Version: 167.0.0

Co-authored-by: metalgearsloth <31366439+metalgearsloth@users.noreply.github.com>

MSBuild/Robust.Engine.Version.props

@@ -1,4 +1,4 @@
 <Project>
 
-    <!-- This file automatically reset by Tools/version.py -->
+    <!-- This file automatically reset by Tools/version.py -->
 

RELEASE-NOTES.md

@@ -54,6 +54,23 @@ END TEMPLATE-->
 *None yet*
 
 
+## 167.0.0
+
+### Breaking changes
+
+* Remove ComponentExtensions.
+* Remove ContainerHelpers.
+* Change some TransformSystem methods to fix clientside lerping.
+
+### Bugfixes
+
+* Fixed PVS bugs from dropped entity states.
+
+### Other
+
+* Add more joint debug asserts.
+
+
 ## 166.0.0
 
 ### Breaking changes

Robust.Client/GameObjects/EntitySystems/TransformSystem.Component.cs

@@ -1,51 +1,41 @@
 using System.Numerics;
+using Robust.Client.Player;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 using Robust.Shared.Maths;
 
 namespace Robust.Client.GameObjects;
 
 public sealed partial class TransformSystem
 {
-    public override void SetLocalPosition(TransformComponent xform, Vector2 value)
+    public override void SetLocalPosition(EntityUid uid, Vector2 value, TransformComponent? xform = null)
     {
-        xform.PrevPosition = xform._localPosition;
+        if (!XformQuery.Resolve(uid, ref xform))
+            return;
+
         xform.NextPosition = value;
-        xform.LerpParent = xform.ParentUid;
-        base.SetLocalPosition(xform, value);
-        ActivateLerp(xform);
+        ActivateLerp(uid, xform);
+        base.SetLocalPosition(uid, value, xform);
     }
 
-    public override void SetLocalPositionNoLerp(TransformComponent xform, Vector2 value)
+    public override void SetLocalRotation(EntityUid uid, Angle value, TransformComponent? xform = null)
     {
-        xform.NextPosition = null;
-        xform.LerpParent = EntityUid.Invalid;
-        base.SetLocalPositionNoLerp(xform, value);
+        if (!XformQuery.Resolve(uid, ref xform))
+            return;
+
+        xform.NextRotation = value;
+        ActivateLerp(uid, xform);
+        base.SetLocalRotation(uid, value, xform);
     }
 
-    public override void SetLocalRotationNoLerp(TransformComponent xform, Angle angle)
+    public override void SetLocalPositionRotation(EntityUid uid, Vector2 pos, Angle rot, TransformComponent? xform = null)
     {
-        xform.NextRotation = null;
-        xform.LerpParent = EntityUid.Invalid;
-        base.SetLocalRotationNoLerp(xform, angle);
-    }
+        if (!XformQuery.Resolve(uid, ref xform))
+            return;
 
-    public override void SetLocalRotation(TransformComponent xform, Angle angle)
-    {
-        xform.PrevRotation = xform._localRotation;
-        xform.NextRotation = angle;
-        xform.LerpParent = xform.ParentUid;
-        base.SetLocalRotation(xform, angle);
-        ActivateLerp(xform);
-    }
-
-    public override void SetLocalPositionRotation(TransformComponent xform, Vector2 pos, Angle rot)
-    {
-        xform.PrevPosition = xform._localPosition;
         xform.NextPosition = pos;
-        xform.PrevRotation = xform._localRotation;
         xform.NextRotation = rot;
-        xform.LerpParent = xform.ParentUid;
-        base.SetLocalPositionRotation(xform, pos, rot);
-        ActivateLerp(xform);
+        ActivateLerp(uid, xform);
+        base.SetLocalPositionRotation(uid, pos, rot, xform);
     }
 }

Robust.Client/GameObjects/EntitySystems/TransformSystem.cs

@@ -1,4 +1,3 @@
-using System;
 using System.Collections.Generic;
 using System.Numerics;
 using JetBrains.Annotations;
@@ -25,11 +24,6 @@ namespace Robust.Client.GameObjects
         private const float MinInterpolationDistance = 0.001f;
         private const float MinInterpolationDistanceSquared = MinInterpolationDistance * MinInterpolationDistance;
 
-        private const double MinInterpolationAngle = Math.PI / 720;
-
-        // 45 degrees.
-        private const double MaxInterpolationAngle = Math.PI / 4;
-
         [Dependency] private readonly IGameTiming _gameTiming = default!;
 
         // Only keep track of transforms actively lerping.
@@ -48,21 +42,77 @@ namespace Robust.Client.GameObjects
             _lerpingTransforms.Clear();
         }
 
-        public override void ActivateLerp(TransformComponent xform)
+        public override void ActivateLerp(EntityUid uid, TransformComponent xform)
         {
-            if (xform.ActivelyLerping)
+            // This lerping logic is pretty convoluted and generally assumes that the client does not mispredict.
+            // A more foolproof solution would be to just cache the coordinates at which any given entity was most
+            // recently rendered and using that as the lerp origin. However that'd require enumerating over all entities
+            // every tick which is pretty icky.
+
+            // The general considerations are:
+            // - If the client receives a server state for an entity moving from a->b and predicts nothing else, then it
+            //   should show the entity lerping.
+            // - If the client predicts an entity will move while already lerping due to a state-application, it should
+            //   clear the state's lerp, under the assumption that the client predicted the state and already rendered
+            //   the entity in the final position.
+            // - If the client predicts that an entity moves, then we only lerp if this is the first time that the tick
+            //   was predicted. I.e., we assume the entity was already rendered in it's final of that lerp.
+            // - If the client predicts that an entity should lerp twice in the same tick, then we need to combine them.
+            //   I.e. moving from a->b then b->c, the client should lerp from a->c.
+
+            // If the client predicts an entity moves while already lerping, it should clear the
+            // predict a->b, lerp a->b
+            // predicted a->b, then predict b->c. Lerp b->c
+            // predicted a->b, then predict b->c. Lerp b->c
+            // predicted a->b, predicted b->c, then predict c->d. Lerp c->d
+            // server state a->b, then predicted b->c, lerp b->c
+            // server state a->b, then predicted b->c, then predict d, lerp b->c
+
+            if (_gameTiming.ApplyingState)
+            {
+                if (xform.ActivelyLerping)
+                {
+                    // This should not happen, but can happen if some bad component state application code modifies an entity's coordinates.
+                    Log.Error($"Entity {(ToPrettyString(uid))} tried to lerp twice while applying component states.");
+                    return;
+                }
+
+                _lerpingTransforms.Add(xform);
+                xform.ActivelyLerping = true;
+                xform.PredictedLerp = false;
+                xform.LerpParent = xform.ParentUid;
+                xform.PrevRotation = xform._localRotation;
+                xform.PrevPosition = xform._localPosition;
+                xform.LastLerp = _gameTiming.CurTick;
                 return;
+            }
 
-            xform.ActivelyLerping = true;
-            _lerpingTransforms.Add(xform);
-        }
+            xform.LastLerp = _gameTiming.CurTick;
+            if (!_gameTiming.IsFirstTimePredicted)
+            {
+                xform.ActivelyLerping = false;
+                return;
+            }
 
-        public override void DeactivateLerp(TransformComponent component)
-        {
-            // this should cause the lerp to do nothing
-            component.NextPosition = null;
-            component.NextRotation = null;
-            component.LerpParent = EntityUid.Invalid;
+            if (!xform.ActivelyLerping)
+            {
+                _lerpingTransforms.Add(xform);
+                xform.ActivelyLerping = true;
+                xform.PredictedLerp = true;
+                xform.PrevRotation = xform._localRotation;
+                xform.PrevPosition = xform._localPosition;
+                xform.LerpParent = xform.ParentUid;
+                return;
+            }
+
+            if (!xform.PredictedLerp || xform.LerpParent != xform.ParentUid)
+            {
+                // Existing lerp was not due to prediction, but due to state application. That lerp should already
+                // have been rendered, so we will start a new lerp from the current position.
+                xform.PrevRotation = xform._localRotation;
+                xform.PrevPosition = xform._localPosition;
+                xform.LerpParent = xform.ParentUid;
+            }
         }
 
         public override void FrameUpdate(float frameTime)
@@ -74,11 +124,13 @@ namespace Robust.Client.GameObjects
             for (var i = 0; i < _lerpingTransforms.Count; i++)
             {
                 var transform = _lerpingTransforms[i];
+                var uid = transform.Owner;
                 var found = false;
 
                 // Only lerp if parent didn't change.
                 // E.g. entering lockers would do it.
-                if (transform.LerpParent == transform.ParentUid
+                if (transform.ActivelyLerping
+                    && transform.LerpParent == transform.ParentUid
                     && transform.ParentUid.IsValid()
                     && !transform.Deleted)
                 {
@@ -90,8 +142,7 @@ namespace Robust.Client.GameObjects
 
                         if (distance is > MinInterpolationDistanceSquared and < MaxInterpolationDistanceSquared)
                         {
-                            transform.LocalPosition = Vector2.Lerp(lerpSource, lerpDest, step);
-                            // Setting LocalPosition clears LerpPosition so fix that.
+                            SetLocalPositionNoLerp(uid, Vector2.Lerp(lerpSource, lerpDest, step), transform);
                             transform.NextPosition = lerpDest;
                             found = true;
                         }
@@ -101,15 +152,9 @@ namespace Robust.Client.GameObjects
                     {
                         var lerpDest = transform.NextRotation.Value;
                         var lerpSource = transform.PrevRotation;
-                        var distance = Math.Abs(Angle.ShortestDistance(lerpDest, lerpSource));
-
-                        if (distance is > MinInterpolationAngle and < MaxInterpolationAngle)
-                        {
-                            transform.LocalRotation = Angle.Lerp(lerpSource, lerpDest, step);
-                            // Setting LocalRotation clears LerpAngle so fix that.
-                            transform.NextRotation = lerpDest;
-                            found = true;
-                        }
+                        SetLocalRotationNoLerp(uid, Angle.Lerp(lerpSource, lerpDest, step), transform);
+                        transform.NextRotation = lerpDest;
+                        found = true;
                     }
                 }
 

Robust.Client/GameStates/ClientGameStateManager.cs

@@ -111,6 +111,13 @@ namespace Robust.Client.GameStates
 
         public event Action<MsgStateLeavePvs>? PvsLeave;
 
+#if DEBUG
+        /// <summary>
+        /// If true, this will cause received game states to be ignored. Used by integration tests.
+        /// </summary>
+        public bool DropStates;
+#endif
+
         /// <inheritdoc />
         public void Initialize()
         {
@@ -203,6 +210,10 @@ namespace Robust.Client.GameStates
 
         private void HandleStateMessage(MsgState message)
         {
+#if DEBUG
+            if (DropStates)
+                return;
+#endif
             // We ONLY ack states that are definitely going to get applied. Otherwise the sever might assume that we
             // applied a state containing entity-creation information, which it would then no longer send to us when
             // we re-encounter this entity
@@ -277,18 +288,15 @@ namespace Robust.Client.GameStates
                     continue;
                 }
 
