video_core: add null backend

src/common/settings.h

@@ -19,6 +19,7 @@ namespace Settings {
 enum class RendererBackend : u32 {
     OpenGL = 0,
     Vulkan = 1,
+    Null = 2,
 };
 
 enum class ShaderBackend : u32 {
@@ -411,7 +412,7 @@ struct Values {
 
     // Renderer
     SwitchableSetting<RendererBackend, true> renderer_backend{
-        RendererBackend::Vulkan, RendererBackend::OpenGL, RendererBackend::Vulkan, "backend"};
+        RendererBackend::Vulkan, RendererBackend::OpenGL, RendererBackend::Null, "backend"};
     Setting<bool> renderer_debug{false, "debug"};
     Setting<bool> renderer_shader_feedback{false, "shader_feedback"};
     Setting<bool> enable_nsight_aftermath{false, "nsight_aftermath"};

src/core/telemetry_session.cpp

@@ -55,6 +55,8 @@ static const char* TranslateRenderer(Settings::RendererBackend backend) {
         return "OpenGL";
     case Settings::RendererBackend::Vulkan:
         return "Vulkan";
+    case Settings::RendererBackend::Null:
+        return "Null";
     }
     return "Unknown";
 }

src/video_core/CMakeLists.txt

@@ -91,6 +91,10 @@ add_library(video_core STATIC
     rasterizer_interface.h
     renderer_base.cpp
     renderer_base.h
+    renderer_null/null_rasterizer.cpp
+    renderer_null/null_rasterizer.h
+    renderer_null/renderer_null.cpp
+    renderer_null/renderer_null.h
     renderer_opengl/gl_buffer_cache.cpp
     renderer_opengl/gl_buffer_cache.h
     renderer_opengl/gl_compute_pipeline.cpp

src/video_core/renderer_null/null_rasterizer.cpp

@@ -0,0 +1,90 @@
+// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "video_core/host1x/host1x.h"
+#include "video_core/memory_manager.h"
+#include "video_core/renderer_null/null_rasterizer.h"
+
+namespace Null {
+
+AccelerateDMA::AccelerateDMA() = default;
+
+bool AccelerateDMA::BufferCopy(GPUVAddr start_address, GPUVAddr end_address, u64 amount) {
+    return true;
+}
+bool AccelerateDMA::BufferClear(GPUVAddr src_address, u64 amount, u32 value) {
+    return true;
+}
+
+RasterizerNull::RasterizerNull(Core::Memory::Memory& cpu_memory_, Tegra::GPU& gpu)
+    : RasterizerAccelerated(cpu_memory_), m_gpu{gpu} {}
+RasterizerNull::~RasterizerNull() = default;
+
+void RasterizerNull::Draw(bool is_indexed, u32 instance_count) {}
+void RasterizerNull::Clear(u32 layer_count) {}
+void RasterizerNull::DispatchCompute() {}
+void RasterizerNull::ResetCounter(VideoCore::QueryType type) {}
+void RasterizerNull::Query(GPUVAddr gpu_addr, VideoCore::QueryType type,
+                           std::optional<u64> timestamp) {
+    if (!gpu_memory) {
+        return;
+    }
+
+    gpu_memory->Write(gpu_addr, u64{0});
+    if (timestamp) {
+        gpu_memory->Write(gpu_addr + 8, *timestamp);
+    }
+}
+void RasterizerNull::BindGraphicsUniformBuffer(size_t stage, u32 index, GPUVAddr gpu_addr,
+                                               u32 size) {}
+void RasterizerNull::DisableGraphicsUniformBuffer(size_t stage, u32 index) {}
+void RasterizerNull::FlushAll() {}
+void RasterizerNull::FlushRegion(VAddr addr, u64 size) {}
+bool RasterizerNull::MustFlushRegion(VAddr addr, u64 size) {
+    return false;
+}
+void RasterizerNull::InvalidateRegion(VAddr addr, u64 size) {}
+void RasterizerNull::OnCPUWrite(VAddr addr, u64 size) {}
+void RasterizerNull::InvalidateGPUCache() {}
+void RasterizerNull::UnmapMemory(VAddr addr, u64 size) {}
+void RasterizerNull::ModifyGPUMemory(size_t as_id, GPUVAddr addr, u64 size) {}
+void RasterizerNull::SignalFence(std::function<void()>&& func) {
+    func();
+}
+void RasterizerNull::SyncOperation(std::function<void()>&& func) {
+    func();
+}
+void RasterizerNull::SignalSyncPoint(u32 value) {
+    auto& syncpoint_manager = m_gpu.Host1x().GetSyncpointManager();
+    syncpoint_manager.IncrementGuest(value);
+    syncpoint_manager.IncrementHost(value);
+}
+void RasterizerNull::SignalReference() {}
+void RasterizerNull::ReleaseFences() {}
+void RasterizerNull::FlushAndInvalidateRegion(VAddr addr, u64 size) {}
+void RasterizerNull::WaitForIdle() {}
+void RasterizerNull::FragmentBarrier() {}
+void RasterizerNull::TiledCacheBarrier() {}
+void RasterizerNull::FlushCommands() {}
+void RasterizerNull::TickFrame() {}
+Tegra::Engines::AccelerateDMAInterface& RasterizerNull::AccessAccelerateDMA() {
+    return m_accelerate_dma;
+}
+bool RasterizerNull::AccelerateSurfaceCopy(const Tegra::Engines::Fermi2D::Surface& src,
+                                           const Tegra::Engines::Fermi2D::Surface& dst,
+                                           const Tegra::Engines::Fermi2D::Config& copy_config) {
+    return true;
+}
+void RasterizerNull::AccelerateInlineToMemory(GPUVAddr address, size_t copy_size,
+                                              std::span<const u8> memory) {}
+bool RasterizerNull::AccelerateDisplay(const Tegra::FramebufferConfig& config,
+                                       VAddr framebuffer_addr, u32 pixel_stride) {
+    return true;
+}
+void RasterizerNull::LoadDiskResources(u64 title_id, std::stop_token stop_loading,
+                                       const VideoCore::DiskResourceLoadCallback& callback) {}
+void RasterizerNull::InitializeChannel(Tegra::Control::ChannelState& channel) {}
+void RasterizerNull::BindChannel(Tegra::Control::ChannelState& channel) {}
+void RasterizerNull::ReleaseChannel(s32 channel_id) {}
+
+} // namespace Null

