early-access version 1255

src/core/frontend/applets/controller.cpp

@@ -0,0 +1,81 @@
+// Copyright 2020 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include "common/assert.h"
+#include "common/logging/log.h"
+#include "core/frontend/applets/controller.h"
+#include "core/hle/service/hid/controllers/npad.h"
+#include "core/hle/service/hid/hid.h"
+#include "core/hle/service/sm/sm.h"
+
+namespace Core::Frontend {
+
+ControllerApplet::~ControllerApplet() = default;
+
+DefaultControllerApplet::DefaultControllerApplet(Service::SM::ServiceManager& service_manager_)
+    : service_manager{service_manager_} {}
+
+DefaultControllerApplet::~DefaultControllerApplet() = default;
+
+void DefaultControllerApplet::ReconfigureControllers(std::function<void()> callback,
+                                                     const ControllerParameters& parameters) const {
+    LOG_INFO(Service_HID, "called, deducing the best configuration based on the given parameters!");
+
+    auto& npad =
+        service_manager.GetService<Service::HID::Hid>("hid")
+            ->GetAppletResource()
+            ->GetController<Service::HID::Controller_NPad>(Service::HID::HidController::NPad);
+
+    auto& players = Settings::values.players.GetValue();
+
+    const std::size_t min_supported_players =
+        parameters.enable_single_mode ? 1 : parameters.min_players;
+
+    // Disconnect Handheld first.
+    npad.DisconnectNpadAtIndex(8);
+
+    // Deduce the best configuration based on the input parameters.
+    for (std::size_t index = 0; index < players.size() - 2; ++index) {
+        // First, disconnect all controllers regardless of the value of keep_controllers_connected.
+        // This makes it easy to connect the desired controllers.
+        npad.DisconnectNpadAtIndex(index);
+
+        // Only connect the minimum number of required players.
+        if (index >= min_supported_players) {
+            continue;
+        }
+
+        // Connect controllers based on the following priority list from highest to lowest priority:
+        // Pro Controller -> Dual Joycons -> Left Joycon/Right Joycon -> Handheld
+        if (parameters.allow_pro_controller) {
+            npad.AddNewControllerAt(
+                npad.MapSettingsTypeToNPad(Settings::ControllerType::ProController), index);
+        } else if (parameters.allow_dual_joycons) {
+            npad.AddNewControllerAt(
+                npad.MapSettingsTypeToNPad(Settings::ControllerType::DualJoyconDetached), index);
+        } else if (parameters.allow_left_joycon && parameters.allow_right_joycon) {
+            // Assign left joycons to even player indices and right joycons to odd player indices.
+            // We do this since Captain Toad Treasure Tracker expects a left joycon for Player 1 and
+            // a right Joycon for Player 2 in 2 Player Assist mode.
+            if (index % 2 == 0) {
+                npad.AddNewControllerAt(
+                    npad.MapSettingsTypeToNPad(Settings::ControllerType::LeftJoycon), index);
+            } else {
+                npad.AddNewControllerAt(
+                    npad.MapSettingsTypeToNPad(Settings::ControllerType::RightJoycon), index);
+            }
+        } else if (index == 0 && parameters.enable_single_mode && parameters.allow_handheld &&
+                   !Settings::values.use_docked_mode.GetValue()) {
+            // We should *never* reach here under any normal circumstances.
+            npad.AddNewControllerAt(npad.MapSettingsTypeToNPad(Settings::ControllerType::Handheld),
+                                    index);
+        } else {
+            UNREACHABLE_MSG("Unable to add a new controller based on the given parameters!");
+        }
+    }
+
+    callback();
+}
+
+} // namespace Core::Frontend

src/core/frontend/applets/controller.h

@@ -0,0 +1,56 @@
+// Copyright 2020 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <functional>
+
+#include "common/common_types.h"
+
+namespace Service::SM {
+class ServiceManager;
+}
+
+namespace Core::Frontend {
+
+using BorderColor = std::array<u8, 4>;
+using ExplainText = std::array<char, 0x81>;
+
+struct ControllerParameters {
+    s8 min_players{};
+    s8 max_players{};
+    bool keep_controllers_connected{};
+    bool enable_single_mode{};
+    bool enable_border_color{};
+    std::vector<BorderColor> border_colors{};
+    bool enable_explain_text{};
+    std::vector<ExplainText> explain_text{};
+    bool allow_pro_controller{};
+    bool allow_handheld{};
+    bool allow_dual_joycons{};
+    bool allow_left_joycon{};
+    bool allow_right_joycon{};
+};
+
+class ControllerApplet {
+public:
+    virtual ~ControllerApplet();
+
+    virtual void ReconfigureControllers(std::function<void()> callback,
+                                        const ControllerParameters& parameters) const = 0;
+};
+
+class DefaultControllerApplet final : public ControllerApplet {
+public:
+    explicit DefaultControllerApplet(Service::SM::ServiceManager& service_manager_);
+    ~DefaultControllerApplet() override;
+
+    void ReconfigureControllers(std::function<void()> callback,
+                                const ControllerParameters& parameters) const override;
+
+private:
+    Service::SM::ServiceManager& service_manager;
+};
+
+} // namespace Core::Frontend

src/core/frontend/applets/error.cpp

@@ -0,0 +1,35 @@
+// Copyright 2019 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include "common/logging/log.h"
+#include "core/frontend/applets/error.h"
+
+namespace Core::Frontend {
+
+ErrorApplet::~ErrorApplet() = default;
+
+void DefaultErrorApplet::ShowError(ResultCode error, std::function<void()> finished) const {
+    LOG_CRITICAL(Service_Fatal, "Application requested error display: {:04}-{:04} (raw={:08X})",
+                 error.module.Value(), error.description.Value(), error.raw);
+}
+
+void DefaultErrorApplet::ShowErrorWithTimestamp(ResultCode error, std::chrono::seconds time,
+                                                std::function<void()> finished) const {
+    LOG_CRITICAL(
+        Service_Fatal,
+        "Application requested error display: {:04X}-{:04X} (raw={:08X}) with timestamp={:016X}",
+        error.module.Value(), error.description.Value(), error.raw, time.count());
+}
+
+void DefaultErrorApplet::ShowCustomErrorText(ResultCode error, std::string main_text,
+                                             std::string detail_text,
+                                             std::function<void()> finished) const {
+    LOG_CRITICAL(Service_Fatal,
+                 "Application requested custom error with error_code={:04X}-{:04X} (raw={:08X})",
+                 error.module.Value(), error.description.Value(), error.raw);
+    LOG_CRITICAL(Service_Fatal, "    Main Text: {}", main_text);
+    LOG_CRITICAL(Service_Fatal, "    Detail Text: {}", detail_text);
+}
+
+} // namespace Core::Frontend