-                if (PredictionNeedsResetting)
+                try
                 {
-                    try
-                    {
-                        ResetPredictedEntities();
-                    }
-                    catch (Exception e)
-                    {
-                        // avoid exception spam from repeatedly trying to reset the same entity.
-                        _entitySystemManager.GetEntitySystem<ClientDirtySystem>().Reset();
-                        _runtimeLog.LogException(e, "ResetPredictedEntities");
-                    }
+                    ResetPredictedEntities();
+                }
+                catch (Exception e)
+                {
+                    // avoid exception spam from repeatedly trying to reset the same entity.
+                    _entitySystemManager.GetEntitySystem<ClientDirtySystem>().Reset();
+                    _runtimeLog.LogException(e, "ResetPredictedEntities");
                 }
 
                 // If we were waiting for a new state, we are now applying it.
@@ -477,20 +485,22 @@ namespace Robust.Client.GameStates
 
         public void ResetPredictedEntities()
         {
-            PredictionNeedsResetting = false;
-
             using var _ = _prof.Group("ResetPredictedEntities");
             using var __ = _timing.StartStateApplicationArea();
 
+            // This is terrible, and I hate it. This also needs to run even when prediction is disabled.
+            _entitySystemManager.GetEntitySystem<SharedGridTraversalSystem>().QueuedEvents.Clear();
+            _entitySystemManager.GetEntitySystem<TransformSystem>().Reset();
+
+            if (!PredictionNeedsResetting)
+                return;
+
+            PredictionNeedsResetting = false;
             var countReset = 0;
             var system = _entitySystemManager.GetEntitySystem<ClientDirtySystem>();
             var metaQuery = _entityManager.GetEntityQuery<MetaDataComponent>();
             RemQueue<Component> toRemove = new();
 
-            // This is terrible, and I hate it.
-            _entitySystemManager.GetEntitySystem<SharedGridTraversalSystem>().QueuedEvents.Clear();
-            _entitySystemManager.GetEntitySystem<TransformSystem>().Reset();
-
             foreach (var entity in system.DirtyEntities)
             {
                 DebugTools.Assert(toRemove.Count == 0);
@@ -1443,6 +1453,9 @@ namespace Robust.Client.GameStates
         }
         #endregion
 
+        public bool IsQueuedForDetach(NetEntity entity)
+            => _processor.IsQueuedForDetach(entity);
+
         void IPostInjectInit.PostInject()
         {
             _sawmill = _logMan.GetSawmill(CVars.NetPredict.Name);

Robust.Client/GameStates/GameStateProcessor.cs

@@ -404,6 +404,18 @@ namespace Robust.Client.GameStates
             return _lastStateFullRep.TryGetValue(entity, out dictionary);
         }
 
+        public bool IsQueuedForDetach(NetEntity entity)
+        {
+            // This isn't fast, but its just meant for use in tests & debug asserts.
+            foreach (var msg in _pvsDetachMessages.Values)
+            {
+                if (msg.Contains(entity))
+                    return true;
+            }
+
+            return false;
+        }
+
         public int CalculateBufferSize(GameTick fromTick)
         {
             bool foundState;

Robust.Client/GameStates/NetInterpOverlay.cs

@@ -1,19 +1,19 @@
+using System;
 using Robust.Shared.Enums;
 using Robust.Client.Graphics;
 using Robust.Shared.Console;
 using Robust.Shared.GameObjects;
 using Robust.Shared.IoC;
 using Robust.Shared.Maths;
-using Robust.Shared.Physics;
 using Robust.Shared.Prototypes;
 using Robust.Shared.Containers;
-using Robust.Shared.Physics.Components;
 using Robust.Shared.Timing;
 
 namespace Robust.Client.GameStates
 {
     internal sealed class NetInterpOverlay : Overlay
     {
+        [Dependency] private readonly IGameTiming _timing = default!;
         [Dependency] private readonly IEntityManager _entityManager = default!;
         [Dependency] private readonly IEyeManager _eyeManager = default!;
         [Dependency] private readonly IPrototypeManager _prototypeManager = default!;
@@ -24,6 +24,11 @@ namespace Robust.Client.GameStates
         private readonly SharedContainerSystem _container;
         private readonly SharedTransformSystem _xform;
 
+        /// <summary>
+        /// When an entity stops lerping the overlay will continue to draw a box around the entity for this amount of time.
+        /// </summary>
+        public static readonly TimeSpan Delay = TimeSpan.FromSeconds(2f);
+
         public NetInterpOverlay(EntityLookupSystem lookup)
         {
             IoCManager.InjectDependencies(this);
@@ -40,8 +45,8 @@ namespace Robust.Client.GameStates
             var worldHandle = (DrawingHandleWorld) handle;
             var viewport = args.WorldAABB;
 
-            var query = _entityManager.AllEntityQueryEnumerator<PhysicsComponent, TransformComponent>();
-            while (query.MoveNext(out var uid, out var physics, out var transform))
+            var query = _entityManager.AllEntityQueryEnumerator<TransformComponent>();
+            while (query.MoveNext(out var uid, out var transform))
             {
                 // if not on the same map, continue
                 if (transform.MapID != _eyeManager.CurrentMap || _container.IsEntityInContainer(uid))
@@ -50,8 +55,8 @@ namespace Robust.Client.GameStates
                 if (transform.GridUid == uid)
                     continue;
 
-                // This entity isn't lerping, no need to draw debug info for it
-                if(transform.NextPosition == null)
+                var delta = (_timing.CurTick.Value - transform.LastLerp.Value) * _timing.TickPeriod;
+                if(!transform.ActivelyLerping && delta > Delay)
                     continue;
 
                 var aabb = _lookup.GetWorldAABB(uid);
@@ -61,7 +66,9 @@ namespace Robust.Client.GameStates
                     continue;
 
                 var (pos, rot) = _xform.GetWorldPositionRotation(transform, _entityManager.GetEntityQuery<TransformComponent>());
-                var boxOffset = transform.NextPosition.Value - transform.LocalPosition;
+                var boxOffset = transform.NextPosition != null
+                    ? transform.NextPosition.Value - transform.LocalPosition
+                    : default;
                 var worldOffset = (rot - transform.LocalRotation).RotateVec(boxOffset);
 
                 var nextPos = pos + worldOffset;

Robust.Client/Physics/PhysicsSystem.cs

@@ -82,11 +82,8 @@ namespace Robust.Client.Physics
                     continue;
                 }
 
-                xform.PrevPosition = position;
-                xform.PrevRotation = rotation;
-                xform.LerpParent = parentUid;
-                xform.NextPosition = xform.LocalPosition;
-                xform.NextRotation = xform.LocalRotation;
+                // Transform system will handle lerping.
+                _transform.SetLocalPositionRotation(uid, xform.LocalPosition, xform.LocalRotation, xform);
             }
 
             component.LerpData.Clear();

Robust.Server/GameStates/PvsSystem.cs

@@ -188,6 +188,7 @@ internal sealed partial class PvsSystem : EntitySystem
         Log.Warning(sb.ToString());
 
         sessionData.LastSeenAt.Clear();
+        sessionData.LastLeftView.Clear();
 
         if (sessionData.Overflow != null)
         {
@@ -256,6 +257,7 @@ internal sealed partial class PvsSystem : EntitySystem
         foreach (var sessionData in PlayerData.Values)
         {
             sessionData.LastSeenAt.Remove(metadata.NetEntity);
+            sessionData.LastLeftView.Remove(metadata.NetEntity);
             if (sessionData.SentEntities.TryGetValue(previousTick, out var ents))
                 ents.Remove(metadata.NetEntity);
         }
@@ -703,6 +705,7 @@ internal sealed partial class PvsSystem : EntitySystem
         sessionData.SentEntities.TryGetValue(toTick - 1, out var lastSent);
         var lastAcked = sessionData.LastAcked?.Data;
         var lastSeen = sessionData.LastSeenAt;
+        var lastLeft = sessionData.LastLeftView;
         var visibleEnts = _visSetPool.Get();
 
         if (visibleEnts.Count != 0)
@@ -730,7 +733,7 @@ internal sealed partial class PvsSystem : EntitySystem
 
             foreach (var rootNode in cache.Value.tree.RootNodes)
             {
-                RecursivelyAddTreeNode(in rootNode, cache.Value.tree, lastAcked, lastSent, visibleEnts, lastSeen, cache.Value.metadata, stack, in fromTick,
+                RecursivelyAddTreeNode(in rootNode, cache.Value.tree, lastAcked, lastSent, visibleEnts, lastSeen, lastLeft, cache.Value.metadata, stack, in fromTick,
                         ref newEntityCount, ref enteredEntityCount, ref entStateCount,  in newEntityBudget, in enteredEntityBudget);
             }
         }
@@ -741,7 +744,7 @@ internal sealed partial class PvsSystem : EntitySystem
         {
             var netEntity = globalEnumerator.Current;
             var uid = GetEntity(netEntity);
-            RecursivelyAddOverride(in uid, lastAcked, lastSent, visibleEnts, lastSeen, in fromTick,
+            RecursivelyAddOverride(in uid, lastAcked, lastSent, visibleEnts, lastSeen, lastLeft, in fromTick,
                 ref newEntityCount, ref enteredEntityCount, ref entStateCount, in newEntityBudget, in enteredEntityBudget);
         }
         globalEnumerator.Dispose();
@@ -751,7 +754,7 @@ internal sealed partial class PvsSystem : EntitySystem
         {
             var netEntity = globalRecursiveEnumerator.Current;
             var uid = GetEntity(netEntity);
-            RecursivelyAddOverride(in uid, lastAcked, lastSent, visibleEnts, lastSeen, in fromTick,
+            RecursivelyAddOverride(in uid, lastAcked, lastSent, visibleEnts, lastSeen, lastLeft, in fromTick,
                 ref newEntityCount, ref enteredEntityCount, ref entStateCount, in newEntityBudget, in enteredEntityBudget, true);
         }
         globalRecursiveEnumerator.Dispose();
@@ -761,14 +764,14 @@ internal sealed partial class PvsSystem : EntitySystem
         {
             var netEntity = sessionOverrides.Current;
             var uid = GetEntity(netEntity);
-            RecursivelyAddOverride(in uid, lastAcked, lastSent, visibleEnts, lastSeen,in fromTick,
+            RecursivelyAddOverride(in uid, lastAcked, lastSent, visibleEnts, lastSeen, lastLeft, in fromTick,
                 ref newEntityCount, ref enteredEntityCount, ref entStateCount, in newEntityBudget, in enteredEntityBudget, true);
         }
         sessionOverrides.Dispose();
 
         foreach (var viewerEntity in viewers)
         {
-            RecursivelyAddOverride(in viewerEntity, lastAcked, lastSent, visibleEnts, lastSeen, in fromTick,
+            RecursivelyAddOverride(in viewerEntity, lastAcked, lastSent, visibleEnts, lastSeen, lastLeft, in fromTick,
                 ref newEntityCount, ref enteredEntityCount, ref entStateCount, in newEntityBudget, in enteredEntityBudget);
         }
 