src/video_core/renderer_null/null_rasterizer.h

@@ -0,0 +1,78 @@
+// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include "common/common_types.h"
+#include "video_core/control/channel_state_cache.h"
+#include "video_core/engines/maxwell_dma.h"
+#include "video_core/rasterizer_accelerated.h"
+#include "video_core/rasterizer_interface.h"
+
+namespace Core {
+class System;
+}
+
+namespace Null {
+
+class RasterizerNull;
+
+class AccelerateDMA : public Tegra::Engines::AccelerateDMAInterface {
+public:
+    explicit AccelerateDMA();
+    bool BufferCopy(GPUVAddr start_address, GPUVAddr end_address, u64 amount) override;
+    bool BufferClear(GPUVAddr src_address, u64 amount, u32 value) override;
+};
+
+class RasterizerNull final : public VideoCore::RasterizerAccelerated,
+                             protected VideoCommon::ChannelSetupCaches<VideoCommon::ChannelInfo> {
+public:
+    explicit RasterizerNull(Core::Memory::Memory& cpu_memory, Tegra::GPU& gpu);
+    ~RasterizerNull() override;
+
+    void Draw(bool is_indexed, u32 instance_count) override;
+    void Clear(u32 layer_count) override;
+    void DispatchCompute() override;
+    void ResetCounter(VideoCore::QueryType type) override;
+    void Query(GPUVAddr gpu_addr, VideoCore::QueryType type, std::optional<u64> timestamp) override;
+    void BindGraphicsUniformBuffer(size_t stage, u32 index, GPUVAddr gpu_addr, u32 size) override;
+    void DisableGraphicsUniformBuffer(size_t stage, u32 index) override;
+    void FlushAll() override;
+    void FlushRegion(VAddr addr, u64 size) override;
+    bool MustFlushRegion(VAddr addr, u64 size) override;
+    void InvalidateRegion(VAddr addr, u64 size) override;
+    void OnCPUWrite(VAddr addr, u64 size) override;
+    void InvalidateGPUCache() override;
+    void UnmapMemory(VAddr addr, u64 size) override;
+    void ModifyGPUMemory(size_t as_id, GPUVAddr addr, u64 size) override;
+    void SignalFence(std::function<void()>&& func) override;
+    void SyncOperation(std::function<void()>&& func) override;
+    void SignalSyncPoint(u32 value) override;
+    void SignalReference() override;
+    void ReleaseFences() override;
+    void FlushAndInvalidateRegion(VAddr addr, u64 size) override;
+    void WaitForIdle() override;
+    void FragmentBarrier() override;
+    void TiledCacheBarrier() override;
+    void FlushCommands() override;
+    void TickFrame() override;
+    bool AccelerateSurfaceCopy(const Tegra::Engines::Fermi2D::Surface& src,
+                               const Tegra::Engines::Fermi2D::Surface& dst,
+                               const Tegra::Engines::Fermi2D::Config& copy_config) override;
+    Tegra::Engines::AccelerateDMAInterface& AccessAccelerateDMA() override;
+    void AccelerateInlineToMemory(GPUVAddr address, size_t copy_size,
+                                  std::span<const u8> memory) override;
+    bool AccelerateDisplay(const Tegra::FramebufferConfig& config, VAddr framebuffer_addr,
+                           u32 pixel_stride) override;
+    void LoadDiskResources(u64 title_id, std::stop_token stop_loading,
+                           const VideoCore::DiskResourceLoadCallback& callback) override;
+    void InitializeChannel(Tegra::Control::ChannelState& channel) override;
+    void BindChannel(Tegra::Control::ChannelState& channel) override;
+    void ReleaseChannel(s32 channel_id) override;
+
+private:
+    Tegra::GPU& m_gpu;
+    AccelerateDMA m_accelerate_dma;
+};
+
+} // namespace Null

