refactor: use DirectInput Escape for LED control instead of SDK DLL

Author: privaloops

Common Files/LogitechLED.cpp

@@ -3,6 +3,39 @@
 #include <stdio.h>
 #include <stdarg.h>
 
+// --- Logitech LED Escape protocol (from SDK "Independent" sample) ---
+
+static const DWORD ESCAPE_COMMAND_LEDS = 0;
+static const DWORD LEDS_VERSION_NUMBER = 0x00000001;
+
+struct LedsRpmData
+{
+	FLOAT currentRPM;
+	FLOAT rpmFirstLedTurnsOn;
+	FLOAT rpmRedLine;
+};
+
+struct WheelData
+{
+	DWORD size;
+	DWORD versionNbr;
+	LedsRpmData rpmData;
+};
+
+// --- Known Logitech wheel VID/PIDs ---
+
+static const DWORD LOGITECH_VID = 0x046D;
+static const DWORD KNOWN_PIDS[] = {
+	0xC24F,  // G29
+	0xC260,  // G920 (no RPM LEDs but detected for completeness)
+	0xC262,  // G920 Xbox
+	0xC266,  // G923 PS
+	0xC267,  // G923 PS (alt)
+	0xC26D,  // G923 Xbox (alt PID)
+	0xC26E,  // G923 Xbox
+};
+static const int NUM_PIDS = sizeof(KNOWN_PIDS) / sizeof(KNOWN_PIDS[0]);
+
 // --- Logging ---
 
 static FILE* g_logFile = NULL;
@@ -23,16 +56,20 @@ static void Log(const char* fmt, ...)
 	OutputDebugStringA("\n");
 }
 
+static bool IsKnownPID(DWORD pid)
+{
+	for (int i = 0; i < NUM_PIDS; i++)
+		if (KNOWN_PIDS[i] == pid) return true;
+	return false;
+}
+
 // --- LogitechLED ---
 
 LogitechLED::LogitechLED()
-	: m_sdkModule(NULL)
+	: m_dinputDll(NULL)
+	, m_pDI(NULL)
+	, m_pDevice(NULL)
 	, m_available(false)
-	, m_pfnInit(NULL)
-	, m_pfnUpdate(NULL)
-	, m_pfnIsConnected(NULL)
-	, m_pfnPlayLeds(NULL)
-	, m_pfnShutdown(NULL)
 {
 }
 
@@ -43,111 +80,217 @@ LogitechLED::~LogitechLED()
 
 void LogitechLED::Close()
 {
-	if (m_pfnShutdown && m_available)
-		m_pfnShutdown();
+	if (m_pDevice)
+	{
+		m_pDevice->Unacquire();
+		m_pDevice->Release();
+		m_pDevice = NULL;
+	}
+
+	if (m_pDI)
+	{
+		m_pDI->Release();
+		m_pDI = NULL;
+	}
 
-	if (m_sdkModule)
+	if (m_dinputDll)
 	{
-		FreeLibrary(m_sdkModule);
-		m_sdkModule = NULL;
+		FreeLibrary(m_dinputDll);
+		m_dinputDll = NULL;
 	}
 
 	m_available = false;
-	m_pfnInit = NULL;
-	m_pfnUpdate = NULL;
-	m_pfnIsConnected = NULL;
-	m_pfnPlayLeds = NULL;
-	m_pfnShutdown = NULL;
 }
 
