diff --git a/src/DotRecast.Detour.Dynamic/DynamicTileCheckpoint.cs b/src/DotRecast.Detour.Dynamic/DynamicTileCheckpoint.cs
index a1626c8..e7ebb26 100644
--- a/src/DotRecast.Detour.Dynamic/DynamicTileCheckpoint.cs
+++ b/src/DotRecast.Detour.Dynamic/DynamicTileCheckpoint.cs
@@ -34,8 +34,7 @@ namespace DotRecast.Detour.Dynamic
 
         private RcHeightfield Clone(RcHeightfield source)
         {
-            RcHeightfield clone = new RcHeightfield(source.width, source.height, source.bmin, source.bmax, source.cs,
-                source.ch, source.borderSize);
+            RcHeightfield clone = new RcHeightfield(source.width, source.height, source.bmin, source.bmax, source.cs, source.ch, source.borderSize);
             for (int z = 0, pz = 0; z < source.height; z++, pz += source.width)
             {
                 for (int x = 0; x < source.width; x++)
diff --git a/src/DotRecast.Recast.Demo/Tools/TileTool.cs b/src/DotRecast.Recast.Demo/Tools/TileTool.cs
index 2f35136..7d13215 100644
--- a/src/DotRecast.Recast.Demo/Tools/TileTool.cs
+++ b/src/DotRecast.Recast.Demo/Tools/TileTool.cs
@@ -4,7 +4,6 @@ using DotRecast.Recast.DemoTool;
 using DotRecast.Recast.DemoTool.Tools;
 using ImGuiNET;
 using static DotRecast.Recast.Demo.Draw.DebugDraw;
-using static DotRecast.Recast.Demo.Draw.DebugDrawPrimitives;
 
 namespace DotRecast.Recast.Demo.Tools;
 
@@ -50,14 +49,16 @@ public class TileTool : IRcTool
         _hitPos = p;
 
         var sample = _impl.GetSample();
-        if (null != sample)
+        if (null == sample)
+            return;
+
+        if (shift)
         {
-            if (shift)
-            {
-            }
-            else
-            {
-            }
+            _impl.RemoveTile(_hitPos);
+        }
+        else
+        {
+            _impl.BuildTile(_hitPos);
         }
     }
 
@@ -76,23 +77,24 @@ public class TileTool : IRcTool
         {
             var bmin = geom.GetMeshBoundsMin();
             var bmax = geom.GetMeshBoundsMax();
-            
+
             var settings = sample.GetSettings();
             var s = settings.agentRadius;
+            
             float ts = settings.tileSize * settings.cellSize;
             int tx = (int)((_hitPos.x - bmin[0]) / ts);
             int ty = (int)((_hitPos.z - bmin[2]) / ts);
 
             RcVec3f lastBuiltTileBmin = RcVec3f.Zero;
             RcVec3f lastBuiltTileBmax = RcVec3f.Zero;
-            
-            lastBuiltTileBmin[0] = bmin[0] + tx*ts;
+
+            lastBuiltTileBmin[0] = bmin[0] + tx * ts;
             lastBuiltTileBmin[1] = bmin[1];
-            lastBuiltTileBmin[2] = bmin[2] + ty*ts;
-	
-            lastBuiltTileBmax[0] = bmin[0] + (tx+1)*ts;
+            lastBuiltTileBmin[2] = bmin[2] + ty * ts;
+
+            lastBuiltTileBmax[0] = bmin[0] + (tx + 1) * ts;
             lastBuiltTileBmax[1] = bmax[1];
-            lastBuiltTileBmax[2] = bmin[2] + (ty+1)*ts;
+            lastBuiltTileBmax[2] = bmin[2] + (ty + 1) * ts;
 
             dd.DebugDrawCross(_hitPos.x, _hitPos.y + 0.1f, _hitPos.z, s, DuRGBA(0, 0, 0, 128), 2.0f);
             dd.DebugDrawBoxWire(
diff --git a/src/DotRecast.Recast.DemoTool/Tools/TileToolImpl.cs b/src/DotRecast.Recast.DemoTool/Tools/TileToolImpl.cs
index ea9a936..8c2c76c 100644
--- a/src/DotRecast.Recast.DemoTool/Tools/TileToolImpl.cs
+++ b/src/DotRecast.Recast.DemoTool/Tools/TileToolImpl.cs
@@ -1,4 +1,6 @@
-namespace DotRecast.Recast.DemoTool.Tools
+using DotRecast.Core;
+
+namespace DotRecast.Recast.DemoTool.Tools
 {
     public class TileToolImpl : ISampleTool
     {
@@ -18,5 +20,41 @@
         {
             return _sample;
         }
+
+        public void BuildTile(RcVec3f pos)
+        {
+            var settings = _sample.GetSettings();
+            var geom = _sample.GetInputGeom();
+            var navMesh = _sample.GetNavMesh();
+            
+            float ts = settings.tileSize * settings.cellSize;
+            
+            var bmin = geom.GetMeshBoundsMin();
+
+            int tx = (int)((pos.x - bmin[0]) / ts);
+            int ty = (int)((pos.z - bmin[2]) / ts);
+
+            var tileRef = navMesh.GetTileRefAt(tx, ty, 0);
+            navMesh.RemoveTile(tileRef); 
+            
+            navMesh.AddTile()
+        }
+
+        public void RemoveTile(RcVec3f pos)
+        {
+            var settings = _sample.GetSettings();
+            var geom = _sample.GetInputGeom();
+            var navMesh = _sample.GetNavMesh();
+            
+            float ts = settings.tileSize * settings.cellSize;
+            
+            var bmin = geom.GetMeshBoundsMin();
+
+            int tx = (int)((pos.x - bmin[0]) / ts);
+            int ty = (int)((pos.z - bmin[2]) / ts);
+
+            var tileRef = navMesh.GetTileRefAt(tx, ty, 0);
+            navMesh.RemoveTile(tileRef);
+        }
     }
 }
\ No newline at end of file