src/core/frontend/applets/error.h

@@ -0,0 +1,37 @@
+// Copyright 2019 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <chrono>
+#include <functional>
+
+#include "core/hle/result.h"
+
+namespace Core::Frontend {
+
+class ErrorApplet {
+public:
+    virtual ~ErrorApplet();
+
+    virtual void ShowError(ResultCode error, std::function<void()> finished) const = 0;
+
+    virtual void ShowErrorWithTimestamp(ResultCode error, std::chrono::seconds time,
+                                        std::function<void()> finished) const = 0;
+
+    virtual void ShowCustomErrorText(ResultCode error, std::string dialog_text,
+                                     std::string fullscreen_text,
+                                     std::function<void()> finished) const = 0;
+};
+
+class DefaultErrorApplet final : public ErrorApplet {
+public:
+    void ShowError(ResultCode error, std::function<void()> finished) const override;
+    void ShowErrorWithTimestamp(ResultCode error, std::chrono::seconds time,
+                                std::function<void()> finished) const override;
+    void ShowCustomErrorText(ResultCode error, std::string main_text, std::string detail_text,
+                             std::function<void()> finished) const override;
+};
+
+} // namespace Core::Frontend

src/core/frontend/applets/general_frontend.cpp

@@ -0,0 +1,56 @@
+// Copyright 2019 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include "common/logging/log.h"
+#include "core/frontend/applets/general_frontend.h"
+
+namespace Core::Frontend {
+
+ParentalControlsApplet::~ParentalControlsApplet() = default;
+
+DefaultParentalControlsApplet::~DefaultParentalControlsApplet() = default;
+
+void DefaultParentalControlsApplet::VerifyPIN(std::function<void(bool)> finished,
+                                              bool suspend_future_verification_temporarily) {
+    LOG_INFO(Service_AM,
+             "Application requested frontend to verify PIN (normal), "
+             "suspend_future_verification_temporarily={}, verifying as correct.",
+             suspend_future_verification_temporarily);
+    finished(true);
+}
+
+void DefaultParentalControlsApplet::VerifyPINForSettings(std::function<void(bool)> finished) {
+    LOG_INFO(Service_AM,
+             "Application requested frontend to verify PIN (settings), verifying as correct.");
+    finished(true);
+}
+
+void DefaultParentalControlsApplet::RegisterPIN(std::function<void()> finished) {
+    LOG_INFO(Service_AM, "Application requested frontend to register new PIN");
+    finished();
+}
+
+void DefaultParentalControlsApplet::ChangePIN(std::function<void()> finished) {
+    LOG_INFO(Service_AM, "Application requested frontend to change PIN to new value");
+    finished();
+}
+
+PhotoViewerApplet::~PhotoViewerApplet() = default;
+
+DefaultPhotoViewerApplet::~DefaultPhotoViewerApplet() = default;
+
+void DefaultPhotoViewerApplet::ShowPhotosForApplication(u64 title_id,
+                                                        std::function<void()> finished) const {
+    LOG_INFO(Service_AM,
+             "Application requested frontend to display stored photos for title_id={:016X}",
+             title_id);
+    finished();
+}
+
+void DefaultPhotoViewerApplet::ShowAllPhotos(std::function<void()> finished) const {
+    LOG_INFO(Service_AM, "Application requested frontend to display all stored photos.");
+    finished();
+}
+
+} // namespace Core::Frontend

src/core/frontend/applets/general_frontend.h

@@ -0,0 +1,61 @@
+// Copyright 2019 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <functional>
+#include <optional>
+#include "common/common_types.h"
+
+namespace Core::Frontend {
+
+class ParentalControlsApplet {
+public:
+    virtual ~ParentalControlsApplet();
+
+    // Prompts the user to enter a PIN and calls the callback with whether or not it matches the
+    // correct PIN. If the bool is passed, and the PIN was recently entered correctly, the frontend
+    // should not prompt and simply return true.
+    virtual void VerifyPIN(std::function<void(bool)> finished,
+                           bool suspend_future_verification_temporarily) = 0;
+
+    // Prompts the user to enter a PIN and calls the callback for correctness. Frontends can
+    // optionally alert the user that this is to change parental controls settings.
+    virtual void VerifyPINForSettings(std::function<void(bool)> finished) = 0;
+
+    // Prompts the user to create a new PIN for pctl and stores it with the service.
+    virtual void RegisterPIN(std::function<void()> finished) = 0;
+
+    // Prompts the user to verify the current PIN and then store a new one into pctl.
+    virtual void ChangePIN(std::function<void()> finished) = 0;
+};
+
+class DefaultParentalControlsApplet final : public ParentalControlsApplet {
+public:
+    ~DefaultParentalControlsApplet() override;
+
+    void VerifyPIN(std::function<void(bool)> finished,
+                   bool suspend_future_verification_temporarily) override;
+    void VerifyPINForSettings(std::function<void(bool)> finished) override;
+    void RegisterPIN(std::function<void()> finished) override;
+    void ChangePIN(std::function<void()> finished) override;
+};
+
+class PhotoViewerApplet {
+public:
+    virtual ~PhotoViewerApplet();
+
+    virtual void ShowPhotosForApplication(u64 title_id, std::function<void()> finished) const = 0;
+    virtual void ShowAllPhotos(std::function<void()> finished) const = 0;
+};
+
+class DefaultPhotoViewerApplet final : public PhotoViewerApplet {
+public:
+    ~DefaultPhotoViewerApplet() override;
+
+    void ShowPhotosForApplication(u64 title_id, std::function<void()> finished) const override;
+    void ShowAllPhotos(std::function<void()> finished) const override;
+};
+
+} // namespace Core::Frontend

