If an avatar is sitting, send out position updates to clients for any change, not just those outside the usual tolerances.

This is to allow small adjustments of less than 0.05m in functions such as llSetPrimitiveLinkParams() to work
This is another fix for http://opensimulator.org/mantis/view.php?id=7044
Extends regression test for this case.

OpenSim/Region/Framework/Scenes/Scene.cs

@@ -1495,7 +1495,7 @@ namespace OpenSim.Region.Framework.Scenes
                     // Objects queue their updates onto all scene presences
                     if (Frame % m_update_objects == 0)
                         m_sceneGraph.UpdateObjectGroups();
-    
+
                     // Run through all ScenePresences looking for updates
                     // Presence updates and queued object updates for each presence are sent to clients
                     if (Frame % m_update_presences == 0)

OpenSim/Region/Framework/Scenes/ScenePresence.cs

@@ -3084,9 +3084,19 @@ namespace OpenSim.Region.Framework.Scenes
                 if (Appearance.AvatarSize != m_lastSize && !IsLoggingIn)
                     SendAvatarDataToAllAgents();
 
-                if (!Rotation.ApproxEquals(m_lastRotation, ROTATION_TOLERANCE) ||
-                    !Velocity.ApproxEquals(m_lastVelocity, VELOCITY_TOLERANCE) ||
-                    !m_pos.ApproxEquals(m_lastPosition, POSITION_TOLERANCE))
+                // Allow any updates for sitting avatars to that llSetPrimitiveLinkParams() can work for very
+                // small increments (e.g. sit position adjusters).  An alternative may be to eliminate the tolerance
+                // checks on all updates but the ramifications of this would need careful consideration.
+                bool updateClients 
+                    = IsSatOnObject && (Rotation != m_lastRotation || Velocity != m_lastVelocity || m_pos != m_lastPosition);
+
+                if (!updateClients)
+                    updateClients 
+                        = !Rotation.ApproxEquals(m_lastRotation, ROTATION_TOLERANCE) 
+                            || !Velocity.ApproxEquals(m_lastVelocity, VELOCITY_TOLERANCE)
+                            || !m_pos.ApproxEquals(m_lastPosition, POSITION_TOLERANCE);
+
+                if (updateClients)
                 {
                     SendTerseUpdateToAllClients();
 

OpenSim/Region/ScriptEngine/Shared/Tests/LSL_ApiAvatarTests.cs

@@ -77,14 +77,21 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             m_engine.AddRegion(m_scene);
         }
 
+        /// <summary>
+        /// Test llSetLinkPrimtiveParams for agents.
+        /// </summary>
+        /// <remarks>
+        /// Also testing entity updates here as well.  Possibly that's putting 2 different concerns into one test and
+        /// this should be separated.
+        /// </remarks>
         [Test]
         public void TestllSetLinkPrimitiveParamsForAgent()
         {
             TestHelpers.InMethod();
+//            TestHelpers.EnableLogging();
 
             UUID userId = TestHelpers.ParseTail(0x1);
 
-            new SceneHelpers().SetupScene();
             SceneObjectPart part = SceneHelpers.AddSceneObject(m_scene).RootPart;
             part.RotationOffset = new Quaternion(0.7071068f, 0, 0, 0.7071068f);
 
@@ -99,12 +106,29 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
 
             sp.HandleAgentRequestSit(sp.ControllingClient, sp.UUID, part.UUID, Vector3.Zero);
 
+            int entityUpdates = 0;
+            ((TestClient)sp.ControllingClient).OnReceivedEntityUpdate += (entity, flags) => { if (entity is ScenePresence) { entityUpdates++; }};
+
             // Test position
             {
                 Vector3 newPos = new Vector3(1, 2, 3);
                 apiGrp1.llSetLinkPrimitiveParams(2, new LSL_Types.list(ScriptBaseClass.PRIM_POSITION, newPos));
 
                 Assert.That(sp.OffsetPosition, Is.EqualTo(newPos));
+
+                m_scene.Update(1);
+                Assert.That(entityUpdates, Is.EqualTo(1));
+            }
+
+            // Test small reposition
+            {
+                Vector3 newPos = new Vector3(1.001f, 2, 3);
+                apiGrp1.llSetLinkPrimitiveParams(2, new LSL_Types.list(ScriptBaseClass.PRIM_POSITION, newPos));
+
+                Assert.That(sp.OffsetPosition, Is.EqualTo(newPos));
+
+                m_scene.Update(1);
+                Assert.That(entityUpdates, Is.EqualTo(2));
             }
 
             // Test world rotation
@@ -114,6 +138,9 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
 
                 Assert.That(
                     sp.Rotation, new QuaternionToleranceConstraint(part.GetWorldRotation() * newRot, 0.000001));
+
+                m_scene.Update(1);
+                Assert.That(entityUpdates, Is.EqualTo(3));
             }
 
             // Test local rotation
@@ -123,6 +150,9 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
 
                 Assert.That(
                     sp.Rotation, new QuaternionToleranceConstraint(newRot, 0.000001));
+
+                m_scene.Update(1);
+                Assert.That(entityUpdates, Is.EqualTo(4));
             }
         }
     }

OpenSim/Tests/Common/Mock/TestClient.cs

@@ -62,6 +62,7 @@ namespace OpenSim.Tests.Common.Mock
         public event Action<RegionInfo, Vector3, Vector3> OnReceivedMoveAgentIntoRegion;
         public event Action<ulong, IPEndPoint> OnTestClientInformClientOfNeighbour;
         public event TestClientOnSendRegionTeleportDelegate OnTestClientSendRegionTeleport;
+        public event Action<ISceneEntity, PrimUpdateFlags> OnReceivedEntityUpdate;
         public event Action<GridInstantMessage> OnReceivedInstantMessage;
         public event Action<UUID> OnReceivedSendRebakeAvatarTextures;
 
@@ -685,6 +686,8 @@ namespace OpenSim.Tests.Common.Mock
 
         public void SendEntityUpdate(ISceneEntity entity, PrimUpdateFlags updateFlags)
         {
+            if (OnReceivedEntityUpdate != null)
+                OnReceivedEntityUpdate(entity, updateFlags);
         }
 
         public void ReprioritizeUpdates()