system)
-    return;
-
-  if (m_settings.gpu_renderer != GPURenderer::Software)
-  {
-    m_settings.gpu_renderer = GPURenderer::Software;
-    AddOSDMessage("Switched to software GPU renderer.");
-  }
-  else
-  {
-#ifdef WIN32
-    m_settings.gpu_renderer = m_display->GetRenderAPI() == HostDisplay::RenderAPI::D3D11 ? GPURenderer::HardwareD3D11 :
-                                                                                           GPURenderer::HardwareOpenGL;
-#else
-    m_settings.gpu_renderer = GPURenderer::HardwareOpenGL;
-#endif
-
-    AddOSDMessage("Switched to hardware GPU renderer.");
-  }
-
-  m_system->RecreateGPU();
-}
-
 void SDLHostInterface::DoToggleFullscreen()
 {
   m_settings.display_fullscreen = !m_settings.display_fullscreen;

src/duckstation/sdl_host_interface.h

@@ -99,7 +99,6 @@ private:
   void DoSaveState(u32 index);
   void DoTogglePause();
   void DoFrameStep();
-  void DoToggleSoftwareRendering();
   void DoToggleFullscreen();
   void DoModifyInternalResolution(s32 increment);