@@ -778,7 +781,7 @@ internal sealed partial class PvsSystem : EntitySystem
         {
             foreach (var entityUid in expandEvent.Entities)
             {
-                RecursivelyAddOverride(in entityUid, lastAcked, lastSent, visibleEnts, lastSeen, in fromTick,
+                RecursivelyAddOverride(in entityUid, lastAcked, lastSent, visibleEnts, lastSeen, lastLeft, in fromTick,
                     ref newEntityCount, ref enteredEntityCount, ref entStateCount, in newEntityBudget, in enteredEntityBudget);
             }
         }
@@ -787,7 +790,7 @@ internal sealed partial class PvsSystem : EntitySystem
         {
             foreach (var entityUid in expandEvent.RecursiveEntities)
             {
-                RecursivelyAddOverride(in entityUid, lastAcked, lastSent, visibleEnts, lastSeen,in fromTick,
+                RecursivelyAddOverride(in entityUid, lastAcked, lastSent, visibleEnts, lastSeen, lastLeft, in fromTick,
                     ref newEntityCount, ref enteredEntityCount, ref entStateCount, in newEntityBudget, in enteredEntityBudget, true);
             }
         }
@@ -826,7 +829,7 @@ internal sealed partial class PvsSystem : EntitySystem
         }
 
         // tell a client to detach entities that have left their view
-        var leftView = ProcessLeavePVS(visibleEnts, lastSent);
+        var leftView = ProcessLeavePvs(visibleEnts, lastSent, lastLeft);
 
         if (sessionData.SentEntities.Add(toTick, visibleEnts, out var oldEntry))
         {
@@ -863,18 +866,26 @@ internal sealed partial class PvsSystem : EntitySystem
     ///     Figure out what entities are no longer visible to the client. These entities are sent reliably to the client
     ///     in a separate net message.
     /// </summary>
-    private List<NetEntity>? ProcessLeavePVS(
+    private List<NetEntity>? ProcessLeavePvs(
         Dictionary<NetEntity, PvsEntityVisibility> visibleEnts,
-        Dictionary<NetEntity, PvsEntityVisibility>? lastSent)
+        Dictionary<NetEntity, PvsEntityVisibility>? lastSent,
+        Dictionary<NetEntity, GameTick> lastLeft)
     {
         if (lastSent == null)
             return null;
 
-        var leftView = new List<NetEntity>();
+        var tick = _gameTiming.CurTick;
+        var minSize = Math.Max(0, lastSent.Count - lastSent.Count);
+        var leftView = new List<NetEntity>(minSize);
+
         foreach (var netEntity in lastSent.Keys)
         {
             if (!visibleEnts.ContainsKey(netEntity))
+            {
                 leftView.Add(netEntity);
+                lastLeft[netEntity] = tick;
+            }
+
         }
 
         return leftView.Count > 0 ? leftView : null;
@@ -886,6 +897,7 @@ internal sealed partial class PvsSystem : EntitySystem
         Dictionary<NetEntity, PvsEntityVisibility>? lastSent,
         Dictionary<NetEntity, PvsEntityVisibility> toSend,
         Dictionary<NetEntity, GameTick> lastSeen,
+        Dictionary<NetEntity, GameTick> lastLeft,
         Dictionary<NetEntity, MetaDataComponent> metaDataCache,
         Stack<NetEntity> stack,
         in GameTick fromTick,
@@ -908,7 +920,7 @@ internal sealed partial class PvsSystem : EntitySystem
             ref var value = ref CollectionsMarshal.GetValueRefOrAddDefault(toSend, currentNodeIndex, out var exists);
             if (!exists)
             {
-                var (entered, shouldAdd) = ProcessEntry(in currentNodeIndex, lastAcked, lastSent, lastSeen,
+                var (entered, shouldAdd) = ProcessEntry(in currentNodeIndex, lastAcked, lastSent, lastSeen, lastLeft, fromTick,
                     ref newEntityCount, ref enteredEntityCount, newEntityBudget, enteredEntityBudget);
 
                 if (!shouldAdd)
@@ -938,6 +950,7 @@ internal sealed partial class PvsSystem : EntitySystem
         Dictionary<NetEntity, PvsEntityVisibility>? lastSent,
         Dictionary<NetEntity, PvsEntityVisibility> toSend,
         Dictionary<NetEntity, GameTick> lastSeen,
+        Dictionary<NetEntity, GameTick> lastLeft,
         in GameTick fromTick,
         ref int newEntityCount,
         ref int enteredEntityCount,
@@ -953,7 +966,7 @@ internal sealed partial class PvsSystem : EntitySystem
 
         var xform = _xformQuery.GetComponent(uid);
         var parent = xform.ParentUid;
-        if (parent.IsValid() && !RecursivelyAddOverride(in parent, lastAcked, lastSent, toSend, lastSeen, in fromTick,
+        if (parent.IsValid() && !RecursivelyAddOverride(in parent, lastAcked, lastSent, toSend, lastSeen, lastLeft, in fromTick,
                 ref newEntityCount, ref enteredEntityCount, ref entStateCount, in newEntityBudget,
                 in enteredEntityBudget))
         {
@@ -963,7 +976,6 @@ internal sealed partial class PvsSystem : EntitySystem
         var metadata = _metaQuery.GetComponent(uid);
         var netEntity = metadata.NetEntity;
 
-        //did we already get added?
         // Note that we check this AFTER adding parents. This is because while this entity may already have been added
         // to the toSend set, it doesn't guarantee that its parents have been. E.g., if a player ghost just teleported
         // to follow a far away entity, the player's own entity is still being sent, but we need to ensure that we also
@@ -971,17 +983,13 @@ internal sealed partial class PvsSystem : EntitySystem
         ref var value = ref CollectionsMarshal.GetValueRefOrAddDefault(toSend, netEntity, out var exists);
         if (!exists)
         {
-            // TODO PERFORMANCE.
-            // ProcessEntry() unnecessarily checks lastSent.ContainsKey() and maybe lastSeen.Contains(). Given that at this
-            // point the budgets are just ignored, this should just bypass those checks. But then again 99% of the time this
-            // is just the player's own entity + maybe a singularity. So currently not all that performance intensive.
-            var (entered, _) = ProcessEntry(in netEntity, lastAcked, lastSent, lastSeen, ref newEntityCount, ref enteredEntityCount, newEntityBudget, enteredEntityBudget);
+            var (entered, _) = ProcessEntry(in netEntity, lastAcked, lastSent, lastSeen, lastLeft, fromTick, ref newEntityCount, ref enteredEntityCount, newEntityBudget, enteredEntityBudget);
             AddToSendSet(in netEntity, metadata, ref value, toSend, fromTick, in entered, ref entStateCount);
         }
 
         if (addChildren)
         {
-            RecursivelyAddChildren(xform, lastAcked, lastSent, toSend, lastSeen, fromTick, ref newEntityCount,
+            RecursivelyAddChildren(xform, lastAcked, lastSent, toSend, lastSeen, lastLeft, fromTick, ref newEntityCount,
                 ref enteredEntityCount, ref entStateCount, in newEntityBudget, in enteredEntityBudget);
         }
 
@@ -993,6 +1001,7 @@ internal sealed partial class PvsSystem : EntitySystem
         Dictionary<NetEntity, PvsEntityVisibility>? lastSent,
         Dictionary<NetEntity, PvsEntityVisibility> toSend,
         Dictionary<NetEntity, GameTick> lastSeen,
+        Dictionary<NetEntity, GameTick> lastLeft,
         in GameTick fromTick,
         ref int newEntityCount,
         ref int enteredEntityCount,
@@ -1011,22 +1020,23 @@ internal sealed partial class PvsSystem : EntitySystem
             ref var value = ref CollectionsMarshal.GetValueRefOrAddDefault(toSend, childNetEntity, out var exists);
             if (!exists)
             {
-                var (entered, _) = ProcessEntry(in childNetEntity, lastAcked, lastSent, lastSeen, ref newEntityCount,
+                var (entered, _) = ProcessEntry(in childNetEntity, lastAcked, lastSent, lastSeen, lastLeft, fromTick, ref newEntityCount,
                     ref enteredEntityCount, newEntityBudget, enteredEntityBudget);
 
                 AddToSendSet(in childNetEntity, metadata, ref value, toSend, fromTick, in entered, ref entStateCount);
             }
 
-            RecursivelyAddChildren(childXform, lastAcked, lastSent, toSend, lastSeen, fromTick, ref newEntityCount,
+            RecursivelyAddChildren(childXform, lastAcked, lastSent, toSend, lastSeen, lastLeft, fromTick, ref newEntityCount,
                 ref enteredEntityCount, ref entStateCount, in newEntityBudget, in enteredEntityBudget);
         }
     }
 
-    private (bool Entered, bool ShouldAdd) ProcessEntry(
-        in NetEntity netEntity,
+    private (bool Entered, bool ShouldAdd) ProcessEntry(in NetEntity netEntity,
         Dictionary<NetEntity, PvsEntityVisibility>? lastAcked,
         Dictionary<NetEntity, PvsEntityVisibility>? lastSent,
         Dictionary<NetEntity, GameTick> lastSeen,
+        Dictionary<NetEntity, GameTick> lastLeft,
+        GameTick fromTick,
         ref int newEntityCount,
         ref int enteredEntityCount,
         in int newEntityBudget,
@@ -1034,16 +1044,15 @@ internal sealed partial class PvsSystem : EntitySystem
     {
         var enteredSinceLastSent = lastSent == null || !lastSent.ContainsKey(netEntity);
 
-        var entered = enteredSinceLastSent || // OR, entered since last ack:
-                        lastAcked == null || !lastAcked.ContainsKey(netEntity);
+        var entered = enteredSinceLastSent
+                      || lastAcked == null
+                      || !lastAcked.ContainsKey(netEntity) // entered since last acked
+                      || lastLeft.GetValueOrDefault(netEntity) >= fromTick; // Just in case a packet was lost. I love dictionary lookups
 
         // If the entity is entering, but we already sent this entering entity in the last message, we won't add it to
         // the budget. Chances are the packet will arrive in a nice and orderly fashion, and the client will stick to
         // their requested budget. However this can cause issues if a packet gets dropped, because a player may create
         // 2x or more times the normal entity creation budget.
-        //
-        // The fix for that would be to just also give the PVS budget a client-side aspect that controls entity creation
-        // rate.
         if (enteredSinceLastSent)
         {
             if (newEntityCount >= newEntityBudget || enteredEntityCount >= enteredEntityBudget)
@@ -1374,6 +1383,11 @@ Transform last modified: {Transform(uid).LastModifiedTick}");
         /// </summary>
         public readonly Dictionary<NetEntity, GameTick> LastSeenAt = new();
 
+        /// <summary>
+        ///     Tick at which an entity last left a player's PVS view.
+        /// </summary>
+        public readonly Dictionary<NetEntity, GameTick> LastLeftView = new();
+
         /// <summary>
         ///     <see cref="SentEntities"/> overflow in case a player's last ack is more than <see cref="DirtyBufferSize"/> ticks behind the current tick.
         /// </summary>

