Merge pull request #820 from anatawa12/workaround-unity-bug

chore: avoid `Array index (n) is out of bounds (size=m)` error

CHANGELOG-PRERELEASE.md

@@ -24,6 +24,7 @@ The format is based on [Keep a Changelog].
   - In addition, location of the unknown components are shown on the error report.
 - AvatarOptimizer didn't register modification to ObjectRegistry `#815`
 - Empty Armature trick broken `#819`
+- Added workaround for `Array index (n) is out of bounds (size=m)` error
 
 ### Security
 

CHANGELOG.md

@@ -22,6 +22,7 @@ The format is based on [Keep a Changelog].
 - Unknown component warning were shown multiple time for one type `#818`
   - In addition, location of the unknown components are shown on the error report.
 - Empty Armature trick broken `#819`
+- Added workaround for `Array index (n) is out of bounds (size=m)` error
 
 ### Security
 

Editor/Processors/MeshInfo2Holder.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using Anatawa12.AvatarOptimizer.Processors.SkinnedMeshes;
@@ -20,11 +21,38 @@ public void OnActivate(BuildContext context)
         public void OnDeactivate(BuildContext context)
         {
             Debug.Assert(Holder != null, nameof(Holder) + " != null");
-            Holder.SaveToMesh();
+            // avoid Array index (n) is out of bounds (size=m) error
+            // by assigning null to AnimatorController before changing blendShapes count
+            // and assigning back after changing blendShapes count.
+            // see https://github.com/anatawa12/AvatarOptimizer/issues/804
+            using (new EvacuateAnimatorController(context))
+            {
+                Holder.SaveToMesh();
+            }
             Holder = null;
         }
     }
 
+    internal struct EvacuateAnimatorController : IDisposable
+    {
+        private Dictionary<Animator, RuntimeAnimatorController> _controllers;
+
+        public EvacuateAnimatorController(BuildContext context)
+        {
+            _controllers = context.GetComponents<Animator>()
+                .ToDictionary(a => a, a => a.runtimeAnimatorController);
+
+            foreach (var animator in _controllers.Keys)
+                animator.runtimeAnimatorController = null;
+        }
+
+        public void Dispose()
+        {
+            foreach (var (animator, runtimeAnimatorController) in _controllers)
+                animator.runtimeAnimatorController = runtimeAnimatorController;
+        }
+    }
+
     internal class MeshInfo2Holder
     {
         private readonly Dictionary<SkinnedMeshRenderer, MeshInfo2> _skinnedCache =