src/core/frontend/applets/profile_select.cpp

@@ -0,0 +1,20 @@
+// Copyright 2018 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include "core/frontend/applets/profile_select.h"
+#include "core/hle/service/acc/profile_manager.h"
+#include "core/settings.h"
+
+namespace Core::Frontend {
+
+ProfileSelectApplet::~ProfileSelectApplet() = default;
+
+void DefaultProfileSelectApplet::SelectProfile(
+    std::function<void(std::optional<Common::UUID>)> callback) const {
+    Service::Account::ProfileManager manager;
+    callback(manager.GetUser(Settings::values.current_user).value_or(Common::UUID{}));
+    LOG_INFO(Service_ACC, "called, selecting current user instead of prompting...");
+}
+
+} // namespace Core::Frontend

src/core/frontend/applets/profile_select.h

@@ -0,0 +1,25 @@
+// Copyright 2018 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <functional>
+#include <optional>
+#include "common/uuid.h"
+
+namespace Core::Frontend {
+
+class ProfileSelectApplet {
+public:
+    virtual ~ProfileSelectApplet();
+
+    virtual void SelectProfile(std::function<void(std::optional<Common::UUID>)> callback) const = 0;
+};
+
+class DefaultProfileSelectApplet final : public ProfileSelectApplet {
+public:
+    void SelectProfile(std::function<void(std::optional<Common::UUID>)> callback) const override;
+};
+
+} // namespace Core::Frontend

src/core/frontend/applets/software_keyboard.cpp

@@ -0,0 +1,29 @@
+// Copyright 2018 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include "common/logging/backend.h"
+#include "common/string_util.h"
+#include "core/frontend/applets/software_keyboard.h"
+
+namespace Core::Frontend {
+SoftwareKeyboardApplet::~SoftwareKeyboardApplet() = default;
+
+void DefaultSoftwareKeyboardApplet::RequestText(
+    std::function<void(std::optional<std::u16string>)> out,
+    SoftwareKeyboardParameters parameters) const {
+    if (parameters.initial_text.empty())
+        out(u"yuzu");
+
+    out(parameters.initial_text);
+}
+
+void DefaultSoftwareKeyboardApplet::SendTextCheckDialog(
+    std::u16string error_message, std::function<void()> finished_check) const {
+    LOG_WARNING(Service_AM,
+                "(STUBBED) called - Default fallback software keyboard does not support text "
+                "check! (error_message={})",
+                Common::UTF16ToUTF8(error_message));
+    finished_check();
+}
+} // namespace Core::Frontend

src/core/frontend/applets/software_keyboard.h

@@ -0,0 +1,54 @@
+// Copyright 2018 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <functional>
+#include <optional>
+#include <string>
+#include "common/bit_field.h"
+#include "common/common_types.h"
+
+namespace Core::Frontend {
+struct SoftwareKeyboardParameters {
+    std::u16string submit_text;
+    std::u16string header_text;
+    std::u16string sub_text;
+    std::u16string guide_text;
+    std::u16string initial_text;
+    std::size_t max_length;
+    bool password;
+    bool cursor_at_beginning;
+
+    union {
+        u8 value;
+
+        BitField<1, 1, u8> disable_space;
+        BitField<2, 1, u8> disable_address;
+        BitField<3, 1, u8> disable_percent;
+        BitField<4, 1, u8> disable_slash;
+        BitField<6, 1, u8> disable_number;
+        BitField<7, 1, u8> disable_download_code;
+    };
+};
+
+class SoftwareKeyboardApplet {
+public:
+    virtual ~SoftwareKeyboardApplet();
+
+    virtual void RequestText(std::function<void(std::optional<std::u16string>)> out,
+                             SoftwareKeyboardParameters parameters) const = 0;
+    virtual void SendTextCheckDialog(std::u16string error_message,
+                                     std::function<void()> finished_check) const = 0;
+};
+
+class DefaultSoftwareKeyboardApplet final : public SoftwareKeyboardApplet {
+public:
+    void RequestText(std::function<void(std::optional<std::u16string>)> out,
+                     SoftwareKeyboardParameters parameters) const override;
+    void SendTextCheckDialog(std::u16string error_message,
+                             std::function<void()> finished_check) const override;
+};
+
+} // namespace Core::Frontend

src/core/frontend/applets/web_browser.cpp

@@ -0,0 +1,32 @@
+// Copyright 2018 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include "common/logging/log.h"
+#include "core/frontend/applets/web_browser.h"
+
+namespace Core::Frontend {
+
+WebBrowserApplet::~WebBrowserApplet() = default;
+
+DefaultWebBrowserApplet::~DefaultWebBrowserApplet() = default;
+
+void DefaultWebBrowserApplet::OpenLocalWebPage(
+    std::string_view local_url, std::function<void()> extract_romfs_callback,
+    std::function<void(Service::AM::Applets::WebExitReason, std::string)> callback) const {
+    LOG_WARNING(Service_AM, "(STUBBED) called, backend requested to open local web page at {}",
+                local_url);
+
+    callback(Service::AM::Applets::WebExitReason::WindowClosed, "http://localhost/");
+}
+
+void DefaultWebBrowserApplet::OpenExternalWebPage(
+    std::string_view external_url,
+    std::function<void(Service::AM::Applets::WebExitReason, std::string)> callback) const {
+    LOG_WARNING(Service_AM, "(STUBBED) called, backend requested to open external web page at {}",
+                external_url);
+
+    callback(Service::AM::Applets::WebExitReason::WindowClosed, "http://localhost/");
+}
+
+} // namespace Core::Frontend