Robust.Shared/Containers/ContainerHelpers.cs

@@ -1,191 +0,0 @@
-using System;
-using System.Diagnostics.CodeAnalysis;
-using JetBrains.Annotations;
-using Robust.Shared.GameObjects;
-using Robust.Shared.IoC;
-using Robust.Shared.Map;
-using Robust.Shared.Utility;
-
-namespace Robust.Shared.Containers
-{
-    /// <summary>
-    /// Helper functions for the container system.
-    /// </summary>
-    [PublicAPI]
-    public static class ContainerHelpers
-    {
-        /// <summary>
-        /// Am I inside a container? Only checks the direct parent. To see if the entity, or any parent entity, is
-        /// inside a container, use <see cref="ContainerSystem.IsEntityOrParentInContainer"/>
-        /// </summary>
-        /// <param name="entity">Entity that might be inside a container.</param>
-        /// <returns>If the entity is inside of a container.</returns>
-        [Obsolete("Use ContainerSystem.IsEntityInContainer() instead")]
-        public static bool IsInContainer(this EntityUid entity,
-            IEntityManager? entMan = null)
-        {
-            IoCManager.Resolve(ref entMan);
-            return (entMan.GetComponent<MetaDataComponent>(entity).Flags & MetaDataFlags.InContainer) == MetaDataFlags.InContainer;
-        }
-
-        /// <summary>
-        /// Tries to find the container manager that this entity is inside (if any).
-        /// </summary>
-        /// <param name="entity">Entity that might be inside a container.</param>
-        /// <param name="manager">The container manager that this entity is inside of.</param>
-        /// <returns>If a container manager was found.</returns>
-        public static bool TryGetContainerMan(this EntityUid entity, [NotNullWhen(true)] out ContainerManagerComponent? manager, IEntityManager? entMan = null)
-        {
-            IoCManager.Resolve(ref entMan);
-            DebugTools.Assert(entMan.EntityExists(entity));
-
-            var parent = entMan.GetComponent<TransformComponent>(entity).ParentUid;
-            if (parent.IsValid() && TryGetManagerComp(parent, out manager, entMan) && manager.ContainsEntity(entity))
-                return true;
-
-            manager = default;
-            return false;
-        }
-
-        /// <summary>
-        /// Tries to find the container that this entity is inside (if any).
-        /// </summary>
-        /// <param name="entity">Entity that might be inside a container.</param>
-        /// <param name="container">The container that this entity is inside of.</param>
-        /// <returns>If a container was found.</returns>
-        [Obsolete("Use ContainerSystem.TryGetContainingContainer() instead")]
-        public static bool TryGetContainer(this EntityUid entity, [NotNullWhen(true)] out BaseContainer? container, IEntityManager? entMan = null)
-        {
-            IoCManager.Resolve(ref entMan);
-            DebugTools.Assert(entMan.EntityExists(entity));
-
-            if (TryGetContainerMan(entity, out var manager, entMan))
-                return manager.TryGetContainer(entity, out container);
-
-            container = default;
-            return false;
-        }
-
-        /// <summary>
-        /// Attempts to remove an entity from its container, if any.
-        /// <see cref="SharedContainerSystem.TryRemoveFromContainer"/>
-        /// </summary>
-        /// <param name="entity">Entity that might be inside a container.</param>
-        /// <param name="force">Whether to forcibly remove the entity from the container.</param>
-        /// <param name="wasInContainer">Whether the entity was actually inside a container or not.</param>
-        /// <returns>If the entity could be removed. Also returns false if it wasn't inside a container.</returns>
-        [Obsolete("Use SharedContainerSystem.TryRemoveFromContainer() instead")]
-        public static bool TryRemoveFromContainer(this EntityUid entity, bool force, out bool wasInContainer, IEntityManager? entMan = null)
-        {
-            return IoCManager.Resolve<IEntitySystemManager>().GetEntitySystem<SharedContainerSystem>()
-                .TryRemoveFromContainer(entity, force, out wasInContainer);
-        }
-
-        /// <summary>
-        /// Attempts to remove an entity from its container, if any.
-        /// <see cref="SharedContainerSystem.TryRemoveFromContainer"/>
-        /// </summary>
-        /// <param name="entity">Entity that might be inside a container.</param>
-        /// <param name="force">Whether to forcibly remove the entity from the container.</param>
-        /// <returns>If the entity could be removed. Also returns false if it wasn't inside a container.</returns>
-        [Obsolete("Use SharedContainerSystem.TryRemoveFromContainer() instead")]
-        public static bool TryRemoveFromContainer(this EntityUid entity, bool force = false, IEntityManager? entMan = null)
-        {
-            return IoCManager.Resolve<IEntitySystemManager>().GetEntitySystem<SharedContainerSystem>()
-                .TryRemoveFromContainer(entity, force);
-        }
-
-        /// <summary>
-        /// Attempts to remove all entities in a container.
-        /// <see cref="SharedContainerSystem.EmptyContainer"/>
-        /// </summary>
-        [Obsolete("Use SharedContainerSystem.EmptyContainer() instead")]
-        public static void EmptyContainer(this BaseContainer container, bool force = false, EntityCoordinates? moveTo = null,
-            bool attachToGridOrMap = false, IEntityManager? entMan = null)
-        {
-            IoCManager.Resolve<IEntitySystemManager>().GetEntitySystem<SharedContainerSystem>()
-                .EmptyContainer(container, force, moveTo, attachToGridOrMap);
-        }
-
-        /// <summary>
-        /// Attempts to remove and delete all entities in a container.
-        /// <see cref="SharedContainerSystem.CleanContainer"/>
-        /// </summary>
-        [Obsolete("Use SharedContainerSystem.CleanContainer() instead")]
-        public static void CleanContainer(this BaseContainer container, IEntityManager? entMan = null)
-        {
-            IoCManager.Resolve<IEntitySystemManager>().GetEntitySystem<SharedContainerSystem>()
-                .CleanContainer(container);
-        }
-
-        /// <summary>
-        /// <see cref="SharedContainerSystem.AttachParentToContainerOrGrid"/>
-        /// </summary>
-        [Obsolete("Use SharedContainerSystem.AttachParentToContainerOrGrid() instead")]
-        public static void AttachParentToContainerOrGrid(this TransformComponent transform, IEntityManager? entMan = null)
-        {
-            IoCManager.Resolve<IEntitySystemManager>().GetEntitySystem<SharedContainerSystem>()
-                .AttachParentToContainerOrGrid(transform);
-        }
-
-        /// <summary>
-        /// <see cref="SharedContainerSystem.TryGetManagerComp"/>
-        /// </summary>
-        [Obsolete("Use SharedContainerSystem.TryGetManagerComp() instead")]
-        private static bool TryGetManagerComp(this EntityUid entity, [NotNullWhen(true)] out ContainerManagerComponent? manager, IEntityManager? entMan = null)
-        {
-            IoCManager.Resolve(ref entMan);
-            return entMan.System<SharedContainerSystem>()
-                .TryGetManagerComp(entity, out manager);
-        }
-
-        /// <summary>
-        /// Shortcut method to make creation of containers easier.
-        /// Creates a new container on the entity and gives it back to you.
-        /// </summary>
-        /// <param name="entity">The entity to create the container for.</param>
-        /// <param name="containerId"></param>
-        /// <returns>The new container.</returns>
-        /// <exception cref="ArgumentException">Thrown if there already is a container with the specified ID.</exception>
-        /// <seealso cref="BaseContainerManager.MakeContainer{T}(string)" />
-        [Obsolete("Use ContainerSystem.MakeContainer() instead")]
-        public static T CreateContainer<T>(this EntityUid entity, string containerId, IEntityManager? entMan = null)
-            where T : BaseContainer
-        {
-            IoCManager.Resolve(ref entMan);
-            var containermanager = entMan.EnsureComponent<ContainerManagerComponent>(entity);
-            return containermanager.MakeContainer<T>(containerId);
-        }
-
-        [Obsolete("Use ContainerSystem.EnsureContainer() instead")]
-        public static T EnsureContainer<T>(this EntityUid entity, string containerId, IEntityManager? entMan = null)
-            where T : BaseContainer
-        {
-            IoCManager.Resolve(ref entMan);
-            return EnsureContainer<T>(entity, containerId, out _, entMan);
-        }
-
-        [Obsolete("Use ContainerSystem.EnsureContainer() instead")]
-        public static T EnsureContainer<T>(this EntityUid entity, string containerId, out bool alreadyExisted, IEntityManager? entMan = null)
-            where T : BaseContainer
-        {
-            IoCManager.Resolve(ref entMan);
-            var containerManager = entMan.EnsureComponent<ContainerManagerComponent>(entity);
-
-            if (!containerManager.TryGetContainer(containerId, out var existing))
-            {
-                alreadyExisted = false;
-                return containerManager.MakeContainer<T>(containerId);
-            }
-
-            if (!(existing is T container))
-            {
-                throw new InvalidOperationException(
-                    $"The container exists but is of a different type: {existing.GetType()}");
-            }
-
-            alreadyExisted = true;
-            return container;
-        }
-    }
-}

Robust.Shared/GameObjects/ComponentExt.cs

@@ -1,75 +0,0 @@
-using System;
-using System.Collections.Generic;
-using JetBrains.Annotations;
-using Robust.Shared.IoC;
-using Robust.Shared.Log;
-
-namespace Robust.Shared.GameObjects
-{
-    [PublicAPI]
-    public static class ComponentExt
-    {
-        /// <summary>
-        ///     Convenience wrapper to implement "create component if it does not already exist".
-        ///     Always gives you back a component, and creates it if it does not exist yet.
-        /// </summary>
-        /// <param name="entity">The entity to fetch or create the component on.</param>
-        /// <typeparam name="T">The type of the component to fetch or create.</typeparam>
-        /// <returns>The existing component, or the new component if none existed yet.</returns>
-        [Obsolete]
-        public static T EnsureComponent<T>(this EntityUid entity) where T : Component, new()
-        {
-            var entMan = IoCManager.Resolve<IEntityManager>();
-            if (entMan.TryGetComponent(entity, out T? component))
-            {
-                return component;
-            }
-
-            return entMan.AddComponent<T>(entity);
-        }
-
-        /// <summary>
-        ///     Convenience wrapper to implement "create component if it does not already exist".
-        ///     Always gives you back a component, and creates it if it does not exist yet.
-        /// </summary>
-        /// <param name="entity">The entity to fetch or create the component on.</param>
-        /// <typeparam name="T">The type of the component to fetch or create.</typeparam>
-        /// <param name="warning">
-        ///     The custom warning message to log if the component did not exist already.
-        ///     Defaults to a predetermined warning if null.
-        /// </param>
-        /// <returns>The existing component, or the new component if none existed yet.</returns>
-        [Obsolete]
-        public static T EnsureComponentWarn<T>(this EntityUid entity, string? warning = null) where T : Component, new()
-        {
-            var entMan = IoCManager.Resolve<IEntityManager>();
-            if (entMan.TryGetComponent(entity, out T? component))
-            {
-                return component;
-            }
-
-            warning ??= $"Entity {entity} at {entMan.GetComponent<TransformComponent>(entity).MapPosition} did not have a {typeof(T)}";
-
-            Logger.Warning(warning);
-
-            return entMan.AddComponent<T>(entity);
-        }
-
-        [Obsolete]
-        public static IComponent SetAndDirtyIfChanged<TValue>(
-            this IComponent comp,
-            ref TValue backingField,
-            TValue value)
-        {
-            if (EqualityComparer<TValue>.Default.Equals(backingField, value))
-            {
-                return comp;
-            }
-
-            backingField = value;
-            comp.Dirty();
-
-            return comp;
-        }
-    }
-}

Robust.Shared/GameObjects/Components/Transform/TransformComponent.cs

@@ -85,8 +85,9 @@ namespace Robust.Shared.GameObjects
         [ViewVariables]
         public Angle PrevRotation { get; internal set; }
 
-        [ViewVariables(VVAccess.ReadWrite)]
-        internal bool ActivelyLerping { get; set; }
+        [ViewVariables] public bool ActivelyLerping;
+
+        [ViewVariables] public GameTick LastLerp = GameTick.Zero;
 
         [ViewVariables] internal readonly HashSet<EntityUid> _children = new();
 
@@ -397,7 +398,8 @@ namespace Robust.Shared.GameObjects
 
         [ViewVariables] public int ChildCount => _children.Count;
 
-        [ViewVariables] internal EntityUid LerpParent { get; set; }
+        [ViewVariables] public EntityUid LerpParent;
+        public bool PredictedLerp;
 
         /// <summary>
         /// Detaches this entity from its parent.

