Configurable keyboard mappings

include/mappings.hpp

@@ -0,0 +1,23 @@
+#pragma once
+
+#include <unordered_map>
+
+#include "helpers.hpp"
+#include "services/hid.hpp"
+
+struct InputMappings {
+	using Scancode = u32;
+	using Container = std::unordered_map<Scancode, u32>;
+
+	u32 getMapping(Scancode scancode) const {
+		auto it = container.find(scancode);
+		return it != container.end() ? it->second : HID::Keys::Null;
+	}
+
+	void setMapping(Scancode scancode, u32 key) { container[scancode] = key; }
+
+	static InputMappings DefaultKeyboardMappings();
+
+  private:
+	Container container;
+};

include/panda_qt/main_window.hpp

@@ -11,6 +11,7 @@
 #include <vector>
 
 #include "emulator.hpp"
+#include "mappings.hpp"
 #include "panda_qt/about_window.hpp"
 #include "panda_qt/config_window.hpp"
 #include "panda_qt/cheats_window.hpp"
@@ -80,6 +81,7 @@ class MainWindow : public QMainWindow {
 
 	// This would normally be an std::unique_ptr but it's shared between threads so definitely not
 	Emulator* emu = nullptr;
+	InputMappings keyboardMappings;
 	std::thread emuThread;
 
 	std::atomic<bool> appRunning = true;  // Is the application itself running?

include/panda_sdl/frontend_sdl.hpp

@@ -5,9 +5,11 @@
 #include <filesystem>
 
 #include "emulator.hpp"
+#include "mappings.hpp"
 
 class FrontendSDL {
 	Emulator emu;
+	InputMappings keyboardMappings;
 #ifdef PANDA3DS_ENABLE_OPENGL
 	SDL_GLContext glContext;
 #endif
@@ -16,6 +18,7 @@ class FrontendSDL {
 	FrontendSDL();
 	bool loadROM(const std::filesystem::path& path);
 	void run();
+	u32 getMapping(InputMappings::Scancode scancode) { return keyboardMappings.getMapping(scancode); }
 
 	SDL_Window* window = nullptr;
 	SDL_GameController* gameController = nullptr;

include/services/hid.hpp

@@ -10,6 +10,7 @@
 
 namespace HID::Keys {
 	enum : u32 {
+		Null = 0,
 		A = 1 << 0,
 		B = 1 << 1,
 		Select = 1 << 2,