 bool LogitechLED::IsAvailable() const
 {
 	return m_available;
 }
 
+// --- Device enumeration callback ---
+
+BOOL CALLBACK LogitechLED::EnumDevicesCallback(LPCDIDEVICEINSTANCEA lpddi, LPVOID pvRef)
+{
+	EnumContext* ctx = (EnumContext*)pvRef;
+
+	DWORD vid = LOWORD(lpddi->guidProduct.Data1);
+	DWORD pid = HIWORD(lpddi->guidProduct.Data1);
+
+	Log("  Enum: VID=0x%04X PID=0x%04X Name='%s'", vid, pid, lpddi->tszProductName);
+
+	if (vid == LOGITECH_VID && IsKnownPID(pid))
+	{
+		Log("  -> Logitech wheel found!");
+		ctx->deviceGuid = lpddi->guidInstance;
+		ctx->found = true;
+		return DIENUM_STOP;
+	}
+
+	return DIENUM_CONTINUE;
+}
+
+// --- Init ---
+
 bool LogitechLED::Init()
 {
-	Log("LogitechLED::Init() - Logitech SDK mode");
+	Log("LogitechLED::Init() - DirectInput Escape mode");
 
 	if (m_available)
 		return true;
 
-	// Load the SDK DLL
-	m_sdkModule = LoadLibraryA("LogitechSteeringWheel.dll");
-	if (!m_sdkModule)
+	// Load the REAL dinput8.dll from System32 (not our wrapper)
+	char sysDir[MAX_PATH];
+	GetSystemDirectoryA(sysDir, MAX_PATH);
+	strcat_s(sysDir, "\\dinput8.dll");
+
+	m_dinputDll = LoadLibraryA(sysDir);
+	if (!m_dinputDll)
+	{
+		Log("Failed to load real dinput8.dll from %s (err=%lu)", sysDir, GetLastError());
+		return false;
+	}
+
+	Log("Real dinput8.dll loaded from %s", sysDir);
+
+	// Get the real DirectInput8Create
+	typedef HRESULT(WINAPI* PFN_DirectInput8Create)(HINSTANCE, DWORD, REFIID, LPVOID*, LPUNKNOWN);
+	PFN_DirectInput8Create pfnCreate = (PFN_DirectInput8Create)GetProcAddress(m_dinputDll, "DirectInput8Create");
+	if (!pfnCreate)
+	{
+		Log("DirectInput8Create not found in real dinput8.dll");
+		Close();
+		return false;
+	}
+
+	// Create DirectInput interface
+	HRESULT hr = pfnCreate(GetModuleHandle(NULL), DIRECTINPUT_VERSION, IID_IDirectInput8A, (LPVOID*)&m_pDI, NULL);
+	if (FAILED(hr))
 	{
-		Log("LogitechSteeringWheel.dll not found (err=%lu)", GetLastError());
-		Log("Ensure Logitech G Hub is installed and LogitechSteeringWheel.dll is alongside the game.");
+		Log("DirectInput8Create failed (hr=0x%08X)", hr);
+		Close();
 		return false;
 	}
 
-	Log("LogitechSteeringWheel.dll loaded");
+	Log("DirectInput8 interface created");
+
+	// Enumerate game controllers to find Logitech wheel
+	EnumContext ctx = {};
+	ctx.found = false;
+
+	Log("Enumerating game controllers...");
+	m_pDI->EnumDevices(DI8DEVCLASS_GAMECTRL, EnumDevicesCallback, &ctx, DIEDFL_ATTACHEDONLY);
+
+	if (!ctx.found)
+	{
+		Log("No Logitech wheel found");
+		Close();
+		return false;
+	}
 
-	// Resolve function pointers
-	m_pfnInit = (PFN_LogiSteeringInitialize)GetProcAddress(m_sdkModule, "LogiSteeringInitialize");
-	m_pfnUpdate = (PFN_LogiUpdate)GetProcAddress(m_sdkModule, "LogiUpdate");
-	m_pfnIsConnected = (PFN_LogiIsConnected)GetProcAddress(m_sdkModule, "LogiIsConnected");
-	m_pfnPlayLeds = (PFN_LogiPlayLeds)GetProcAddress(m_sdkModule, "LogiPlayLeds");
-	m_pfnShutdown = (PFN_LogiSteeringShutdown)GetProcAddress(m_sdkModule, "LogiSteeringShutdown");
+	// Create device
+	hr = m_pDI->CreateDevice(ctx.deviceGuid, &m_pDevice, NULL);
+	if (FAILED(hr))
+	{
+		Log("CreateDevice failed (hr=0x%08X)", hr);
+		Close();
+		return false;
+	}
 