src/core/frontend/applets/web_browser.h

@@ -0,0 +1,40 @@
+// Copyright 2018 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <functional>
+#include <string_view>
+
+#include "core/hle/service/am/applets/web_types.h"
+
+namespace Core::Frontend {
+
+class WebBrowserApplet {
+public:
+    virtual ~WebBrowserApplet();
+
+    virtual void OpenLocalWebPage(
+        std::string_view local_url, std::function<void()> extract_romfs_callback,
+        std::function<void(Service::AM::Applets::WebExitReason, std::string)> callback) const = 0;
+
+    virtual void OpenExternalWebPage(
+        std::string_view external_url,
+        std::function<void(Service::AM::Applets::WebExitReason, std::string)> callback) const = 0;
+};
+
+class DefaultWebBrowserApplet final : public WebBrowserApplet {
+public:
+    ~DefaultWebBrowserApplet() override;
+
+    void OpenLocalWebPage(std::string_view local_url, std::function<void()> extract_romfs_callback,
+                          std::function<void(Service::AM::Applets::WebExitReason, std::string)>
+                              callback) const override;
+
+    void OpenExternalWebPage(std::string_view external_url,
+                             std::function<void(Service::AM::Applets::WebExitReason, std::string)>
+                                 callback) const override;
+};
+
+} // namespace Core::Frontend

src/core/frontend/emu_window.cpp

@@ -0,0 +1,118 @@
+// Copyright 2014 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <cmath>
+#include <mutex>
+#include "core/frontend/emu_window.h"
+#include "core/frontend/input.h"
+#include "core/settings.h"
+
+namespace Core::Frontend {
+
+GraphicsContext::~GraphicsContext() = default;
+
+class EmuWindow::TouchState : public Input::Factory<Input::TouchDevice>,
+                              public std::enable_shared_from_this<TouchState> {
+public:
+    std::unique_ptr<Input::TouchDevice> Create(const Common::ParamPackage&) override {
+        return std::make_unique<Device>(shared_from_this());
+    }
+
+    std::mutex mutex;
+
+    bool touch_pressed = false; ///< True if touchpad area is currently pressed, otherwise false
+
+    float touch_x = 0.0f; ///< Touchpad X-position
+    float touch_y = 0.0f; ///< Touchpad Y-position
+
+private:
+    class Device : public Input::TouchDevice {
+    public:
+        explicit Device(std::weak_ptr<TouchState>&& touch_state) : touch_state(touch_state) {}
+        std::tuple<float, float, bool> GetStatus() const override {
+            if (auto state = touch_state.lock()) {
+                std::lock_guard guard{state->mutex};
+                return std::make_tuple(state->touch_x, state->touch_y, state->touch_pressed);
+            }
+            return std::make_tuple(0.0f, 0.0f, false);
+        }
+
+    private:
+        std::weak_ptr<TouchState> touch_state;
+    };
+};
+
+EmuWindow::EmuWindow() {
+    // TODO: Find a better place to set this.
+    config.min_client_area_size =
+        std::make_pair(Layout::MinimumSize::Width, Layout::MinimumSize::Height);
+    active_config = config;
+    touch_state = std::make_shared<TouchState>();
+    Input::RegisterFactory<Input::TouchDevice>("emu_window", touch_state);
+}
+
+EmuWindow::~EmuWindow() {
+    Input::UnregisterFactory<Input::TouchDevice>("emu_window");
+}
+
+/**
+ * Check if the given x/y coordinates are within the touchpad specified by the framebuffer layout
+ * @param layout FramebufferLayout object describing the framebuffer size and screen positions
+ * @param framebuffer_x Framebuffer x-coordinate to check
+ * @param framebuffer_y Framebuffer y-coordinate to check
+ * @return True if the coordinates are within the touchpad, otherwise false
+ */
+static bool IsWithinTouchscreen(const Layout::FramebufferLayout& layout, unsigned framebuffer_x,
+                                unsigned framebuffer_y) {
+    return (framebuffer_y >= layout.screen.top && framebuffer_y < layout.screen.bottom &&
+            framebuffer_x >= layout.screen.left && framebuffer_x < layout.screen.right);
+}
+
+std::tuple<unsigned, unsigned> EmuWindow::ClipToTouchScreen(unsigned new_x, unsigned new_y) const {
+    new_x = std::max(new_x, framebuffer_layout.screen.left);
+    new_x = std::min(new_x, framebuffer_layout.screen.right - 1);
+
+    new_y = std::max(new_y, framebuffer_layout.screen.top);
+    new_y = std::min(new_y, framebuffer_layout.screen.bottom - 1);
+
+    return std::make_tuple(new_x, new_y);
+}
+
+void EmuWindow::TouchPressed(unsigned framebuffer_x, unsigned framebuffer_y) {
+    if (!IsWithinTouchscreen(framebuffer_layout, framebuffer_x, framebuffer_y))
+        return;
+
+    std::lock_guard guard{touch_state->mutex};
+    touch_state->touch_x =
+        static_cast<float>(framebuffer_x - framebuffer_layout.screen.left) /
+        static_cast<float>(framebuffer_layout.screen.right - framebuffer_layout.screen.left);
+    touch_state->touch_y =
+        static_cast<float>(framebuffer_y - framebuffer_layout.screen.top) /
+        static_cast<float>(framebuffer_layout.screen.bottom - framebuffer_layout.screen.top);
+
+    touch_state->touch_pressed = true;
+}
+
+void EmuWindow::TouchReleased() {
+    std::lock_guard guard{touch_state->mutex};
+    touch_state->touch_pressed = false;
+    touch_state->touch_x = 0;
+    touch_state->touch_y = 0;
+}
+
+void EmuWindow::TouchMoved(unsigned framebuffer_x, unsigned framebuffer_y) {
+    if (!touch_state->touch_pressed)
+        return;
+
+    if (!IsWithinTouchscreen(framebuffer_layout, framebuffer_x, framebuffer_y))
+        std::tie(framebuffer_x, framebuffer_y) = ClipToTouchScreen(framebuffer_x, framebuffer_y);
+
+    TouchPressed(framebuffer_x, framebuffer_y);
+}
+
+void EmuWindow::UpdateCurrentFramebufferLayout(unsigned width, unsigned height) {
+    NotifyFramebufferLayoutChanged(Layout::DefaultFrameLayout(width, height));
+}
+
+} // namespace Core::Frontend

