hierarchy rework

fixed swap

Scripts/Elements/Dirt.cs

@@ -12,14 +12,8 @@ public class Dirt : Solid {
     public override bool Update(int currentFrame) {
         if (!base.Update(currentFrame)) return false;
 
-        Vector2I freePos = Check(this, Vector2I.Down + Vector2I.Right);
-
-        if (freePos != Vector2I.Zero) { // diagonally right
-            Level.Swap(this, freePos);
-            return true;
-        }
+        Tick();
 
         return true; // not necessarily end, subclasses could do some more things
     }
-
 }