Switched to byte-stream based transport

src/Avalonia.Base/Rendering/Composition/Animations/AnimatedValueStore.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Runtime.InteropServices;
 using Avalonia.Rendering.Composition.Expressions;
 using Avalonia.Rendering.Composition.Server;
@@ -81,7 +82,7 @@ namespace Avalonia.Rendering.Composition.Animations
 
         public bool IsAnimation => _animation != null;
 
-        public void SetAnimation(ServerObject target, ChangeSet cs, IAnimationInstance animation, int storeOffset)
+        public void SetAnimation(ServerObject target, TimeSpan commitedAt, IAnimationInstance animation, int storeOffset)
         {
             _direct = default;
             if (_animation != null)
@@ -91,7 +92,7 @@ namespace Avalonia.Rendering.Composition.Animations
             }
 
             _animation = animation;
-            _animation.Initialize(cs.Batch.CommitedAt, ExpressionVariant.Create(LastAnimated), storeOffset);
+            _animation.Initialize(commitedAt, ExpressionVariant.Create(LastAnimated), storeOffset);
             if (target.IsActive)
                 _animation.Activate();
             

src/Avalonia.Base/Rendering/Composition/Animations/CompositionAnimation.cs

@@ -18,8 +18,6 @@ namespace Avalonia.Rendering.Composition.Animations
               _propertySet = new CompositionPropertySet(compositor);
           }
 
-          private protected override IChangeSetPool ChangeSetPool => throw new InvalidOperationException();
-
           public void ClearAllParameters() => _propertySet.ClearAll();
 
           public void ClearParameter(string key) => _propertySet.Clear(key);
@@ -52,8 +50,7 @@ namespace Avalonia.Rendering.Composition.Animations
           internal abstract IAnimationInstance CreateInstance(ServerObject targetObject,
               ExpressionVariant? finalValue);
 
-          internal PropertySetSnapshot CreateSnapshot(bool server) 
-              => _propertySet.Snapshot(server);
+          internal PropertySetSnapshot CreateSnapshot() => _propertySet.Snapshot();
 
           void ICompositionAnimationBase.InternalOnly()
           {

src/Avalonia.Base/Rendering/Composition/Animations/CompositionAnimationGroup.cs

@@ -20,7 +20,5 @@ namespace Avalonia.Rendering.Composition.Animations
         public CompositionAnimationGroup(Compositor compositor) : base(compositor, null!)
         {
         }
-
-        private protected override IChangeSetPool ChangeSetPool => throw new InvalidOperationException();
     }
 }

src/Avalonia.Base/Rendering/Composition/Animations/ExpressionAnimation.cs

@@ -29,6 +29,6 @@ namespace Avalonia.Rendering.Composition.Animations
         internal override IAnimationInstance CreateInstance(
             ServerObject targetObject, ExpressionVariant? finalValue)
             => new ExpressionAnimationInstance(ParsedExpression,
-                targetObject, finalValue, CreateSnapshot(true));
+                targetObject, finalValue, CreateSnapshot());
     }
 }

src/Avalonia.Base/Rendering/Composition/Animations/ImplicitAnimationCollection.cs

@@ -15,8 +15,6 @@ namespace Avalonia.Rendering.Composition.Animations
             _innerface = _inner;
         }
 
-        private protected override IChangeSetPool ChangeSetPool => throw new InvalidOperationException();
-
         public IEnumerator<KeyValuePair<string, ICompositionAnimationBase>> GetEnumerator() => _inner.GetEnumerator();
 
         IEnumerator IEnumerable.GetEnumerator() => ((IEnumerable) _inner).GetEnumerator();

src/Avalonia.Base/Rendering/Composition/CompositionDrawListVisual.cs

@@ -9,7 +9,7 @@ internal class CompositionDrawListVisual : CompositionContainerVisual
 {
     public Visual Visual { get; }
 
-    private new DrawListVisualChanges Changes => (DrawListVisualChanges)base.Changes;
+    private bool _drawListChanged;
     private CompositionDrawList? _drawList;
     public CompositionDrawList? DrawList
     {
@@ -18,11 +18,21 @@ internal class CompositionDrawListVisual : CompositionContainerVisual
         {
             _drawList?.Dispose();
             _drawList = value;
-            Changes.DrawCommands = value?.Clone();
+            _drawListChanged = true;
+            RegisterForSerialization();
         }
     }
 
-    private protected override IChangeSetPool ChangeSetPool => DrawListVisualChanges.Pool;
+    private protected override void SerializeChangesCore(BatchStreamWriter writer)
+    {
+        writer.Write((byte)(_drawListChanged ? 1 : 0));
+        if (_drawListChanged)
+        {
+            writer.WriteObject(DrawList?.Clone());
+            _drawListChanged = false;
+        }
+        base.SerializeChangesCore(writer);
+    }
 
     internal CompositionDrawListVisual(Compositor compositor, ServerCompositionDrawListVisual server, Visual visual) : base(compositor, server)
     {

src/Avalonia.Base/Rendering/Composition/CompositionEasingFunction.cs

@@ -10,9 +10,7 @@ namespace Avalonia.Rendering.Composition
         internal CompositionEasingFunction(Compositor compositor) : base(compositor, null!)
         {
         }
-
-        private protected override IChangeSetPool ChangeSetPool => throw new InvalidOperationException();
-
+        
         internal abstract IEasingFunction Snapshot();
     }
     

src/Avalonia.Base/Rendering/Composition/CompositionObject.cs

@@ -6,7 +6,7 @@ using Avalonia.Rendering.Composition.Transport;
 
 namespace Avalonia.Rendering.Composition
 {
-    public abstract class CompositionObject : IDisposable, IExpressionObject
+    public abstract class CompositionObject : IDisposable
     {
         public ImplicitAnimationCollection? ImplicitAnimations { get; set; }
         internal CompositionObject(Compositor compositor, ServerObject server)
@@ -18,46 +18,17 @@ namespace Avalonia.Rendering.Composition
         public Compositor Compositor { get; }
         internal ServerObject Server { get; }
         public bool IsDisposed { get; private set; }
-        private ChangeSet? _changes;
+        private bool _registeredForSerialization;
 
         private static void ThrowInvalidOperation() =>
             throw new InvalidOperationException("There is no server-side counterpart for this object");
-        
-        private protected ChangeSet Changes
-        {
-            get
-            {
-                // ReSharper disable once ConditionIsAlwaysTrueOrFalse
-                if (Server == null) ThrowInvalidOperation();
-                var currentBatch = Compositor.CurrentBatch;
-                if (_changes != null && _changes.Batch != currentBatch)
-                    _changes = null;
-                if (_changes == null)
-                {
-                    _changes = ChangeSetPool.Get(Server!, currentBatch);
-                    currentBatch.Changes!.Add(_changes);
-                    Compositor.QueueImplicitBatchCommit();
-                }
-
-                return _changes;
-            }
-        }
-
-        private protected abstract IChangeSetPool ChangeSetPool { get; }
 
         public void Dispose()
         {
-            Changes.Dispose = true;
+            //Changes.Dispose = true;
             IsDisposed = true;
         }
 
-        internal virtual ExpressionVariant GetPropertyForAnimation(string name)
-        {
-            return default;
-        }
-
-        ExpressionVariant IExpressionObject.GetProperty(string name) => GetPropertyForAnimation(name);
-
         public void StartAnimation(string propertyName, CompositionAnimation animation)
             => StartAnimation(propertyName, animation, null);
         
@@ -121,5 +92,27 @@ namespace Avalonia.Rendering.Composition
 
             throw new ArgumentException();
         }
+
+        protected void RegisterForSerialization()
+        {
+            if (Server == null)
+                throw new InvalidOperationException("The object doesn't have an associated server counterpart");
+            
+            if(_registeredForSerialization)
+                return;
+            _registeredForSerialization = true;
+            Compositor.RegisterForSerialization(this);
+        }
+
+        internal void SerializeChanges(BatchStreamWriter writer)
+        {
+            _registeredForSerialization = false;
+            SerializeChangesCore(writer);
+        }
+
+        private protected virtual void SerializeChangesCore(BatchStreamWriter writer)
+        {
+            
+        }
     }
 }

src/Avalonia.Base/Rendering/Composition/CompositionPropertySet.cs

@@ -16,8 +16,6 @@ namespace Avalonia.Rendering.Composition
         {
         }
 
-        private protected override IChangeSetPool ChangeSetPool => throw new NotSupportedException();
-
         internal void Set(string key, ExpressionVariant value)
         {
             _objects.Remove(key);
@@ -104,10 +102,10 @@ namespace Avalonia.Rendering.Composition
             _variants.Remove(key);
         }
 
-        internal PropertySetSnapshot Snapshot(bool server) =>
-            SnapshotCore(server, 1);
+        internal PropertySetSnapshot Snapshot() =>
+            SnapshotCore(1);
         
-        private PropertySetSnapshot SnapshotCore(bool server, int allowedNestingLevel)
+        private PropertySetSnapshot SnapshotCore(int allowedNestingLevel)
         {
             var dic = new Dictionary<string, PropertySetSnapshot.Value>(_objects.Count + _variants.Count);
             foreach (var o in _objects)
@@ -116,12 +114,12 @@ namespace Avalonia.Rendering.Composition
                 {
                     if (allowedNestingLevel <= 0)
                         throw new InvalidOperationException("PropertySet depth limit reached");
-                    dic[o.Key] = new PropertySetSnapshot.Value(ps.SnapshotCore(server, allowedNestingLevel - 1));
+                    dic[o.Key] = new PropertySetSnapshot.Value(ps.SnapshotCore(allowedNestingLevel - 1));
                 }
                 else if (o.Value.Server == null)
                     throw new InvalidOperationException($"Object of type {o.Value.GetType()} is not allowed");
                 else
-                    dic[o.Key] = new PropertySetSnapshot.Value(server ? (IExpressionObject) o.Value.Server : o.Value);
+                    dic[o.Key] = new PropertySetSnapshot.Value(o.Value.Server);
             }
 
             foreach (var v in _variants)

src/Avalonia.Base/Rendering/Composition/CompositionTarget.cs

@@ -102,6 +102,6 @@ namespace Avalonia.Rendering.Composition
             return false;
         }
 