src/video_core/renderer_null/renderer_null.cpp

@@ -0,0 +1,24 @@
+// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "video_core/renderer_null/renderer_null.h"
+
+namespace Null {
+
+RendererNull::RendererNull(Core::Frontend::EmuWindow& emu_window, Core::Memory::Memory& cpu_memory,
+                           Tegra::GPU& gpu,
+                           std::unique_ptr<Core::Frontend::GraphicsContext> context_)
+    : RendererBase(emu_window, std::move(context_)), m_gpu(gpu), m_rasterizer(cpu_memory, gpu) {}
+
+RendererNull::~RendererNull() = default;
+
+void RendererNull::SwapBuffers(const Tegra::FramebufferConfig* framebuffer) {
+    if (!framebuffer) {
+        return;
+    }
+
+    m_gpu.RendererFrameEndNotify();
+    render_window.OnFrameDisplayed();
+}
+
+} // namespace Null

src/video_core/renderer_null/renderer_null.h

@@ -0,0 +1,36 @@
+// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <memory>
+#include <string>
+
+#include "video_core/renderer_base.h"
+#include "video_core/renderer_null/null_rasterizer.h"
+
+namespace Null {
+
+class RendererNull final : public VideoCore::RendererBase {
+public:
+    explicit RendererNull(Core::Frontend::EmuWindow& emu_window, Core::Memory::Memory& cpu_memory,
+                          Tegra::GPU& gpu,
+                          std::unique_ptr<Core::Frontend::GraphicsContext> context);
+    ~RendererNull() override;
+
+    void SwapBuffers(const Tegra::FramebufferConfig* framebuffer) override;
+
+    VideoCore::RasterizerInterface* ReadRasterizer() override {
+        return &m_rasterizer;
+    }
+
+    [[nodiscard]] std::string GetDeviceVendor() const override {
+        return "NULL";
+    }
+
+private:
+    Tegra::GPU& m_gpu;
+    RasterizerNull m_rasterizer;
+};
+
+} // namespace Null

src/video_core/video_core.cpp

@@ -7,6 +7,7 @@
 #include "common/settings.h"
 #include "core/core.h"
 #include "video_core/renderer_base.h"
+#include "video_core/renderer_null/renderer_null.h"
 #include "video_core/renderer_opengl/renderer_opengl.h"
 #include "video_core/renderer_vulkan/renderer_vulkan.h"
 #include "video_core/video_core.h"
@@ -26,6 +27,9 @@ std::unique_ptr<VideoCore::RendererBase> CreateRenderer(
     case Settings::RendererBackend::Vulkan:
         return std::make_unique<Vulkan::RendererVulkan>(telemetry_session, emu_window, cpu_memory,
                                                         gpu, std::move(context));
+    case Settings::RendererBackend::Null:
+        return std::make_unique<Null::RendererNull>(emu_window, cpu_memory, gpu,
+                                                    std::move(context));
     default:
         return nullptr;
     }

src/yuzu/bootmanager.cpp

@@ -237,8 +237,7 @@ private:
     GRenderWindow* render_window;
 };
 
