Add vJoy steering passthrough to the game bridge

For games like Assetto Corsa that cannot disable their own force feedback: MAIRA passes the wheelbase steering axis through to vJoy, the game is bound to the vJoy X axis, and its FFB goes to vJoy instead of the real wheel. Includes a steering test mode with position and sweep buttons for binding the axis in the game, a warning when the vJoy driver is missing, and a fix so the wheel position is tracked from the selected steering device before force feedback initializes.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: mherbold

MarvinsAIRARefactored/App.xaml.cs

@@ -710,14 +710,14 @@ private static void WorkerThread()
 						app.Sounds.Tick( app );
 						app.Graph.Tick( app );
 						app.SteeringEffects.Tick( app );
+						app.GameBridge.Tick( app );
 						app.VirtualJoystick.Tick( app );
 						app.TimingMarkers.Tick( app );
 						app.Telemetry.Tick( app );
 						app.Commentary.Tick( app );
 						app.TyphoonWind.Tick( app );
 						app.GTensioner.Tick( app );
 						app.CloudService.Tick( app );
-						app.GameBridge.Tick( app );
 
 						app.GripOMeterWindow?.Tick( app );
 						app.GapMonitorWindow?.Tick( app );

MarvinsAIRARefactored/Artwork/Buttons/steering-wheel-90-right.png

@@ -245,6 +245,13 @@ public void PollDevices( float deltaSeconds )
 
 		var app = App.Instance!;
 
+		// track the wheel position on the SELECTED steering device from settings, not on the initialized
+		// force feedback device - force feedback is only initialized once a simulator connects (RacingWheel
+		// runs on the multimedia timer, which is suspended until then), but the wheel position is needed
+		// earlier than that (the game bridge's vJoy steering passthrough runs while the game is still in
+		// its menus, before any telemetry flows)
+		var steeringDeviceInstanceGuid = ( _forceFeedbackDeviceInstanceGuid != Guid.Empty ) ? _forceFeedbackDeviceInstanceGuid : DataContext.DataContext.Instance.Settings.RacingWheelSteeringDeviceGuid;
+
 		if ( _joystickInfoListNeedsToBeUpdated )
 		{
 			_joystickInfoListNeedsToBeUpdated = false;
@@ -284,7 +291,7 @@ public void PollDevices( float deltaSeconds )
 
 					joystickInfo._joystickUpdates = joystickInfo._joystick.GetBufferedData();
 
-					if ( joystickInfo._instanceGuid == _forceFeedbackDeviceInstanceGuid )
+					if ( joystickInfo._instanceGuid == steeringDeviceInstanceGuid )
 					{
 						if ( joystickInfo._xAxisProperties != null )
 						{

MarvinsAIRARefactored/Artwork/Buttons/steering-wheel-sweep-orange.png

@@ -1,4 +1,5 @@
 
+using MarvinsAIRARefactored.Controls;
 using MarvinsAIRARefactored.GameBridges;
 
 using static MarvinsAIRARefactored.Windows.MainWindow;
@@ -124,6 +125,8 @@ public void Pump( double totalSeconds )
 
 	public void Tick( App app )
 	{
+		UpdateSteeringPassthrough( app );
+
 		ActiveAdapter?.Tick( app );
 
 		_updateCounter--;
@@ -135,6 +138,15 @@ public void Tick( App app )
 
 		_updateCounter = UpdateInterval;
 
+		// keep the vJoy driver warning and the sweep button's blink fresh while the game bridge page is
+		// showing - the fault is only discovered after the passthrough first tries to initialize the
+		// device, and the sweep can be cancelled by the toggles rather than by its own button
+		if ( MairaAppMenuPopup.CurrentAppPage == AppPage.GameBridge )
+		{
+			_gameBridgePage.UpdateVJoyStatus( app );
+			_gameBridgePage.UpdateSweepButton( app );
+		}
+
 		if ( _transitioning )
 		{
 			return;
@@ -161,6 +173,86 @@ public void Tick( App app )
 		}
 	}
 
