Implement controller gyroscope in SDL

include/panda_sdl/frontend_sdl.hpp

@@ -37,4 +37,6 @@ class FrontendSDL {
 	// And so the user can still use the keyboard to control the analog
 	bool keyboardAnalogX = false;
 	bool keyboardAnalogY = false;
+
+	void setupControllerSensors(SDL_GameController* controller);
 };

include/sdl_gyro.hpp

@@ -0,0 +1,20 @@
+#pragma once
+
+#include <glm/glm.hpp>
+#include <numbers>
+
+#include "services/hid.hpp"
+
+namespace Gyro::SDL {
+	// Convert the rotation data we get from SDL sensor events to rotation data we can feed right to HID
+	// Returns [pitch, roll, yaw]
+	static glm::vec3 convertRotation(glm::vec3 rotation) { 
+		// Flip axes
+		glm::vec3 ret = -rotation;
+		// Convert from radians/s to deg/s and scale by the gyroscope coefficient from the HID service
+		ret *= 180.f / std::numbers::pi;
+		ret *= HIDService::gyroscopeCoeff;
+
+		return ret;
+	}
+}  // namespace Gyro::SDL

include/services/hid.hpp

@@ -88,6 +88,8 @@ class HIDService {
 	}
 
   public:
+	static constexpr float gyroscopeCoeff = 14.375f;  // Same as retail 3DS
+
 	HIDService(Memory& mem, Kernel& kernel) : mem(mem), kernel(kernel) {}
 	void reset();
 	void handleSyncRequest(u32 messagePointer);