Parameterizes the view distance used to compute and manage

child agents in neighbor regions. This means you can extend
the view on a simulator beyond the default 3x3 regions.

This uses a region default draw distance and should be
replaced at some point by the avatar specified draw distance.
That will require more careful, dynamic recomputation of child
agents every time the draw distance changes.

WARNING: this is experimental and has known instabilities. specifically
all regions "within site" should be running the same default draw distance
or agents will not be closed correctly.

6 files changed, 73 insertions, 21 deletions

diff --git a/OpenSim/Framework/Util.cs b/OpenSim/Framework/Util.cs
index 533e53a..5a5046e 100644
--- a/OpenSim/Framework/Util.cs
+++ b/OpenSim/Framework/Util.cs
@@ -459,10 +459,17 @@ namespace OpenSim.Framework
         /// <param name="oldy">Old region y-coord</param>
         /// <param name="newy">New region y-coord</param>
         /// <returns></returns>        
-        public static bool IsOutsideView(uint oldx, uint newx, uint oldy, uint newy)
+        public static bool IsOutsideView(float drawdist, uint oldx, uint newx, uint oldy, uint newy)
         {
-            // Eventually this will be a function of the draw distance / camera position too.
-            return (((int)Math.Abs((int)(oldx - newx)) > 1) || ((int)Math.Abs((int)(oldy - newy)) > 1));
+            int dd = (int)((drawdist + Constants.RegionSize - 1) / Constants.RegionSize);
+
+            int startX = (int)oldx - dd;
+            int startY = (int)oldy - dd;
+
+            int endX = (int)oldx + dd;
+            int endY = (int)oldy + dd;
+
+            return (newx < startX || endX < newx || newy < startY || endY < newy);
         }
 
         public static string FieldToString(byte[] bytes)
diff --git a/OpenSim/Region/CoreModules/Framework/EntityTransfer/EntityTransferModule.cs b/OpenSim/Region/CoreModules/Framework/EntityTransfer/EntityTransferModule.cs
index 98aa563..95c771e 100644
--- a/OpenSim/Region/CoreModules/Framework/EntityTransfer/EntityTransferModule.cs
+++ b/OpenSim/Region/CoreModules/Framework/EntityTransfer/EntityTransferModule.cs
@@ -318,7 +318,7 @@ namespace OpenSim.Region.CoreModules.Framework.EntityTransfer
                     agentCircuit.Id0 = currentAgentCircuit.Id0;
                 }
 
-                if (NeedsNewAgent(oldRegionX, newRegionX, oldRegionY, newRegionY))
+                if (NeedsNewAgent(sp.DrawDistance, oldRegionX, newRegionX, oldRegionY, newRegionY))
                 {
                     // brand new agent, let's create a new caps seed
                     agentCircuit.CapsPath = CapsUtil.GetRandomCapsObjectPath();
@@ -336,7 +336,7 @@ namespace OpenSim.Region.CoreModules.Framework.EntityTransfer
                 // OK, it got this agent. Let's close some child agents
                 sp.CloseChildAgents(newRegionX, newRegionY);
                 IClientIPEndpoint ipepClient;  
-                if (NeedsNewAgent(oldRegionX, newRegionX, oldRegionY, newRegionY))
+                if (NeedsNewAgent(sp.DrawDistance, oldRegionX, newRegionX, oldRegionY, newRegionY))
                 {
                     //sp.ControllingClient.SendTeleportProgress(teleportFlags, "Creating agent...");
                     #region IP Translation for NAT
@@ -447,7 +447,7 @@ namespace OpenSim.Region.CoreModules.Framework.EntityTransfer
 
                 // Finally, let's close this previously-known-as-root agent, when the jump is outside the view zone
 
-                if (NeedsClosing(oldRegionX, newRegionX, oldRegionY, newRegionY, reg))
+                if (NeedsClosing(sp.DrawDistance, oldRegionX, newRegionX, oldRegionY, newRegionY, reg))
                 {
                     Thread.Sleep(5000);
                     sp.Close();
@@ -521,14 +521,14 @@ namespace OpenSim.Region.CoreModules.Framework.EntityTransfer
             return region;
         }
 