-class OpenGLRenderWidget : public RenderWidget {
-public:
+struct OpenGLRenderWidget : public RenderWidget {
     explicit OpenGLRenderWidget(GRenderWindow* parent) : RenderWidget(parent) {
         windowHandle()->setSurfaceType(QWindow::OpenGLSurface);
     }
@@ -251,13 +250,16 @@ private:
     std::unique_ptr<Core::Frontend::GraphicsContext> context;
 };
 
-class VulkanRenderWidget : public RenderWidget {
-public:
+struct VulkanRenderWidget : public RenderWidget {
     explicit VulkanRenderWidget(GRenderWindow* parent) : RenderWidget(parent) {
         windowHandle()->setSurfaceType(QWindow::VulkanSurface);
     }
 };
 
+struct NullRenderWidget : public RenderWidget {
+    explicit NullRenderWidget(GRenderWindow* parent) : RenderWidget(parent) {}
+};
+
 static Core::Frontend::WindowSystemType GetWindowSystemType() {
     // Determine WSI type based on Qt platform.
     QString platform_name = QGuiApplication::platformName();
@@ -874,6 +876,9 @@ bool GRenderWindow::InitRenderTarget() {
             return false;
         }
         break;
+    case Settings::RendererBackend::Null:
+        InitializeNull();
+        break;
     }
 
     // Update the Window System information with the new render target
@@ -970,6 +975,11 @@ bool GRenderWindow::InitializeVulkan() {
     return true;
 }
 
+void GRenderWindow::InitializeNull() {
+    child_widget = new NullRenderWidget(this);
+    main_context = std::make_unique<DummyContext>();
+}
+
 bool GRenderWindow::LoadOpenGL() {
     auto context = CreateSharedContext();
     auto scope = context->Acquire();

src/yuzu/bootmanager.h

@@ -218,6 +218,7 @@ private:
 
     bool InitializeOpenGL();
     bool InitializeVulkan();
+    void InitializeNull();
     bool LoadOpenGL();
     QStringList GetUnsupportedGLExtensions() const;
 

src/yuzu/configuration/configure_graphics.cpp

@@ -260,6 +260,7 @@ void ConfigureGraphics::ApplyConfiguration() {
             Settings::values.renderer_backend.SetValue(GetCurrentGraphicsBackend());
             switch (GetCurrentGraphicsBackend()) {
             case Settings::RendererBackend::OpenGL:
+            case Settings::RendererBackend::Null:
                 Settings::values.shader_backend.SetGlobal(false);
                 Settings::values.vulkan_device.SetGlobal(true);
                 Settings::values.shader_backend.SetValue(shader_backend);
@@ -348,6 +349,10 @@ void ConfigureGraphics::UpdateAPILayout() {
         ui->device_widget->setVisible(true);
         ui->backend_widget->setVisible(false);
         break;
+    case Settings::RendererBackend::Null:
+        ui->device_widget->setVisible(false);
+        ui->backend_widget->setVisible(false);
+        break;
     }
 }
 

src/yuzu/configuration/configure_graphics.ui

@@ -139,6 +139,11 @@
                   <string notr="true">Vulkan</string>
                  </property>
                 </item>
+                <item>
+                 <property name="text">
+                  <string>None</string>
+                 </property>
+                </item>
                </widget>
               </item>
              </layout>

src/yuzu/main.cpp

@@ -1007,29 +1007,11 @@ void GMainWindow::InitializeWidgets() {
     renderer_status_button->setObjectName(QStringLiteral("RendererStatusBarButton"));
     renderer_status_button->setCheckable(true);
     renderer_status_button->setFocusPolicy(Qt::NoFocus);
-    connect(renderer_status_button, &QPushButton::toggled, [this](bool checked) {
-        renderer_status_button->setText(checked ? tr("VULKAN") : tr("OPENGL"));
-    });
-    renderer_status_button->toggle();
-
+    connect(renderer_status_button, &QPushButton::clicked, this, &GMainWindow::OnToggleGraphicsAPI);
+    UpdateAPIText();
+    renderer_status_button->setCheckable(true);
     renderer_status_button->setChecked(Settings::values.renderer_backend.GetValue() ==
                                        Settings::RendererBackend::Vulkan);
-    connect(renderer_status_button, &QPushButton::clicked, [this] {
-        if (emulation_running) {
-            return;
-        }
-        if (renderer_status_button->isChecked()) {
-            Settings::values.renderer_backend.SetValue(Settings::RendererBackend::Vulkan);
-        } else {
-            Settings::values.renderer_backend.SetValue(Settings::RendererBackend::OpenGL);
-            if (Settings::values.scaling_filter.GetValue() == Settings::ScalingFilter::Fsr) {
-                Settings::values.scaling_filter.SetValue(Settings::ScalingFilter::NearestNeighbor);
-                UpdateFilterText();
-            }
-        }
-
-        system->ApplySettings();
-    });
     statusBar()->insertPermanentWidget(0, renderer_status_button);
 
