* Performance Changes:

* Moves Entity Updates into a seperate thread, allowing for OpenSim to utilize a computers CPU more effectively in return for potentially greater user and prim capacity.
* Removes an expensive Sqrt call performed during Update on each object. This should lower CPU requirements for high-prim regions with physics enabled.
* MXP Changes: Centers the region around 0,0 for primitives instead of 128,128. Prim display should now look more correct for MXP viewers.

OpenSim/Framework/Util.cs

@@ -88,6 +88,21 @@ namespace OpenSim.Framework
             return Math.Sqrt(dx * dx + dy * dy + dz * dz);
         }
 
+        /// <summary>
+        /// Returns true if the distance beween A and B is less than amount. Significantly faster than GetDistanceTo since it eliminates the Sqrt.
+        /// </summary>
+        /// <param name="a"></param>
+        /// <param name="b"></param>
+        /// <param name="amount"></param>
+        /// <returns></returns>
+        public static bool DistanceLessThan(Vector3 a, Vector3 b, double amount)
+        {
+            float dx = a.X - b.X;
+            float dy = a.Y - b.Y;
+            float dz = a.Z - b.Z;
+            return (dx*dx + dy*dy + dz*dz) < (amount*amount);           
+        }
+
         /// <summary>
         /// Get the magnitude of a 3d vector
         /// </summary>