+	// When enabled, the wheelbase's steering axis is passed through to the vJoy device's X axis every tick.
+	// This is for games that provide no way to disable their built-in force feedback (Assetto Corsa, for
+	// example): the user binds the game's steering input to the vJoy X axis instead of the real wheel, so the
+	// game sends its force feedback to the vJoy device (which discards it) and MAIRA keeps sole control of
+	// the real wheelbase. This tick runs BEFORE VirtualJoystick.Tick in the app worker loop, so the position
+	// written here goes out to vJoy in the same frame.
+	private bool _steeringPassthroughActive = false;
+	private int _steeringPassthroughShutdownCountdown = 0;
+
+	// the steering sweep continuously oscillates the vJoy axis (one full left-right-left cycle every two
+	// seconds) - games like AC ignore controller input while their window is not in the foreground, so the
+	// user arms the sweep in MAIRA, clicks over to the game, and the game then sees the axis moving
+	public bool SteeringSweepActive { get; set; } = false;
+
+	private const double SteeringSweepPeriodSeconds = 2.0;
+
+	private double _steeringSweepPhase = 0.0;
+
+	private void UpdateSteeringPassthrough( App app )
+	{
+		var settings = DataContext.DataContext.Instance.Settings;
+
+		if ( settings.GameBridgeSendSteeringToVJoy || settings.GameBridgeSteeringTestEnabled )
+		{
+			if ( !app.VirtualJoystick.Initialized && !app.VirtualJoystick.Faulted )
+			{
+				app.VirtualJoystick.Initialize();
+			}
+
+			// in steering test mode the vJoy axis is driven by the test buttons on the game bridge page
+			// instead of the real wheel - this lets the user move ONLY the vJoy axis while binding the
+			// steering input in the game, so the game cannot mistake the real wheel for the moving axis
+			if ( !settings.GameBridgeSteeringTestEnabled )
+			{
+				SteeringSweepActive = false;
+
+				app.VirtualJoystick.Steering = app.DirectInput.ForceFeedbackWheelPosition;
+			}
+			else if ( SteeringSweepActive )
+			{
+				_steeringSweepPhase += 2.0 * Math.PI / ( SteeringSweepPeriodSeconds * App.TimerTicksPerSecond );
+
+				app.VirtualJoystick.Steering = (float) Math.Sin( _steeringSweepPhase );
+			}
+			else
+			{
+				_steeringSweepPhase = 0.0;
+			}
+
+			if ( !_steeringPassthroughActive && app.VirtualJoystick.Initialized )
+			{
+				app.Logger.WriteLine( "[GameBridge] vJoy steering passthrough started" );
+			}
+
+			_steeringPassthroughActive = true;
+			_steeringPassthroughShutdownCountdown = 2;
+		}
+		else if ( _steeringPassthroughActive )
+		{
+			// on the way out, center the axis first and give VirtualJoystick.Tick one frame to actually push
+			// the zero to the device before it is released
+			app.VirtualJoystick.Steering = 0f;
+
+			_steeringPassthroughShutdownCountdown--;
+
+			if ( _steeringPassthroughShutdownCountdown <= 0 )
+			{
+				_steeringPassthroughActive = false;
+				SteeringSweepActive = false;
+
+				app.Logger.WriteLine( "[GameBridge] vJoy steering passthrough stopped" );
+
+				if ( app.VirtualJoystick.Initialized )
+				{
+					app.VirtualJoystick.Shutdown();
+				}
+			}
+		}
+	}
+
 	private void Activate( App app, GameBridgeAdapter adapter )
 	{
 		app.Logger.WriteLine( $"[GameBridge] Activating the {adapter.GameName} bridge" );

MarvinsAIRARefactored/Artwork/Buttons/steering-wheel-sweep.png

@@ -1302,7 +1302,9 @@ public void Tick( App app )
 
 				if ( app.Simulator.TrackDisplayName != "Centripetal Circuit" )
 				{
-					if ( app.VirtualJoystick.Initialized )
+					// the game bridge's steering passthrough shares the vJoy device - if it is enabled, leave
+					// the device alone here or the two features would fight over acquire/release every tick
+					if ( app.VirtualJoystick.Initialized && !DataContext.DataContext.Instance.Settings.GameBridgeSendSteeringToVJoy )
 					{
 						app.VirtualJoystick.Shutdown();
 					}

MarvinsAIRARefactored/Components/DirectInput.cs

@@ -32,6 +32,8 @@ public class VirtualJoystick
 	private bool _initialized = false;
 	private bool _faulted = false;
 
+	private int _consecutiveUpdateFailures = 0;
+
 	public bool Initialized { get => _initialized; }
 	public bool Faulted { get => _faulted; }
 
@@ -84,6 +86,10 @@ public void Initialize()
 				{
 					_vJoy.ResetVJD( JoystickId );
 
+					var xAxisExists = _vJoy.GetVJDAxisExist( JoystickId, HID_USAGES.HID_USAGE_X );
+					var yAxisExists = _vJoy.GetVJDAxisExist( JoystickId, HID_USAGES.HID_USAGE_Y );
+					var zAxisExists = _vJoy.GetVJDAxisExist( JoystickId, HID_USAGES.HID_USAGE_Z );
+
 					_vJoy.GetVJDAxisMin( JoystickId, HID_USAGES.HID_USAGE_X, ref _minimumX );
 					_vJoy.GetVJDAxisMax( JoystickId, HID_USAGES.HID_USAGE_X, ref _maximumX );
 