     statusBar()->setVisible(true);
@@ -3248,6 +3230,18 @@ void GMainWindow::OnToggleAdaptingFilter() {
     UpdateFilterText();
 }
 
+void GMainWindow::OnToggleGraphicsAPI() {
+    auto api = Settings::values.renderer_backend.GetValue();
+    if (api == Settings::RendererBackend::OpenGL) {
+        api = Settings::RendererBackend::Vulkan;
+    } else {
+        api = Settings::RendererBackend::OpenGL;
+    }
+    Settings::values.renderer_backend.SetValue(api);
+    renderer_status_button->setChecked(api == Settings::RendererBackend::Vulkan);
+    UpdateAPIText();
+}
+
 void GMainWindow::OnConfigurePerGame() {
     const u64 title_id = system->GetCurrentProcessProgramID();
     OpenPerGameConfiguration(title_id, current_game_path.toStdString());
@@ -3568,6 +3562,21 @@ void GMainWindow::UpdateDockedButton() {
     dock_status_button->setText(is_docked ? tr("DOCKED") : tr("HANDHELD"));
 }
 
+void GMainWindow::UpdateAPIText() {
+    const auto api = Settings::values.renderer_backend.GetValue();
+    switch (api) {
+    case Settings::RendererBackend::OpenGL:
+        renderer_status_button->setText(tr("OPENGL"));
+        break;
+    case Settings::RendererBackend::Vulkan:
+        renderer_status_button->setText(tr("VULKAN"));
+        break;
+    case Settings::RendererBackend::Null:
+        renderer_status_button->setText(tr("NULL"));
+        break;
+    }
+}
+
 void GMainWindow::UpdateFilterText() {
     const auto filter = Settings::values.scaling_filter.GetValue();
     switch (filter) {
@@ -3613,6 +3622,7 @@ void GMainWindow::UpdateAAText() {
 void GMainWindow::UpdateStatusButtons() {
     renderer_status_button->setChecked(Settings::values.renderer_backend.GetValue() ==
                                        Settings::RendererBackend::Vulkan);
+    UpdateAPIText();
     UpdateGPUAccuracyButton();
     UpdateDockedButton();
     UpdateFilterText();

src/yuzu/main.h

@@ -307,6 +307,7 @@ private slots:
     void OnTasStartStop();
     void OnTasRecord();
     void OnTasReset();
+    void OnToggleGraphicsAPI();
     void OnToggleDockedMode();
     void OnToggleGpuAccuracy();
     void OnToggleAdaptingFilter();
@@ -347,6 +348,7 @@ private:
     void UpdateWindowTitle(std::string_view title_name = {}, std::string_view title_version = {},
                            std::string_view gpu_vendor = {});
     void UpdateDockedButton();
+    void UpdateAPIText();
     void UpdateFilterText();
     void UpdateAAText();
     void UpdateStatusBar();

src/yuzu_cmd/CMakeLists.txt

@@ -22,6 +22,8 @@ add_executable(yuzu-cmd
     emu_window/emu_window_sdl2.h
     emu_window/emu_window_sdl2_gl.cpp
     emu_window/emu_window_sdl2_gl.h
+    emu_window/emu_window_sdl2_null.cpp
+    emu_window/emu_window_sdl2_null.h
     emu_window/emu_window_sdl2_vk.cpp
     emu_window/emu_window_sdl2_vk.h
     yuzu.cpp

src/yuzu_cmd/emu_window/emu_window_sdl2.h

@@ -89,3 +89,5 @@ protected:
     /// yuzu core instance
     Core::System& system;
 };
+
+class DummyContext : public Core::Frontend::GraphicsContext {};