-        public void RequestRedraw() => Changes.RedrawRequested.Value = true;
+        public void RequestRedraw() => RegisterForSerialization();
     }
 }

src/Avalonia.Base/Rendering/Composition/Compositor.cs

@@ -16,18 +16,17 @@ namespace Avalonia.Rendering.Composition
     public partial class Compositor
     {
         private ServerCompositor _server;
-        private Batch _currentBatch;
         private bool _implicitBatchCommitQueued;
         private Action _implicitBatchCommit;
-
-        internal Batch CurrentBatch => _currentBatch;
+        private BatchStreamObjectPool<object?> _batchObjectPool = new();
+        private BatchStreamMemoryPool _batchMemoryPool = new();
+        private List<CompositionObject> _objectsForSerialization = new();
         internal ServerCompositor Server => _server;
         internal CompositionEasingFunction DefaultEasing { get; }
-
-        private Compositor(ServerCompositor server)
+        
+        public Compositor(IRenderLoop loop)
         {
-            _server = server;
-            _currentBatch = new Batch();
+            _server = new ServerCompositor(loop, _batchObjectPool, _batchMemoryPool);
             _implicitBatchCommit = ImplicitBatchCommit;
             DefaultEasing = new CubicBezierEasingFunction(this,
                 new Vector2(0.25f, 0.1f), new Vector2(0.25f, 1f));
@@ -40,18 +39,27 @@ namespace Avalonia.Rendering.Composition
 
         public Task RequestCommitAsync()
         {
-            var batch = CurrentBatch;
-            _currentBatch = new Batch();
+            var batch = new Batch();
+            
+            using (var writer = new BatchStreamWriter(batch.Changes, _batchMemoryPool, _batchObjectPool))
+            {
+                foreach (var obj in _objectsForSerialization)
+                {
+                    writer.WriteObject(obj.Server);
+                    obj.SerializeChanges(writer);
+#if DEBUG_COMPOSITOR_SERIALIZATION
+                    writer.Write(BatchStreamDebugMarkers.ObjectEndMagic);
+                    writer.WriteObject(BatchStreamDebugMarkers.ObjectEndMarker);
+#endif
+                }
+                _objectsForSerialization.Clear();
+            }
+            
             batch.CommitedAt = Server.Clock.Elapsed;
             _server.EnqueueBatch(batch);
             return batch.Completed;
         }
 
-        public static Compositor Create(IRenderLoop timer)
-        {
-            return new Compositor(new ServerCompositor(timer));
-        }
-
         public void Dispose()
         {
             
@@ -122,12 +130,8 @@ namespace Avalonia.Rendering.Composition
         public ImplicitAnimationCollection CreateImplicitAnimationCollection() => new ImplicitAnimationCollection(this);
 
         public CompositionAnimationGroup CreateAnimationGroup() => new CompositionAnimationGroup(this);
-
-        internal CustomDrawVisual<T> CreateCustomDrawVisual<T>(ICustomDrawVisualRenderer<T> renderer,
-            ICustomDrawVisualHitTest<T>? hitTest = null) where T : IEquatable<T> =>
-            new CustomDrawVisual<T>(this, renderer, hitTest);
-
-        public void QueueImplicitBatchCommit()
+        
+        private void QueueImplicitBatchCommit()
         {
             if(_implicitBatchCommitQueued)
                 return;
@@ -140,5 +144,11 @@ namespace Avalonia.Rendering.Composition
             _implicitBatchCommitQueued = false;
             RequestCommitAsync();
         }
+
+        internal void RegisterForSerialization(CompositionObject compositionObject)
+        {
+            _objectsForSerialization.Add(compositionObject);
+            QueueImplicitBatchCommit();
+        }
     }
 }

src/Avalonia.Base/Rendering/Composition/ContainerVisual.cs

@@ -2,19 +2,20 @@ using Avalonia.Rendering.Composition.Server;
 
 namespace Avalonia.Rendering.Composition
 {
-    public class CompositionContainerVisual : CompositionVisual
+    public partial class CompositionContainerVisual : CompositionVisual
     {
-        public CompositionVisualCollection Children { get; }
-        internal CompositionContainerVisual(Compositor compositor, ServerCompositionContainerVisual server) : base(compositor, server)
+        public CompositionVisualCollection Children { get; private set; } = null!;
+
+        partial void InitializeDefaultsExtra()
         {
-            Children = new CompositionVisualCollection(this, server.Children);
+            Children = new CompositionVisualCollection(this, Server.Children);
         }
 
-        private protected override void OnRootChanged()
+        private protected override void OnRootChangedCore()
         {
             foreach (var ch in Children)
                 ch.Root = Root;
-            base.OnRootChanged();
+            base.OnRootChangedCore();
         }
     }
 }

src/Avalonia.Base/Rendering/Composition/CustomDrawVisual.cs

@@ -1,56 +0,0 @@
-using System;
-using System.Numerics;
-using Avalonia.Platform;
-using Avalonia.Rendering.Composition.Server;
-using Avalonia.Rendering.Composition.Transport;
-
-namespace Avalonia.Rendering.Composition
-{
-    internal class CustomDrawVisual<TData> : CompositionContainerVisual where TData : IEquatable<TData>
-    {
-        private readonly ICustomDrawVisualHitTest<TData>? _hitTest;
-
-        internal CustomDrawVisual(Compositor compositor, ICustomDrawVisualRenderer<TData> renderer,
-            ICustomDrawVisualHitTest<TData>? hitTest) : base(compositor, 
-            new ServerCustomDrawVisual<TData>(compositor.Server, renderer))
-        {
-            _hitTest = hitTest;
-        }
-
-        private TData? _data;
-
-        static bool Eq(TData? left, TData? right)
-        {
-            if (left == null && right == null)
-                return true;
-            if (left == null)
-                return false;
-            return left.Equals(right);
-        }
-        
-        public TData? Data
-        {
-            get => _data;
-            set
-            {
-                if (!Eq(_data, value))
-                {
-                    ((CustomDrawVisualChanges<TData?>) Changes).Data.Value = value;
-                    _data = value;
-                }
-            }
-        }
-        
-        private protected override IChangeSetPool ChangeSetPool => CustomDrawVisualChanges<TData>.Pool;
-    }
-
-    public interface ICustomDrawVisualRenderer<TData>
-    {
-        void Render(IDrawingContextImpl canvas, TData? data);
-    }
-
-    public interface ICustomDrawVisualHitTest<TData>
-    {
-        bool HitTest(TData data, Vector2 vector2);
-    }
-}

src/Avalonia.Base/Rendering/Composition/Server/ServerCompositionDrawListVisual.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Numerics;
 using Avalonia.Collections.Pooled;
 using Avalonia.Platform;
@@ -35,16 +36,15 @@ internal class ServerCompositionDrawListVisual : ServerCompositionContainerVisua
         }
     }
 
-    protected override void ApplyCore(ChangeSet changes)
+    protected override void DeserializeChangesCore(BatchStreamReader reader, TimeSpan commitedAt)
     {
-        var ch = (DrawListVisualChanges)changes;
-        if (ch.DrawCommandsIsSet)
+        if (reader.Read<byte>() == 1)
         {
             _renderCommands?.Dispose();
-            _renderCommands = ch.AcquireDrawCommands();
+            _renderCommands = reader.ReadObject<CompositionDrawList?>();
             _contentBounds = null;
         }
-        base.ApplyCore(changes);
+        base.DeserializeChangesCore(reader, commitedAt);
     }
 
     protected override void RenderCore(CompositorDrawingContextProxy canvas, Matrix4x4 transform)

src/Avalonia.Base/Rendering/Composition/Server/ServerCompositionTarget.cs

@@ -42,8 +42,8 @@ namespace Avalonia.Rendering.Composition.Server
             else
                 _compositor.RemoveCompositionTarget(this);
         }
-
-        partial void ApplyChangesExtra(CompositionTargetChanges c)
+        
+        partial void DeserializeChangesExtra(BatchStreamReader c)
         {
             _redrawRequested = true;
         }

src/Avalonia.Base/Rendering/Composition/Server/ServerCompositor.cs

@@ -17,10 +17,14 @@ namespace Avalonia.Rendering.Composition.Server
         private List<ServerCompositionTarget> _activeTargets = new();
         private HashSet<IAnimationInstance> _activeAnimations = new();
         private List<IAnimationInstance> _animationsToUpdate = new();
+        private BatchStreamObjectPool<object?> _batchObjectPool;
+        private BatchStreamMemoryPool _batchMemoryPool;
 
-        public ServerCompositor(IRenderLoop renderLoop)
+        public ServerCompositor(IRenderLoop renderLoop, BatchStreamObjectPool<object?> batchObjectPool, BatchStreamMemoryPool batchMemoryPool)
         {
             _renderLoop = renderLoop;
+            _batchObjectPool = batchObjectPool;
+            _batchMemoryPool = batchMemoryPool;
             _renderLoop.Add(this);
         }
 
@@ -45,14 +49,21 @@ namespace Avalonia.Rendering.Composition.Server
                     batch = _batches.Dequeue();
                 }
 
-                foreach (var change in batch.Changes)
+                using (var stream = new BatchStreamReader(batch.Changes, _batchMemoryPool, _batchObjectPool))
                 {
-                    if (change.Dispose)
+                    while (!stream.IsObjectEof)
                     {
-                        //TODO
+                        var target = (ServerObject)stream.ReadObject()!;
+                        target.DeserializeChanges(stream, batch);
+#if DEBUG_COMPOSITOR_SERIALIZATION
+                        if (stream.ReadObject() != BatchStreamDebugMarkers.ObjectEndMarker)
+                            throw new InvalidOperationException(
+                                $"Object {target.GetType()} failed to deserialize properly on object stream");
+                        if(stream.Read<Guid>() != BatchStreamDebugMarkers.ObjectEndMagic)
+                            throw new InvalidOperationException(
+                                $"Object {target.GetType()} failed to deserialize properly on data stream");
+#endif
                     }
-                    change.Target!.Apply(change);
-                    change.Reset();
                 }
 
                 _reusableToCompleteList.Add(batch);

src/Avalonia.Base/Rendering/Composition/Server/ServerContainerVisual.cs

@@ -3,10 +3,9 @@ using Avalonia.Platform;
 
 namespace Avalonia.Rendering.Composition.Server
 {
-    internal class ServerCompositionContainerVisual : ServerCompositionVisual
+    internal partial class ServerCompositionContainerVisual : ServerCompositionVisual
     {
-        public ServerCompositionVisualCollection Children { get; }
-        
+        public ServerCompositionVisualCollection Children { get; private set; } = null!;
         
         protected override void RenderCore(CompositorDrawingContextProxy canvas, Matrix4x4 transform)
         {
@@ -28,9 +27,9 @@ namespace Avalonia.Rendering.Composition.Server
                 child.Update(root, GlobalTransformMatrix);
         }
 
