fix(rendering): reconcile shadow roots from live runtime

Recover ordinary live roots from LiveEntityRuntime's canonical active spatial workset instead of relying on already-retained derived records. Keep attached children callback-authoritative, cache immutable selection geometry fingerprints, and pin zero-allocation retained update paths with regression tests.

Release gate: 3,733 App tests / 3 skips; 8,217 complete-solution tests / 5 skips.

Co-Authored-By: OpenAI Codex <codex@openai.com>

src/AcDream.App/Rendering/Scene/CurrentRenderSceneOracle.cs

@@ -211,6 +211,8 @@ internal sealed class CurrentRenderSceneOracle :
             new(ReferenceEqualityComparer.Instance);
     private readonly List<CurrentRenderSelectionFingerprint>
         _selectionParts = [];
+    private readonly Dictionary<uint, SelectionGeometryCacheEntry>
+        _selectionGeometryByGfxObj = [];
     private ulong _frameSequence;
     private int _abortedFrames;
     private int _outdoorStaticCount;
@@ -637,16 +639,15 @@ internal sealed class CurrentRenderSceneOracle :
         }
         ArgumentNullException.ThrowIfNull(mesh);
 
-        StableRenderHash128 geometry = StableRenderHash128.Create();
-        geometry.Add(mesh.SphereCenter);
-        geometry.Add(mesh.SphereRadius);
-        geometry.Add(mesh.Polygons.Count);
-        foreach (RetailSelectionPolygon polygon in mesh.Polygons)
+        if (!_selectionGeometryByGfxObj.TryGetValue(
+                gfxObjId,
+                out SelectionGeometryCacheEntry cachedGeometry)
+            || !ReferenceEquals(cachedGeometry.Mesh, mesh))
         {
-            geometry.Add(polygon.SingleSided);
-            geometry.Add(polygon.Vertices.Count);
-            foreach (Vector3 vertex in polygon.Vertices)
-                geometry.Add(vertex);
+            cachedGeometry = new SelectionGeometryCacheEntry(
+                mesh,
+                FingerprintSelectionGeometry(mesh));
+            _selectionGeometryByGfxObj[gfxObjId] = cachedGeometry;
         }
 
         var fingerprint = new CurrentRenderSelectionFingerprint(
@@ -656,7 +657,7 @@ internal sealed class CurrentRenderSceneOracle :
             PartIndex: partIndex,
             GfxObjId: gfxObjId,
             LocalToWorld: localToWorld,
-            Geometry: geometry.Finish());
+            Geometry: cachedGeometry.Fingerprint);
         _selectionParts.Add(fingerprint);
         _selectionHash.Add(fingerprint.Sequence);
         _selectionHash.Add(fingerprint.ServerGuid);
@@ -722,8 +723,11 @@ internal sealed class CurrentRenderSceneOracle :
 
         StableRenderHash128 geometry = StableRenderHash128.Create();
         geometry.Add(entity.MeshRefs.Count);
-        foreach (MeshRef mesh in entity.MeshRefs)
+        for (int meshIndex = 0;
+             meshIndex < entity.MeshRefs.Count;
+             meshIndex++)
         {
+            MeshRef mesh = entity.MeshRefs[meshIndex];
             geometry.Add(mesh.GfxObjId);
             geometry.Add(mesh.PartTransform);
         }
@@ -734,8 +738,12 @@ internal sealed class CurrentRenderSceneOracle :
             appearance.Add(true);
             appearance.Add(palette.BasePaletteId);
             appearance.Add(palette.SubPalettes.Count);
-            foreach (PaletteOverride.SubPaletteRange range in palette.SubPalettes)
+            for (int rangeIndex = 0;
+                 rangeIndex < palette.SubPalettes.Count;
+                 rangeIndex++)
             {
+                PaletteOverride.SubPaletteRange range =
+                    palette.SubPalettes[rangeIndex];
                 appearance.Add(range.SubPaletteId);
                 appearance.Add(range.Offset);
                 appearance.Add(range.Length);
@@ -747,8 +755,11 @@ internal sealed class CurrentRenderSceneOracle :
         }
 
         appearance.Add(entity.PartOverrides.Count);
-        foreach (PartOverride part in entity.PartOverrides)
+        for (int partIndex = 0;
+             partIndex < entity.PartOverrides.Count;
+             partIndex++)
         {
+            PartOverride part = entity.PartOverrides[partIndex];
             appearance.Add(part.PartIndex);
             appearance.Add(part.GfxObjId);
         }
@@ -784,6 +795,31 @@ internal sealed class CurrentRenderSceneOracle :
             Appearance: appearance.Finish());
     }
 
