From c9685e9155a742a437140f41ae353fb5d4a14d94 Mon Sep 17 00:00:00 2001
From: Trice Helix <81759026+TriceHelix@users.noreply.github.com>
Date: Sun, 12 Mar 2023 20:31:00 +0100
Subject: [PATCH] Fix NullReferenceException

- Initialized "culledNodes" field to avoid rare NullReferenceException on line 440
- Slight performance boost using cached HashSets instead of allocating new lists DrawNodes() call, also O(1) lookup time for graphs with many selected/culled nodes
---
 Scripts/Editor/NodeEditorGUI.cs | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/Scripts/Editor/NodeEditorGUI.cs b/Scripts/Editor/NodeEditorGUI.cs
index 35b2e2a..8f3a574 100755
--- a/Scripts/Editor/NodeEditorGUI.cs
+++ b/Scripts/Editor/NodeEditorGUI.cs
@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using UnityEditor;
@@ -12,8 +12,8 @@ namespace XNodeEditor {
     /// <summary> Contains GUI methods </summary>
     public partial class NodeEditorWindow {
         public NodeGraphEditor graphEditor;
-        private List<UnityEngine.Object> selectionCache;
-        private List<XNode.Node> culledNodes;
+        private readonly HashSet<UnityEngine.Object> selectionCache = new();
+        private readonly HashSet<XNode.Node> culledNodes = new();
         /// <summary> 19 if docked, 22 if not </summary>
         private int topPadding { get { return isDocked() ? 19 : 22; } }
         /// <summary> Executed after all other window GUI. Useful if Zoom is ruining your day. Automatically resets after being run.</summary>
@@ -399,8 +399,13 @@ namespace XNodeEditor {
 
         private void DrawNodes() {
             Event e = Event.current;
+
             if (e.type == EventType.Layout) {
-                selectionCache = new List<UnityEngine.Object>(Selection.objects);
+                selectionCache.Clear();
+                var objs = Selection.objects;
+                selectionCache.EnsureCapacity(objs.Length);
+                foreach (var obj in objs)
+                    selectionCache.Add(obj);
             }
 
             System.Reflection.MethodInfo onValidate = null;
@@ -432,7 +437,7 @@ namespace XNodeEditor {
 
             List<XNode.NodePort> removeEntries = new List<XNode.NodePort>();
 
-            if (e.type == EventType.Layout) culledNodes = new List<XNode.Node>();
+            if (e.type == EventType.Layout) culledNodes.Clear();
             for (int n = 0; n < graph.nodes.Count; n++) {
                 // Skip null nodes. The user could be in the process of renaming scripts, so removing them at this point is not advisable.
                 if (graph.nodes[n] == null) continue;