-	if (!m_pfnInit || !m_pfnUpdate || !m_pfnPlayLeds || !m_pfnShutdown)
+	// Set data format
+	hr = m_pDevice->SetDataFormat(&c_dfDIJoystick2);
+	if (FAILED(hr))
 	{
-		Log("Failed to resolve SDK functions (Init=%p Update=%p PlayLeds=%p Shutdown=%p)",
-			m_pfnInit, m_pfnUpdate, m_pfnPlayLeds, m_pfnShutdown);
-		FreeLibrary(m_sdkModule);
-		m_sdkModule = NULL;
+		Log("SetDataFormat failed (hr=0x%08X)", hr);
+		Close();
 		return false;
 	}
 
-	Log("SDK functions resolved");
+	// Set cooperative level: background + non-exclusive (don't steal from game)
+	HWND hwnd = GetForegroundWindow();
+	if (!hwnd) hwnd = GetDesktopWindow();
 
-	// Initialize the steering wheel SDK
-	if (!m_pfnInit(false))
+	hr = m_pDevice->SetCooperativeLevel(hwnd, DISCL_BACKGROUND | DISCL_NONEXCLUSIVE);
+	if (FAILED(hr))
 	{
-		Log("LogiSteeringInitialize() failed - is G Hub running?");
-		FreeLibrary(m_sdkModule);
-		m_sdkModule = NULL;
+		Log("SetCooperativeLevel failed (hr=0x%08X)", hr);
+		Close();
 		return false;
 	}
 
-	Log("SDK initialized");
+	// Acquire the device
+	hr = m_pDevice->Acquire();
+	if (FAILED(hr))
+	{
+		Log("Acquire failed (hr=0x%08X)", hr);
+		Close();
+		return false;
+	}
 
-	// Give the SDK a moment to enumerate devices
-	m_pfnUpdate();
+	Log("Device acquired, testing Escape LED command...");
 
-	if (m_pfnIsConnected && m_pfnIsConnected(0))
-		Log("Steering wheel detected at index 0");
-	else
-		Log("No wheel detected yet (will retry on first LED update)");
+	// Test: try to clear LEDs to verify Escape() works
+	if (!PlayLedsEscape(0.0f, 200.0f, 1000.0f))
+	{
+		Log("Escape LED command not supported on this device");
+		Close();
+		return false;
+	}
 
 	m_available = true;
-	Log("LogitechLED ready");
+	Log("LogitechLED ready (DirectInput Escape mode)");
+	return true;
+}
+
+// --- LED control via Escape ---
+
+bool LogitechLED::PlayLedsEscape(float currentRPM, float rpmFirstLed, float rpmRedLine)
+{
+	if (!m_pDevice)
+		return false;
+
+	WheelData wheelData;
+	ZeroMemory(&wheelData, sizeof(wheelData));
+	wheelData.size = sizeof(WheelData);
+	wheelData.versionNbr = LEDS_VERSION_NUMBER;
+	wheelData.rpmData.currentRPM = currentRPM;
+	wheelData.rpmData.rpmFirstLedTurnsOn = rpmFirstLed;
+	wheelData.rpmData.rpmRedLine = rpmRedLine;
+
+	DIEFFESCAPE escape;
+	ZeroMemory(&escape, sizeof(escape));
+	escape.dwSize = sizeof(DIEFFESCAPE);
+	escape.dwCommand = ESCAPE_COMMAND_LEDS;
+	escape.lpvInBuffer = &wheelData;
+	escape.cbInBuffer = sizeof(wheelData);
+
+	HRESULT hr = m_pDevice->Escape(&escape);
+	if (FAILED(hr))
+	{
+		Log("Escape failed (hr=0x%08X)", hr);
+		return false;
+	}
+
 	return true;
 }
 
 bool LogitechLED::SetLEDsFromPercent(double percent)
 {
-	if (!m_available || !m_pfnPlayLeds || !m_pfnUpdate)
+	if (!m_available)
 		return false;
 
 	if (percent < 0.0) percent = 0.0;
 	if (percent > 1.0) percent = 1.0;
 