src/core/frontend/emu_window.h

@@ -0,0 +1,241 @@
+// Copyright 2014 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <memory>
+#include <tuple>
+#include <utility>
+#include "common/common_types.h"
+#include "core/frontend/framebuffer_layout.h"
+
+namespace Core::Frontend {
+
+/// Information for the Graphics Backends signifying what type of screen pointer is in
+/// WindowInformation
+enum class WindowSystemType {
+    Headless,
+    Windows,
+    X11,
+    Wayland,
+};
+
+/**
+ * Represents a drawing context that supports graphics operations.
+ */
+class GraphicsContext {
+public:
+    virtual ~GraphicsContext();
+
+    /// Inform the driver to swap the front/back buffers and present the current image
+    virtual void SwapBuffers() {}
+
+    /// Makes the graphics context current for the caller thread
+    virtual void MakeCurrent() {}
+
+    /// Releases (dunno if this is the "right" word) the context from the caller thread
+    virtual void DoneCurrent() {}
+
+    class Scoped {
+    public:
+        [[nodiscard]] explicit Scoped(GraphicsContext& context_) : context(context_) {
+            context.MakeCurrent();
+        }
+        ~Scoped() {
+            context.DoneCurrent();
+        }
+
+    private:
+        GraphicsContext& context;
+    };
+
+    /// Calls MakeCurrent on the context and calls DoneCurrent when the scope for the returned value
+    /// ends
+    [[nodiscard]] Scoped Acquire() {
+        return Scoped{*this};
+    }
+};
+
+/**
+ * Abstraction class used to provide an interface between emulation code and the frontend
+ * (e.g. SDL, QGLWidget, GLFW, etc...).
+ *
+ * Design notes on the interaction between EmuWindow and the emulation core:
+ * - Generally, decisions on anything visible to the user should be left up to the GUI.
+ *   For example, the emulation core should not try to dictate some window title or size.
+ *   This stuff is not the core's business and only causes problems with regards to thread-safety
+ *   anyway.
+ * - Under certain circumstances, it may be desirable for the core to politely request the GUI
+ *   to set e.g. a minimum window size. However, the GUI should always be free to ignore any
+ *   such hints.
+ * - EmuWindow may expose some of its state as read-only to the emulation core, however care
+ *   should be taken to make sure the provided information is self-consistent. This requires
+ *   some sort of synchronization (most of this is still a TODO).
+ * - DO NOT TREAT THIS CLASS AS A GUI TOOLKIT ABSTRACTION LAYER. That's not what it is. Please
+ *   re-read the upper points again and think about it if you don't see this.
+ */
+class EmuWindow {
+public:
+    /// Data structure to store emuwindow configuration
+    struct WindowConfig {
+        bool fullscreen = false;
+        int res_width = 0;
+        int res_height = 0;
+        std::pair<unsigned, unsigned> min_client_area_size;
+    };
+
+    /// Data describing host window system information
+    struct WindowSystemInfo {
+        // Window system type. Determines which GL context or Vulkan WSI is used.
+        WindowSystemType type = WindowSystemType::Headless;
+
+        // Connection to a display server. This is used on X11 and Wayland platforms.
+        void* display_connection = nullptr;
+
+        // Render surface. This is a pointer to the native window handle, which depends
+        // on the platform. e.g. HWND for Windows, Window for X11. If the surface is
+        // set to nullptr, the video backend will run in headless mode.
+        void* render_surface = nullptr;
+
+        // Scale of the render surface. For hidpi systems, this will be >1.
+        float render_surface_scale = 1.0f;
+    };
+
+    /// Called from GPU thread when a frame is displayed.
+    virtual void OnFrameDisplayed() {}
+
+    /**
+     * Returns a GraphicsContext that the frontend provides to be used for rendering.
+     */
+    virtual std::unique_ptr<GraphicsContext> CreateSharedContext() const = 0;
+
+    /// Returns if window is shown (not minimized)
+    virtual bool IsShown() const = 0;
+
+    /**
+     * Signal that a touch pressed event has occurred (e.g. mouse click pressed)
+     * @param framebuffer_x Framebuffer x-coordinate that was pressed
+     * @param framebuffer_y Framebuffer y-coordinate that was pressed
+     */
+    void TouchPressed(unsigned framebuffer_x, unsigned framebuffer_y);
+
+    /// Signal that a touch released event has occurred (e.g. mouse click released)
+    void TouchReleased();
+
+    /**
+     * Signal that a touch movement event has occurred (e.g. mouse was moved over the emu window)
+     * @param framebuffer_x Framebuffer x-coordinate
+     * @param framebuffer_y Framebuffer y-coordinate
+     */
+    void TouchMoved(unsigned framebuffer_x, unsigned framebuffer_y);
+
+    /**
+     * Returns currently active configuration.
+     * @note Accesses to the returned object need not be consistent because it may be modified in
+     * another thread
+     */
+    const WindowConfig& GetActiveConfig() const {
+        return active_config;
+    }
+
+    /**
+     * Requests the internal configuration to be replaced by the specified argument at some point in
+     * the future.
+     * @note This method is thread-safe, because it delays configuration changes to the GUI event
+     * loop. Hence there is no guarantee on when the requested configuration will be active.
+     */
+    void SetConfig(const WindowConfig& val) {
+        config = val;
+    }
+
+    /**
+     * Returns system information about the drawing area.
+     */
+    const WindowSystemInfo& GetWindowInfo() const {
+        return window_info;
+    }
+
+    /**
+     * Gets the framebuffer layout (width, height, and screen regions)
+     * @note This method is thread-safe
+     */
+    const Layout::FramebufferLayout& GetFramebufferLayout() const {
+        return framebuffer_layout;
+    }
+
+    /**
+     * Convenience method to update the current frame layout
+     * Read from the current settings to determine which layout to use.
+     */
+    void UpdateCurrentFramebufferLayout(unsigned width, unsigned height);
+
+protected:
+    explicit EmuWindow();
+    virtual ~EmuWindow();
+
+    /**
+     * Processes any pending configuration changes from the last SetConfig call.
+     * This method invokes OnMinimalClientAreaChangeRequest if the corresponding configuration
+     * field changed.
+     * @note Implementations will usually want to call this from the GUI thread.
+     * @todo Actually call this in existing implementations.
+     */
+    void ProcessConfigurationChanges() {
+        // TODO: For proper thread safety, we should eventually implement a proper
+        // multiple-writer/single-reader queue...
+
+        if (config.min_client_area_size != active_config.min_client_area_size) {
+            OnMinimalClientAreaChangeRequest(config.min_client_area_size);
+            config.min_client_area_size = active_config.min_client_area_size;
+        }
+    }
+
+    /**
+     * Update framebuffer layout with the given parameter.
+     * @note EmuWindow implementations will usually use this in window resize event handlers.
+     */
+    void NotifyFramebufferLayoutChanged(const Layout::FramebufferLayout& layout) {
+        framebuffer_layout = layout;
+    }
+
+    /**
+     * Update internal client area size with the given parameter.
+     * @note EmuWindow implementations will usually use this in window resize event handlers.
+     */
+    void NotifyClientAreaSizeChanged(const std::pair<unsigned, unsigned>& size) {
+        client_area_width = size.first;
+        client_area_height = size.second;
+    }
+
+    WindowSystemInfo window_info;
+
+private:
+    /**
+     * Handler called when the minimal client area was requested to be changed via SetConfig.
+     * For the request to be honored, EmuWindow implementations will usually reimplement this
+     * function.
+     */
+    virtual void OnMinimalClientAreaChangeRequest(std::pair<unsigned, unsigned>) {
+        // By default, ignore this request and do nothing.
+    }
+
+    Layout::FramebufferLayout framebuffer_layout; ///< Current framebuffer layout
+
+    unsigned client_area_width;  ///< Current client width, should be set by window impl.
+    unsigned client_area_height; ///< Current client height, should be set by window impl.
+
+    WindowConfig config;        ///< Internal configuration (changes pending for being applied in
+                                /// ProcessConfigurationChanges)
+    WindowConfig active_config; ///< Internal active configuration
+
+    class TouchState;
+    std::shared_ptr<TouchState> touch_state;
+
+    /**
+     * Clip the provided coordinates to be inside the touchscreen area.
+     */
+    std::tuple<unsigned, unsigned> ClipToTouchScreen(unsigned new_x, unsigned new_y) const;
+};
+
+} // namespace Core::Frontend