Robust.Shared/GameObjects/EntityManager.cs

@@ -398,6 +398,7 @@ namespace Robust.Shared.GameObjects
             if (component.LifeStage >= ComponentLifeStage.Removing || !component.NetSyncEnabled)
                 return;
 
+            DebugTools.AssertOwner(uid, component);
             DirtyEntity(uid, meta);
             component.LastModifiedTick = CurrentTick;
         }

Robust.Shared/GameObjects/Systems/SharedTransformSystem.Component.cs

@@ -149,7 +149,7 @@ public abstract partial class SharedTransformSystem
     /// </summary>
     public bool ContainsEntity(TransformComponent xform, EntityUid entity)
     {
-        return ContainsEntity(xform, entity, _xformQuery);
+        return ContainsEntity(xform, entity, XformQuery);
     }
 
     /// <inheritdoc cref="ContainsEntity(Robust.Shared.GameObjects.TransformComponent,Robust.Shared.GameObjects.EntityUid)"/>
@@ -161,7 +161,7 @@ public abstract partial class SharedTransformSystem
     /// <inheritdoc cref="ContainsEntity(Robust.Shared.GameObjects.TransformComponent,Robust.Shared.GameObjects.EntityUid)"/>
     public bool ContainsEntity(TransformComponent xform, TransformComponent entityTransform)
     {
-        return ContainsEntity(xform, entityTransform, _xformQuery);
+        return ContainsEntity(xform, entityTransform, XformQuery);
     }
 
     /// <inheritdoc cref="ContainsEntity(Robust.Shared.GameObjects.TransformComponent,Robust.Shared.GameObjects.EntityUid)"/>
@@ -222,7 +222,7 @@ public abstract partial class SharedTransformSystem
 
         if (!component._mapIdInitialized)
         {
-            FindMapIdAndSet(uid, component, EntityManager, _xformQuery, _mapManager);
+            FindMapIdAndSet(uid, component, EntityManager, XformQuery, _mapManager);
             component._mapIdInitialized = true;
         }
 
@@ -232,7 +232,7 @@ public abstract partial class SharedTransformSystem
             // Note that _children is a HashSet<EntityUid>,
             // so duplicate additions (which will happen) don't matter.
 
-            var parentXform = _xformQuery.GetComponent(component.ParentUid);
+            var parentXform = XformQuery.GetComponent(component.ParentUid);
             if (parentXform.LifeStage > ComponentLifeStage.Running || LifeStage(component.ParentUid) > EntityLifeStage.MapInitialized)
             {
                 var msg = $"Attempted to re-parent to a terminating object. Entity: {ToPrettyString(component.ParentUid)}, new parent: {ToPrettyString(uid)}";
@@ -298,7 +298,7 @@ public abstract partial class SharedTransformSystem
         if (!xform._parent.IsValid())
             return;
 
-        var parentXform = _xformQuery.GetComponent(xform._parent);
+        var parentXform = XformQuery.GetComponent(xform._parent);
         InitializeGridUid(xform._parent, parentXform);
         xform._gridUid = parentXform._gridUid;
     }
@@ -356,7 +356,7 @@ public abstract partial class SharedTransformSystem
         DebugTools.Assert(!HasComp<MapGridComponent>(uid));
         DebugTools.Assert(gridId == null || HasComp<MapGridComponent>(gridId));
 
-        xformQuery ??= _xformQuery;
+        xformQuery ??= XformQuery;
         SetGridIdRecursive(uid, xform, gridId, xformQuery.Value);
     }
 
@@ -379,27 +379,26 @@ public abstract partial class SharedTransformSystem
 
     #region Local Position
 
-    public void SetLocalPosition(EntityUid uid, Vector2 value, TransformComponent? xform = null)
+    [Obsolete("use override with EntityUid")]
+    public void SetLocalPosition(TransformComponent xform, Vector2 value)
     {
-        if (!Resolve(uid, ref xform)) return;
-        SetLocalPosition(xform, value);
+        SetLocalPosition(xform.Owner, value, xform);
     }
 
-    public virtual void SetLocalPosition(TransformComponent xform, Vector2 value)
-    {
-#pragma warning disable CS0618
-        xform.LocalPosition = value;
-#pragma warning restore CS0618
-    }
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public virtual void SetLocalPosition(EntityUid uid, Vector2 value, TransformComponent? xform = null)
+        => SetLocalPositionNoLerp(uid, value, xform);
+
+
+    [Obsolete("use override with EntityUid")]
+    public void SetLocalPositionNoLerp(TransformComponent xform, Vector2 value)
+        => SetLocalPositionNoLerp(xform.Owner, value, xform);
 
     public void SetLocalPositionNoLerp(EntityUid uid, Vector2 value, TransformComponent? xform = null)
     {
-        if (!Resolve(uid, ref xform)) return;
-        SetLocalPositionNoLerp(xform, value);
-    }
+        if (!XformQuery.Resolve(uid, ref xform))
+            return;
 
-    public virtual void SetLocalPositionNoLerp(TransformComponent xform, Vector2 value)
-    {
 #pragma warning disable CS0618
         xform.LocalPosition = value;
 #pragma warning restore CS0618
@@ -409,27 +408,24 @@ public abstract partial class SharedTransformSystem
 
     #region Local Rotation
 
-    public void SetLocalRotationNoLerp(EntityUid uid, Angle angle)
+    public void SetLocalRotationNoLerp(EntityUid uid, Angle value, TransformComponent? xform = null)
     {
-        SetLocalRotationNoLerp(_xformQuery.GetComponent(uid), angle);
-    }
+        if (!XformQuery.Resolve(uid, ref xform))
+            return;
 
-    public virtual void SetLocalRotationNoLerp(TransformComponent xform, Angle angle)
-    {
-        xform.LocalRotation = angle;
-    }
-
-    public void SetLocalRotation(EntityUid uid, Angle value, TransformComponent? xform = null)
-    {
-        if (!Resolve(uid, ref xform)) return;
-        SetLocalRotation(xform, value);
-    }
-
-    public virtual void SetLocalRotation(TransformComponent xform, Angle value)
-    {
         xform.LocalRotation = value;
     }
 
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public virtual void SetLocalRotation(EntityUid uid, Angle value, TransformComponent? xform = null)
+        => SetLocalRotationNoLerp(uid, value, xform);
+
+    [Obsolete("use override with EntityUid")]
+    public void SetLocalRotation(TransformComponent xform, Angle value)
+    {
+        SetLocalRotation(xform.Owner, value, xform);
+    }
+
     #endregion
 
     #region Coordinates
@@ -487,7 +483,7 @@ public abstract partial class SharedTransformSystem
 
             if (value.EntityId.IsValid())
             {
-                if (!_xformQuery.Resolve(value.EntityId, ref newParent, false))
+                if (!XformQuery.Resolve(value.EntityId, ref newParent, false))
                 {
                     DetachParentToNull(uid, xform);
                     if (_netMan.IsServer || IsClientSide(uid))
@@ -525,13 +521,13 @@ public abstract partial class SharedTransformSystem
                         }
 
                         recursiveUid = recursiveXform.ParentUid;
-                        recursiveXform = _xformQuery.GetComponent(recursiveUid);
+                        recursiveXform = XformQuery.GetComponent(recursiveUid);
                     }
                 }
             }
 
             if (xform._parent.IsValid())
-                _xformQuery.Resolve(xform._parent, ref oldParent);
+                XformQuery.Resolve(xform._parent, ref oldParent);
 
             oldParent?._children.Remove(uid);
             newParent?._children.Add(uid);
@@ -541,7 +537,7 @@ public abstract partial class SharedTransformSystem
 
             if (newParent != null)
             {
-                xform.ChangeMapId(newParent.MapID, _xformQuery);
+                xform.ChangeMapId(newParent.MapID, XformQuery);
 
                 if (!xform._gridInitialized)
                     InitializeGridUid(uid, xform);
@@ -554,11 +550,11 @@ public abstract partial class SharedTransformSystem
             }
             else
             {
-                xform.ChangeMapId(MapId.Nullspace, _xformQuery);
+                xform.ChangeMapId(MapId.Nullspace, XformQuery);
                 if (!xform._gridInitialized)
                     InitializeGridUid(uid, xform);
                 else
-                    SetGridId(uid, xform, null, _xformQuery);
+                    SetGridId(uid, xform, null, XformQuery);
             }
 
             if (xform.Initialized)
@@ -593,7 +589,7 @@ public abstract partial class SharedTransformSystem
 
     public void ReparentChildren(EntityUid oldUid, EntityUid uid)
     {
-        ReparentChildren(oldUid, uid, _xformQuery);
+        ReparentChildren(oldUid, uid, XformQuery);
     }
 
     /// <summary>
@@ -620,29 +616,29 @@ public abstract partial class SharedTransformSystem
 
     public TransformComponent? GetParent(EntityUid uid)
     {
-        return GetParent(_xformQuery.GetComponent(uid));
+        return GetParent(XformQuery.GetComponent(uid));
     }
 
     public TransformComponent? GetParent(TransformComponent xform)
     {
         if (!xform.ParentUid.IsValid())
             return null;
-        return _xformQuery.GetComponent(xform.ParentUid);
+        return XformQuery.GetComponent(xform.ParentUid);
     }
 
     public EntityUid GetParentUid(EntityUid uid)
     {
-        return _xformQuery.GetComponent(uid).ParentUid;
+        return XformQuery.GetComponent(uid).ParentUid;
     }
 
     public void SetParent(EntityUid uid, EntityUid parent)
     {
-        SetParent(uid, _xformQuery.GetComponent(uid), parent, _xformQuery);
+        SetParent(uid, XformQuery.GetComponent(uid), parent, XformQuery);
     }
 
     public void SetParent(EntityUid uid, TransformComponent xform, EntityUid parent, TransformComponent? parentXform = null)
     {
-        SetParent(uid, xform, parent, _xformQuery, parentXform);
+        SetParent(uid, xform, parent, XformQuery, parentXform);
     }
 
     public void SetParent(EntityUid uid, TransformComponent xform, EntityUid parent, EntityQuery<TransformComponent> xformQuery, TransformComponent? parentXform = null)
@@ -671,9 +667,7 @@ public abstract partial class SharedTransformSystem
     #endregion
 
     #region States
-    public virtual void ActivateLerp(TransformComponent xform) { }
-
-    public virtual void DeactivateLerp(TransformComponent xform) { }
+    public virtual void ActivateLerp(EntityUid uid, TransformComponent xform) { }
 
     internal void OnGetState(EntityUid uid, TransformComponent component, ref ComponentGetState args)
     {
@@ -745,24 +739,18 @@ public abstract partial class SharedTransformSystem
                 RaiseLocalEvent(uid, ref ev, true);
             }
 