src/yuzu_cmd/emu_window/emu_window_sdl2_null.cpp

@@ -0,0 +1,51 @@
+// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <cstdlib>
+#include <memory>
+#include <string>
+
+#include <fmt/format.h>
+
+#include "common/logging/log.h"
+#include "common/scm_rev.h"
+#include "video_core/renderer_null/renderer_null.h"
+#include "yuzu_cmd/emu_window/emu_window_sdl2_null.h"
+
+#ifdef YUZU_USE_EXTERNAL_SDL2
+// Include this before SDL.h to prevent the external from including a dummy
+#define USING_GENERATED_CONFIG_H
+#include <SDL_config.h>
+#endif
+
+#include <SDL.h>
+
+EmuWindow_SDL2_Null::EmuWindow_SDL2_Null(InputCommon::InputSubsystem* input_subsystem_,
+                                         Core::System& system_, bool fullscreen)
+    : EmuWindow_SDL2{input_subsystem_, system_} {
+    const std::string window_title = fmt::format("yuzu {} | {}-{} (Vulkan)", Common::g_build_name,
+                                                 Common::g_scm_branch, Common::g_scm_desc);
+    render_window =
+        SDL_CreateWindow(window_title.c_str(), SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
+                         Layout::ScreenUndocked::Width, Layout::ScreenUndocked::Height,
+                         SDL_WINDOW_RESIZABLE | SDL_WINDOW_ALLOW_HIGHDPI);
+
+    SetWindowIcon();
+
+    if (fullscreen) {
+        Fullscreen();
+        ShowCursor(false);
+    }
+
+    OnResize();
+    OnMinimalClientAreaChangeRequest(GetActiveConfig().min_client_area_size);
+    SDL_PumpEvents();
+    LOG_INFO(Frontend, "yuzu Version: {} | {}-{} (Null)", Common::g_build_name,
+             Common::g_scm_branch, Common::g_scm_desc);
+}
+
+EmuWindow_SDL2_Null::~EmuWindow_SDL2_Null() = default;
+
+std::unique_ptr<Core::Frontend::GraphicsContext> EmuWindow_SDL2_Null::CreateSharedContext() const {
+    return std::make_unique<DummyContext>();
+}

src/yuzu_cmd/emu_window/emu_window_sdl2_null.h

@@ -0,0 +1,26 @@
+// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <memory>
+
+#include "core/frontend/emu_window.h"
+#include "yuzu_cmd/emu_window/emu_window_sdl2.h"
+
+namespace Core {
+class System;
+}
+
+namespace InputCommon {
+class InputSubsystem;
+}
+
+class EmuWindow_SDL2_Null final : public EmuWindow_SDL2 {
+public:
+    explicit EmuWindow_SDL2_Null(InputCommon::InputSubsystem* input_subsystem_,
+                                 Core::System& system, bool fullscreen);
+    ~EmuWindow_SDL2_Null() override;
+
+    std::unique_ptr<Core::Frontend::GraphicsContext> CreateSharedContext() const override;
+};

src/yuzu_cmd/emu_window/emu_window_sdl2_vk.h

@@ -24,5 +24,3 @@ public:
 
     std::unique_ptr<Core::Frontend::GraphicsContext> CreateSharedContext() const override;
 };
-
-class DummyContext : public Core::Frontend::GraphicsContext {};

src/yuzu_cmd/yuzu.cpp

@@ -34,6 +34,7 @@
 #include "yuzu_cmd/config.h"
 #include "yuzu_cmd/emu_window/emu_window_sdl2.h"
 #include "yuzu_cmd/emu_window/emu_window_sdl2_gl.h"
+#include "yuzu_cmd/emu_window/emu_window_sdl2_null.h"
 #include "yuzu_cmd/emu_window/emu_window_sdl2_vk.h"
 
 #ifdef _WIN32
@@ -317,6 +318,9 @@ int main(int argc, char** argv) {
     case Settings::RendererBackend::Vulkan:
         emu_window = std::make_unique<EmuWindow_SDL2_VK>(&input_subsystem, system, fullscreen);
         break;
+    case Settings::RendererBackend::Null:
+        emu_window = std::make_unique<EmuWindow_SDL2_Null>(&input_subsystem, system, fullscreen);
+        break;
     }
 
     system.SetContentProvider(std::make_unique<FileSys::ContentProviderUnion>());