Add "show borders" command to show the borders of a region.

This is relevant to mega-regions where the borders are very different to a regular region.
Also adds some method doc and other code comments.

OpenSim/Region/CoreModules/Framework/EntityTransfer/EntityTransferModule.cs

@@ -977,6 +977,10 @@ namespace OpenSim.Region.CoreModules.Framework.EntityTransfer
         {
             Scene scene = agent.Scene;
             Vector3 pos = agent.AbsolutePosition;
+
+//            m_log.DebugFormat(
+//                "[ENTITY TRANSFER MODULE]: Crossing agent {0} at pos {1} in {2}", agent.Name, pos, scene.Name);
+
             Vector3 newpos = new Vector3(pos.X, pos.Y, pos.Z);
             uint neighbourx = scene.RegionInfo.RegionLocX;
             uint neighboury = scene.RegionInfo.RegionLocY;

OpenSim/Region/Framework/Scenes/Border.cs

@@ -33,8 +33,7 @@ using OpenMetaverse;
 namespace OpenSim.Region.Framework.Scenes
 {
     public class Border
-    {
+    {       
-        
         /// <summary>
         /// Line perpendicular to the Direction Cardinal.  Z value is the 
         /// </summary>
@@ -81,6 +80,10 @@ namespace OpenSim.Region.Framework.Scenes
             TriggerRegionY = triggerRegionY;
         }
 
+        /// <summary>
+        /// Tests to see if the given position would cross this border.
+        /// </summary>
+        /// <returns></returns>
         public bool TestCross(Vector3 position)
         {
             bool result = false;

OpenSim/Region/Framework/Scenes/Scene.cs

@@ -2462,7 +2462,6 @@ namespace OpenSim.Region.Framework.Scenes
 
                 }
             }
-            
 
             return null;
         }

OpenSim/Region/Framework/Scenes/ScenePresence.cs

@@ -439,9 +439,9 @@ namespace OpenSim.Region.Framework.Scenes
                 {
                     m_pos = PhysicsActor.Position;
 
-                    //m_log.DebugFormat(
+//                    m_log.DebugFormat(
-                    //    "[SCENE PRESENCE]: Set position {0} for {1} in {2} via getting AbsolutePosition!",
+//                        "[SCENE PRESENCE]: Set position of {0} in {1} to {2} via getting AbsolutePosition!",
-                    //    m_pos, Name, Scene.RegionInfo.RegionName);
+//                        Name, Scene.Name, m_pos);
                 }
                 else
                 {
@@ -468,6 +468,9 @@ namespace OpenSim.Region.Framework.Scenes
             }
             set
             {
+//                m_log.DebugFormat("[SCENE PRESENCE]: Setting position of {0} in {1} to {2}", Name, Scene.Name, value);
+//                Util.PrintCallStack();
+
                 if (PhysicsActor != null)
                 {
                     try
@@ -831,6 +834,7 @@ namespace OpenSim.Region.Framework.Scenes
             // before the inventory is processed in MakeRootAgent. This fixes a race condition
             // related to the handling of attachments
             //m_scene.GetAvatarAppearance(ControllingClient, out Appearance);
+
             if (m_scene.TestBorderCross(pos, Cardinals.E))
             {
                 Border crossedBorder = m_scene.GetCrossedBorder(pos, Cardinals.E);
@@ -2747,6 +2751,10 @@ namespace OpenSim.Region.Framework.Scenes
 
                 if (!IsInTransit)
                 {
+//                    m_log.DebugFormat(
+//                        "[SCENE PRESENCE]: Testing border check for projected position {0} of {1} in {2}", 
+//                        pos2, Name, Scene.Name);
+
                     // Checks if where it's headed exists a region
                     bool needsTransit = false;
                     if (m_scene.TestBorderCross(pos2, Cardinals.W))

OpenSim/Region/OptionalModules/World/SceneCommands/SceneCommandsModule.cs

@@ -116,6 +116,37 @@ namespace OpenSim.Region.OptionalModules.Avatar.Attachments
                     + "If teleport   is true  then some extra teleport debug information is logged.\n"
                     + "If updates    is true  then any frame which exceeds double the maximum desired frame time is logged.",
                 HandleDebugSceneSetCommand);
+
+            scene.AddCommand(
+                "Regions", 
+                this, "show borders", "show borders", "Show border information for regions", HandleShowBordersCommand);
+        }
+
+        private void HandleShowBordersCommand(string module, string[] args)
+        {
+            StringBuilder sb = new StringBuilder();
+            sb.AppendFormat("Borders for {0}:\n", m_scene.Name);
+
+            ConsoleDisplayTable cdt = new ConsoleDisplayTable();
+            cdt.AddColumn("Cross Direction", 15);
+            cdt.AddColumn("Line", 34);
+            cdt.AddColumn("Trigger Region", 14);
+
+            foreach (Border b in m_scene.NorthBorders)
+                cdt.AddRow(b.CrossDirection, b.BorderLine, string.Format("{0}, {1}", b.TriggerRegionX, b.TriggerRegionY));
+
+            foreach (Border b in m_scene.EastBorders)
+                cdt.AddRow(b.CrossDirection, b.BorderLine, string.Format("{0}, {1}", b.TriggerRegionX, b.TriggerRegionY));
+
+            foreach (Border b in m_scene.SouthBorders)
+                cdt.AddRow(b.CrossDirection, b.BorderLine, string.Format("{0}, {1}", b.TriggerRegionX, b.TriggerRegionY));
+
+            foreach (Border b in m_scene.WestBorders)
+                cdt.AddRow(b.CrossDirection, b.BorderLine, string.Format("{0}, {1}", b.TriggerRegionX, b.TriggerRegionY));
+
+            cdt.AddToStringBuilder(sb);
+
+            MainConsole.Instance.Output(sb.ToString());
         }
 
         private void HandleDebugSceneGetCommand(string module, string[] args)

OpenSim/Region/RegionCombinerModule/RegionCombinerModule.cs

@@ -418,18 +418,17 @@ namespace OpenSim.Region.RegionCombinerModule
                         */
                     #endregion
 
-                    // If we're one region over +x y
+                    // If we're one region over +x y (i.e. root region is to the west)
                     //xxx
                     //xxy
                     //xxx
-
                     if (rootConn.PosX + rootConn.XEnd >= newConn.PosX && rootConn.PosY >= newConn.PosY)
                     {
                         connectedYN = DoWorkForOneRegionOverPlusXY(rootConn, newConn, scene);
                         break;
                     }
 
-                    // If we're one region over x +y
+                    // If we're one region over x +y (i.e. root region is to the south)
                     //xyx
                     //xxx
                     //xxx
@@ -439,7 +438,7 @@ namespace OpenSim.Region.RegionCombinerModule
                         break;
                     }
 
-                    // If we're one region over +x +y
+                    // If we're one region over +x +y (i.e. root region is to the south-west)
                     //xxy
                     //xxx
                     //xxx
@@ -649,7 +648,6 @@ namespace OpenSim.Region.RegionCombinerModule
             {
                 if (rootConn.RegionScene.EastBorders.Count == 1)// && conn.RegionScene.EastBorders.Count == 2)
                 {
-
                     rootConn.RegionScene.EastBorders[0].BorderLine.Z += (int)Constants.RegionSize;
 
                     lock (rootConn.RegionScene.NorthBorders)