-        public ServerCompositionContainerVisual(ServerCompositor compositor) : base(compositor)
+        partial void Initialize()
         {
-            Children = new ServerCompositionVisualCollection(compositor);
+            Children = new ServerCompositionVisualCollection(Compositor);
         }
     }
 }

src/Avalonia.Base/Rendering/Composition/Server/ServerCustomDrawVisual.cs

@@ -1,31 +0,0 @@
-using System.Numerics;
-using Avalonia.Platform;
-using Avalonia.Rendering.Composition.Transport;
-
-namespace Avalonia.Rendering.Composition.Server
-{
-    class ServerCustomDrawVisual<TData> : ServerCompositionContainerVisual
-    {
-        private readonly ICustomDrawVisualRenderer<TData> _renderer;
-        private TData? _data;
-        public ServerCustomDrawVisual(ServerCompositor compositor, ICustomDrawVisualRenderer<TData> renderer) : base(compositor)
-        {
-            _renderer = renderer;
-        }
-
-        protected override void ApplyCore(ChangeSet changes)
-        {
-            var c = (CustomDrawVisualChanges<TData>) changes;
-            if (c.Data.IsSet)
-                _data = c.Data.Value;
-            
-            base.ApplyCore(changes);
-        }
-
-        protected override void RenderCore(CompositorDrawingContextProxy canvas, Matrix4x4 transform)
-        {
-            _renderer.Render(canvas, _data);
-            base.RenderCore(canvas, transform);
-        }
-    }
-}

src/Avalonia.Base/Rendering/Composition/Server/ServerList.cs

@@ -7,25 +7,19 @@ namespace Avalonia.Rendering.Composition.Server
     class ServerList<T> : ServerObject where T : ServerObject
     {
         public List<T> List { get; } = new List<T>();
-        protected override void ApplyCore(ChangeSet changes)
+
+        protected override void DeserializeChangesCore(BatchStreamReader reader, TimeSpan commitedAt)
         {
-            var c = (ListChangeSet<T>) changes;
-            if (c.HasListChanges)
+            if (reader.Read<byte>() == 1)
             {
-                foreach (var lc in c.ListChanges)
-                {
-                    if(lc.Action == ListChangeAction.Clear)
-                        List.Clear();
-                    if(lc.Action == ListChangeAction.RemoveAt)
-                        List.RemoveAt(lc.Index);
-                    if(lc.Action == ListChangeAction.InsertAt)
-                        List.Insert(lc.Index, lc.Added!);
-                    if (lc.Action == ListChangeAction.ReplaceAt)
-                        List[lc.Index] = lc.Added!;
-                }
+                List.Clear();
+                var count = reader.Read<int>();
+                for (var c = 0; c < count; c++) 
+                    List.Add(reader.ReadObject<T>());
             }
+            base.DeserializeChangesCore(reader, commitedAt);
         }
-        
+
         public override long LastChangedBy
         {
             get

src/Avalonia.Base/Rendering/Composition/Server/ServerObject.cs

@@ -23,18 +23,6 @@ namespace Avalonia.Rendering.Composition.Server
             Compositor = compositor;
         }
 
-        protected virtual void ApplyCore(ChangeSet changes)
-        {
-            
-        }
-
-        public void Apply(ChangeSet changes)
-        {
-            ApplyCore(changes);
-            ValuesInvalidated();
-            ItselfLastChangedBy = changes.Batch!.SequenceId;
-        }
-
         public virtual ExpressionVariant GetPropertyForAnimation(string name)
         {
             return default;
@@ -81,6 +69,10 @@ namespace Avalonia.Rendering.Composition.Server
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         private ref ServerObjectSubscriptionStore GetStoreFromOffset(int offset)
         {
+#if DEBUG
+            if (offset == 0)
+                throw new InvalidOperationException();
+#endif
             return ref Unsafe.As<uint, ServerObjectSubscriptionStore>(ref Unsafe.AddByteOffset(ref _activationCount,
                 new IntPtr(offset)));
         }
@@ -112,5 +104,17 @@ namespace Avalonia.Rendering.Composition.Server
         }
 
         public virtual int? GetFieldOffset(string fieldName) => null;
+
+        protected virtual void DeserializeChangesCore(BatchStreamReader reader, TimeSpan commitedAt)
+        {
+            
+        }
+        
+        public void DeserializeChanges(BatchStreamReader reader, Batch batch)
+        {
+            DeserializeChangesCore(reader, batch.CommitedAt);
+            ValuesInvalidated();
+            ItselfLastChangedBy = batch.SequenceId;
+        }
     }
 }

src/Avalonia.Base/Rendering/Composition/Server/ServerVisual.cs

@@ -7,7 +7,6 @@ namespace Avalonia.Rendering.Composition.Server
     unsafe partial class ServerCompositionVisual : ServerObject
     {
         private bool _isDirty;
-        private ServerCompositionTarget? _root;
         private bool _isBackface;
         protected virtual void RenderCore(CompositorDrawingContextProxy canvas, Matrix4x4 transform)
         {
@@ -119,28 +118,24 @@ namespace Avalonia.Rendering.Composition.Server
             public bool Visible;
         }
 
-        partial void ApplyChangesExtra(CompositionVisualChanges c)
+        
+        partial void DeserializeChangesExtra(BatchStreamReader c)
         {
-            if (c.Parent.IsSet)
-                Parent = c.Parent.Value;
-            if (c.Root.IsSet)
-                Root = c.Root.Value;
             ValuesInvalidated();
         }
 
-        public ServerCompositionTarget? Root
+        partial void OnRootChanging()
         {
-            get => _root;
-            private set
-            {
-                if(_root != null)
-                    Deactivate();
-                _root = value;
-                if (_root != null)
-                    Activate();
-            }
+            if(Root != null)
+                Deactivate();
         }
-
+        
+        partial void OnRootChanged()
+        {
+            if (Root != null)
+                Activate();
+        }
+        
         protected override void ValuesInvalidated()
         {
             _isDirty = true;
@@ -149,8 +144,6 @@ namespace Avalonia.Rendering.Composition.Server
             else
                 Root?.Invalidate();
         }
-
-        public ServerCompositionVisual? Parent { get; private set; }
         public bool IsVisibleInFrame { get; set; }
         public Rect TransformedBounds { get; set; }
         public virtual Rect ContentBounds => new Rect(0, 0, Size.X, Size.Y);

src/Avalonia.Base/Rendering/Composition/Transport/Batch.cs

@@ -9,23 +9,22 @@ namespace Avalonia.Rendering.Composition.Transport
     internal class Batch
     {
         private static long _nextSequenceId = 1;
-        private static ConcurrentBag<List<ChangeSet>> _pool = new ConcurrentBag<List<ChangeSet>>();
+        private static ConcurrentBag<BatchStreamData> _pool = new();
         public long SequenceId { get; }
         
         public Batch()
         {
             SequenceId = Interlocked.Increment(ref _nextSequenceId);
             if (!_pool.TryTake(out var lst))
-                lst = new List<ChangeSet>();
+                lst = new BatchStreamData();
             Changes = lst;
         }
         private TaskCompletionSource<int> _tcs = new TaskCompletionSource<int>();
-        public List<ChangeSet> Changes { get; private set; }
+        public BatchStreamData Changes { get; private set; }
         public TimeSpan CommitedAt { get; set; }
         
         public void Complete()
         {
-            Changes.Clear();
             _pool.Add(Changes);
             Changes = null!;
 

src/Avalonia.Base/Rendering/Composition/Transport/BatchStream.cs

@@ -2,13 +2,14 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Runtime.CompilerServices;
+using Avalonia.Rendering.Composition.Animations;
 using Avalonia.Rendering.Composition.Server;
 
 namespace Avalonia.Rendering.Composition.Transport;
 
 internal class BatchStreamData
 {
-    public Queue<BatchStreamSegment<ServerObject[]>> Objects { get; } = new();
+    public Queue<BatchStreamSegment<object?[]>> Objects { get; } = new();
     public Queue<BatchStreamSegment<IntPtr>> Structs { get; } = new();
 }
 
@@ -22,12 +23,12 @@ internal class BatchStreamWriter : IDisposable
 {
     private readonly BatchStreamData _output;
     private readonly BatchStreamMemoryPool _memoryPool;
-    private readonly BatchStreamObjectPool<ServerObject> _objectPool;
+    private readonly BatchStreamObjectPool<object?> _objectPool;
 
-    private BatchStreamSegment<ServerObject[]?> _currentObjectSegment;
+    private BatchStreamSegment<object?[]?> _currentObjectSegment;
     private BatchStreamSegment<IntPtr> _currentDataSegment;
     
-    public BatchStreamWriter(BatchStreamData output, BatchStreamMemoryPool memoryPool, BatchStreamObjectPool<ServerObject> objectPool)
+    public BatchStreamWriter(BatchStreamData output, BatchStreamMemoryPool memoryPool, BatchStreamObjectPool<object?> objectPool)
     {
         _output = output;
         _memoryPool = memoryPool;
@@ -69,7 +70,7 @@ internal class BatchStreamWriter : IDisposable
         _currentDataSegment.ElementCount += size;
     }
 
-    public void Write(ServerObject item)
+    public void WriteObject(object? item)
     {
         if (_currentObjectSegment.Data == null ||
             _currentObjectSegment.ElementCount >= _currentObjectSegment.Data.Length)
@@ -89,15 +90,15 @@ internal class BatchStreamReader : IDisposable
 {
     private readonly BatchStreamData _input;
     private readonly BatchStreamMemoryPool _memoryPool;
-    private readonly BatchStreamObjectPool<ServerObject> _objectPool;
+    private readonly BatchStreamObjectPool<object?> _objectPool;
 
-    private BatchStreamSegment<ServerObject[]?> _currentObjectSegment;
+    private BatchStreamSegment<object?[]?> _currentObjectSegment;
     private BatchStreamSegment<IntPtr> _currentDataSegment;
     private int _memoryOffset, _objectOffset;
     
-    public BatchStreamReader(BatchStreamData _input, BatchStreamMemoryPool memoryPool, BatchStreamObjectPool<ServerObject> objectPool)
+    public BatchStreamReader(BatchStreamData input, BatchStreamMemoryPool memoryPool, BatchStreamObjectPool<object?> objectPool)
     {
-        this._input = _input;
+        _input = input;
         _memoryPool = memoryPool;
         _objectPool = objectPool;
     }
@@ -116,7 +117,7 @@ internal class BatchStreamReader : IDisposable
         if (_memoryOffset + size > _currentDataSegment.ElementCount)
             throw new InvalidOperationException("Attempted to read more memory then left in the current segment");
 
-        var rv = *(T*)((byte*)_currentDataSegment.Data + size);
+        var rv = *(T*)((byte*)_currentDataSegment.Data + _memoryOffset);
         _memoryOffset += size;
         if (_memoryOffset == _currentDataSegment.ElementCount)
         {
@@ -127,7 +128,9 @@ internal class BatchStreamReader : IDisposable
         return rv;
     }
 
-    public ServerObject ReadObject()
+    public T ReadObject<T>() where T : class? => (T)ReadObject()!;
+    
+    public object? ReadObject()
     {
         if (_currentObjectSegment.Data == null)
         {
@@ -148,6 +151,8 @@ internal class BatchStreamReader : IDisposable
         return rv;
     }
 
