video_core: add null backend

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>());