➕ Experimental anti-snapback

src/main/java/dev/isxander/controlify/controller/gamepad/GamepadController.java

@@ -5,9 +5,11 @@ import dev.isxander.controlify.bindings.ControllerBindings;
 import dev.isxander.controlify.controller.AbstractController;
 import dev.isxander.controlify.controller.BatteryLevel;
 import dev.isxander.controlify.controller.hid.ControllerHIDService;
+import dev.isxander.controlify.debug.DebugProperties;
 import dev.isxander.controlify.driver.*;
 import dev.isxander.controlify.rumble.RumbleManager;
 import dev.isxander.controlify.rumble.RumbleSource;
+import dev.isxander.controlify.utils.ControllerUtils;
 import net.minecraft.resources.ResourceLocation;
 import org.lwjgl.glfw.GLFW;
 
@@ -23,6 +25,8 @@ public class GamepadController extends AbstractController<GamepadState, GamepadC
     private final GamepadDrivers drivers;
     private final Set<Driver> uniqueDrivers;
 
+    private int antiSnapbackTicksL, antiSnapbackTicksR;
+
     public GamepadController(int joystickId, ControllerHIDService.ControllerHIDInfo hidInfo) {
         super(joystickId, hidInfo);
         if (!GLFW.glfwJoystickIsGamepad(joystickId))
@@ -64,6 +68,23 @@ public class GamepadController extends AbstractController<GamepadState, GamepadC
                 .leftJoystickDeadZone(config().leftStickDeadzoneX, config().leftStickDeadzoneY)
                 .rightJoystickDeadZone(config().rightStickDeadzoneX, config().rightStickDeadzoneY);
 
+        if (DebugProperties.USE_SNAPBACK) {
+            if (antiSnapbackTicksL > 0) {
+                deadzoneAxesState = deadzoneAxesState.neutraliseLeft();
+                antiSnapbackTicksL--;
+            } else if (ControllerUtils.shouldApplyAntiSnapBack(deadzoneAxesState.leftStickX(), deadzoneAxesState.leftStickY(), prevState.gamepadAxes().leftStickX(), prevState.gamepadAxes().leftStickY(), 0.08f)) {
+                antiSnapbackTicksL = 2;
+                deadzoneAxesState = deadzoneAxesState.neutraliseLeft();
+            }
+            if (antiSnapbackTicksR > 0) {
+                deadzoneAxesState = deadzoneAxesState.neutraliseRight();
+                antiSnapbackTicksR--;
+            } else if (ControllerUtils.shouldApplyAntiSnapBack(deadzoneAxesState.rightStickX(), deadzoneAxesState.rightStickY(), prevState.gamepadAxes().rightStickX(), prevState.gamepadAxes().rightStickY(), 0.08f)) {
+                antiSnapbackTicksR = 2;
+                deadzoneAxesState = deadzoneAxesState.neutraliseRight();
+            }
+        }
+
         GamepadState.GyroState gyroState = drivers.gyroDriver().getGyroState();
 
         state = new GamepadState(deadzoneAxesState, basicState.axes(), basicState.buttons(), gyroState, absoluteGyro);

src/main/java/dev/isxander/controlify/controller/gamepad/GamepadState.java

@@ -177,6 +177,14 @@ public final class GamepadState implements ControllerState {
                     ControllerUtils.deadzone(rightTrigger, deadZone)
             );
         }
+
+        public AxesState neutraliseLeft() {
+            return new AxesState(0, 0, rightStickX, rightStickY, leftTrigger, rightTrigger);
+        }
+
+        public AxesState neutraliseRight() {
+            return new AxesState(leftStickX, leftStickY, 0, 0, leftTrigger, rightTrigger);
+        }
     }
 
     public record ButtonState(

src/main/java/dev/isxander/controlify/controller/sdl2/SDL2NativesManager.java

@@ -80,6 +80,7 @@ public class SDL2NativesManager {
         // without calling JoystickUpdate, which we don't do.
         SDL.SDL_SetHint(SDL_HINT_JOYSTICK_RAWINPUT, "0");
         // better rumble
+        SDL.SDL_SetHint(SDL_HINT_JOYSTICK_HIDAPI, "1");
         SDL.SDL_SetHint(SDL_HINT_JOYSTICK_HIDAPI_PS4_RUMBLE, "1");
         SDL.SDL_SetHint(SDL_HINT_JOYSTICK_HIDAPI_PS5_RUMBLE, "1");
         SDL.SDL_SetHint(SDL_HINT_JOYSTICK_HIDAPI_STEAM, "1");

src/main/java/dev/isxander/controlify/debug/DebugProperties.java

@@ -20,6 +20,8 @@ public class DebugProperties {
     public static final boolean PRINT_GYRO = boolProp("controlify.debug.print_gyro", false, false);
     /* Print what drivers are being used */
     public static final boolean PRINT_DRIVER = boolProp("controlify.debug.print_driver", true, true);
+    /* Use experimental anti-snapback */
+    public static final boolean USE_SNAPBACK = boolProp("controlify.debug.use_snapback", false, false);
 
     public static void printProperties() {
         if (properties.stream().noneMatch(prop -> prop.enabled() != prop.def()))

src/main/java/dev/isxander/controlify/utils/ControllerUtils.java

@@ -1,7 +1,40 @@
 package dev.isxander.controlify.utils;
 
+import net.minecraft.util.Mth;
+
 public class ControllerUtils {
     public static float deadzone(float value, float deadzone) {
         return (value - Math.copySign(Math.min(deadzone, Math.abs(value)), value)) / (1 - deadzone);
     }
+
+    public static float applyCircularityX(float x, float y) {
+        return (float) (x * Math.sqrt(1 - (y * y) / 2));
+    }
+    public static float applyCircularityY(float x, float y) {
+        return (float) (y * Math.sqrt(1 - (x * x) / 2));
+    }
+
+    public static boolean shouldApplyAntiSnapBack(float x, float y, float px, float py, float threshold) {
+        float dx = x - px;
+        float dy = y - py;
+        float distanceSquared = dx * dx + dy * dy;
+
+        boolean isSnap = distanceSquared >= threshold * threshold;
+        boolean hasCrossedOrigin = Math.signum(x) != Math.signum(px) && Math.signum(y) != Math.signum(py);
+
+        if (isSnap && hasCrossedOrigin) {
+            // t is the distance from the origin to the middle of the line
+            float t = (-x * (px - x) + -y * (py - y)) / distanceSquared;
+            t = Mth.clamp(t, 0, 1);
+
+            // Calculate the distance from the middle of the line to the origin
+            double distanceToMiddle = Math.sqrt(Math.pow(-t * x + t * px, 2)
+                    + Math.pow(-t * y + t * py, 2));
+
+            // If the distance is less than 0.05, then the stick is close enough to the middle to be snap-backed
+            return distanceToMiddle <= 0.01;
+        }
+
+        return false;
+    }
 }