+    public bool IsObjectEof => _currentObjectSegment.Data == null && _input.Objects.Count == 0;
+    
     public bool IsStructEof => _currentDataSegment.Data == IntPtr.Zero && _input.Structs.Count == 0;
     
     public void Dispose()

src/Avalonia.Base/Rendering/Composition/Transport/BatchStreamArrayPool.cs

@@ -18,27 +18,31 @@ internal abstract class BatchStreamPoolBase<T> : IDisposable
     readonly int[] _usageStatistics = new int[10];
     int _usageStatisticsSlot;
 
-    public BatchStreamPoolBase(bool needsFinalize = false)
+    public BatchStreamPoolBase(bool needsFinalize, Action<Func<bool>>? startTimer = null)
     {
         if(!needsFinalize)
             GC.SuppressFinalize(needsFinalize);
 
         var updateRef = new WeakReference<BatchStreamPoolBase<T>>(this);
-        StartUpdateTimer(updateRef);
+        StartUpdateTimer(startTimer, updateRef);
     }
 
-    static void StartUpdateTimer(WeakReference<BatchStreamPoolBase<T>> updateRef)
+    static void StartUpdateTimer(Action<Func<bool>>? startTimer, WeakReference<BatchStreamPoolBase<T>> updateRef)
     {
-        DispatcherTimer.Run(() =>
+        Func<bool> timerProc = () =>
         {
             if (updateRef.TryGetTarget(out var target))
             {
                 target.UpdateStatistics();
                 return true;
             }
-            return false;
 
-        }, TimeSpan.FromSeconds(1));
+            return false;
+        };
+        if (startTimer != null)
+            startTimer(timerProc);
+        else
+            DispatcherTimer.Run(timerProc, TimeSpan.FromSeconds(1));
     }
 
     private void UpdateStatistics()
@@ -50,7 +54,7 @@ internal abstract class BatchStreamPoolBase<T> : IDisposable
             while (recentlyUsedPooledSlots < _pool.Count) 
                 DestroyItem(_pool.Pop());
 
-            _usageStatistics[_usage] = 0;
+            _usageStatistics[_usageStatisticsSlot] = 0;
             _usageStatisticsSlot = (_usageStatisticsSlot + 1) % _usageStatistics.Length;
         }
     }
@@ -109,11 +113,11 @@ internal abstract class BatchStreamPoolBase<T> : IDisposable
     }
 }
 
-internal sealed class BatchStreamObjectPool<T> : BatchStreamPoolBase<T[]> where T : class
+internal sealed class BatchStreamObjectPool<T> : BatchStreamPoolBase<T[]> where T : class?
 {
     private readonly int _arraySize;
 
-    public BatchStreamObjectPool(int arraySize = 1024)
+    public BatchStreamObjectPool(int arraySize = 1024, Action<Func<bool>>? startTimer = null) : base(false, startTimer)
     {
         _arraySize = arraySize;
     }
@@ -133,7 +137,7 @@ internal sealed class BatchStreamMemoryPool : BatchStreamPoolBase<IntPtr>
 {
     public int BufferSize { get; }
 
-    public BatchStreamMemoryPool(int bufferSize = 16384)
+    public BatchStreamMemoryPool(int bufferSize = 16384, Action<Func<bool>>? startTimer = null) : base(true, startTimer)
     {
         BufferSize = bufferSize;
     }

src/Avalonia.Base/Rendering/Composition/Transport/BatchStreamDebugMarker.cs

@@ -0,0 +1,9 @@
+using System;
+
+namespace Avalonia.Rendering.Composition.Transport;
+
+internal class BatchStreamDebugMarkers
+{
+    public static object ObjectEndMarker = new object();
+    public static Guid ObjectEndMagic = Guid.NewGuid();
+}

src/Avalonia.Base/Rendering/Composition/Transport/Change.cs

@@ -1,82 +0,0 @@
-using System;
-using System.Diagnostics.CodeAnalysis;
-using Avalonia.Rendering.Composition.Animations;
-
-namespace Avalonia.Rendering.Composition.Transport
-{
-    struct Change<T>
-    {
-        private T? _value;
-
-        public bool IsSet { get; private set; }
-
-        public T? Value
-        {
-            get
-            {
-                if(!IsSet)
-                    throw new InvalidOperationException();
-                return _value;
-            }
-            set
-            {
-                IsSet = true;
-                _value = value;
-            }
-        }
-
-        public void Reset()
-        {
-            _value = default;
-            IsSet = false;
-        }
-    }
-
-    struct AnimatedChange<T>
-    {
-        private T? _value;
-        private IAnimationInstance? _animation;
-
-        public bool IsValue { get; private set; }
-        public bool IsAnimation { get; private set; }
-
-        public T Value
-        {
-            get
-            {
-                if(!IsValue)
-                    throw new InvalidOperationException();
-                return _value!;
-            }
-            set
-            {
-                IsAnimation = false;
-                _animation = null;
-                IsValue = true;
-                _value = value;
-            }
-        }
-        
-        public IAnimationInstance Animation
-        {
-            get
-            {
-                if(!IsAnimation)
-                    throw new InvalidOperationException();
-                return _animation!;
-            }
-            set
-            {
-                IsValue = false;
-                _value = default;
-                IsAnimation = true;
-                _animation = value;
-            }
-        }
-
-        public void Reset()
-        {
-            this = default;
-        }
-    }
-}

src/Avalonia.Base/Rendering/Composition/Transport/ChangeSet.cs

@@ -1,36 +0,0 @@
-using Avalonia.Rendering.Composition.Server;
-
-namespace Avalonia.Rendering.Composition.Transport
-{
-    internal abstract class ChangeSet
-    {
-        private readonly IChangeSetPool _pool;
-        public Batch Batch = null!;
-        public ServerObject? Target;
-        public bool Dispose;
-
-        public ChangeSet(IChangeSetPool pool)
-        {
-            _pool = pool;
-        }
-
-        public virtual void Reset()
-        {
-            Batch = null!;
-            Target = null;
-            Dispose = false;
-        }
-
-        public void Return()
-        {
-            _pool.Return(this);
-        }
-    }
-
-    internal class CompositionObjectChanges : ChangeSet
-    {
-        public CompositionObjectChanges(IChangeSetPool pool) : base(pool)
-        {
-        }
-    }
-}

src/Avalonia.Base/Rendering/Composition/Transport/ChangeSetPool.cs

@@ -1,42 +0,0 @@
-using System;
-using System.Collections.Concurrent;
-using Avalonia.Rendering.Composition.Server;
-
-namespace Avalonia.Rendering.Composition.Transport
-{
-    interface IChangeSetPool
-    {
-        void Return(ChangeSet changes);
-        ChangeSet Get(ServerObject target, Batch batch);
-    }
-    
-    class ChangeSetPool<T> : IChangeSetPool where T : ChangeSet
-    {
-        private readonly Func<IChangeSetPool, T> _factory;
-        private readonly ConcurrentBag<T> _pool = new ConcurrentBag<T>();
-
-        public ChangeSetPool(Func<IChangeSetPool, T> factory)
-        {
-            _factory = factory;
-        }
-
-        public void Return(T changes)
-        {
-            changes.Reset();
-            _pool.Add(changes);
-        }
-
-        void IChangeSetPool.Return(ChangeSet changes) => Return((T) changes);
-        ChangeSet IChangeSetPool.Get(ServerObject target, Batch batch) => Get(target, batch);
-        
-        public T Get(ServerObject target, Batch batch)
-        {
-            if (!_pool.TryTake(out var res))
-                res = _factory(this);
-            res.Target = target;
-            res.Batch = batch;
-            res.Dispose = false;
-            return res;
-        }
-    }
-}

src/Avalonia.Base/Rendering/Composition/Transport/CompositionTargetChanges.cs

@@ -1,11 +0,0 @@
-namespace Avalonia.Rendering.Composition.Transport;
-
-partial class CompositionTargetChanges
-{
-    public Change<bool> RedrawRequested;
-
-    partial void ResetExtra()
-    {
-        RedrawRequested.Reset();
-    }
-}

src/Avalonia.Base/Rendering/Composition/Transport/CustomDrawVisualChanges.cs

@@ -1,20 +0,0 @@
-namespace Avalonia.Rendering.Composition.Transport
-{
-    class CustomDrawVisualChanges<TData> : CompositionVisualChanges
-    {
-        public CustomDrawVisualChanges(IChangeSetPool pool) : base(pool)
-        {
-        }
-
-        public Change<TData> Data;
-
-        public override void Reset()
-        {
-            Data.Reset();
-            base.Reset();
-        }
-
-        public new static ChangeSetPool<CustomDrawVisualChanges<TData>> Pool { get; } =
-            new ChangeSetPool<CustomDrawVisualChanges<TData>>(pool => new CustomDrawVisualChanges<TData>(pool));
-    }
-}

src/Avalonia.Base/Rendering/Composition/Transport/DrawListVisualChanges.cs

@@ -1,48 +0,0 @@
-using System.Collections.Generic;
-using Avalonia.Collections.Pooled;
-using Avalonia.Rendering.Composition.Drawing;
-using Avalonia.Rendering.SceneGraph;
-using Avalonia.Utilities;
-
-namespace Avalonia.Rendering.Composition.Transport;
-
-internal class DrawListVisualChanges : CompositionVisualChanges
-{
-    private CompositionDrawList? _drawCommands;
-
-    public DrawListVisualChanges(IChangeSetPool pool) : base(pool)
-    {
-    }
-
-    public CompositionDrawList? DrawCommands
-    {
-        get => _drawCommands;
-        set
-        {
-            _drawCommands?.Dispose();
-            _drawCommands = value;
-            DrawCommandsIsSet = true;
-        }
-    }
-    
-    public bool DrawCommandsIsSet { get; private set; }
-
-    public CompositionDrawList? AcquireDrawCommands()
-    {
-        var rv = _drawCommands;
-        _drawCommands = null;
-        DrawCommandsIsSet = false;
-        return rv;
-    }
-
-    public override void Reset()
-    {
-        _drawCommands?.Dispose();
-        _drawCommands = null;
-        DrawCommandsIsSet = false;
-        base.Reset();
-    }
-
-    public new static ChangeSetPool<DrawListVisualChanges> Pool { get; } =
-        new ChangeSetPool<DrawListVisualChanges>(pool => new(pool));
-}

src/Avalonia.Base/Rendering/Composition/Transport/ListChange.cs

@@ -1,19 +0,0 @@
-using Avalonia.Rendering.Composition.Server;
-
-namespace Avalonia.Rendering.Composition.Transport
-{
-    internal class ListChange<T> where T : ServerObject
-    {
-        public int Index;
-        public ListChangeAction Action;
-        public T? Added;
-    }
-
-    internal enum ListChangeAction
-    {
-        InsertAt,
-        RemoveAt,
-        Clear,
-        ReplaceAt
-    }
-}

src/Avalonia.Base/Rendering/Composition/Transport/ListChangeSet.cs

@@ -1,25 +0,0 @@
-using System.Collections.Generic;
-using Avalonia.Rendering.Composition.Server;
-
-namespace Avalonia.Rendering.Composition.Transport
-{
-    class ListChangeSet<T> : ChangeSet where T : ServerObject
-    {
-        private List<ListChange<T>>? _listChanges;
-        public List<ListChange<T>> ListChanges => _listChanges ??= new List<ListChange<T>>();
-        public bool HasListChanges => _listChanges != null;
-
-        public override void Reset()
-        {
-            _listChanges?.Clear();
-            base.Reset();
-        }
-
-        public ListChangeSet(IChangeSetPool pool) : base(pool)
-        {
-        }
-
-        public static readonly ChangeSetPool<ListChangeSet<T>> Pool =
-            new ChangeSetPool<ListChangeSet<T>>(pool => new ListChangeSet<T>(pool));
-    }
-}

src/Avalonia.Base/Rendering/Composition/Transport/ServerListProxyHelper.cs

@@ -8,19 +8,21 @@ namespace Avalonia.Rendering.Composition.Transport
         where TServer : ServerObject
         where TClient : CompositionObject
     {
-        private readonly IGetChanges _parent;
-        private readonly List<TClient> _list = new List<TClient>();
+        private readonly IRegisterForSerialization _parent;
+        private bool _changed;
 
