Fix llGetLinkPrimParams for PRIM_POS_LOCAL for child prims whether in scene or attachments.

Return relative position to root prim rather than 0,0,0.
Should fix same issue with llGetLocalPos()
http://opensimulator.org/mantis/view.php?id=5951

OpenSim/Region/Framework/Scenes/SceneObjectPart.cs

@@ -125,12 +125,14 @@ namespace OpenSim.Region.Framework.Scenes
         private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
 
         /// <value>
-        /// Is this sop a root part?
+        /// Is this a root part?
         /// </value>
-        
+        /// <remarks>
+        /// This will return true even if the whole object is attached to an avatar.
+        /// </remarks>
         public bool IsRoot 
         {
-           get { return ParentGroup.RootPart == this; } 
+            get { return ParentGroup.RootPart == this; } 
         }
 
         #region Fields
@@ -1112,6 +1114,14 @@ namespace OpenSim.Region.Framework.Scenes
             }
         }
 
+        /// <summary>
+        /// The parent ID of this part.
+        /// </summary>
+        /// <remarks>
+        /// If this is a root part which is not attached to an avatar then the value will be 0.
+        /// If this is a root part which is attached to an avatar then the value is the local id of that avatar.
+        /// If this is a child part then the value is the local ID of the root part.
+        /// </remarks>
         public uint ParentID
         {
             get { return _parentID; }

OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs

@@ -2022,27 +2022,28 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
         protected LSL_Vector GetPartLocalPos(SceneObjectPart part)
         {
             m_host.AddScriptLPS(1);
+
+            Vector3 pos;
+
             if (part.ParentID == 0)
             {
-                return new LSL_Vector(part.AbsolutePosition.X,
+                pos = part.AbsolutePosition;
-                                      part.AbsolutePosition.Y,
-                                      part.AbsolutePosition.Z);
             }
             else
             {
-                if (m_host.IsRoot)
+                if (part.IsRoot)
                 {
-                    return new LSL_Vector(m_host.AttachedPos.X,
+                    pos = part.AttachedPos;
-                                          m_host.AttachedPos.Y,
-                                          m_host.AttachedPos.Z);
                 }
                 else
                 {
-                    return new LSL_Vector(part.OffsetPosition.X,
+                    pos = part.OffsetPosition;
-                                          part.OffsetPosition.Y,
-                                          part.OffsetPosition.Z);
                 }
             }
+
+//            m_log.DebugFormat("[LSL API]: Returning {0} in GetPartLocalPos()", pos);
+
+            return new LSL_Vector(pos.X, pos.Y, pos.Z);
         }
 
         public void llSetRot(LSL_Rotation rot)