@@ -93,7 +99,22 @@ public void Initialize()
 					_vJoy.GetVJDAxisMin( JoystickId, HID_USAGES.HID_USAGE_Z, ref _minimumZ );
 					_vJoy.GetVJDAxisMax( JoystickId, HID_USAGES.HID_USAGE_Z, ref _maximumZ );
 
-					_initialized = true;
+					app.Logger.WriteLine( $"[VirtualJoystick] Axes - X: {xAxisExists} ({_minimumX}..{_maximumX}), Y: {yAxisExists} ({_minimumY}..{_maximumY}), Z: {zAxisExists} ({_minimumZ}..{_maximumZ})" );
+
+					// without an X axis the steering can never move - flag it as a fault instead of silently
+					// writing a constant zero forever (the same goes for a degenerate axis range)
+					if ( !xAxisExists || ( _minimumX == _maximumX ) )
+					{
+						app.Logger.WriteLine( $"[VirtualJoystick] Joystick {JoystickId} has no usable X axis - reconfigure the vJoy device with an X axis!" );
+
+						_vJoy.RelinquishVJD( JoystickId );
+
+						_faulted = true;
+					}
+					else
+					{
+						_initialized = true;
+					}
 				}
 			}
 		}
@@ -141,13 +162,26 @@ public void Tick( App app )
 
 			if ( !_vJoy.UpdateVJD( JoystickId, ref _joystickState ) )
 			{
+				// log the first failure and then once every ~5 seconds - if the re-acquire below keeps
+				// succeeding this would otherwise loop forever in silence with the axes frozen
+				_consecutiveUpdateFailures++;
+
+				if ( ( _consecutiveUpdateFailures == 1 ) || ( _consecutiveUpdateFailures % 300 == 0 ) )
+				{
+					app.Logger.WriteLine( $"[VirtualJoystick] UpdateVJD failed on joystick {JoystickId} ({_consecutiveUpdateFailures}x)" );
+				}
+
 				if ( !_vJoy.AcquireVJD( JoystickId ) )
 				{
 					app.Logger.WriteLine( $"[VirtualJoystick] Joystick {JoystickId} could not be re-acquired" );
 
 					_initialized = false;
 				}
 			}
+			else
+			{
+				_consecutiveUpdateFailures = 0;
+			}
 		}
 	}
 }

MarvinsAIRARefactored/Components/GameBridge.cs

@@ -14286,6 +14286,55 @@ public bool GameBridgeRaceRoomRacingExperienceEnabled
 
 	#endregion
 
+	#region Game bridge - send steering to vJoy
+
+	private bool _gameBridgeSendSteeringToVJoy = false;
+
+	public bool GameBridgeSendSteeringToVJoy
+	{
+		get => _gameBridgeSendSteeringToVJoy;
+
+		set
+		{
+			if ( value != _gameBridgeSendSteeringToVJoy )
+			{
+				_gameBridgeSendSteeringToVJoy = value;
+
+				// the steering test mode rides on top of the vJoy passthrough, so switching the passthrough
+				// off also switches the test mode off (its switch is disabled in the UI while this is off)
+				if ( !value )
+				{
+					GameBridgeSteeringTestEnabled = false;
+				}
+
+				OnPropertyChanged();
+			}
+		}
+	}
+
+	#endregion
+
+	#region Game bridge - steering test enabled
+
+	private bool _gameBridgeSteeringTestEnabled = false;
+
+	public bool GameBridgeSteeringTestEnabled
+	{
+		get => _gameBridgeSteeringTestEnabled;
+
+		set
+		{
+			if ( value != _gameBridgeSteeringTestEnabled )
+			{
+				_gameBridgeSteeringTestEnabled = value;
+
+				OnPropertyChanged();
+			}
+		}
+	}
+
+	#endregion
+
 	#region App Manager - Enabled
 
 	private bool _appManagerEnabled = true;

MarvinsAIRARefactored/Components/SteeringEffects.cs

@@ -187,7 +187,10 @@
     <Resource Include="Artwork\Buttons\square-default.png" />
     <Resource Include="Artwork\Buttons\square-pressed.png" />
     <Resource Include="Artwork\Buttons\steering-wheel-90-left.png" />
+    <Resource Include="Artwork\Buttons\steering-wheel-90-right.png" />
     <Resource Include="Artwork\Buttons\steering-wheel-center.png" />
+    <Resource Include="Artwork\Buttons\steering-wheel-sweep.png" />
+    <Resource Include="Artwork\Buttons\steering-wheel-sweep-orange.png" />
     <Resource Include="Artwork\Buttons\steering-wheel-left.png" />
     <Resource Include="Artwork\Buttons\steering-wheel-right.png" />
     <Resource Include="Artwork\Buttons\stop-calibration.png" />