much better

src/Poe2Trade.Navigation/WorldMap.cs

@@ -34,18 +34,15 @@ public class WorldMap : IDisposable
         var sw = Stopwatch.StartNew();
         _frameCount++;
 
-        // Noise gate: skip frames with too many wall pixels (waypoint glow, effects)
-        // But NOT during warmup or re-bootstrap — we need to stitch something to get started
-        var wallPixels = Cv2.CountNonZero(wallMask);
-        var totalPixels = wallMask.Width * wallMask.Height;
-        var density = (double)wallPixels / totalPixels;
-        var isNoisy = density > _config.WallMaxDensity;
         var needsBootstrap = _frameCount <= _config.WarmupFrames || _consecutiveMatchFails >= 30;
 
-        if (isNoisy && !needsBootstrap)
+        // Block-based noise filter: zero out 50×50 blocks with >25% wall density
+        // Removes localized glow (waypoints, effects) while preserving real walls
+        var cleanFraction = FilterNoisyBlocks(wallMask, classifiedMat);
+        if (cleanFraction < 0.25 && !needsBootstrap)
         {
-            Log.Information("Noise gate: {Density:P1} wall density ({Pixels} px), skipping ({Ms:F1}ms)",
-                density, wallPixels, sw.Elapsed.TotalMilliseconds);
+            Log.Information("Noise filter: {Clean:P0} clean, skipping ({Ms:F1}ms)",
+                cleanFraction, sw.Elapsed.TotalMilliseconds);
             return _position;
         }
 
@@ -260,6 +257,46 @@ public class WorldMap : IDisposable
         }
     }
 
+    /// <summary>
+    /// Zero out 50×50 blocks where wall density exceeds 25%.
+    /// Modifies wallMask and classifiedMat in-place.
+    /// Returns fraction of blocks that are clean (0.0–1.0).
+    /// </summary>
+    private static double FilterNoisyBlocks(Mat wallMask, Mat classifiedMat,
+        int blockSize = 50, double blockMaxDensity = 0.25)
+    {
+        var rows = wallMask.Rows;
+        var cols = wallMask.Cols;
+        var totalBlocks = 0;
+        var cleanBlocks = 0;
+
+        for (var by = 0; by < rows; by += blockSize)
+        for (var bx = 0; bx < cols; bx += blockSize)
+        {
+            var bw = Math.Min(blockSize, cols - bx);
+            var bh = Math.Min(blockSize, rows - by);
+            totalBlocks++;
+
+            var blockRect = new Rect(bx, by, bw, bh);
+            using var blockRoi = new Mat(wallMask, blockRect);
+            var wallCount = Cv2.CountNonZero(blockRoi);
+
+            if ((double)wallCount / (bw * bh) > blockMaxDensity)
+            {
+                // Zero out this noisy block in both mats
+                blockRoi.SetTo(Scalar.Black);
+                using var classBlock = new Mat(classifiedMat, blockRect);
+                classBlock.SetTo(Scalar.Black);
+            }
+            else
+            {
+                cleanBlocks++;
+            }
+        }
+
+        return totalBlocks > 0 ? (double)cleanBlocks / totalBlocks : 1.0;
+    }
+
     public (double dirX, double dirY)? FindNearestUnexplored(MapPosition pos, int searchRadius = 200)
     {
         var cx = (int)Math.Round(pos.X);