-        public interface IGetChanges
+        public interface IRegisterForSerialization
         {
-            ListChangeSet<TServer> GetChanges();
+            void RegisterForSerialization();
         }
 
-        public ServerListProxyHelper(IGetChanges parent)
+        public ServerListProxyHelper(IRegisterForSerialization parent)
         {
             _parent = parent;
         }
-
+        
+        private readonly List<TClient> _list = new List<TClient>();
+        
         IEnumerator<TClient> IEnumerable<TClient>.GetEnumerator() => GetEnumerator();
         public List<TClient>.Enumerator GetEnumerator() => _list.GetEnumerator();
         IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
@@ -30,10 +32,8 @@ namespace Avalonia.Rendering.Composition.Transport
         public void Clear()
         {
             _list.Clear();
-            _parent.GetChanges().ListChanges.Add(new ListChange<TServer>
-            {
-                Action = ListChangeAction.Clear
-            });
+            _changed = true;
+            _parent.RegisterForSerialization();
         }
 
         public bool Contains(TClient item) => _list.Contains(item);
@@ -56,22 +56,15 @@ namespace Avalonia.Rendering.Composition.Transport
         public void Insert(int index, TClient item)
         {
             _list.Insert(index, item);
-            _parent.GetChanges().ListChanges.Add(new ListChange<TServer>
-            {
-                Action = ListChangeAction.InsertAt,
-                Index = index,
-                Added = (TServer) item.Server
-            });
+            _changed = true;
+            _parent.RegisterForSerialization();
         }
 
         public void RemoveAt(int index)
         {
             _list.RemoveAt(index);
-            _parent.GetChanges().ListChanges.Add(new ListChange<TServer>
-            {
-                Action = ListChangeAction.RemoveAt,
-                Index = index
-            });
+            _changed = true;
+            _parent.RegisterForSerialization();
         }
 
         public TClient this[int index]
@@ -80,13 +73,21 @@ namespace Avalonia.Rendering.Composition.Transport
             set
             {
                 _list[index] = value;
-                _parent.GetChanges().ListChanges.Add(new ListChange<TServer>
-                {
-                    Action = ListChangeAction.ReplaceAt,
-                    Index = index,
-                    Added = (TServer) value.Server
-                });
+                _changed = true;
+                _parent.RegisterForSerialization();
+            }
+        }
+
+        public void Serialize(BatchStreamWriter writer)
+        {
+            writer.Write((byte)(_changed ? 1 : 0));
+            if (_changed)
+            {
+                writer.Write(_list.Count);
+                foreach (var el in _list)
+                    writer.WriteObject(el.Server);
             }
+            _changed = false;
         }
     }
 }

src/Avalonia.Base/Rendering/Composition/Transport/VisualChanges.cs

@@ -1,16 +0,0 @@
-using Avalonia.Rendering.Composition.Server;
-
-namespace Avalonia.Rendering.Composition.Transport
-{
-    partial class CompositionVisualChanges
-    {
-        public Change<ServerCompositionVisual> Parent;
-        public Change<ServerCompositionTarget> Root;
-
-        partial void ResetExtra()
-        {
-            Parent.Reset();
-            Root.Reset();
-        }
-    }
-}

src/Avalonia.Base/Rendering/Composition/Visual.cs

@@ -4,39 +4,14 @@ namespace Avalonia.Rendering.Composition
 {
     public abstract partial class CompositionVisual
     {
-        private CompositionVisual? _parent;
-        private CompositionTarget? _root;
-
-        public CompositionVisual? Parent
-        {
-            get => _parent;
-            internal set
-            {
-                if (_parent == value)
-                    return;
-                _parent = value;
-                Changes.Parent.Value = value?.Server;
-                Root = _parent?.Root;
-            }
-        }
-        
-        // TODO: hide behind private-ish API
-        public CompositionTarget? Root
+        private protected virtual void OnRootChangedCore()
         {
-            get => _root;
-            internal set
-            {
-                var changed = _root != value;
-                _root = value;
-                Changes.Root.Value = value?.Server;
-                if (changed)
-                    OnRootChanged();
-            }
         }
 
-        private protected virtual void OnRootChanged()
-        {
-        }
+        partial void OnRootChanged() => OnRootChangedCore();
+
+        partial void OnParentChanged() => Root = Parent?.Root;
+
 
         internal Matrix4x4? TryGetServerTransform()
         {

src/Avalonia.Base/Rendering/Composition/VisualCollection.cs

@@ -64,6 +64,7 @@ namespace Avalonia.Rendering.Composition
         {
             if (item.Parent != null)
                 throw new InvalidOperationException("Visual already has a parent");
+            item.Parent = item;
         }
     }
 }

src/Avalonia.Base/composition-schema.xml

@@ -4,10 +4,12 @@
     <Using>Avalonia.Rendering.Composition.Server</Using>
     <Using>Avalonia.Rendering.Composition.Transport</Using>
     <Using>Avalonia.Rendering.Composition.Animations</Using>
-
-    <Manual Name="CompositionContainerVisual" />
+    
+    <Manual Name="Avalonia.Platform.IGeometryImpl" Passthrough="true"/>
     <Manual Name="ICompositionSurface" ServerName="ServerCompositionSurface" />
     <Object Name="CompositionVisual" Abstract="true">
+        <Property Name="Root" Type="CompositionTarget?" InternalSet="true" />
+        <Property Name="Parent" Type="CompositionVisual?" InternalSet="true"  />
         <Property Name="Visible" Type="bool" Animated="true" DefaultValue="true"/>
         <Property Name="Opacity" Type="float" Animated="true" DefaultValue="1"/>
         <Property Name="Clip" Type="Avalonia.Platform.IGeometryImpl?" />
@@ -21,6 +23,7 @@
         <Property Name="Scale" Type="Vector3" DefaultValue="new Vector3(1, 1, 1)" Animated="true"/>
         <Property Name="TransformMatrix" Type="Matrix4x4" DefaultValue="Matrix4x4.Identity" Animated="true"/>
     </Object>
+    <Object Name="CompositionContainerVisual" Inherits="CompositionVisual"/>
     <List Name="CompositionVisualCollection" ItemType="CompositionVisual" CustomCtor="true"/>
     <Object Name="CompositionTarget" CustomServerCtor="true">
         <Property Name="Root" Type="CompositionVisual?"/>

src/Avalonia.SourceGenerator/CompositionGenerator/Config.cs

@@ -35,6 +35,10 @@ namespace Avalonia.SourceGenerator.CompositionGenerator
         [XmlAttribute]
         public string Name { get; set; }
         
+        
+        [XmlAttribute]
+        public bool Passthrough { get; set; }
+        
         [XmlAttribute]
         public string ServerName { get; set; }
     }
@@ -104,6 +108,8 @@ namespace Avalonia.SourceGenerator.CompositionGenerator
         public string DefaultValue { get; set; }
         [XmlAttribute]
         public bool Animated { get; set; }
+        [XmlAttribute]
+        public bool InternalSet { get; set; }
     }
 
     public class GAnimationType

src/Avalonia.SourceGenerator/CompositionGenerator/Extensions.cs

@@ -41,6 +41,15 @@ namespace Avalonia.SourceGenerator.CompositionGenerator
                 return cl;
             return cl.AddModifiers(modifiers.Select(x => SyntaxFactory.Token(x)).ToArray());
         }
+        
+        public static EnumDeclarationSyntax AddModifiers(this EnumDeclarationSyntax cl, params SyntaxKind[] modifiers)
+        {
+            if (modifiers == null)
+                return cl;
+            return cl.AddModifiers(modifiers.Select(x => SyntaxFactory.Token(x)).ToArray());
+        }
+        
+        
 
         public static string WithLowerFirst(this string s)
         {

src/Avalonia.SourceGenerator/CompositionGenerator/Generator.KeyFrameAnimation.cs

@@ -25,7 +25,7 @@ namespace Avalonia.Rendering.Composition
 
         internal override IAnimationInstance CreateInstance(Avalonia.Rendering.Composition.Server.ServerObject targetObject, ExpressionVariant? finalValue)
         {{
-            return new KeyFrameAnimationInstance<{a.Type}>({name}Interpolator.Instance, _keyFrames.Snapshot(), CreateSnapshot(true), 
+            return new KeyFrameAnimationInstance<{a.Type}>({name}Interpolator.Instance, _keyFrames.Snapshot(), CreateSnapshot(), 
                 finalValue?.CastOrDefault<{a.Type}>(), targetObject,
                 DelayBehavior, DelayTime, Direction, Duration, IterationBehavior,
                 IterationCount, StopBehavior);

src/Avalonia.SourceGenerator/CompositionGenerator/Generator.ListProxy.cs

@@ -11,9 +11,7 @@ class Template
 {
         private ServerListProxyHelper<ItemTypeName, ServerItemTypeName> _list = null!;
 
-        ListChangeSet<ServerItemTypeName>
-            ServerListProxyHelper<ItemTypeName, ServerItemTypeName>.IGetChanges.
-            GetChanges() => Changes;
+        void ServerListProxyHelper<ItemTypeName, ServerItemTypeName>.IRegisterForSerialization.RegisterForSerialization() => RegisterForSerialization();
 
         public List<ItemTypeName>.Enumerator GetEnumerator() => _list.GetEnumerator();
 