-        protected virtual bool NeedsNewAgent(uint oldRegionX, uint newRegionX, uint oldRegionY, uint newRegionY)
+        protected virtual bool NeedsNewAgent(float drawdist, uint oldRegionX, uint newRegionX, uint oldRegionY, uint newRegionY)
         {
-            return Util.IsOutsideView(oldRegionX, newRegionX, oldRegionY, newRegionY);
+            return Util.IsOutsideView(drawdist, oldRegionX, newRegionX, oldRegionY, newRegionY);
         }
 
-        protected virtual bool NeedsClosing(uint oldRegionX, uint newRegionX, uint oldRegionY, uint newRegionY, GridRegion reg)
+        protected virtual bool NeedsClosing(float drawdist, uint oldRegionX, uint newRegionX, uint oldRegionY, uint newRegionY, GridRegion reg)
         {
-            return Util.IsOutsideView(oldRegionX, newRegionX, oldRegionY, newRegionY);
+            return Util.IsOutsideView(drawdist, oldRegionX, newRegionX, oldRegionY, newRegionY);
         }
 
         protected virtual bool IsOutsideRegion(Scene s, Vector3 pos)
@@ -1045,7 +1045,7 @@ namespace OpenSim.Region.CoreModules.Framework.EntityTransfer
 
             if (m_regionInfo != null)
             {
-                neighbours = RequestNeighbours(sp.Scene, m_regionInfo.RegionLocX, m_regionInfo.RegionLocY);
+                neighbours = RequestNeighbours(sp, m_regionInfo.RegionLocX, m_regionInfo.RegionLocY);
             }
             else
             {
@@ -1272,8 +1272,9 @@ namespace OpenSim.Region.CoreModules.Framework.EntityTransfer
         /// <param name="pRegionLocX"></param>
         /// <param name="pRegionLocY"></param>
         /// <returns></returns>        
-        protected List<GridRegion> RequestNeighbours(Scene pScene, uint pRegionLocX, uint pRegionLocY)
+        protected List<GridRegion> RequestNeighbours(ScenePresence avatar, uint pRegionLocX, uint pRegionLocY)
         {
+            Scene pScene = avatar.Scene;
             RegionInfo m_regionInfo = pScene.RegionInfo;
 
             Border[] northBorders = pScene.NorthBorders.ToArray();
@@ -1281,10 +1282,24 @@ namespace OpenSim.Region.CoreModules.Framework.EntityTransfer
             Border[] eastBorders = pScene.EastBorders.ToArray();
             Border[] westBorders = pScene.WestBorders.ToArray();
 
-            // Legacy one region.  Provided for simplicity while testing the all inclusive method in the else statement.
+            // Leaving this as a "megaregions" computation vs "non-megaregions" computation; it isn't
+            // clear what should be done with a "far view" given that megaregions already extended the
+            // view to include everything in the megaregion
             if (northBorders.Length <= 1 && southBorders.Length <= 1 && eastBorders.Length <= 1 && westBorders.Length <= 1)
             {
-                return pScene.GridService.GetNeighbours(m_regionInfo.ScopeID, m_regionInfo.RegionID);
+                int dd = avatar.DrawDistance < Constants.RegionSize ? (int)Constants.RegionSize : (int)avatar.DrawDistance;
+
+                int startX = (int)pRegionLocX * (int)Constants.RegionSize - dd + (int)(Constants.RegionSize/2);
+                int startY = (int)pRegionLocY * (int)Constants.RegionSize - dd + (int)(Constants.RegionSize/2);
+
+                int endX = (int)pRegionLocX * (int)Constants.RegionSize + dd + (int)(Constants.RegionSize/2);
+                int endY = (int)pRegionLocY * (int)Constants.RegionSize + dd + (int)(Constants.RegionSize/2);
+
+                List<GridRegion> neighbours =
+                    avatar.Scene.GridService.GetRegionRange(m_regionInfo.ScopeID, startX, endX, startY, endY);
+
+                neighbours.RemoveAll(delegate(GridRegion r) { return r.RegionID == m_regionInfo.RegionID; });
+                return neighbours;
             }
             else
             {
diff --git a/OpenSim/Region/CoreModules/Framework/EntityTransfer/HGEntityTransferModule.cs b/OpenSim/Region/CoreModules/Framework/EntityTransfer/HGEntityTransferModule.cs
index 35dcd95..79e76b4 100644
--- a/OpenSim/Region/CoreModules/Framework/EntityTransfer/HGEntityTransferModule.cs
+++ b/OpenSim/Region/CoreModules/Framework/EntityTransfer/HGEntityTransferModule.cs
@@ -130,9 +130,9 @@ namespace OpenSim.Region.CoreModules.Framework.EntityTransfer
             return region;
         }
 
