fix: scene view selection outline is lost when pipeline rebuilds occur (

#461)

Closes: #446

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 
 ### Fixed
+- [#461] Selection outlines in scene view do not work reliably when preview system is active
 - [#459] "Proxy object was destroyed improperly! Resetting pipeline..." error appears frequently
 
 - [#460] Preview system fails to recover when the primary proxy is destroyed

Editor/PreviewSystem/Rendering/ProxySession.cs

@@ -4,6 +4,7 @@
 using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Linq;
+using System.Reflection;
 using nadena.dev.ndmf.preview.trace;
 using UnityEditor;
 using UnityEngine;
@@ -28,7 +29,19 @@ internal class ProxySession : IDisposable
             _active?.ProxyToOriginalObject ?? ImmutableDictionary<GameObject, GameObject>.Empty;
 
         internal ProxyObjectCache _proxyCache = new();
+        private static readonly FieldInfo _selectionCacheDirtyField;
 
+        static ProxySession()
+        {
+            _selectionCacheDirtyField = typeof(SceneView)
+                .GetField("s_SelectionCacheDirty", BindingFlags.NonPublic | BindingFlags.Static);
+        }
+
+        private void ClearSelectionCache()
+        {
+            _selectionCacheDirtyField.SetValue(null, true);
+        }
+
         private ImmutableList<IRenderFilter> _filters;
         public ImmutableList<IRenderFilter> Filters
         {
@@ -104,6 +117,7 @@ public void Dispose()
                     _active?.Dispose();
                     _active = _next;
                     _next = null;
+                    ClearSelectionCache();
                 }
 
                 if (activeIsReady)