@@ -87,7 +85,11 @@ class Template
         partial void OnBeforeReplace(ItemTypeName oldItem, ItemTypeName newItem);
         partial void OnReplace(ItemTypeName oldItem, ItemTypeName newItem);
         partial void OnClear();
-}
+        private protected override void SerializeChangesCore(BatchStreamWriter writer)
+        {{
+            _list.Serialize(writer);
+            base.SerializeChangesCore(writer);
+        }}
 ";
 
         private ClassDeclarationSyntax AppendListProxy(GList list, ClassDeclarationSyntax cl)
@@ -97,7 +99,7 @@ class Template
             var serverItemType = ServerName(itemType);
 
             cl = cl.AddBaseListTypes(SimpleBaseType(
-                    ParseTypeName("ServerListProxyHelper<" + itemType + ", " + serverItemType + ">.IGetChanges")),
+                    ParseTypeName("ServerListProxyHelper<" + itemType + ", " + serverItemType + ">.IRegisterForSerialization")),
                 SimpleBaseType(ParseTypeName("IList<" + itemType + ">"))
             );
             var code = ListProxyTemplate.Replace("ListTypeName", list.Name)

src/Avalonia.SourceGenerator/CompositionGenerator/Generator.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using Microsoft.CodeAnalysis;
@@ -38,7 +39,12 @@ namespace Avalonia.SourceGenerator.CompositionGenerator
 
         string ServerName(string c) => c != null ? ("Server" + c) : "ServerObject";
         string ChangesName(string c) => c != null ? (c + "Changes") : "ChangeSet";
-        
+        string ChangedFieldsTypeName(GClass c) => c.Name + "ChangedFields";
+        string ChangedFieldsFieldName(GClass c) =>  "_changedFieldsOf" + c.Name;
+        string PropertyBackingFieldName(GProperty prop) => "_" + prop.Name.WithLowerFirst();
+        string ServerPropertyOffsetFieldName(GProperty prop) => "s_OffsetOf" + PropertyBackingFieldName(prop);
+        string PropertyPendingAnimationFieldName(GProperty prop) => "_pendingAnimationFor" + prop.Name;
+
         void GenerateClass(GClass cl)
         {
             var list = cl as GList;
@@ -68,36 +74,13 @@ namespace Avalonia.SourceGenerator.CompositionGenerator
                 .WithBaseType(serverBase);
 
             string changesName = ChangesName(cl.Name);
-            var changesBase = ChangesName(cl.ChangesBase ?? cl.Inherits);
+            string changedFieldsTypeName = ChangedFieldsTypeName(cl);
+            string changedFieldsName = ChangedFieldsFieldName(cl);
 
-            if (list != null)
-                changesBase = "ListChangeSet<" + ServerName(list.ItemType) + ">";
-
-            var changeSetPoolType = "ChangeSetPool<" + changesName + ">";
-            var transport = ClassDeclaration(changesName)
-                .AddModifiers(SyntaxKind.UnsafeKeyword, SyntaxKind.PartialKeyword)
-                .WithBaseType(changesBase)
-                .AddMembers(DeclareField(changeSetPoolType, "Pool",
-                    EqualsValueClause(
-                        ParseExpression($"new {changeSetPoolType}(pool => new {changesName}(pool))")
-                    ),
-                    SyntaxKind.PublicKeyword,
-                    SyntaxKind.StaticKeyword, SyntaxKind.ReadOnlyKeyword))
-                .AddMembers(ParseMemberDeclaration($"public {changesName}(IChangeSetPool pool) : base(pool){{}}"));
-
-            client = client
-                .AddMembers(
-                    PropertyDeclaration(ParseTypeName("IChangeSetPool"), "ChangeSetPool")
-                    .AddModifiers(SyntaxKind.PrivateKeyword, SyntaxKind.ProtectedKeyword,
-                            SyntaxKind.OverrideKeyword)
-                        .WithExpressionBody(
-                            ArrowExpressionClause(MemberAccess(changesName, "Pool")))
-                        .WithSemicolonToken(Semicolon()))
-                .AddMembers(PropertyDeclaration(ParseTypeName(changesName), "Changes")
-                    .AddModifiers(SyntaxKind.PrivateKeyword, SyntaxKind.NewKeyword)
-                    .WithExpressionBody(ArrowExpressionClause(CastExpression(ParseTypeName(changesName),
-                        MemberAccess(BaseExpression(), "Changes"))))
-                    .WithSemicolonToken(Semicolon()));
+            if (cl.Properties.Count > 0)
+                client = client
+                    .AddMembers(DeclareField(changedFieldsTypeName, changedFieldsName));
+            
             
             if (!cl.CustomCtor)
             {
@@ -105,7 +88,7 @@ namespace Avalonia.SourceGenerator.CompositionGenerator
                     .AddModifiers(SyntaxKind.InternalKeyword, SyntaxKind.NewKeyword)
                     .AddAccessorListAccessors(AccessorDeclaration(SyntaxKind.GetAccessorDeclaration)
                         .WithSemicolonToken(Semicolon())));
-                client = client.AddMembers(
+            client = client.AddMembers(
                     ConstructorDeclaration(cl.Name)
                         .AddModifiers(SyntaxKind.InternalKeyword)
                         .WithParameterList(ParameterList(SeparatedList(new[]
@@ -141,20 +124,20 @@ namespace Avalonia.SourceGenerator.CompositionGenerator
                             ArgumentList(SeparatedList(new[]
                             {
                                 Argument(IdentifierName("compositor")),
-                            })))).WithBody(Block()));
+                            })))).WithBody(Block(ParseStatement("Initialize();"))));
             }
 
+            server = server.AddMembers(
+                MethodDeclaration(ParseTypeName("void"), "Initialize")
+                    .AddModifiers(SyntaxKind.PartialKeyword).WithSemicolonToken(Semicolon()));
+
 
             var changesVarName = "c";
             var changesVar = IdentifierName(changesVarName);
 
             server = server.AddMembers(
-                MethodDeclaration(ParseTypeName("void"), "ApplyChangesExtra")
-                    .AddParameterListParameters(Parameter(Identifier("c")).WithType(ParseTypeName(changesName)))
-                    .AddModifiers(SyntaxKind.PartialKeyword).WithSemicolonToken(Semicolon()));
-            
-            transport = transport.AddMembers(
-                MethodDeclaration(ParseTypeName("void"), "ResetExtra")
+                MethodDeclaration(ParseTypeName("void"), "DeserializeChangesExtra")
+                    .AddParameterListParameters(Parameter(Identifier("c")).WithType(ParseTypeName("BatchStreamReader")))
                     .AddModifiers(SyntaxKind.PartialKeyword).WithSemicolonToken(Semicolon()));
 
             var applyMethodBody = Block(
@@ -168,7 +151,7 @@ namespace Avalonia.SourceGenerator.CompositionGenerator
                 ExpressionStatement(InvocationExpression(IdentifierName("ApplyChangesExtra"))
                     .AddArgumentListArguments(Argument(IdentifierName("c"))))
             );
-            
+
             var uninitializedObjectName = "dummy";
             var serverStaticCtorBody = cl.Abstract
                 ? Block()
@@ -179,72 +162,51 @@ namespace Avalonia.SourceGenerator.CompositionGenerator
                     ParseStatement("InitializeFieldOffsets(dummy);")
                 );
 
-            var initializeFieldOffsetsBody = cl.ServerBase == null
+            var initializeFieldOffsetsBody = cl.Inherits == null
                 ? Block()
-                : Block(ParseStatement($"{cl.ServerBase}.InitializeFieldOffsets(dummy);"));
+                : Block(ParseStatement($"Server{cl.Inherits}.InitializeFieldOffsets(dummy);"));
 
             var resetBody = Block();
             var startAnimationBody = Block();
-            var getPropertyBody = Block();
             var serverGetPropertyBody = Block();
             var serverGetFieldOffsetBody = Block();
             var activatedBody = Block(ParseStatement("base.Activated();"));
             var deactivatedBody = Block(ParseStatement("base.Deactivated();"));
+            var serializeMethodBody = SerializeChangesPrologue(cl);
+            var deserializeMethodBody = DeserializeChangesPrologue(cl);
 
-            var defaultsMethodBody = Block();
+            var defaultsMethodBody = Block(ParseStatement("InitializeDefaultsExtra();"));
             
             foreach (var prop in cl.Properties)
             {
-                var fieldName = "_" + prop.Name.WithLowerFirst();
-                var fieldOffsetName = "s_OffsetOf" + fieldName;
+                var fieldName = PropertyBackingFieldName(prop);
+                var animatedFieldName = PropertyPendingAnimationFieldName(prop);
+                var fieldOffsetName = ServerPropertyOffsetFieldName(prop);
                 var propType = ParseTypeName(prop.Type);
                 var filteredPropertyType = prop.Type.TrimEnd('?');
                 var isObject = _objects.Contains(filteredPropertyType);
                 var isNullable = prop.Type.EndsWith("?");
-                
-
-
-
-                client = client
-                    .AddMembers(DeclareField(prop.Type, fieldName))
-                    .AddMembers(PropertyDeclaration(propType, prop.Name)
-                        .AddModifiers(SyntaxKind.PublicKeyword)
-                        .AddAccessorListAccessors(
-                            AccessorDeclaration(SyntaxKind.GetAccessorDeclaration,
-                                Block(ReturnStatement(IdentifierName(fieldName)))),
-                            AccessorDeclaration(SyntaxKind.SetAccessorDeclaration,
-                                Block(
-                                    ParseStatement("var changed = false;"),
-                                    IfStatement(BinaryExpression(SyntaxKind.NotEqualsExpression,
-                                            IdentifierName(fieldName),
-                                            IdentifierName("value")),
-                                        Block(
-                                            ParseStatement("On" + prop.Name + "Changing();"),
-                                            ParseStatement("changed = true;"),
-                                            GeneratePropertySetterAssignment(prop, fieldName, isObject, isNullable))
-                                    ),
-                                    ExpressionStatement(AssignmentExpression(SyntaxKind.SimpleAssignmentExpression,
-                                        IdentifierName(fieldName), IdentifierName("value"))),
-                                    ParseStatement($"if(changed) On" + prop.Name + "Changed();")
-                                ))
-                        ))
-                    .AddMembers(MethodDeclaration(ParseTypeName("void"), "On" + prop.Name + "Changed")
-                        .AddModifiers(SyntaxKind.PartialKeyword).WithSemicolonToken(Semicolon()))
-                    .AddMembers(MethodDeclaration(ParseTypeName("void"), "On" + prop.Name + "Changing")
-                        .AddModifiers(SyntaxKind.PartialKeyword).WithSemicolonToken(Semicolon()));
+                bool isPassthrough = false;
 