-        protected override bool NeedsClosing(uint oldRegionX, uint newRegionX, uint oldRegionY, uint newRegionY, GridRegion reg)
+        protected override bool NeedsClosing(float drawdist, uint oldRegionX, uint newRegionX, uint oldRegionY, uint newRegionY, GridRegion reg)
         {
-            if (base.NeedsClosing(oldRegionX, newRegionX, oldRegionY, newRegionY, reg))
+            if (base.NeedsClosing(drawdist, oldRegionX, newRegionX, oldRegionY, newRegionY, reg))
                 return true;
 
             int flags = m_aScene.GridService.GetRegionFlags(m_aScene.RegionInfo.ScopeID, reg.RegionID);
diff --git a/OpenSim/Region/Framework/Scenes/Scene.cs b/OpenSim/Region/Framework/Scenes/Scene.cs
index ee1e0be..7def7e9 100644
--- a/OpenSim/Region/Framework/Scenes/Scene.cs
+++ b/OpenSim/Region/Framework/Scenes/Scene.cs
@@ -83,6 +83,13 @@ namespace OpenSim.Region.Framework.Scenes
         public bool m_useFlySlow;
         public bool m_usePreJump;
         public bool m_seeIntoRegionFromNeighbor;
+
+        protected float m_defaultDrawDistance = 255.0f;
+        public float DefaultDrawDistance 
+        {
+            get { return m_defaultDrawDistance; }
+        }
+        
         // TODO: need to figure out how allow client agents but deny
         // root agents when ACL denies access to root agent
         public bool m_strictAccessControl = true;
@@ -627,6 +634,8 @@ namespace OpenSim.Region.Framework.Scenes
                 //
                 IConfig startupConfig = m_config.Configs["Startup"];
 
+                m_defaultDrawDistance = startupConfig.GetFloat("DefaultDrawDistance",m_defaultDrawDistance);
+                
                 //Animation states
                 m_useFlySlow = startupConfig.GetBoolean("enableflyslow", false);
                 // TODO: Change default to true once the feature is supported
diff --git a/OpenSim/Region/Framework/Scenes/ScenePresence.cs b/OpenSim/Region/Framework/Scenes/ScenePresence.cs
index 51b8dcc..9e9481e 100644
--- a/OpenSim/Region/Framework/Scenes/ScenePresence.cs
+++ b/OpenSim/Region/Framework/Scenes/ScenePresence.cs
@@ -626,7 +626,7 @@ namespace OpenSim.Region.Framework.Scenes
                 Utils.LongToUInts(handle, out x, out y);
                 x = x / Constants.RegionSize;
                 y = y / Constants.RegionSize;
-                if (Util.IsOutsideView(x, Scene.RegionInfo.RegionLocX, y, Scene.RegionInfo.RegionLocY))
+                if (Util.IsOutsideView(DrawDistance, x, Scene.RegionInfo.RegionLocX, y, Scene.RegionInfo.RegionLocY))
                 {
                     old.Add(handle);
                 }
@@ -700,6 +700,7 @@ namespace OpenSim.Region.Framework.Scenes
         
         private ScenePresence(IClientAPI client, Scene world, RegionInfo reginfo) : this()
         {
+            m_DrawDistance = world.DefaultDrawDistance;
             m_rootRegionHandle = reginfo.RegionHandle;
             m_controllingClient = client;
             m_firstname = m_controllingClient.FirstName;
@@ -1279,7 +1280,11 @@ namespace OpenSim.Region.Framework.Scenes
             m_CameraUpAxis = agentData.CameraUpAxis;
 
