It’s hardly an inspector or stage problem. I see that when renaming/replacing FBX material in the standard piplane, everything happens as it should.
Video 
It looks like after:
fbx deletions
|| material reference violations
|| object installation
some links are broken and the scene does not receive a call to redraw, although the material was replaced in the prefab.
to test this, I used the following code:
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using UnityEditor;
using UnityEngine;
using Object = UnityEngine.Object;
namespace Code.Editor
{
public class FbxContainer: ScriptableObject
{
}
public class AssetImportPostprocessor : AssetPostprocessor
{
#region Importer
private void OnPreprocessModel()
{
ModelImporter modelImporter = assetImporter as ModelImporter;
modelImporter.importBlendShapes = false;
modelImporter.importCameras = false;
modelImporter.importVisibility = false;
modelImporter.importLights = false;
modelImporter.materialImportMode = ModelImporterMaterialImportMode.ImportStandard;
modelImporter.materialLocation = ModelImporterMaterialLocation.External;
modelImporter.materialName = ModelImporterMaterialName.BasedOnMaterialName;
modelImporter.materialSearch = ModelImporterMaterialSearch.Everywhere;
modelImporter.importTangents = ModelImporterTangents.CalculateMikk;
modelImporter.isReadable = false;
modelImporter.animationType = ModelImporterAnimationType.None;
modelImporter.importAnimation = false;
}
private static void OnPostprocessAllAssets(string[] importedAssets, string[] deletedAssets, string[] movedAssets,
string[] movedFromAssetPaths)
{
Debug.Log("Log");
foreach (var assetPath in importedAssets)
{
string ext = String.Empty;
ext = Path.GetExtension(assetPath);
switch (ext.ToLower())
{
case ".fbx":
CreateSimplePrefab(assetPath);
// ConvertMesh(assetPath);
break;
}
}
}
#endregion
#region Methods
public static void CreateSimplePrefab(string sourceAssetPath)
{
var sourceModel = AssetDatabase.LoadAssetAtPath<GameObject>(sourceAssetPath);
// get paths
var modelPath = sourceAssetPath.Substring(0, sourceAssetPath.LastIndexOf("/"));
var assetsRootPath = modelPath.Substring(0, modelPath.LastIndexOf("/"));
// simulate path
var pathVisualPrefabsFolder = assetsRootPath + "/Prefabs/VisualPrefabs";
var pathPrefabsFolder = assetsRootPath + "/Prefabs";
// VISUAL PREFAB
// recursively create folders
Directory.CreateDirectory(pathVisualPrefabsFolder);
var pathToSaveVisualPrefab = pathVisualPrefabsFolder + "/" + sourceModel.name + "_!VisualPrefab.prefab";
sourceModel.name += "_!Visual";
sourceModel.isStatic = true;
PrefabUtility.SaveAsPrefabAsset(sourceModel, pathToSaveVisualPrefab);
}
public static void ConvertMesh(string sourceAssetPath)
{
var sourceModel = AssetDatabase.LoadAssetAtPath<GameObject>(sourceAssetPath);
var sourceModelCopy = Object.Instantiate(sourceModel);
sourceModelCopy.name = sourceModelCopy.name.Replace("(Clone)", "");
var sourceMeshFilters = sourceModelCopy.GetComponentsInChildren<MeshFilter>();
var sourceSkinnedMeshRenderer = sourceModelCopy.GetComponentsInChildren<SkinnedMeshRenderer>();
var sourceAvatar = AssetDatabase.LoadAssetAtPath<Avatar>(sourceAssetPath);
// PRODUCE CONTAINER
string containerPath = GetFullPathWithoutExtension(sourceAssetPath) + ".asset";
FbxContainer container = AssetDatabase.LoadAssetAtPath<FbxContainer>(containerPath);
// if there is no container, create one and fill it
if (!container)
{
ScriptableObject containerObj = ScriptableObject.CreateInstance<FbxContainer>();
AssetDatabase.CreateAsset(containerObj, containerPath);
foreach (var smf in sourceMeshFilters)
{
var sourceSubAsset = smf.sharedMesh;
var artifactSubAsset = AttachSubAsset(sourceSubAsset, containerPath);
// assign a mesh to the source model meshFilter so that when the model is saved to the prefab, the link will already be thrown through
smf.sharedMesh = artifactSubAsset;
}
}
// if the container exists
else
{
var existingContainerSubAssets = AssetDatabase.LoadAllAssetRepresentationsAtPath(containerPath).OfType<Mesh>().ToList();
foreach (var smf in sourceMeshFilters)
{
var sourceSubAsset = smf.sharedMesh;
// check if a particular subAsset needs to be updated
var artifactSubAsset = UpdateSubAsset(existingContainerSubAssets, sourceSubAsset, containerPath);