-            xform.PrevPosition = newState.LocalPosition;
-            xform.PrevRotation = newState.Rotation;
             xform._noLocalRotation = newState.NoLocalRotation;
 
             DebugTools.Assert(xform.ParentUid == parent, "Transform state failed to set parent");
             DebugTools.Assert(xform.Anchored == newState.Anchored, "Transform state failed to set anchored");
         }
 
-        if (args.Next is TransformComponentState nextTransform)
+        if (args.Next is TransformComponentState nextTransform
+            && nextTransform.ParentID == GetNetEntity(xform.ParentUid))
         {
             xform.NextPosition = nextTransform.LocalPosition;
             xform.NextRotation = nextTransform.Rotation;
-            xform.LerpParent = GetEntity(nextTransform.ParentID);
-            ActivateLerp(xform);
-        }
-        else
-        {
-            DeactivateLerp(xform);
+            ActivateLerp(uid, xform);
         }
     }
 
@@ -773,7 +761,7 @@ public abstract partial class SharedTransformSystem
     [Pure]
     public Matrix3 GetWorldMatrix(EntityUid uid)
     {
-        return GetWorldMatrix(_xformQuery.GetComponent(uid), _xformQuery);
+        return GetWorldMatrix(XformQuery.GetComponent(uid), XformQuery);
     }
 
     // Temporary until it's moved here
@@ -781,7 +769,7 @@ public abstract partial class SharedTransformSystem
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public Matrix3 GetWorldMatrix(TransformComponent component)
     {
-        return GetWorldMatrix(component, _xformQuery);
+        return GetWorldMatrix(component, XformQuery);
     }
 
     [Pure]
@@ -807,7 +795,7 @@ public abstract partial class SharedTransformSystem
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public Vector2 GetWorldPosition(EntityUid uid)
     {
-        return GetWorldPosition(_xformQuery.GetComponent(uid));
+        return GetWorldPosition(XformQuery.GetComponent(uid));
     }
 
     // Temporary until it's moved here
@@ -819,7 +807,7 @@ public abstract partial class SharedTransformSystem
 
         while (component.ParentUid != component.MapUid && component.ParentUid.IsValid())
         {
-            component = _xformQuery.GetComponent(component.ParentUid);
+            component = XformQuery.GetComponent(component.ParentUid);
             pos = component._localRotation.RotateVec(pos) + component._localPosition;
         }
 
@@ -842,7 +830,7 @@ public abstract partial class SharedTransformSystem
     [Pure]
     public (Vector2 WorldPosition, Angle WorldRotation) GetWorldPositionRotation(EntityUid uid)
     {
-        return GetWorldPositionRotation(_xformQuery.GetComponent(uid));
+        return GetWorldPositionRotation(XformQuery.GetComponent(uid));
     }
 
     [Pure]
@@ -853,7 +841,7 @@ public abstract partial class SharedTransformSystem
 
         while (component.ParentUid != component.MapUid && component.ParentUid.IsValid())
         {
-            component = _xformQuery.GetComponent(component.ParentUid);
+            component = XformQuery.GetComponent(component.ParentUid);
             pos = component._localRotation.RotateVec(pos) + component._localPosition;
             angle += component._localRotation;
         }
@@ -947,7 +935,7 @@ public abstract partial class SharedTransformSystem
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public void SetWorldPosition(TransformComponent component, Vector2 worldPos)
     {
-        SetWorldPosition(component, worldPos, _xformQuery);
+        SetWorldPosition(component, worldPos, XformQuery);
     }
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
@@ -973,7 +961,7 @@ public abstract partial class SharedTransformSystem
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public Angle GetWorldRotation(EntityUid uid)
     {
-        return GetWorldRotation(_xformQuery.GetComponent(uid), _xformQuery);
+        return GetWorldRotation(XformQuery.GetComponent(uid), XformQuery);
     }
 
     // Temporary until it's moved here
@@ -981,7 +969,7 @@ public abstract partial class SharedTransformSystem
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public Angle GetWorldRotation(TransformComponent component)
     {
-        return GetWorldRotation(component, _xformQuery);
+        return GetWorldRotation(component, XformQuery);
     }
 
     [Pure]
@@ -1040,43 +1028,47 @@ public abstract partial class SharedTransformSystem
     #region Set Position+Rotation
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    public void SetWorldPositionRotation(EntityUid uid, Vector2 worldPos, Angle worldRot, EntityQuery<TransformComponent> xformQuery)
-    {
-        var component = xformQuery.GetComponent(uid);
-        SetWorldPositionRotation(component, worldPos, worldRot, xformQuery);
-    }
-
-    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    [Obsolete("Use override with EntityUid")]
     public void SetWorldPositionRotation(TransformComponent component, Vector2 worldPos, Angle worldRot)
     {
-        SetWorldPositionRotation(component, worldPos, worldRot, _xformQuery);
+        SetWorldPositionRotation(component.Owner, worldPos, worldRot, component);
     }
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    public void SetWorldPositionRotation(TransformComponent component, Vector2 worldPos, Angle worldRot, EntityQuery<TransformComponent> xformQuery)
+    public void SetWorldPositionRotation(EntityUid uid, Vector2 worldPos, Angle worldRot, TransformComponent? component = null)
     {
+        if (!XformQuery.Resolve(uid, ref component))
+            return;
+
         if (!component._parent.IsValid())
         {
             DebugTools.Assert("Parent is invalid while attempting to set WorldPosition - did you try to move root node?");
             return;
         }
 
-        var (curWorldPos, curWorldRot) = GetWorldPositionRotation(component, xformQuery);
+        var (curWorldPos, curWorldRot) = GetWorldPositionRotation(component);
 
         var negativeParentWorldRot = component.LocalRotation - curWorldRot;
 
         var newLocalPos = component.LocalPosition + negativeParentWorldRot.RotateVec(worldPos - curWorldPos);
         var newLocalRot = component.LocalRotation + worldRot - curWorldRot;
 
-        SetLocalPositionRotation(component, newLocalPos, newLocalRot);
+        SetLocalPositionRotation(uid, newLocalPos, newLocalRot, component);
     }
 
+    [Obsolete("Use override with EntityUid")]
+    public void SetLocalPositionRotation(TransformComponent xform, Vector2 pos, Angle rot)
+        => SetLocalPositionRotation(xform.Owner, pos, rot, xform);
+
     /// <summary>
     ///     Simultaneously set the position and rotation. This is better than setting individually, as it reduces the number of move events and matrix rebuilding operations.
     /// </summary>
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    public virtual void SetLocalPositionRotation(TransformComponent xform, Vector2 pos, Angle rot)
+    public virtual void SetLocalPositionRotation(EntityUid uid, Vector2 pos, Angle rot, TransformComponent? xform = null)
     {
+        if (!XformQuery.Resolve(uid, ref xform))
+            return;
+
         if (!xform._parent.IsValid())
         {
             DebugTools.Assert("Parent is invalid while attempting to set WorldPosition - did you try to move root node?");
@@ -1097,14 +1089,14 @@ public abstract partial class SharedTransformSystem
 
         DebugTools.Assert(!xform.NoLocalRotation || xform.LocalRotation == 0);
 
-        Dirty(xform.Owner, xform);
+        Dirty(uid, xform);
         xform.MatricesDirty = true;
 
         if (!xform.Initialized)
             return;
 
-        var moveEvent = new MoveEvent(xform.Owner, oldPosition, xform.Coordinates, oldRotation, rot, xform, _gameTiming.ApplyingState);
-        RaiseLocalEvent(xform.Owner, ref moveEvent, true);
+        var moveEvent = new MoveEvent(uid, oldPosition, xform.Coordinates, oldRotation, rot, xform, _gameTiming.ApplyingState);
+        RaiseLocalEvent(uid, ref moveEvent, true);
     }
 
     #endregion
@@ -1114,14 +1106,14 @@ public abstract partial class SharedTransformSystem
     [Pure]
     public Matrix3 GetInvWorldMatrix(EntityUid uid)
     {
-        return GetInvWorldMatrix(_xformQuery.GetComponent(uid), _xformQuery);
+        return GetInvWorldMatrix(XformQuery.GetComponent(uid), XformQuery);
     }
 
     [Pure]
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public Matrix3 GetInvWorldMatrix(TransformComponent component)
     {
-        return GetInvWorldMatrix(component, _xformQuery);
+        return GetInvWorldMatrix(component, XformQuery);
     }
 
     [Pure]
@@ -1146,14 +1138,14 @@ public abstract partial class SharedTransformSystem
     public (Vector2 WorldPosition, Angle WorldRotation, Matrix3 WorldMatrix)
         GetWorldPositionRotationMatrix(EntityUid uid)
     {
-        return GetWorldPositionRotationMatrix(_xformQuery.GetComponent(uid), _xformQuery);
+        return GetWorldPositionRotationMatrix(XformQuery.GetComponent(uid), XformQuery);
     }
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public (Vector2 WorldPosition, Angle WorldRotation, Matrix3 WorldMatrix)
         GetWorldPositionRotationMatrix(TransformComponent xform)
     {
-        return GetWorldPositionRotationMatrix(xform, _xformQuery);
+        return GetWorldPositionRotationMatrix(xform, XformQuery);
     }
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
@@ -1177,13 +1169,13 @@ public abstract partial class SharedTransformSystem
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public (Vector2 WorldPosition, Angle WorldRotation, Matrix3 InvWorldMatrix) GetWorldPositionRotationInvMatrix(EntityUid uid)
     {
-        return GetWorldPositionRotationInvMatrix(_xformQuery.GetComponent(uid));
+        return GetWorldPositionRotationInvMatrix(XformQuery.GetComponent(uid));
     }
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public (Vector2 WorldPosition, Angle WorldRotation, Matrix3 InvWorldMatrix) GetWorldPositionRotationInvMatrix(TransformComponent xform)
     {
-        return GetWorldPositionRotationInvMatrix(xform, _xformQuery);
+        return GetWorldPositionRotationInvMatrix(xform, XformQuery);
     }
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
@@ -1207,14 +1199,14 @@ public abstract partial class SharedTransformSystem
     public (Vector2 WorldPosition, Angle WorldRotation, Matrix3 WorldMatrix, Matrix3 InvWorldMatrix)
         GetWorldPositionRotationMatrixWithInv(EntityUid uid)
     {
-        return GetWorldPositionRotationMatrixWithInv(_xformQuery.GetComponent(uid), _xformQuery);
+        return GetWorldPositionRotationMatrixWithInv(XformQuery.GetComponent(uid), XformQuery);
     }
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public (Vector2 WorldPosition, Angle WorldRotation, Matrix3 WorldMatrix, Matrix3 InvWorldMatrix)
         GetWorldPositionRotationMatrixWithInv(TransformComponent xform)
     {
-        return GetWorldPositionRotationMatrixWithInv(xform, _xformQuery);
+        return GetWorldPositionRotationMatrixWithInv(xform, XformQuery);
     }
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
@@ -1237,8 +1229,8 @@ public abstract partial class SharedTransformSystem
     #region AttachToGridOrMap
     public void AttachToGridOrMap(EntityUid uid, TransformComponent? xform = null)
     {
-        if (_xformQuery.Resolve(uid, ref xform))
-            AttachToGridOrMap(uid, xform, _xformQuery);
+        if (XformQuery.Resolve(uid, ref xform))
+            AttachToGridOrMap(uid, xform, XformQuery);
     }
 
     public void AttachToGridOrMap(EntityUid uid, TransformComponent xform, EntityQuery<TransformComponent> query)
@@ -1278,15 +1270,15 @@ public abstract partial class SharedTransformSystem
     {
         coordinates = null;
 