             // The Agent's Draw distance setting
-            m_DrawDistance = agentData.Far;
+            // When we get to the point of re-computing neighbors everytime this
+            // changes, then start using the agent's drawdistance rather than the 
+            // region's draw distance.
+            // m_DrawDistance = agentData.Far;
+            m_DrawDistance = Scene.DefaultDrawDistance;
 
             // Check if Client has camera in 'follow cam' or 'build' mode.
             Vector3 camdif = (Vector3.One * m_bodyRot - Vector3.One * CameraRotation);
@@ -2913,7 +2918,7 @@ namespace OpenSim.Region.Framework.Scenes
 
                         //m_log.Debug("---> x: " + x + "; newx:" + newRegionX + "; Abs:" + (int)Math.Abs((int)(x - newRegionX)));
                         //m_log.Debug("---> y: " + y + "; newy:" + newRegionY + "; Abs:" + (int)Math.Abs((int)(y - newRegionY)));
-                        if (Util.IsOutsideView(x, newRegionX, y, newRegionY))
+                        if (Util.IsOutsideView(DrawDistance, x, newRegionX, y, newRegionY))
                         {
                             byebyeRegions.Add(handle);
                         }
@@ -2989,7 +2994,12 @@ namespace OpenSim.Region.Framework.Scenes
 
             Vector3 offset = new Vector3(shiftx, shifty, 0f);
 
-            m_DrawDistance = cAgentData.Far;
+            // When we get to the point of re-computing neighbors everytime this
+            // changes, then start using the agent's drawdistance rather than the 
+            // region's draw distance.
+            // m_DrawDistance = cAgentData.Far;
+            m_DrawDistance = Scene.DefaultDrawDistance;
+            
             if (cAgentData.Position != new Vector3(-1f, -1f, -1f)) // UGH!!
                 m_pos = cAgentData.Position + offset;
 
@@ -3139,7 +3149,11 @@ namespace OpenSim.Region.Framework.Scenes
             m_CameraLeftAxis = cAgent.LeftAxis;
             m_CameraUpAxis = cAgent.UpAxis;
 
-            m_DrawDistance = cAgent.Far;
+            // When we get to the point of re-computing neighbors everytime this
+            // changes, then start using the agent's drawdistance rather than the 
+            // region's draw distance.
+            // m_DrawDistance = cAgent.Far;
+            m_DrawDistance = Scene.DefaultDrawDistance;
 
             if ((cAgent.Throttles != null) && cAgent.Throttles.Length > 0)
                 ControllingClient.SetChildAgentThrottle(cAgent.Throttles);
diff --git a/bin/OpenSimDefaults.ini b/bin/OpenSimDefaults.ini
index 475d4a0..96ffb7e 100644
--- a/bin/OpenSimDefaults.ini
+++ b/bin/OpenSimDefaults.ini
@@ -94,6 +94,13 @@
     ; Warning!  Don't use this with regions that have existing content!, This will likely break them
     CombineContiguousRegions = false
 
+    ; Extend the region's draw distance; 255m is the default which includes
+    ; one neighbor on each side of the current region, 767m would go three
+    ; neighbors on each side for a total of 49 regions in view. Warning, unless
+    ; all the regions have the same drawdistance, you will end up with strange
+    ; effects because the agents that get closed may be inconsistent.
+    ; DefaultDrawDistance = 255.0
+
     ; If you have only one region in an instance, or to avoid the many bugs
     ; that you can trigger in modules by restarting a region, set this to
     ; true to make the entire instance exit instead of restarting the region.