src/core/frontend/framebuffer_layout.cpp

@@ -0,0 +1,76 @@
+// Copyright 2018 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <cmath>
+
+#include "common/assert.h"
+#include "core/frontend/framebuffer_layout.h"
+#include "core/settings.h"
+
+namespace Layout {
+
+// Finds the largest size subrectangle contained in window area that is confined to the aspect ratio
+template <class T>
+static Common::Rectangle<T> MaxRectangle(Common::Rectangle<T> window_area,
+                                         float screen_aspect_ratio) {
+    const float scale = std::min(static_cast<float>(window_area.GetWidth()),
+                                 static_cast<float>(window_area.GetHeight()) / screen_aspect_ratio);
+    return Common::Rectangle<T>{0, 0, static_cast<T>(std::round(scale)),
+                                static_cast<T>(std::round(scale * screen_aspect_ratio))};
+}
+
+FramebufferLayout DefaultFrameLayout(u32 width, u32 height) {
+    ASSERT(width > 0);
+    ASSERT(height > 0);
+    // The drawing code needs at least somewhat valid values for both screens
+    // so just calculate them both even if the other isn't showing.
+    FramebufferLayout res{width, height, false, {}};
+
+    const float window_aspect_ratio = static_cast<float>(height) / static_cast<float>(width);
+    const float emulation_aspect_ratio = EmulationAspectRatio(
+        static_cast<AspectRatio>(Settings::values.aspect_ratio.GetValue()), window_aspect_ratio);
+
+    const Common::Rectangle<u32> screen_window_area{0, 0, width, height};
+    Common::Rectangle<u32> screen = MaxRectangle(screen_window_area, emulation_aspect_ratio);
+
+    if (window_aspect_ratio < emulation_aspect_ratio) {
+        screen = screen.TranslateX((screen_window_area.GetWidth() - screen.GetWidth()) / 2);
+    } else {
+        screen = screen.TranslateY((height - screen.GetHeight()) / 2);
+    }
+
+    res.screen = screen;
+    return res;
+}
+
+FramebufferLayout FrameLayoutFromResolutionScale(u32 res_scale) {
+    u32 width, height;
+
+    if (Settings::values.use_docked_mode.GetValue()) {
+        width = ScreenDocked::Width * res_scale;
+        height = ScreenDocked::Height * res_scale;
+    } else {
+        width = ScreenUndocked::Width * res_scale;
+        height = ScreenUndocked::Height * res_scale;
+    }
+
+    return DefaultFrameLayout(width, height);
+}
+
+float EmulationAspectRatio(AspectRatio aspect, float window_aspect_ratio) {
+    switch (aspect) {
+    case AspectRatio::Default:
+        return static_cast<float>(ScreenUndocked::Height) / ScreenUndocked::Width;
+    case AspectRatio::R4_3:
+        return 3.0f / 4.0f;
+    case AspectRatio::R21_9:
+        return 9.0f / 21.0f;
+    case AspectRatio::StretchToWindow:
+        return window_aspect_ratio;
+    default:
+        return static_cast<float>(ScreenUndocked::Height) / ScreenUndocked::Width;
+    }
+}
+
+} // namespace Layout