+                if (prop.Animated)
+                    client = client.AddMembers(DeclareField("IAnimationInstance?", animatedFieldName));
+                client = GenerateClientProperty(client, cl, prop, propType, isObject, isNullable);
 
                 var animatedServer = prop.Animated;
                 
                 var serverPropertyType = ((isObject ? "Server" : "") + prop.Type);
-                if (_manuals.TryGetValue(filteredPropertyType, out var manual) && manual.ServerName != null)
-                    serverPropertyType = manual.ServerName + (isNullable ? "?" : "");
-                
-
-                transport = transport
-                    .AddMembers(DeclareField((animatedServer ? "Animated" : "") + "Change<" + serverPropertyType + ">",
-                        prop.Name, SyntaxKind.PublicKeyword));
+                if (_manuals.TryGetValue(filteredPropertyType, out var manual))
+                {
+                    if (manual.Passthrough)
+                    {
+                        isPassthrough = true;
+                        serverPropertyType = prop.Type;
+                    }
 
+                    if (manual.ServerName != null)
+                        serverPropertyType = manual.ServerName + (isNullable ? "?" : "");
+                }
+                
                 if (animatedServer)
                     server = server.AddMembers(
                         DeclareField("ServerAnimatedValueStore<" + serverPropertyType + ">", fieldName),
@@ -301,7 +263,7 @@ namespace Avalonia.SourceGenerator.CompositionGenerator
                                     ArgumentList(SeparatedList(new[]
                                     {
                                         Argument(IdentifierName("this")),
-                                        Argument(changesVar),
+                                        Argument(ParseExpression("c.Batch.CommitedAt")),
                                         Argument(MemberAccess(changesVar, prop.Name, "Animation")),
                                         Argument(IdentifierName(fieldOffsetName))
                                     })))))
@@ -316,16 +278,18 @@ namespace Avalonia.SourceGenerator.CompositionGenerator
 
                 resetBody = resetBody.AddStatements(
                     ExpressionStatement(InvocationExpression(MemberAccess(prop.Name, "Reset"))));
-
+                
+                serializeMethodBody = ApplySerializeField(serializeMethodBody,cl, prop, isObject, isPassthrough);
+                deserializeMethodBody = ApplyDeserializeField(deserializeMethodBody,cl, prop, serverPropertyType, isObject);
+                
                 if (animatedServer)
                 {
-                    startAnimationBody = ApplyStartAnimation(startAnimationBody, prop, fieldName);
+                    startAnimationBody = ApplyStartAnimation(startAnimationBody, cl, prop);
                     activatedBody = activatedBody.AddStatements(ParseStatement($"{fieldName}.Activate(this);"));
                     deactivatedBody = deactivatedBody.AddStatements(ParseStatement($"{fieldName}.Deactivate(this);"));
                 }
 
-
-                getPropertyBody = ApplyGetProperty(getPropertyBody, prop);
+                
                 serverGetPropertyBody = ApplyGetProperty(serverGetPropertyBody, prop);
                 serverGetFieldOffsetBody = ApplyGetProperty(serverGetFieldOffsetBody, prop, fieldOffsetName);
 
@@ -345,55 +309,6 @@ namespace Avalonia.SourceGenerator.CompositionGenerator
                 }
             }
 
-            if (cl is GBrush brush && !cl.Abstract)
-            {
-                var brushName = brush.Name.StripPrefix("Composition");
-                /*
-                server = server.AddMembers(
-                    MethodDeclaration(ParseTypeName("ICbBrush"), "CreateBackendBrush")
-                        .AddModifiers(SyntaxKind.ProtectedKeyword, SyntaxKind.OverrideKeyword)
-                        .WithExpressionBody(ArrowExpressionClause(
-                            InvocationExpression(MemberAccess("Compositor", "Backend", "Create" + brushName))
-                        )).WithSemicolonToken(Semicolon())
-                );
-                if (!brush.CustomUpdate)
-                    server = server.AddMembers(
-                        MethodDeclaration(ParseTypeName("void"), "UpdateBackendBrush")
-                            .AddModifiers(SyntaxKind.ProtectedKeyword, SyntaxKind.OverrideKeyword)
-                            .AddParameterListParameters(Parameter(Identifier("brush"))
-                                .WithType(ParseTypeName("ICbBrush")))
-                            .AddBodyStatements(
-                                ExpressionStatement(
-                                    InvocationExpression(
-                                        MemberAccess(
-                                            ParenthesizedExpression(
-                                            CastExpression(ParseTypeName("ICb" + brushName), IdentifierName("brush"))), "Update"),
-                                        ArgumentList(SeparatedList(cl.Properties.Select(x =>
-                                        {
-                                            if(x.Type.TrimEnd('?') == "ICompositionSurface")
-                                                return Argument(
-                                                    ConditionalAccessExpression(IdentifierName(x.Name),
-                                                        MemberBindingExpression(IdentifierName("BackendSurface")))
-                                                );
-                                            if (_brushes.Contains(x.Type))
-                                                return Argument(
-                                                    ConditionalAccessExpression(IdentifierName(x.Name),
-                                                        MemberBindingExpression(IdentifierName("Brush")))
-                                                );
-                                            return Argument(IdentifierName(x.Name));
-                                        }))))
-                                )));
-
-*/
-            }
-            
-            server = server.AddMembers(
-                MethodDeclaration(ParseTypeName("void"), "ApplyCore")
-                    .AddModifiers(SyntaxKind.ProtectedKeyword, SyntaxKind.OverrideKeyword)
-                    .AddParameterListParameters(
-                        Parameter(Identifier("changes")).WithType(ParseTypeName("ChangeSet")))
-                    .WithBody(applyMethodBody));
-
             server = server.AddMembers(ConstructorDeclaration(serverName)
                 .WithModifiers(TokenList(Token(SyntaxKind.StaticKeyword)))
                 .WithBody(serverStaticCtorBody));
@@ -408,26 +323,32 @@ namespace Avalonia.SourceGenerator.CompositionGenerator
                     $"protected override void Activated(){{}}")!).WithBody(activatedBody))
                 .AddMembers(((MethodDeclarationSyntax)ParseMemberDeclaration(
                     $"protected override void Deactivated(){{}}")!).WithBody(deactivatedBody));
+            if (cl.Properties.Count > 0)
+                server = server.AddMembers(((MethodDeclarationSyntax)ParseMemberDeclaration(
+                            $"protected override void DeserializeChangesCore(BatchStreamReader reader, TimeSpan commitedAt){{}}")
+                        !)
+                    .WithBody(deserializeMethodBody));
 
             client = client.AddMembers(
-                MethodDeclaration(ParseTypeName("void"), "InitializeDefaults").WithBody(defaultsMethodBody));
-
-            transport = transport.AddMembers(MethodDeclaration(ParseTypeName("void"), "Reset")
-                .AddModifiers(SyntaxKind.PublicKeyword, SyntaxKind.OverrideKeyword)
-                .WithBody(resetBody.AddStatements(
-                    ExpressionStatement(InvocationExpression(IdentifierName("ResetExtra"))),
-                    ExpressionStatement(InvocationExpression(MemberAccess("base", "Reset"))))));
-
+                    MethodDeclaration(ParseTypeName("void"), "InitializeDefaults").WithBody(defaultsMethodBody))
+                .AddMembers(
+                    MethodDeclaration(ParseTypeName("void"), "InitializeDefaultsExtra")
+                        .AddModifiers(SyntaxKind.PartialKeyword).WithSemicolonToken(Semicolon()));
+            
+            if (cl.Properties.Count > 0)
+                client = client.AddMembers(((MethodDeclarationSyntax)ParseMemberDeclaration(
+                        $"private protected override void SerializeChangesCore(BatchStreamWriter writer){{}}")!)
+                    .WithBody(serializeMethodBody));
+            
             if (list != null)
                 client = AppendListProxy(list, client);
 
             if (startAnimationBody.Statements.Count != 0)
                 client = WithStartAnimation(client, startAnimationBody);
-
-            client = WithGetProperty(client, getPropertyBody, false);
-            server = WithGetProperty(server, serverGetPropertyBody, true);
+            
+            server = WithGetPropertyForAnimation(server, serverGetPropertyBody);
             server = WithGetFieldOffset(server, serverGetFieldOffsetBody);
-
+            
             if(cl.Implements.Count > 0)
                 foreach (var impl in cl.Implements)
                 {
@@ -441,57 +362,121 @@ namespace Avalonia.SourceGenerator.CompositionGenerator
                 }
 
 
+            SaveTo(unit.AddMembers(GenerateChangedFieldsEnum(cl)), "Transport",
+                ChangedFieldsTypeName(cl) + ".generated.cs");
+            
             SaveTo(unit.AddMembers(clientNs.AddMembers(client)),
                 cl.Name + ".generated.cs");
             SaveTo(unit.AddMembers(serverNs.AddMembers(server)),
                 "Server", "Server" + cl.Name + ".generated.cs");
-            SaveTo(unit.AddMembers(transportNs.AddMembers(transport)),
-                "Transport",  cl.Name + "Changes.generated.cs");
+        }
+        
+        private ClassDeclarationSyntax GenerateClientProperty(ClassDeclarationSyntax client, GClass cl, GProperty prop,
+            TypeSyntax propType, bool isObject, bool isNullable)
+        {
+            var fieldName = PropertyBackingFieldName(prop);
+            return client
+                    .AddMembers(DeclareField(prop.Type, fieldName))
+                    .AddMembers(PropertyDeclaration(propType, prop.Name)
+                        .AddModifiers(SyntaxKind.PublicKeyword)
+                        .AddAccessorListAccessors(
+                            AccessorDeclaration(SyntaxKind.GetAccessorDeclaration,
+                                Block(ReturnStatement(IdentifierName(fieldName)))),
+                            AccessorDeclaration(SyntaxKind.SetAccessorDeclaration,
+                                Block(
+                                    ParseStatement("var changed = false;"),
+                                    IfStatement(BinaryExpression(SyntaxKind.NotEqualsExpression,
+                                            IdentifierName(fieldName),
+                                            IdentifierName("value")),
+                                        Block(
+                                            ParseStatement("On" + prop.Name + "Changing();"),
+                                            ParseStatement("changed = true;"),
+                                            GeneratePropertySetterAssignment(cl, prop, isObject, isNullable))
+                                    ),
+                                    ExpressionStatement(AssignmentExpression(SyntaxKind.SimpleAssignmentExpression,
+                                        IdentifierName(fieldName), IdentifierName("value"))),
+                                    ParseStatement($"if(changed) On" + prop.Name + "Changed();")
+                                )).WithModifiers(TokenList(prop.InternalSet ? new[]{Token(SyntaxKind.InternalKeyword)} : Array.Empty<SyntaxToken>()))
+                        ))
+                    .AddMembers(MethodDeclaration(ParseTypeName("void"), "On" + prop.Name + "Changed")
+                        .AddModifiers(SyntaxKind.PartialKeyword).WithSemicolonToken(Semicolon()))
+                    .AddMembers(MethodDeclaration(ParseTypeName("void"), "On" + prop.Name + "Changing")
+                        .AddModifiers(SyntaxKind.PartialKeyword).WithSemicolonToken(Semicolon()));
         }
 
