Base Work for asset dependency window

Editor/AssetDependencyWindow.meta

+fileFormatVersion: 2
+guid: 99bef5955dc48db419f13a8092e4f5a9
+folderAsset: yes
+DefaultImporter:
+  externalObjects: {}
+  userData: 
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Editor/AssetDependencyWindow/AssetDependencyWindow.cs

+using UnityEngine;
+using UnityEditor;
+using System.Collections.Generic;
+using System.Linq;
+using UnityEditor.IMGUI.Controls;
+
+public class AssetDependencyWindow : EditorWindow
+{
+    public static AssetDependencyWindow instance { get => s_Instance; }
+    static AssetDependencyWindow s_Instance;
+
+    static bool includeMonoScript = false;
+    static bool includeSubAssets = false;
+
+    [MenuItem("Assets/Show Asset Dependencies... #F4", validate = true)]
+    static bool CanOpen()
+    {
+        return Selection.activeObject != null;
+    }
+
+    [MenuItem("Assets/Show Asset Dependencies... #F4")]
+    static void Open()
+    {
+        if (s_Instance == null)
+            s_Instance = GetWindow<AssetDependencyWindow>();
+        else
+            s_Instance.Focus();
+
+        if(Selection.objects.Length > 0)
+        {
+            foreach(var obj  in Selection.objects)
+            {
+                s_Instance.WatchAsset(obj);
+            }
+
+            s_Instance.dtv.Reload();
+        }
+    }
+
+    static List<Object> watched;
+
+    void WatchAsset(Object obj)
+    {
+        if (watched == null)
+            watched = new List<Object>();
+
+        if (!watched.Contains(obj))
+            watched.Add(obj);
+    }
+
+    private void OnEnable()
+    {
+        var title = EditorGUIUtility.IconContent("Project");
+        title.text = "Asset Dependencies";
+        titleContent = new GUIContent(title);
+    }
+
+    private void OnSelectionChange()
+    {
+        Repaint();
+    }
+
+    DependencyTreeView dtv;
+
+    private void OnGUI()
+    {
+        using(new GUILayout.HorizontalScope(EditorStyles.toolbar))
+        {
+            EditorGUI.BeginChangeCheck();
+            includeMonoScript = GUILayout.Toggle(includeMonoScript, "MonoScript", EditorStyles.toolbarButton);
+            includeSubAssets = GUILayout.Toggle(includeSubAssets, "SubAssets", EditorStyles.toolbarButton);
+            if (EditorGUI.EndChangeCheck())
+                dtv.Reload();
+            
+            GUILayout.FlexibleSpace();
+            if(GUILayout.Button("Clear", EditorStyles.toolbarButton))
+            {
+                watched.Clear();
+                dtv.Reload();
+            }
+        }
+
+        if (dtv == null)
+        {
+            dtv = new DependencyTreeView(new TreeViewState());
+            dtv.Reload();
+        }
+
+        GUILayout.FlexibleSpace();
+
+        dtv.OnGUI(new Rect(0,22,position.width, position.height -22));
+    }
+
+    class DependencyTreeView : TreeView
+    {
+        Dictionary<int, DependencyTreeViewItem> items;
+
+        public DependencyTreeView(TreeViewState tvs): base(tvs)
+        {
+            items = null;
+        }
+
+        protected override TreeViewItem BuildRoot()
+        {
+            if (items == null)
+                items = new Dictionary<int, DependencyTreeViewItem>(); 
+
+            items.Clear();
+
+            int id = -1;
+            var tvi = new TreeViewItem(++id, -1, "Root");
+
+            if(watched == null || watched.Count == 0)
+                tvi.AddChild(AddWatchedItem(null, 0, ref id));
+            else
+            {
+                try
+                {
+                    int i = 0;
+                    foreach (var item in watched)
+                    {
+                        EditorUtility.DisplayProgressBar("Asset Dependencies", $"Loading info for {item.name}...", (float)i/watched.Count);
+                        tvi.AddChild(AddWatchedItem(item, 0, ref id));
+                        i++;
+                    }
+
+                }
+                finally
+                {
+                    EditorUtility.ClearProgressBar();
+                }
+            }
+
+
+            return tvi;
+        }
+
+        DependencyTreeViewItem AddWatchedItem(Object watchedObject, int depth, ref int id)
+        {
+            int i = ++id;
+            var tvi = new DependencyTreeViewItem(i, depth, watchedObject);
+            items.Add(i, tvi);
+
+            List<Object> dependencies = new List<Object>();
+
+            if (includeSubAssets && depth == 0)
+            {
+                // Search all SubAssets (only if this is the main asset)
+                foreach (var c in AssetDatabase.LoadAllAssetsAtPath(AssetDatabase.GetAssetPath(watchedObject)))
+                {
+                    if (c == watchedObject)
+                        continue;
+                    else if(c.hideFlags != 0)
+                        dependencies.Add(c);
+                }
+            }
+
+            // Search for dependencies
+            foreach(var d in AssetDatabase.GetDependencies(AssetDatabase.GetAssetPath(watchedObject), false))
+            {
+                dependencies.Add(AssetDatabase.LoadMainAssetAtPath(d));
+            }
+
+
+            foreach (var depObj in dependencies)
+            {
+
+                if (depObj == watchedObject)
+                {
+                    Debug.LogWarning("Duplicate");
+                    continue;
+                }
+
+                if (depObj.GetType() == typeof(MonoScript) && !includeMonoScript)
+                    continue;
+
+                var tvc = AddWatchedItem(depObj, depth + 1, ref id);
+                tvi.AddChild(tvc);
+
+            }
+
+            return tvi;
+        }
+
+        protected override void DoubleClickedItem(int id)
+        {
+            var obj = items[id].target;
+            if (obj != null)
+                Selection.activeObject = obj;
+        }
+
+        class DependencyTreeViewItem : TreeViewItem
+        {
+            public readonly Object target;
+
+            public DependencyTreeViewItem(int id, int depth, Object obj) : base(id, depth, obj == null? "(No Items)" : obj.name)
+            {
+                target = obj;
+                try
+                {
+                    this.icon = EditorGUIUtility.ObjectContent(obj, obj.GetType()).image as Texture2D;
+                    this.displayName = $"{obj.name} ({obj.GetType().Name})";
+                }
+                catch
+                {
+                    this.icon = EditorGUIUtility.IconContent("GameObject Icon").image as Texture2D;
+                }
+
+            }
+        }
+    }
+
+    static class Styles
+    {
+        public static GUIStyle toolbarButton;
+        public static Color highlightColor = new Color(1.0f, 1.5f, 2.0f);
+
+        static Styles()
+        {
+            toolbarButton = new GUIStyle(EditorStyles.toolbarButton);
+            toolbarButton.alignment = TextAnchor.MiddleLeft;
+        }
+
+    }
+}

Editor/AssetDependencyWindow/AssetDependencyWindow.cs.meta

+fileFormatVersion: 2
+guid: ca37185f702b3a044ab20f50df11d903
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+  serializedVersion: 2
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+  assetBundleName: 
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