-        if (!_xformQuery.Resolve(uid, ref xform))
+        if (!XformQuery.Resolve(uid, ref xform))
             return false;
 
         if (!xform.ParentUid.IsValid())
             return false;
 
         EntityUid newParent;
-        var oldPos = GetWorldPosition(xform, _xformQuery);
-        if (_mapManager.TryFindGridAt(xform.MapID, oldPos, _xformQuery, out var gridUid, out _))
+        var oldPos = GetWorldPosition(xform, XformQuery);
+        if (_mapManager.TryFindGridAt(xform.MapID, oldPos, XformQuery, out var gridUid, out _))
         {
             newParent = gridUid;
         }
@@ -1299,7 +1291,7 @@ public abstract partial class SharedTransformSystem
             return false;
         }
 
-        coordinates = new(newParent, GetInvWorldMatrix(newParent, _xformQuery).Transform(oldPos));
+        coordinates = new(newParent, GetInvWorldMatrix(newParent, XformQuery).Transform(oldPos));
         return true;
     }
     #endregion
@@ -1308,7 +1300,7 @@ public abstract partial class SharedTransformSystem
 
     public void DetachParentToNull(EntityUid uid, TransformComponent xform)
     {
-        _xformQuery.TryGetComponent(xform.ParentUid, out var oldXform);
+        XformQuery.TryGetComponent(xform.ParentUid, out var oldXform);
         DetachParentToNull(uid, xform, oldXform);
     }
 
@@ -1369,7 +1361,7 @@ public abstract partial class SharedTransformSystem
     {
         if (LifeStage(uid) > EntityLifeStage.Initialized)
         {
-            SetGridId(uid, component, uid, _xformQuery);
+            SetGridId(uid, component, uid, XformQuery);
             return;
         }
         component._gridInitialized = true;
@@ -1383,10 +1375,10 @@ public abstract partial class SharedTransformSystem
     public void PlaceNextToOrDrop(EntityUid uid, EntityUid target,
         TransformComponent? xform = null, TransformComponent? targetXform = null)
     {
-        if (!_xformQuery.Resolve(target, ref targetXform))
+        if (!XformQuery.Resolve(target, ref targetXform))
             return;
 
-        if (!_xformQuery.Resolve(uid, ref xform))
+        if (!XformQuery.Resolve(uid, ref xform))
             return;
 
         var meta = _metaQuery.GetComponent(target);

Robust.Shared/GameObjects/Systems/SharedTransformSystem.cs

@@ -26,7 +26,7 @@ namespace Robust.Shared.GameObjects
 
         private EntityQuery<MapGridComponent> _gridQuery;
         private EntityQuery<MetaDataComponent> _metaQuery;
-        private EntityQuery<TransformComponent> _xformQuery;
+        protected EntityQuery<TransformComponent> XformQuery;
 
         private readonly Queue<MoveEvent> _gridMoves = new();
         private readonly Queue<MoveEvent> _otherMoves = new();
@@ -39,7 +39,7 @@ namespace Robust.Shared.GameObjects
 
             _gridQuery = GetEntityQuery<MapGridComponent>();
             _metaQuery = GetEntityQuery<MetaDataComponent>();
-            _xformQuery = GetEntityQuery<TransformComponent>();
+            XformQuery = GetEntityQuery<TransformComponent>();
 
             SubscribeLocalEvent<TileChangedEvent>(MapManagerOnTileChanged);
             SubscribeLocalEvent<TransformComponent, ComponentInit>(OnCompInit);
@@ -85,17 +85,17 @@ namespace Robust.Shared.GameObjects
             if (!TryComp(gridId, out BroadphaseComponent? lookup) || !_mapManager.TryGetGrid(gridId, out var grid))
                 return;
 
-            if (!_xformQuery.TryGetComponent(gridId, out var gridXform))
+            if (!XformQuery.TryGetComponent(gridId, out var gridXform))
                 return;
 
-            if (!_xformQuery.TryGetComponent(gridXform.MapUid, out var mapTransform))
+            if (!XformQuery.TryGetComponent(gridXform.MapUid, out var mapTransform))
                 return;
 
             var aabb = _lookup.GetLocalBounds(tileIndices, grid.TileSize);
 
             foreach (var entity in _lookup.GetEntitiesIntersecting(lookup, aabb, LookupFlags.Uncontained | LookupFlags.Approximate))
             {
-                if (!_xformQuery.TryGetComponent(entity, out var xform) || xform.ParentUid != gridId)
+                if (!XformQuery.TryGetComponent(entity, out var xform) || xform.ParentUid != gridId)
                     continue;
 
                 if (!aabb.Contains(xform.LocalPosition))
@@ -148,7 +148,7 @@ namespace Robust.Shared.GameObjects
 
         public EntityCoordinates GetMoverCoordinates(EntityUid uid)
         {
-            return GetMoverCoordinates(uid, _xformQuery.GetComponent(uid));
+            return GetMoverCoordinates(uid, XformQuery.GetComponent(uid));
         }
 
         public EntityCoordinates GetMoverCoordinates(EntityUid uid, TransformComponent xform)
@@ -168,11 +168,11 @@ namespace Robust.Shared.GameObjects
             DebugTools.Assert(!_mapManager.IsGrid(uid) && !_mapManager.IsMap(uid));
 
             // Not parented to grid so convert their pos back to the grid.
-            var worldPos = GetWorldPosition(xform, _xformQuery);
+            var worldPos = GetWorldPosition(xform, XformQuery);
 
             return xform.GridUid == null
                 ? new EntityCoordinates(xform.MapUid ?? xform.ParentUid, worldPos)
-                : new EntityCoordinates(xform.GridUid.Value, _xformQuery.GetComponent(xform.GridUid.Value).InvLocalMatrix.Transform(worldPos));
+                : new EntityCoordinates(xform.GridUid.Value, XformQuery.GetComponent(xform.GridUid.Value).InvLocalMatrix.Transform(worldPos));
         }
 
         public EntityCoordinates GetMoverCoordinates(EntityCoordinates coordinates, EntityQuery<TransformComponent> xformQuery)
@@ -191,7 +191,7 @@ namespace Robust.Shared.GameObjects
             if (!parentUid.IsValid())
                 return coordinates;
 
-            var parentXform = _xformQuery.GetComponent(parentUid);
+            var parentXform = XformQuery.GetComponent(parentUid);
 
             // GriddUid is only set after init.
             if (!parentXform._gridInitialized)
@@ -209,11 +209,11 @@ namespace Robust.Shared.GameObjects
             DebugTools.Assert(!_mapManager.IsGrid(parentUid) && !_mapManager.IsMap(parentUid));
 
             // Not parented to grid so convert their pos back to the grid.
-            var worldPos = GetWorldMatrix(parentXform, _xformQuery).Transform(coordinates.Position);
+            var worldPos = GetWorldMatrix(parentXform, XformQuery).Transform(coordinates.Position);
 
             return parentXform.GridUid == null
                 ? new EntityCoordinates(mapId ?? parentUid, worldPos)
-                : new EntityCoordinates(parentXform.GridUid.Value, _xformQuery.GetComponent(parentXform.GridUid.Value).InvLocalMatrix.Transform(worldPos));
+                : new EntityCoordinates(parentXform.GridUid.Value, XformQuery.GetComponent(parentXform.GridUid.Value).InvLocalMatrix.Transform(worldPos));
         }
 
         /// <summary>
@@ -231,15 +231,15 @@ namespace Robust.Shared.GameObjects
 
             // Is the entity directly parented to the grid?
             if (xform.GridUid == xform.ParentUid)
-                return (xform.Coordinates, GetWorldRotation(xform, _xformQuery));
+                return (xform.Coordinates, GetWorldRotation(xform, XformQuery));
 
             DebugTools.Assert(!_mapManager.IsGrid(uid) && !_mapManager.IsMap(uid));
 
-            var (pos, worldRot) = GetWorldPositionRotation(xform, _xformQuery);
+            var (pos, worldRot) = GetWorldPositionRotation(xform, XformQuery);
 
             var coords = xform.GridUid == null
                 ? new EntityCoordinates(xform.MapUid ?? xform.ParentUid, pos)
-                : new EntityCoordinates(xform.GridUid.Value, _xformQuery.GetComponent(xform.GridUid.Value).InvLocalMatrix.Transform(pos));
+                : new EntityCoordinates(xform.GridUid.Value, XformQuery.GetComponent(xform.GridUid.Value).InvLocalMatrix.Transform(pos));
 
             return (coords, worldRot);
         }

Robust.Shared/Physics/Systems/SharedJointSystem.Relay.cs

@@ -3,7 +3,6 @@ using System.Collections.Generic;
 using Robust.Shared.GameObjects;
 using Robust.Shared.GameStates;
 using Robust.Shared.Physics.Components;
-using Robust.Shared.Physics.Dynamics.Joints;
 using Robust.Shared.Serialization;
 using Robust.Shared.Utility;
 
@@ -110,5 +109,29 @@ public abstract partial class SharedJointSystem
         }
 
         Dirty(uid, component);
+
+#if DEBUG
+        if (component.Relay == null)
+            return;
+
+        if (TryComp(uid, out JointComponent? jointComp))
+        {
+            foreach (var joint in jointComp.Joints.Values)
+            {
+                DebugTools.AssertNotEqual(joint.BodyAUid, component.Relay);
+                DebugTools.AssertNotEqual(joint.BodyBUid, component.Relay);
+
+            }
+        }
+
+        if (TryComp(component.Relay, out JointComponent? relayJointComp))
+        {
+            foreach (var joint in relayJointComp.Joints.Values)
+            {
+                DebugTools.AssertNotEqual(joint.BodyAUid, uid);
+                DebugTools.AssertNotEqual(joint.BodyBUid, uid);
+            }
+        }
+#endif
     }
 }

Robust.Shared/Physics/Systems/SharedJointSystem.cs

@@ -140,6 +140,8 @@ public abstract partial class SharedJointSystem : EntitySystem
         jointComponentA ??= EnsureComp<JointComponent>(aUid);
         jointComponentB ??= EnsureComp<JointComponent>(bUid);
         DebugTools.Assert(jointComponentA.Owner == aUid && jointComponentB.Owner == bUid);
+        DebugTools.AssertNotEqual(jointComponentA.Relay, bUid);
+        DebugTools.AssertNotEqual(jointComponentB.Relay, aUid);
 
         var jointsA = jointComponentA.Joints;
         var jointsB = jointComponentB.Joints;
@@ -190,10 +192,10 @@ public abstract partial class SharedJointSystem : EntitySystem
 
         _physics.WakeBody(aUid, body: bodyA);
         _physics.WakeBody(bUid, body: bodyB);
-        Dirty(bodyA);
-        Dirty(bodyB);
-        Dirty(jointComponentA);
-        Dirty(jointComponentB);
+        Dirty(aUid, bodyA);
+        Dirty(bUid, bodyB);
+        Dirty(aUid, jointComponentA);
+        Dirty(bUid, jointComponentB);
 
