Cannot place a tree on top of a tree

EduNetworkBuilder/Network.cs

@@ -502,6 +502,23 @@ namespace EduNetworkBuilder
             return null;
         }
 
+        public bool BlockedByTree(Point NetworkLocation)
+        {
+            NetworkDevice tDevice;
+            foreach (NetworkComponent tItem in NetComponents)
+            {
+                if (tItem is NetworkDevice)
+                {
+                    tDevice = (NetworkDevice)tItem;
+                    if (tDevice.GetNetType() != NetworkComponentType.tree) continue; //We only care about trees
+                    Rectangle myRec = tDevice.GetMyRectangle();
+                    if (myRec.Contains(NetworkLocation))
+                        return true;
+                }
+            }
+            return false;
+        }
+
         public NetworkLink LinkAtPosition(Point NetworkLocation)
         {
             NetworkLink tLink;

EduNetworkBuilder/NetworkBuilder.cs

@@ -1487,7 +1487,22 @@ namespace EduNetworkBuilder
                             NC = myNetwork.AddItem(NetworkComponentType.wrepeater, CenteredLocation);
                             break;
                         case "btnTree":
-                            NC = myNetwork.AddItem(NetworkComponentType.tree, CenteredLocation);
+                            bool CanDo = true;
+                            Point TopLeft = CenteredLocation;
+                            Point TopRight = new Point(TopLeft.X + myNetwork.itemsize, TopLeft.Y);
+                            Point BottomRight = new Point(TopLeft.X + myNetwork.itemsize, TopLeft.Y + myNetwork.itemsize);
+                            Point BottomLeft = new Point(TopLeft.X, TopLeft.Y + myNetwork.itemsize);
+                            if (myNetwork.BlockedByTree(ClickedLocation)) CanDo = false;
+                            if (myNetwork.BlockedByTree(TopLeft)) CanDo = false;
+                            if (myNetwork.BlockedByTree(TopRight)) CanDo = false;
+                            if (myNetwork.BlockedByTree(BottomRight)) CanDo = false;
+                            if (myNetwork.BlockedByTree(BottomLeft)) CanDo = false;
+                            if(CanDo)
+                                NC = myNetwork.AddItem(NetworkComponentType.tree, CenteredLocation);
+                            else
+                            {
+                                lblStatus.Text = NB.Translate("NB_TreePlacementError");
+                            }
                             break;
 
                     }

EduNetworkBuilder/Resources/languages/edustrings.resx

@@ -2033,4 +2033,8 @@
     <value>Add a tree to the network to block wireless signals</value>
     <comment>NB_BuildBtnTree = Add a tree to the network to block wireless signals</comment>
   </data>
+  <data name="NB_TreePlacementError" xml:space="preserve">
+    <value>Cannot place a tree on top of a tree.</value>
+    <comment>NB_TreePlacementError = Cannot place a tree on top of a tree.</comment>
+  </data>
 </root>