Fix additional data editors with non editable objects

com.unity.render-pipelines.core/Editor/CoreEditorUtils.cs

@@ -797,6 +797,27 @@ public static T[] GetAdditionalData<T>(UnityEngine.Object[] targets, Action<T> i
             return data;
         }
 
+        /// <summary>Add the appropriate AdditionalData to the given GameObject and its children containing the original component</summary>
+        /// <typeparam name="T">The type of the original component</typeparam>
+        /// <typeparam name="AdditionalT">The type of the AdditionalData component</typeparam>
+        /// <param name="go">The root object to update</param>
+        /// <param name="initDefault">[Optional] The default value to use if there is no AdditionalData</param>
+        public static void AddAdditionalData<T, AdditionalT>(GameObject go, Action<AdditionalT> initDefault = null)
+            where T : Component
+            where AdditionalT : Component
+        {
+            var components = go.GetComponentsInChildren(typeof(T), true);
+            foreach (var c in components)
+            {
+                if (!c.TryGetComponent<AdditionalT>(out _))
+                {
+                    var hd = c.gameObject.AddComponent<AdditionalT>();
+                    if (initDefault != null)
+                        initDefault(hd);
+                }
+            }
+        }
+
         /// <summary>Create a game object</summary>
         /// <param name="parent">The parent</param>
         /// <param name="name">The wanted name (can be updated with a number if a sibling with same name exist</param>

com.unity.render-pipelines.high-definition/CHANGELOG.md

@@ -22,6 +22,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Fixed material keywords with fbx importer.
 - Fixed lightmaps not working properly with shader graphs in ray traced reflections (case 1305335).
 - Fixed skybox for ortho cameras.
+- Fixed model import by adding additional data if needed.
 
 ### Changed
 - Removed the material pass probe volumes evaluation mode.

com.unity.render-pipelines.high-definition/Editor/AssetProcessors/ModelPostProcessor.cs

@@ -0,0 +1,16 @@
+using UnityEngine;
+using UnityEngine.Rendering;
+using UnityEngine.Rendering.HighDefinition;
+
+namespace UnityEditor.Rendering.HighDefinition
+{
+    class ModelPostprocessor : AssetPostprocessor
+    {
+        void OnPostprocessModel(GameObject go)
+        {
+            CoreEditorUtils.AddAdditionalData<Camera, HDAdditionalCameraData>(go, HDAdditionalCameraData.InitDefaultHDAdditionalCameraData);
+            CoreEditorUtils.AddAdditionalData<Light, HDAdditionalLightData>(go, HDAdditionalLightData.InitDefaultHDAdditionalLightData);
+            CoreEditorUtils.AddAdditionalData<ReflectionProbe, HDAdditionalReflectionData>(go);
+        }
+    }
+}

com.unity.render-pipelines.universal/Editor/AssetPostProcessors/ModelPostProcessor.cs

@@ -0,0 +1,15 @@
+using UnityEngine;
+using UnityEngine.Rendering;
+using UnityEngine.Rendering.Universal;
+
+namespace UnityEditor.Rendering.Universal
+{
+    class ModelPostprocessor : AssetPostprocessor
+    {
+        void OnPostprocessModel(GameObject go)
+        {
+            CoreEditorUtils.AddAdditionalData<Camera, UniversalAdditionalCameraData>(go);
+            CoreEditorUtils.AddAdditionalData<Light, UniversalAdditionalLightData>(go);
+        }
+    }
+}