src/core/frontend/framebuffer_layout.h

@@ -0,0 +1,73 @@
+// Copyright 2018 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include "common/common_types.h"
+#include "common/math_util.h"
+
+namespace Layout {
+
+namespace MinimumSize {
+constexpr u32 Width = 640;
+constexpr u32 Height = 360;
+} // namespace MinimumSize
+
+namespace ScreenUndocked {
+constexpr u32 Width = 1280;
+constexpr u32 Height = 720;
+} // namespace ScreenUndocked
+
+namespace ScreenDocked {
+constexpr u32 Width = 1920;
+constexpr u32 Height = 1080;
+} // namespace ScreenDocked
+
+enum class AspectRatio {
+    Default,
+    R4_3,
+    R21_9,
+    StretchToWindow,
+};
+
+/// Describes the layout of the window framebuffer
+struct FramebufferLayout {
+    u32 width{ScreenUndocked::Width};
+    u32 height{ScreenUndocked::Height};
+    bool is_srgb{};
+
+    Common::Rectangle<u32> screen;
+
+    /**
+     * Returns the ration of pixel size of the screen, compared to the native size of the undocked
+     * Switch screen.
+     */
+    float GetScalingRatio() const {
+        return static_cast<float>(screen.GetWidth()) / ScreenUndocked::Width;
+    }
+};
+
+/**
+ * Factory method for constructing a default FramebufferLayout
+ * @param width Window framebuffer width in pixels
+ * @param height Window framebuffer height in pixels
+ * @return Newly created FramebufferLayout object with default screen regions initialized
+ */
+FramebufferLayout DefaultFrameLayout(u32 width, u32 height);
+
+/**
+ * Convenience method to get frame layout by resolution scale
+ * @param res_scale resolution scale factor
+ */
+FramebufferLayout FrameLayoutFromResolutionScale(u32 res_scale);
+
+/**
+ * Convenience method to determine emulation aspect ratio
+ * @param aspect Represents the index of aspect ratio stored in Settings::values.aspect_ratio
+ * @param window_aspect_ratio Current window aspect ratio
+ * @return Emulation render window aspect ratio
+ */
+float EmulationAspectRatio(AspectRatio aspect, float window_aspect_ratio);
+
+} // namespace Layout

src/core/frontend/input.h

@@ -0,0 +1,183 @@
+// Copyright 2017 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <memory>
+#include <string>
+#include <tuple>
+#include <unordered_map>
+#include <utility>
+#include "common/logging/log.h"
+#include "common/param_package.h"
+#include "common/vector_math.h"
+
+namespace Input {
+
+enum class AnalogDirection : u8 {
+    RIGHT,
+    LEFT,
+    UP,
+    DOWN,
+};
+
+/// An abstract class template for an input device (a button, an analog input, etc.).
+template <typename StatusType>
+class InputDevice {
+public:
+    virtual ~InputDevice() = default;
+    virtual StatusType GetStatus() const {
+        return {};
+    }
+    virtual bool GetAnalogDirectionStatus([[maybe_unused]] AnalogDirection direction) const {
+        return {};
+    }
+    virtual bool SetRumblePlay([[maybe_unused]] f32 amp_low, [[maybe_unused]] f32 freq_low,
+                               [[maybe_unused]] f32 amp_high,
+                               [[maybe_unused]] f32 freq_high) const {
+        return {};
+    }
+};
+
+/// An abstract class template for a factory that can create input devices.
+template <typename InputDeviceType>
+class Factory {
+public:
+    virtual ~Factory() = default;
+    virtual std::unique_ptr<InputDeviceType> Create(const Common::ParamPackage&) = 0;
+};
+
+namespace Impl {
+
+template <typename InputDeviceType>
+using FactoryListType = std::unordered_map<std::string, std::shared_ptr<Factory<InputDeviceType>>>;
+
+template <typename InputDeviceType>
+struct FactoryList {
+    static FactoryListType<InputDeviceType> list;
+};
+
+template <typename InputDeviceType>
+FactoryListType<InputDeviceType> FactoryList<InputDeviceType>::list;
+
+} // namespace Impl
+
+/**
+ * Registers an input device factory.
+ * @tparam InputDeviceType the type of input devices the factory can create
+ * @param name the name of the factory. Will be used to match the "engine" parameter when creating
+ *     a device
+ * @param factory the factory object to register
+ */
+template <typename InputDeviceType>
+void RegisterFactory(const std::string& name, std::shared_ptr<Factory<InputDeviceType>> factory) {
+    auto pair = std::make_pair(name, std::move(factory));
+    if (!Impl::FactoryList<InputDeviceType>::list.insert(std::move(pair)).second) {
+        LOG_ERROR(Input, "Factory '{}' already registered", name);
+    }
+}
+
+/**
+ * Unregisters an input device factory.
+ * @tparam InputDeviceType the type of input devices the factory can create
+ * @param name the name of the factory to unregister
+ */
+template <typename InputDeviceType>
+void UnregisterFactory(const std::string& name) {
+    if (Impl::FactoryList<InputDeviceType>::list.erase(name) == 0) {
+        LOG_ERROR(Input, "Factory '{}' not registered", name);
+    }
+}
+
+/**
+ * Create an input device from given paramters.
+ * @tparam InputDeviceType the type of input devices to create
+ * @param params a serialized ParamPackage string contains all parameters for creating the device
+ */
+template <typename InputDeviceType>
+std::unique_ptr<InputDeviceType> CreateDevice(const std::string& params) {
+    const Common::ParamPackage package(params);
+    const std::string engine = package.Get("engine", "null");
+    const auto& factory_list = Impl::FactoryList<InputDeviceType>::list;
+    const auto pair = factory_list.find(engine);
+    if (pair == factory_list.end()) {
+        if (engine != "null") {
+            LOG_ERROR(Input, "Unknown engine name: {}", engine);
+        }
+        return std::make_unique<InputDeviceType>();
+    }
+    return pair->second->Create(package);
+}
+
+/**
+ * A button device is an input device that returns bool as status.
+ * true for pressed; false for released.
+ */
+using ButtonDevice = InputDevice<bool>;
+
+/**
+ * An analog device is an input device that returns a tuple of x and y coordinates as status. The
+ * coordinates are within the unit circle. x+ is defined as right direction, and y+ is defined as up
+ * direction
+ */
+using AnalogDevice = InputDevice<std::tuple<float, float>>;
+
+/**
+ * A vibration device is an input device that returns an unsigned byte as status.
+ * It represents whether the vibration device supports vibration or not.
+ * If the status returns 1, it supports vibration. Otherwise, it does not support vibration.
+ */
+using VibrationDevice = InputDevice<u8>;
+
+/**
+ * A motion status is an object that returns a tuple of accelerometer state vector,
+ * gyroscope state vector, rotation state vector and orientation state matrix.
+ *
+ * For both vectors:
+ *   x+ is the same direction as RIGHT on D-pad.
+ *   y+ is normal to the touch screen, pointing outward.
+ *   z+ is the same direction as UP on D-pad.
+ *
+ * For accelerometer state vector
+ *   Units: g (gravitational acceleration)
+ *
+ * For gyroscope state vector:
+ *   Orientation is determined by right-hand rule.
+ *   Units: deg/sec
+ *
+ * For rotation state vector
+ *   Units: rotations
+ *
+ * For orientation state matrix
+ *   x vector
+ *   y vector
+ *   z vector
+ */
+using MotionStatus = std::tuple<Common::Vec3<float>, Common::Vec3<float>, Common::Vec3<float>,
+                                std::array<Common::Vec3f, 3>>;
+
+/**
+ * A motion device is an input device that returns a motion status object
+ */
+using MotionDevice = InputDevice<MotionStatus>;
+
+/**
+ * A touch status is an object that returns a tuple of two floats and a bool. The floats are
+ * x and y coordinates in the range 0.0 - 1.0, and the bool indicates whether it is pressed.
+ */
+using TouchStatus = std::tuple<float, float, bool>;
+
+/**
+ * A touch device is an input device that returns a touch status object
+ */
+using TouchDevice = InputDevice<TouchStatus>;
+
+/**
+ * A mouse device is an input device that returns a tuple of two floats and four ints.
+ * The first two floats are X and Y device coordinates of the mouse (from 0-1).
+ * The s32s are the mouse wheel.
+ */
+using MouseDevice = InputDevice<std::tuple<float, float, s32, s32>>;
+
+} // namespace Input