+    private static RenderSceneHash128 FingerprintSelectionGeometry(
+        RetailSelectionMesh mesh)
+    {
+        StableRenderHash128 geometry = StableRenderHash128.Create();
+        geometry.Add(mesh.SphereCenter);
+        geometry.Add(mesh.SphereRadius);
+        geometry.Add(mesh.Polygons.Count);
+        for (int polygonIndex = 0;
+             polygonIndex < mesh.Polygons.Count;
+             polygonIndex++)
+        {
+            RetailSelectionPolygon polygon = mesh.Polygons[polygonIndex];
+            geometry.Add(polygon.SingleSided);
+            geometry.Add(polygon.Vertices.Count);
+            for (int vertexIndex = 0;
+                 vertexIndex < polygon.Vertices.Count;
+                 vertexIndex++)
+            {
+                geometry.Add(polygon.Vertices[vertexIndex]);
+            }
+        }
+
+        return geometry.Finish();
+    }
+
     private static InteriorEntityPartition.ProjectionClass ProjectionClassOf(
         WorldEntity entity) =>
         entity.ServerGuid != 0
@@ -792,6 +828,10 @@ internal sealed class CurrentRenderSceneOracle :
                 ? InteriorEntityPartition.ProjectionClass.CellStatic
                 : InteriorEntityPartition.ProjectionClass.OutdoorStatic;
 
+    private readonly record struct SelectionGeometryCacheEntry(
+        RetailSelectionMesh Mesh,
+        RenderSceneHash128 Fingerprint);
+
     private static void AddPViewCandidate(
         ref StableRenderHash128 hash,
         in CurrentRenderPViewCandidateFingerprint candidate)

src/AcDream.App/Rendering/Scene/LiveRenderProjectionJournal.cs

@@ -25,6 +25,7 @@ internal sealed class LiveRenderProjectionJournal : ILiveRenderProjectionSink
     private readonly LiveEntityRuntime _runtime;
     private readonly RenderProjectionJournal _journal;
     private readonly Dictionary<uint, TrackedProjection> _byLocalId = [];
+    private readonly List<LiveEntityRecord> _activeRootScratch = [];
     private readonly List<TrackedProjection> _activeScratch = [];
 
     public LiveRenderProjectionJournal(
@@ -107,10 +108,34 @@ internal sealed class LiveRenderProjectionJournal : ILiveRenderProjectionSink
     /// </summary>
     public void SynchronizeActiveSources()
     {
+        // The canonical live-runtime workset is the source of truth for world
+        // roots. Walking only this journal's already-tracked values would make
+        // a missed/reordered derived callback permanent and prevent shadow
+        // comparison from converging after a same-location revisit.
+        _runtime.CopySpatialRootObjectRecordsTo(_activeRootScratch);
+        for (int i = 0; i < _activeRootScratch.Count; i++)
+        {
+            LiveEntityRecord record = _activeRootScratch[i];
+            if (!record.ResourcesRegistered
+                || record.WorldEntity is not { } entity
+                || !_runtime.IsCurrentSpatialRootObject(record))
+            {
+                continue;
+            }
+
+            Upsert(record, entity, record.IsSpatiallyVisible);
+        }
+
+        // Attached children are not members of the ordinary root workset.
+        // Their exact EntityReady/pose/removal callbacks remain authoritative;
+        // synchronization only refreshes children whose attachment projection
+        // is still retained by this derived scene.
         _activeScratch.Clear();
         foreach (TrackedProjection tracked in _byLocalId.Values)
         {
-            if (tracked.Record.IsSpatiallyProjected)
+            if (tracked.Record.IsSpatiallyProjected
+                && tracked.Record.ProjectionKind is
+                    LiveEntityProjectionKind.Attached)
                 _activeScratch.Add(tracked);
         }
 
@@ -137,6 +162,7 @@ internal sealed class LiveRenderProjectionJournal : ILiveRenderProjectionSink
     public void ResetTracking()
     {
         _byLocalId.Clear();
+        _activeRootScratch.Clear();
         _activeScratch.Clear();
     }