smf.sharedMesh = artifactSubAsset;
}
// destroy because the Artist removed them in the original model
foreach (var subAsset in existingContainerSubAssets)
{
Object.DestroyImmediate(subAsset, true);
}
}
AssetDatabase.SaveAssets();
// PRODUCE PREFAB, VISUAL PREFAB, MECHANIC PREFABS
GameObject tempPrefab = null;
// get paths
var modelPath = sourceAssetPath.Substring(0, sourceAssetPath.LastIndexOf("/"));
var assetsRootPath = modelPath.Substring(0, modelPath.LastIndexOf("/"));
// simulate path
var pathVisualPrefabsFolder = assetsRootPath + "/Prefabs/VisualPrefabs";
var pathPrefabsFolder = assetsRootPath + "/Prefabs";
var pathToSaveVisualPrefab = pathVisualPrefabsFolder + "/" + sourceModelCopy.name + "_!VisualPrefab.prefab";
var pathToSaveMechanicPrefab = pathPrefabsFolder + "/" + sourceModelCopy.name + ".prefab";
// VISUAL PREFAB
// recursively create folders
Directory.CreateDirectory(pathVisualPrefabsFolder);
tempPrefab = StaticVisualPrefabCreate(sourceModelCopy, pathToSaveVisualPrefab);
// MECHANIC PREFAB
if (!AssetDatabase.AssetPathExists(pathToSaveMechanicPrefab))
{
if (tempPrefab)
{
StaticMechanicPrefabCreate(tempPrefab, pathToSaveMechanicPrefab);
}
}
Object.DestroyImmediate(sourceModelCopy, true);
DeleteAsset(sourceAssetPath);
}
private static Mesh AttachSubAsset(Mesh sourceSubAsset, string containerPath)
{
Mesh artifactSubAsset = Object.Instantiate(sourceSubAsset);
artifactSubAsset.name = sourceSubAsset.name + "_!Artifact";
AssetDatabase.AddObjectToAsset(artifactSubAsset, containerPath);
return artifactSubAsset;
}
private static Mesh UpdateSubAsset(List<Mesh> existingContainerSubAssets, Mesh sourceSubAsset, string containerPath)
{
// are there any subAssets that in theory need to be updated?
var artifactToUpdate = existingContainerSubAssets.Find(x => x.name.Equals(sourceSubAsset.name + "_!Artifact"));
if (artifactToUpdate)
{
Vector3[] normals = sourceSubAsset.normals;
sourceSubAsset.name += "_!Artifact";
EditorUtility.CopySerialized(sourceSubAsset, artifactToUpdate);
artifactToUpdate.normals = normals;
// all this recalculation crap doesn't seem to be necessary
// artifactToUpdate.RecalculateBounds();
// RecalculateNormals always leaves a UV seam trail
// artifactToUpdate.RecalculateNormals();
// artifactToUpdate.RecalculateTangents();
// remove from the list the subAssets that have been processed, the remaining subAssets in
// the list are candidates for destroy because the Artist removed them in the original model
existingContainerSubAssets.Remove(artifactToUpdate);
// assign a mesh to the source model meshFilter so that when the model is saved to the prefab, the link will already be thrown through
return artifactToUpdate;
}
// if a subAsset is present in the source model, but it is not present in the container subAssets,
// then this subAsset must be created and attached to the container
var artifactSubAsset = AttachSubAsset(sourceSubAsset, containerPath);
// assign a mesh to the source model meshFilter so that when the model is saved to the prefab, the link will already be thrown through
return artifactSubAsset;
}
private static GameObject StaticVisualPrefabCreate(GameObject sourceModel, string pathToSaveVisualPrefab)
{
sourceModel.name += "_!Visual";
sourceModel.isStatic = true;
var visualPrefab = PrefabUtility.SaveAsPrefabAsset(sourceModel, pathToSaveVisualPrefab);
return visualPrefab;
}
private static void StaticMechanicPrefabCreate(GameObject visualPrefab, string pathToSavePrefab)
{
GameObject rootObj = new GameObject();
GameObject visualRootObj = new GameObject();
visualRootObj.transform.parent = rootObj.transform;
visualRootObj.name = "Visual";
rootObj.name = visualPrefab.name.Replace("_!Visual", "");
GameObject visualPrefabInst = PrefabUtility.InstantiatePrefab(visualPrefab) as GameObject;
visualPrefabInst.transform.parent = visualRootObj.transform;
PrefabUtility.SaveAsPrefabAsset(rootObj, pathToSavePrefab);
Object.DestroyImmediate(visualPrefabInst);
Object.DestroyImmediate(rootObj);
AssetDatabase.SaveAssets();
}
#endregion
#region Helpers
private static String GetFullPathWithoutExtension(String path)
{
return Path.Combine(Path.GetDirectoryName(path), Path.GetFileNameWithoutExtension(path));
}
private static void DeleteAsset(string path)
{
AssetDatabase.DeleteAsset(path);
}
#endregion
}
}