-	m_pfnUpdate();
-
-	// Map FFB strength (0.0-1.0) to RPM values.
-	// rpmFirstLed=200: first LED lights at 20% strength
-	// rpmRedLine=1000: all LEDs at 100% strength
+	// Map FFB strength (0.0-1.0) to RPM values
 	float currentRPM = (float)(percent * 1000.0);
-	return m_pfnPlayLeds(0, currentRPM, 200.0f, 1000.0f);
+	return PlayLedsEscape(currentRPM, 200.0f, 1000.0f);
 }
 
 bool LogitechLED::SetLEDs(BYTE ledMask)
 {
 	if (!m_available)
 		return false;
 
-	// Map 5-bit mask to approximate percentage
 	int count = 0;
 	for (int i = 0; i < 5; i++)
 		if (ledMask & (1 << i)) count++;
@@ -157,9 +300,8 @@ bool LogitechLED::SetLEDs(BYTE ledMask)
 
 bool LogitechLED::ClearLEDs()
 {
-	if (!m_available || !m_pfnPlayLeds || !m_pfnUpdate)
+	if (!m_available)
 		return false;
 
-	m_pfnUpdate();
-	return m_pfnPlayLeds(0, 0.0f, 200.0f, 1000.0f);
+	return PlayLedsEscape(0.0f, 200.0f, 1000.0f);
 }

Common Files/LogitechLED.h

@@ -1,10 +1,13 @@
 #pragma once
 
+#define DIRECTINPUT_VERSION 0x0800
 #include <windows.h>
+#include <dinput.h>
 
-// Logitech G923/G29 RPM LED controller via Logitech Steering Wheel SDK.
-// Requires Logitech G Hub to be running.
-// Uses dynamic loading: no hard dependency on the SDK DLL.
+// Logitech G923/G29 RPM LED controller via DirectInput Escape().
+// Uses the same mechanism as the Logitech SDK "Independent" sample.
+// Requires Logitech G Hub running (provides the FF driver that handles Escape).
+// No external DLL dependency.
 
 class LogitechLED
 {
@@ -21,19 +24,17 @@ class LogitechLED
 	bool IsAvailable() const;
 
 private:
-	HMODULE m_sdkModule;
+	HMODULE m_dinputDll;
+	LPDIRECTINPUT8A m_pDI;
+	LPDIRECTINPUTDEVICE8A m_pDevice;
 	bool m_available;
 
-	// SDK function pointers
-	typedef bool (__cdecl *PFN_LogiSteeringInitialize)(bool);
-	typedef bool (__cdecl *PFN_LogiUpdate)();
-	typedef bool (__cdecl *PFN_LogiIsConnected)(int);
-	typedef bool (__cdecl *PFN_LogiPlayLeds)(int, float, float, float);
-	typedef void (__cdecl *PFN_LogiSteeringShutdown)();
-
-	PFN_LogiSteeringInitialize m_pfnInit;
-	PFN_LogiUpdate m_pfnUpdate;
-	PFN_LogiIsConnected m_pfnIsConnected;
-	PFN_LogiPlayLeds m_pfnPlayLeds;
-	PFN_LogiSteeringShutdown m_pfnShutdown;
+	struct EnumContext
+	{
+		GUID deviceGuid;
+		bool found;
+	};
+
+	bool PlayLedsEscape(float currentRPM, float rpmFirstLed, float rpmRedLine);
+	static BOOL CALLBACK EnumDevicesCallback(LPCDIDEVICEINSTANCEA lpddi, LPVOID pvRef);
 };