From b7fbdfa2a9f85501ac63f191be8b371347b4e239 Mon Sep 17 00:00:00 2001
From: Tony Ferguson <devultj@gmail.com>
Date: Wed, 22 Jul 2026 11:13:14 +0100
Subject: [PATCH] Implement controller joystick deadzone (#5354)

* Implement controller joystick deadzone
* Triggers keep a fixed deadzone
---
 engine/Sandbox.Engine/Game/Preferences.cs            |  6 ++++++
 .../Systems/Input/Controller/Controller.Input.cs     | 12 +++++++++---
 .../menu/Code/Modals/Settings/InputSettings.razor    |  9 +++++++++
 3 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/engine/Sandbox.Engine/Game/Preferences.cs b/engine/Sandbox.Engine/Game/Preferences.cs
index 2a172415..ee746df3 100644
--- a/engine/Sandbox.Engine/Game/Preferences.cs
+++ b/engine/Sandbox.Engine/Game/Preferences.cs
@@ -36,6 +36,12 @@ public static class Preferences
 	[ConVar( "controller_look_speed_pitch", ConVarFlags.Protected, Help = "How fast the camera turns vertically when the stick is pushed all the way up/down (deg/s)", Saved = true, Min = 0.1f, Max = 360.0f )]
 	public static float ControllerLookPitchSpeed { get; internal set; } = 160.0f;
 
+	/// <summary>
+	/// The percentage of joystick travel ignored around the neutral position.
+	/// </summary>
+	[ConVar( "controller_joystick_deadzone", ConVarFlags.Protected, Help = "Percentage of joystick travel ignored around the neutral position", Saved = true, Min = 0.0f, Max = 50.0f )]
+	public static float ControllerJoystickDeadzone { get; internal set; } = 12.5f;
+
 	[ConVar( "controller_analog_speed", ConVarFlags.Protected, Help = "How fast the left joystick moves, for stuff like the virtual cursor in menus", Saved = true, Min = 0.1f, Max = 360.0f )]
 	internal static float ControllerAnalogSpeed { get; set; } = 2.0f;
 
diff --git a/engine/Sandbox.Engine/Systems/Input/Controller/Controller.Input.cs b/engine/Sandbox.Engine/Systems/Input/Controller/Controller.Input.cs
index 70924795..e6b6b263 100644
--- a/engine/Sandbox.Engine/Systems/Input/Controller/Controller.Input.cs
+++ b/engine/Sandbox.Engine/Systems/Input/Controller/Controller.Input.cs
@@ -22,6 +22,11 @@ internal sealed partial class Controller
 
 	List<InputAxis> ControllerAxes { get; set; } = new();
 
+	/// <summary>
+	/// Triggers always use a fixed deadzone, they're not affected by <see cref="Preferences.ControllerJoystickDeadzone"/>.
+	/// </summary>
+	const float TriggerDeadzone = 0.125f;
+
 	/// <summary>
 	/// Get an axis
 	/// </summary>
@@ -44,9 +49,10 @@ internal sealed partial class Controller
 		float flValue = inputValue;
 		float normalizedAxis = flValue.Remap( Controller.AXIS_RANGE.x, Controller.AXIS_RANGE.y, -1, 1 );
 
-		// 12.5% deadzone
-		// todo: make this modifiable 
-		var deadzone = 0.125f;
+		var deadzone = axis < NativeEngine.GameControllerAxis.TriggerLeft
+			? Preferences.ControllerJoystickDeadzone / 100.0f
+			: TriggerDeadzone;
+
 		if ( MathF.Abs( normalizedAxis ) <= deadzone ) normalizedAxis = 0f;
 
 		if ( normalizedAxis > 0f )
diff --git a/game/addons/menu/Code/Modals/Settings/InputSettings.razor b/game/addons/menu/Code/Modals/Settings/InputSettings.razor
index dc6f4164..3e6e0d46 100644
--- a/game/addons/menu/Code/Modals/Settings/InputSettings.razor
+++ b/game/addons/menu/Code/Modals/Settings/InputSettings.razor
@@ -37,6 +37,11 @@
             <div class="is-label">Look Pitch Speed</div>
             <SliderControl Min=@(0) Max=@(360) Value:bind=@ControllerLookSpeedPitch ShowTextEntry="@true"></SliderControl>
         </row>
+
+        <row>
+            <div class="is-label">Joystick Deadzone (%)</div>
+            <SliderControl Min=@(0) Max=@(50) Step=@(0.5f) Value:bind=@ControllerJoystickDeadzone ShowTextEntry="@true"></SliderControl>
+        </row>
 	</div>
 
      <SettingsFooter OnCancel=@OnCancel OnRestore=@OnRestore OnApply=@OnApply></SettingsFooter>
@@ -50,6 +55,7 @@
 
 	public float ControllerLookSpeedYaw { get; set; }
 	public float ControllerLookSpeedPitch { get; set; }
+	public float ControllerJoystickDeadzone { get; set; }
 
 	public bool InvertMousePitch { get; set; }
 	public bool InvertMouseYaw { get; set; }
@@ -81,6 +87,7 @@
 		ConsoleSystem.SetValue("sensitivity", 5);
 		ConsoleSystem.SetValue("controller_look_speed_yaw", 270);
 		ConsoleSystem.SetValue("controller_look_speed_pitch", 160);
+		ConsoleSystem.SetValue("controller_joystick_deadzone", 12.5f);
 		ConsoleSystem.SetValue("mouse_pitch_inverted", false);
 		ConsoleSystem.SetValue("mouse_yaw_inverted", false);
 	}
@@ -90,6 +97,7 @@
         MouseSensitivity = ConsoleSystem.GetValue("sensitivity").ToFloat();
         ControllerLookSpeedYaw = ConsoleSystem.GetValue("controller_look_speed_yaw").ToFloat();
         ControllerLookSpeedPitch = ConsoleSystem.GetValue("controller_look_speed_pitch").ToFloat();
+		ControllerJoystickDeadzone = ConsoleSystem.GetValue("controller_joystick_deadzone").ToFloat();
 		InvertMousePitch = ConsoleSystem.GetValue("mouse_pitch_inverted").ToBool();
 		InvertMouseYaw = ConsoleSystem.GetValue("mouse_yaw_inverted").ToBool();
     }
@@ -99,6 +107,7 @@
         ConsoleSystem.SetValue( "sensitivity", MouseSensitivity );
         ConsoleSystem.SetValue( "controller_look_speed_yaw", ControllerLookSpeedYaw );
 		ConsoleSystem.SetValue( "controller_look_speed_pitch", ControllerLookSpeedPitch );
+		ConsoleSystem.SetValue( "controller_joystick_deadzone", ControllerJoystickDeadzone );
 		ConsoleSystem.SetValue( "mouse_pitch_inverted", InvertMousePitch );
 		ConsoleSystem.SetValue( "mouse_yaw_inverted", InvertMouseYaw );
     }