         // Also flag these for checking juusssttt in case.
         _dirtyJoints.Add(jointComponentA);

Robust.Shared/Physics/Systems/SharedPhysicsSystem.Island.cs

@@ -423,16 +423,19 @@ public abstract partial class SharedPhysicsSystem
 
                             var uidA = joint.BodyAUid;
                             var uidB = joint.BodyBUid;
+                            DebugTools.AssertNotEqual(uidA, uidB);
 
                             if (jointQuery.TryGetComponent(uidA, out var jointCompA) &&
                                 jointCompA.Relay != null)
                             {
+                                DebugTools.AssertNotEqual(uidB, jointCompA.Relay.Value);
                                 uidA = jointCompA.Relay.Value;
                             }
 
                             if (jointQuery.TryGetComponent(uidB, out var jointCompB) &&
                                 jointCompB.Relay != null)
                             {
+                                DebugTools.AssertNotEqual(uidA, jointCompB.Relay.Value);
                                 uidB = jointCompB.Relay.Value;
                             }
 

Robust.UnitTesting/Server/GameObjects/Components/Container_Test.cs

@@ -222,9 +222,9 @@ namespace Robust.UnitTesting.Server.GameObjects.Components
             Assert.That(entManager.GetComponent<TransformComponent>(containerEntity).ChildCount, Is.EqualTo(1));
             Assert.That(entManager.GetComponent<TransformComponent>(containerEntity).ChildEntities.First(), Is.EqualTo(insertEntity));
 
-            result = insertEntity.TryGetContainerMan(out var resultContainerMan);
+            result = containerSys.TryGetContainingContainer(insertEntity, out var resultContainerMan);
             Assert.That(result, Is.True);
-            Assert.That(resultContainerMan, Is.EqualTo(container.Manager));
+            Assert.That(resultContainerMan?.Manager, Is.EqualTo(container.Manager));
         }
 
         [Test]

Robust.UnitTesting/Server/GameStates/PvsReEntryTest.cs

@@ -0,0 +1,214 @@
+using System.Linq;
+using System.Numerics;
+using System.Threading.Tasks;
+using NUnit.Framework;
+using Robust.Client.GameStates;
+using Robust.Client.Timing;
+using Robust.Server.GameObjects;
+using Robust.Server.Player;
+using Robust.Shared;
+using Robust.Shared.Configuration;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Map;
+using Robust.Shared.Network;
+using Robust.Shared.Timing;
+using cIPlayerManager = Robust.Client.Player.IPlayerManager;
+using sIPlayerManager = Robust.Server.Player.IPlayerManager;
+
+namespace Robust.UnitTesting.Server.GameStates;
+
+public sealed class PvsReEntryTest : RobustIntegrationTest
+{
+#if DEBUG
+    /// <summary>
+    /// Checks that there are no issues when an entity enters, leaves, then enters pvs while the client drops packets.
+    /// </summary>
+    [Test]
+    public async Task TestLossyReEntry()
+    {
+        var server = StartServer();
+        var client = StartClient();
+
+        await Task.WhenAll(client.WaitIdleAsync(), server.WaitIdleAsync());
+
+        var mapMan = server.ResolveDependency<IMapManager>();
+        var sEntMan = server.ResolveDependency<IEntityManager>();
+        var confMan = server.ResolveDependency<IConfigurationManager>();
+        var sPlayerMan = server.ResolveDependency<sIPlayerManager>();
+        var xforms = sEntMan.System<SharedTransformSystem>();
+        var stateMan = (ClientGameStateManager) client.ResolveDependency<IClientGameStateManager>();
+
+        var cEntMan = client.ResolveDependency<IEntityManager>();
+        var netMan = client.ResolveDependency<IClientNetManager>();
+        var cPlayerMan = client.ResolveDependency<cIPlayerManager>();
+
+        Assert.DoesNotThrow(() => client.SetConnectTarget(server));
+        client.Post(() => netMan.ClientConnect(null!, 0, null!));
+        server.Post(() => confMan.SetCVar(CVars.NetPVS, true));
+
+        for (int i = 0; i < 10; i++)
+        {
+            await server.WaitRunTicks(1);
+            await client.WaitRunTicks(1);
+        }
+
+        // Ensure client & server ticks are synced.
+        // Client runs 1 tick ahead
+        {
+            var sTick = (int)server.Timing.CurTick.Value;
+            var cTick = (int)client.Timing.CurTick.Value;
+            var delta = cTick - sTick;
+
+            if (delta > 1)
+                await server.WaitRunTicks(delta - 1);
+            else if (delta < 1)
+                await client.WaitRunTicks(1 - delta);
+
+            sTick = (int)server.Timing.CurTick.Value;
+            cTick = (int)client.Timing.CurTick.Value;
+            delta = cTick - sTick;
+            Assert.That(delta, Is.EqualTo(1));
+        }
+
+        // Set up map and spawn player
+        EntityUid map = default;
+        NetEntity player = default;
+        NetEntity entity = default;
+        EntityCoordinates coords = default;
+        await server.WaitPost(() =>
+        {
+            var mapId = mapMan.CreateMap();
+            map = mapMan.GetMapEntityId(mapId);
+            coords = new(map, default);
+
+            var playerUid = sEntMan.SpawnEntity(null, coords);
+            var entUid = sEntMan.SpawnEntity(null, coords);
+            entity = sEntMan.GetNetEntity(entUid);
+            player = sEntMan.GetNetEntity(playerUid);
+
+            // Attach player.
+            var session = (IPlayerSession) sPlayerMan.Sessions.First();
+            sEntMan.System<ActorSystem>().Attach(playerUid, session);
+            session.JoinGame();
+        });
+
+        for (int i = 0; i < 10; i++)
+        {
+            await server.WaitRunTicks(1);
+            await client.WaitRunTicks(1);
+        }
+
+        Assert.That(player, Is.Not.EqualTo(NetEntity.Invalid));
+        Assert.That(entity, Is.Not.EqualTo(NetEntity.Invalid));
+
+        // Check player got properly attached, and has received the other entity.
+        MetaDataComponent? meta = default!;
+        await client.WaitPost(() =>
+        {
+            Assert.That(cEntMan.TryGetEntityData(entity, out _, out meta));
+            Assert.That(cEntMan.TryGetEntity(player, out var cPlayerUid));
+            Assert.That(cPlayerMan.LocalPlayer?.ControlledEntity, Is.EqualTo(cPlayerUid));
+            Assert.That(meta!.Flags & MetaDataFlags.Detached, Is.EqualTo(MetaDataFlags.None));
+            Assert.That(stateMan.IsQueuedForDetach(entity), Is.False);
+        });
+
+        var lastDirty = meta.LastModifiedTick;
+        Assert.That(lastDirty, Is.GreaterThan(GameTick.Zero));
+
+        // Move the player outside of the entity's PVS range
+        // note that we move the PLAYER not the entity, as we don't want to dirty the entity.
+        var farAway = new EntityCoordinates(map, new Vector2(100, 100));
+        await server.WaitPost( () => xforms.SetCoordinates(sEntMan.GetEntity(player), farAway));
+        for (int i = 0; i < 10; i++)
+        {
+            await server.WaitRunTicks(1);
+            await client.WaitRunTicks(1);
+        }
+
+        // Client should have detached the entity to null space.
+        Assert.That(meta!.Flags & MetaDataFlags.Detached, Is.EqualTo(MetaDataFlags.Detached));
+        Assert.That(stateMan.IsQueuedForDetach(entity), Is.False);
+
+        // Move the player back into range
+        await server.WaitPost( () => xforms.SetCoordinates(sEntMan.GetEntity(player), coords));
+        for (int i = 0; i < 10; i++)
+        {
+            await server.WaitRunTicks(1);
+            await client.WaitRunTicks(1);
+        }
+
+        // Entity is back in pvs range
+        Assert.That(meta!.Flags & MetaDataFlags.Detached, Is.EqualTo(MetaDataFlags.None));
+        Assert.That(stateMan.IsQueuedForDetach(entity), Is.False);
+
+        // Oh no, the client is going through a tunnel!
+        stateMan.DropStates = true;
+        var timing = client.ResolveDependency<IClientGameTiming>();
+        var lastRealTick = timing.LastRealTick;
+
+        for (int i = 0; i < 5; i++)
+        {
+            await server.WaitRunTicks(1);
+            await client.WaitRunTicks(1);
+        }
+
+        // Even though the client is receiving no new states, it will still have applied some from the state buffer.
+        Assert.That(timing.LastRealTick, Is.GreaterThan(lastRealTick));
+        lastRealTick = timing.LastRealTick;
+
+        // Move the player outside of pvs range.
+        Assert.That(meta!.Flags & MetaDataFlags.Detached, Is.EqualTo(MetaDataFlags.None));
+        await server.WaitPost(() => xforms.SetCoordinates(sEntMan.GetEntity(player), farAway));
+
+        for (int i = 0; i < 5; i++)
+        {
+            await server.WaitRunTicks(1);
+            await client.WaitRunTicks(1);
+        }
+
+        // Client should have exhausted the buffer -- client has not been applying any states.
+        Assert.That(timing.LastRealTick, Is.EqualTo(lastRealTick));
+        Assert.That(meta!.Flags & MetaDataFlags.Detached, Is.EqualTo(MetaDataFlags.None));
+
+        // However pvs-leave messages are sent separately, and are sent reliably. So they are still being received.
+        // Though in a realistic scenario they should probably be delayed somewhat.
+        Assert.That(stateMan.IsQueuedForDetach(entity), Is.True);
+
+        // Move the entity back into range
+        await server.WaitPost( () => xforms.SetCoordinates(sEntMan.GetEntity(player), coords));
+
+        for (int i = 0; i < 5; i++)
+        {
+            await server.WaitRunTicks(1);
+            await client.WaitRunTicks(1);
+        }
+
+        // Still hasn't been applying states.
+        Assert.That(timing.LastRealTick, Is.EqualTo(lastRealTick));
+        Assert.That(meta!.Flags & MetaDataFlags.Detached, Is.EqualTo(MetaDataFlags.None));
+
+        // The pvs-leave message has not yet been processed, detaching is still queued.
+        Assert.That(stateMan.IsQueuedForDetach(entity), Is.True);
+
+        // Client clears the tunnel, starts receiving states again.
+        stateMan.DropStates = false;
+
+        for (int i = 0; i < 10; i++)
+        {
+            await server.WaitRunTicks(1);
+            await client.WaitRunTicks(1);
+        }
+
+        // Entity should be in PVS range, client should know about it:
+        Assert.That(timing.LastRealTick, Is.GreaterThan(lastRealTick));
+        Assert.That(meta!.Flags & MetaDataFlags.Detached, Is.EqualTo(MetaDataFlags.None));
+        Assert.That(stateMan.IsQueuedForDetach(entity), Is.False);
+
+        // The entity itself should not have been dirtied since creation -- only the player has been moving.
+        // If the test moves the entity instead of the player, then the test doesn't actually work.
+        Assert.That(meta.LastModifiedTick, Is.EqualTo(lastDirty));
+
+    }
+#endif
+}
+