src/core/frontend/input_interpreter.cpp

@@ -0,0 +1,45 @@
+// Copyright 2020 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include "core/core.h"
+#include "core/frontend/input_interpreter.h"
+#include "core/hle/service/hid/controllers/npad.h"
+#include "core/hle/service/hid/hid.h"
+#include "core/hle/service/sm/sm.h"
+
+InputInterpreter::InputInterpreter(Core::System& system)
+    : npad{system.ServiceManager()
+               .GetService<Service::HID::Hid>("hid")
+               ->GetAppletResource()
+               ->GetController<Service::HID::Controller_NPad>(Service::HID::HidController::NPad)} {}
+
+InputInterpreter::~InputInterpreter() = default;
+
+void InputInterpreter::PollInput() {
+    const u32 button_state = npad.GetAndResetPressState();
+
+    previous_index = current_index;
+    current_index = (current_index + 1) % button_states.size();
+
+    button_states[current_index] = button_state;
+}
+
+bool InputInterpreter::IsButtonPressedOnce(HIDButton button) const {
+    const bool current_press =
+        (button_states[current_index] & (1U << static_cast<u8>(button))) != 0;
+    const bool previous_press =
+        (button_states[previous_index] & (1U << static_cast<u8>(button))) != 0;
+
+    return current_press && !previous_press;
+}
+
+bool InputInterpreter::IsButtonHeld(HIDButton button) const {
+    u32 held_buttons{button_states[0]};
+
+    for (std::size_t i = 1; i < button_states.size(); ++i) {
+        held_buttons &= button_states[i];
+    }
+
+    return (held_buttons & (1U << static_cast<u8>(button))) != 0;
+}

src/core/frontend/input_interpreter.h

@@ -0,0 +1,120 @@
+// Copyright 2020 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <array>
+
+#include "common/common_types.h"
+
+namespace Core {
+class System;
+}
+
+namespace Service::HID {
+class Controller_NPad;
+}
+
+enum class HIDButton : u8 {
+    A,
+    B,
+    X,
+    Y,
+    LStick,
+    RStick,
+    L,
+    R,
+    ZL,
+    ZR,
+    Plus,
+    Minus,
+
+    DLeft,
+    DUp,
+    DRight,
+    DDown,
+
+    LStickLeft,
+    LStickUp,
+    LStickRight,
+    LStickDown,
+
+    RStickLeft,
+    RStickUp,
+    RStickRight,
+    RStickDown,
+
+    LeftSL,
+    LeftSR,
+
+    RightSL,
+    RightSR,
+};
+
+/**
+ * The InputInterpreter class interfaces with HID to retrieve button press states.
+ * Input is intended to be polled every 50ms so that a button is considered to be
+ * held down after 400ms has elapsed since the initial button press and subsequent
+ * repeated presses occur every 50ms.
+ */
+class InputInterpreter {
+public:
+    explicit InputInterpreter(Core::System& system);
+    virtual ~InputInterpreter();
+
+    /// Gets a button state from HID and inserts it into the array of button states.
+    void PollInput();
+
+    /**
+     * The specified button is considered to be pressed once
+     * if it is currently pressed and not pressed previously.
+     *
+     * @param button The button to check.
+     *
+     * @returns True when the button is pressed once.
+     */
+    [[nodiscard]] bool IsButtonPressedOnce(HIDButton button) const;
+
+    /**
+     * Checks whether any of the buttons in the parameter list is pressed once.
+     *
+     * @tparam HIDButton The buttons to check.
+     *
+     * @returns True when at least one of the buttons is pressed once.
+     */
+    template <HIDButton... T>
+    [[nodiscard]] bool IsAnyButtonPressedOnce() {
+        return (IsButtonPressedOnce(T) || ...);
+    }
+
+    /**
+     * The specified button is considered to be held down if it is pressed in all 9 button states.
+     *
+     * @param button The button to check.
+     *
+     * @returns True when the button is held down.
+     */
+    [[nodiscard]] bool IsButtonHeld(HIDButton button) const;
+
+    /**
+     * Checks whether any of the buttons in the parameter list is held down.
+     *
+     * @tparam HIDButton The buttons to check.
+     *
+     * @returns True when at least one of the buttons is held down.
+     */
+    template <HIDButton... T>
+    [[nodiscard]] bool IsAnyButtonHeld() {
+        return (IsButtonHeld(T) || ...);
+    }
+
+private:
+    Service::HID::Controller_NPad& npad;
+
+    /// Stores 9 consecutive button states polled from HID.
+    std::array<u32, 9> button_states{};
+
+    std::size_t previous_index{};
+    std::size_t current_index{};
+};