-        StatementSyntax GeneratePropertySetterAssignment(GProperty prop, string fieldName, bool isObject, bool isNullable)
+        EnumDeclarationSyntax GenerateChangedFieldsEnum(GClass cl)
         {
-            var normalChangesAssignment = (StatementSyntax)ExpressionStatement(AssignmentExpression(
-                SyntaxKind.SimpleAssignmentExpression,
-                MemberAccess((ExpressionSyntax) IdentifierName("Changes"), prop.Name,
-                    "Value"),
-                isObject
-                    ?  
-                    ConditionalMemberAccess(IdentifierName("value"), "Server", isNullable)
-                    : IdentifierName("value")));
-            if (!prop.Animated)
-                return normalChangesAssignment;
+            var changedFieldsEnum = EnumDeclaration(Identifier(ChangedFieldsTypeName(cl)));
+            int count = 0;
 
-            var code = $@"
-{{
-    if(animation is CompositionAnimation a)
-        Changes.{prop.Name}.Animation = a.CreateInstance(this.Server, value);
-    else
+            void AddValue(string name)
+            {
+                var value = 1ul << count; 
+                changedFieldsEnum = changedFieldsEnum.AddMembers(
+                    EnumMemberDeclaration(name)
+                        .WithEqualsValue(EqualsValueClause(ParseExpression(value.ToString()))));
+                count++;
+            }
+
+            foreach (var prop in cl.Properties)
+            {
+                AddValue(prop.Name);
+
+                if (prop.Animated) 
+                    AddValue(prop.Name + "Animated");
+            }
+
+            var baseType = count <= 8 ? "byte" : count <= 16 ? "ushort" : count <= 32 ? "uint" : "ulong";
+            return changedFieldsEnum.AddBaseListTypes(SimpleBaseType(ParseTypeName(baseType)))
+                .AddAttributeLists(AttributeList(SingletonSeparatedList(Attribute(IdentifierName("System.Flags")))));
+        }
+
+        StatementSyntax GeneratePropertySetterAssignment(GClass cl, GProperty prop, bool isObject, bool isNullable)
+        {
+            var pendingAnimationField = PropertyPendingAnimationFieldName(prop);
+
+            var code = @$"
+    // Update the backing value
+    {PropertyBackingFieldName(prop)} = value;
+    
+    // Register object for serialization in the next batch
+    {ChangedFieldsFieldName(cl)} |= {ChangedFieldsTypeName(cl)}.{prop.Name};
+    RegisterForSerialization();
+";
+            if (prop.Animated)
+            {
+                code += @$"
+    // Reset previous animation if any
+    {pendingAnimationField} = null;
+    {ChangedFieldsFieldName(cl)} &= ~{ChangedFieldsTypeName(cl)}.{prop.Name}Animated;
+    // Check for implicit animations
+    if(ImplicitAnimations != null && ImplicitAnimations.TryGetValue(""{prop.Name}"", out var animation) == true)
     {{
-        var saved = Changes.{prop.Name};
-        if(!StartAnimationGroup(animation, ""{prop.Name}"", value))
-            Changes.{prop.Name}.Value = value;
+        // Animation affects only current property
+        if(animation is CompositionAnimation a)
+        {{
+            {ChangedFieldsFieldName(cl)} |= {ChangedFieldsTypeName(cl)}.{prop.Name}Animated;
+            {pendingAnimationField} = a.CreateInstance(this.Server, value);
+        }}  
+        // Animation is triggered by the current field, but does not necessary affects it
+        StartAnimationGroup(animation, ""{prop.Name}"", value);
     }}
-}}
-
 ";
-            
-            return IfStatement(
-                ParseExpression(
-                    $"ImplicitAnimations != null && ImplicitAnimations.TryGetValue(\"{prop.Name}\", out var animation) == true"),
-                ParseStatement(code),
-                ElseClause(normalChangesAssignment)
-            );
+            }
+
+            return ParseStatement("{\n" + code + "\n}");
         }
         
-        BlockSyntax ApplyStartAnimation(BlockSyntax body, GProperty prop, string fieldName)
+        BlockSyntax ApplyStartAnimation(BlockSyntax body, GClass cl, GProperty prop)
         {
             var code = $@"
 if (propertyName == ""{prop.Name}"")
 {{
-var current = {fieldName};
+var current = {PropertyBackingFieldName(prop)};
 var server = animation.CreateInstance(this.Server, finalValue);
-Changes.{prop.Name}.Animation = server;
+{PropertyPendingAnimationFieldName(prop)} = server;
+{ChangedFieldsFieldName(cl)} |= {ChangedFieldsTypeName(cl)}.{prop.Name}Animated;
+RegisterForSerialization();
 return;
 }}
 ";
@@ -522,15 +507,75 @@ return;
 
             return body;
         }
+        
+        private BlockSyntax SerializeChangesPrologue(GClass cl)
+        {
+            return Block(
+                ParseStatement("base.SerializeChangesCore(writer);"),
+                ParseStatement($"writer.Write({ChangedFieldsFieldName(cl)});")
+                );
+        }
+        
+        BlockSyntax ApplySerializeField(BlockSyntax body, GClass cl, GProperty prop, bool isObject, bool isPassthrough)
+        {
+            var changedFields = ChangedFieldsFieldName(cl);
+            var changedFieldsType = ChangedFieldsTypeName(cl);
+            
+            var code = "";
+            if (prop.Animated)
+            {
+                code = $@"
+    if(({changedFields} & {changedFieldsType}.{prop.Name}Animated) == {changedFieldsType}.{prop.Name}Animated)
+        writer.WriteObject({PropertyPendingAnimationFieldName(prop)});
+    else ";
+            }
+
+            code += $@"
+    if(({changedFields} & {changedFieldsType}.{prop.Name}) == {changedFieldsType}.{prop.Name})
+        writer.Write{(isObject ? "Object" : "")}({PropertyBackingFieldName(prop)}{(isObject && !isPassthrough ? "?.Server!":"")});
+";
+            return body.AddStatements(ParseStatement(code));
+        }     
+        
+        private BlockSyntax DeserializeChangesPrologue(GClass cl)
+        {
+            return Block(ParseStatement($@"
+base.DeserializeChangesCore(reader, commitedAt);
+DeserializeChangesExtra(reader);
+var changed = reader.Read<{ChangedFieldsTypeName(cl)}>();
+"));
+        }
+        
+        BlockSyntax ApplyDeserializeField(BlockSyntax body, GClass cl, GProperty prop, string serverType, bool isObject)
+        {
+            var changedFieldsType = ChangedFieldsTypeName(cl);
+            var code = "";
+            if (prop.Animated)
+            {
+                code = $@"
+    if((changed & {changedFieldsType}.{prop.Name}Animated) == {changedFieldsType}.{prop.Name}Animated)
+            {PropertyBackingFieldName(prop)}.SetAnimation(this, commitedAt, reader.ReadObject<IAnimationInstance>(), {ServerPropertyOffsetFieldName(prop)});
+    else ";
+            }
+
+            var readValueCode = $"reader.Read{(isObject ? "Object" : "")}<{serverType}>()";
+            code += $@"
+    if((changed & {changedFieldsType}.{prop.Name}) == {changedFieldsType}.{prop.Name})
+";
+            if (prop.Animated)
+                code += $"{PropertyBackingFieldName(prop)}.SetValue(this, {readValueCode});";
+            else code += $"{prop.Name} =  {readValueCode};";
+            return body.AddStatements(ParseStatement(code));
+        }
 
-        ClassDeclarationSyntax WithGetProperty(ClassDeclarationSyntax cl, BlockSyntax body, bool server)
+        ClassDeclarationSyntax WithGetPropertyForAnimation(ClassDeclarationSyntax cl, BlockSyntax body)
         {
             if (body.Statements.Count == 0)
                 return cl;
             body = body.AddStatements(
                 ParseStatement("return base.GetPropertyForAnimation(name);"));
             var method = ((MethodDeclarationSyntax) ParseMemberDeclaration(
-                    $"{(server ? "public" : "internal")} override Avalonia.Rendering.Composition.Expressions.ExpressionVariant GetPropertyForAnimation(string name){{}}"))
+                    $"public override Avalonia.Rendering.Composition.Expressions.ExpressionVariant GetPropertyForAnimation(string name){{}}"))
                 .WithBody(body);
 
             return cl.AddMembers(method);

src/Avalonia.X11/X11Platform.cs

@@ -104,7 +104,7 @@ namespace Avalonia.X11
             }
 
             if (options.UseCompositor)
-                Compositor = Compositor.Create(AvaloniaLocator.Current.GetService<IRenderLoop>()!);
+                Compositor = new Compositor(AvaloniaLocator.Current.GetService<IRenderLoop>()!);
 
         }
 

src/Windows/Avalonia.Win32/Win32Platform.cs

@@ -188,7 +188,7 @@ namespace Avalonia.Win32
                 AvaloniaLocator.CurrentMutable.Bind<IPlatformDragSource>().ToSingleton<DragSource>();
             
             if (Options.UseCompositor)
-                Compositor = Compositor.Create(AvaloniaLocator.Current.GetRequiredService<IRenderLoop>());
+                Compositor = new Compositor(AvaloniaLocator.Current.GetRequiredService<IRenderLoop>());
         }
 
         public bool HasMessages()

tests/Avalonia.Base.UnitTests/Composition/BatchStreamTests.cs

@@ -0,0 +1,45 @@
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks.Dataflow;
+using Avalonia.Rendering.Composition.Transport;
+using Xunit;
+
+namespace Avalonia.Base.UnitTests.Composition;
+
+public class BatchStreamTests
+{
+    [Fact]
+    public void BatchStreamCorrectlyWritesAndReadsData()
+    {
+        var data = new BatchStreamData();
+        var memPool = new BatchStreamMemoryPool(100, _ => { });
+        var objPool = new BatchStreamObjectPool<object>(10, _ => { });
+
+        var guids = new List<Guid>();
+        var objects = new List<object>();
+        for (var c = 0; c < 453; c++)
+        {
+            guids.Add(Guid.NewGuid());
+            objects.Add(new object());
+        }
+
+        using (var writer = new BatchStreamWriter(data, memPool, objPool))
+        {
+            foreach(var guid in guids)
+                writer.Write(guid);
+            foreach (var obj in objects)
+                writer.WriteObject(obj);
+        }
+
+        using (var reader = new BatchStreamReader(data, memPool, objPool))
+        {
+            foreach (var guid in guids) 
+                Assert.Equal(guid, reader.Read<Guid>());
+            foreach (var obj in objects)
+                Assert.Equal(obj, reader.ReadObject());
+        }
+        
+
+
+    }
+}