Add configurable cursor deadzone (0-15 degrees)

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01YVREx3uo7nz1FEhzveWTUh

src/main/java/dev/lumareth/improvedAerodynamics/flight/CursorAimConfig.java

@@ -8,6 +8,7 @@ public final class CursorAimConfig {
 
     public static final ForgeConfigSpec.BooleanValue ENABLED;
     public static final ForgeConfigSpec.DoubleValue FULL_DEFLECTION_DEGREES;
+    public static final ForgeConfigSpec.DoubleValue DEADZONE_DEGREES;
     public static final ForgeConfigSpec.DoubleValue MAX_TURN_RATE_DEGREES;
     public static final ForgeConfigSpec.DoubleValue MAX_ROLL_RATE_DEGREES;
     public static final ForgeConfigSpec.DoubleValue MAX_BANK_DEGREES;
@@ -25,6 +26,9 @@ public final class CursorAimConfig {
         FULL_DEFLECTION_DEGREES = builder.comment("Angle of the cursor from the gun reticle at which the virtual pilot asks for full deflection: the maximum bank",
                         "sideways, the full pitch rate up or down")
                 .defineInRange("fullDeflectionDegrees", 30.0, 5.0, 90.0);
+        DEADZONE_DEGREES = builder.comment("Radius around the gun reticle in degrees inside which the cursor commands nothing, so the craft flies straight.",
+                        "Outside it the command grows from zero, there is no jump at the edge")
+                .defineInRange("deadzoneDegrees", 3.0, 0.0, 15.0);
         MAX_TURN_RATE_DEGREES = builder.comment("Turn rate in degrees per second the pilot asks for at full deflection, both for the turn at maximum bank and for pitching")
                 .defineInRange("maxTurnRateDegrees", 40.0, 5.0, 360.0);
         MAX_ROLL_RATE_DEGREES = builder.comment("Fastest roll in degrees per second the pilot asks for when it rolls to a bank angle")

src/main/java/dev/lumareth/improvedAerodynamics/flight/CursorPilot.java

@@ -53,6 +53,14 @@ final class CursorPilot {
         // Cursor as angles from the reticle: sideways (positive right) and up, both through any 270 degree cone
         double sideways = Math.atan2(aim.cr(), aim.cf());
         double vertical = Math.atan2(aim.cu(), Math.hypot(aim.cf(), aim.cr()));
+        // Deadzone around the reticle: shrink the cursor offset by its radius, direction kept
+        double offset = Math.hypot(sideways, vertical);
+        double deadzone = Math.toRadians(CursorAimConfig.DEADZONE_DEGREES.get());
+        if (offset > 1.0E-9) {
+            double scale = Math.max(0.0, offset - deadzone) / offset;
+            sideways *= scale;
+            vertical *= scale;
+        }
         double lateral = saturate(sideways / fullAngle);
         double blend = smoothstep(Math.abs(sideways), FINE_START, FINE_END);