[Fix] PropertyBinder : Reset & Undo (#212)

* Fix missing record object for proper undo/redo & reset

* *Update changelog.md

* Fix issue https://favro.com/organization/c564ede4ed3337f7b17986b6/1973edb4634ba00a90689144?card=Uni-160638

* Avoid VFXPropertyBinder to be added twice

* Fix incorrect reference after copy past

* Fix RemoveComponent clearing property binder first

* Handle Copy/Past \o/

* Let the LateUpdate without any editor code & use Update (avoid the one frame of latency for inspector)

* Remove useless recompute of GetComponents every frame, and use Reload (safer)

* Remove dead code

* *Add new entry in changelog (side improvement/fix)

* *Update comment

Author: PaulDemeulenaere

com.unity.visualeffectgraph/CHANGELOG.md

@@ -18,6 +18,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Move Assets/Create/Visual Effects/Visual Effect Subgraph Block to Assets/Create/VFX/VFX Subgraph Block
 - Allow remaking an existing link.
 - Sphere and Cube outputs are now experimental
+- Property Binder : Handle Remove Component removing linked hidden scriptable objectfields
+- Property Binder : Prevent multiple VFXPropertyBinder within the same game object
 
 ### Fixed
 - VFXEventBinderBase throwing a null reference exception in runtime
@@ -37,6 +39,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Sample Mesh Color when value is stored as float.
 - Compilation error due to direct access to GetWorldToObjectMatrix instead of VFXGetWorldToObjectMatrix [Case 1308481](https://issuetracker.unity3d.com/product/unity/issues/guid/1308481/)
 - Safe Normalization of Cross Products in Orient blocks [Case 1272724](https://issuetracker.unity3d.com/product/unity/issues/guid/1272724)
+- Property Binder : Undo after reset [Case 1293794](https://issuetracker.unity3d.com/product/unity/issues/guid/1293794/)
+- Property Binder : Allow copy/past from a game object to another
 
 ## [11.0.0] - 2020-10-21
 

com.unity.visualeffectgraph/Editor/Utilities/PropertyBinding/VFXPropertyBinderEditor.cs

@@ -14,6 +14,14 @@ namespace UnityEditor.Experimental.VFX.Utility
     [CustomEditor(typeof(VFXPropertyBinder))]
     class VFXPropertyBinderEditor : Editor
     {
+        [MenuItem("CONTEXT/VFXPropertyBinder/Remove Component", false, 5000)]
+        public static void RemoveComponent(MenuCommand command)
+        {
+            var propertyBinder = (VFXPropertyBinder)command.context;
+            propertyBinder.ClearPropertyBinders();
+            Undo.DestroyObjectImmediate(propertyBinder);
+        }
+
         ReorderableList m_List;
         SerializedProperty m_Elements;
         SerializedProperty m_Component;
@@ -246,7 +254,6 @@ public void RemoveElement(ReorderableList list)
             if (element != null)
             {
                 Undo.DestroyObjectImmediate(element);
-                m_Elements.DeleteArrayElementAtIndex(index); // Delete object reference
             }
             else
             {

com.unity.visualeffectgraph/Runtime/Utilities/PropertyBinding/VFXPropertyBinder.cs

@@ -11,6 +11,7 @@ namespace UnityEngine.VFX.Utility
     /// </summary>
     [RequireComponent(typeof(VisualEffect))]
     [DefaultExecutionOrder(1)]
+    [DisallowMultipleComponent]
     [ExecuteInEditMode]
     public class VFXPropertyBinder : MonoBehaviour
     {
@@ -33,28 +34,77 @@ public class VFXPropertyBinder : MonoBehaviour
 
         private void OnEnable()
         {
-            m_VisualEffect = GetComponent<VisualEffect>();
+            Reload();
+        }
+
+        private void OnValidate()
+        {
+            Reload();
         }
 
         static private void SafeDestroy(Object toDelete)
         {
+#if UNITY_EDITOR
             if (Application.isPlaying)
-                Destroy(toDelete);
+                Destroy(toDelete); //Undo.DestroyObjectImmediate is needed only for Reset, which can't be called in play mode
             else
-                DestroyImmediate(toDelete);
+                UnityEditor.Undo.DestroyObjectImmediate(toDelete);
+#else
+            Destroy(toDelete);
+#endif
         }
 
-        private void Reset()
+#if UNITY_EDITOR
+        List<VFXBinderBase> m_BinderToCopyPaste;
+#endif
+
+        private void Reload()
         {
             m_VisualEffect = GetComponent<VisualEffect>();
+#if UNITY_EDITOR
+            //Handle probable copy/paste component saving list of inappropriate entries.
+            m_BinderToCopyPaste = new List<VFXBinderBase>();
+            foreach (var bindings in m_Bindings)
+            {
+                if (bindings != null && bindings.gameObject != gameObject)
+                    m_BinderToCopyPaste.Add(bindings);
+            }
+            if (m_BinderToCopyPaste.Count == 0)
+                m_BinderToCopyPaste = null;
+#endif
             m_Bindings = new List<VFXBinderBase>();
             m_Bindings.AddRange(gameObject.GetComponents<VFXBinderBase>());
+        }
+
+        private void Reset()
+        {
+            Reload();
             ClearPropertyBinders();
         }
 
+#if UNITY_EDITOR
+        void Update()
+        {
+            if (m_BinderToCopyPaste != null)
+            {
+                //We can't add a component during a OnInvalidate, restore & copy linked binders (from copy/past) here
+                foreach (var copyPaste in m_BinderToCopyPaste)
+                {
+                    var type = copyPaste.GetType();
+                    var newComponent = gameObject.AddComponent(type);
+                    UnityEditor.EditorUtility.CopySerialized(copyPaste, newComponent);
+                }
+
+                m_BinderToCopyPaste = null;
+                Reload();
+            }
+        }
+
+#endif
         void LateUpdate()
         {
-            if (!m_ExecuteInEditor && Application.isEditor && !Application.isPlaying) return;
+            if (!m_ExecuteInEditor && Application.isEditor && !Application.isPlaying)
+                return;
 
             for (int i = 0; i < m_Bindings.Count; i++)
             {