Added script to show fungus icon in the hierarchy

Assets/Fungus/Scripts/Editor/HierarchyIcons.cs

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+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+using UnityEditor;
+using System.Linq;
+
+namespace Fungus
+{
+    /// <summary>
+    /// Static class that hooks into the hierachy changed and item gui callbacks to put
+    /// a fungus icon infront of all GOs that have a flowchart on them
+    /// 
+    /// Reference; http://answers.unity3d.com/questions/431952/how-to-show-an-icon-in-hierarchy-view.html
+    /// </summary>
+    [InitializeOnLoad]
+    public class HierarchyIcons
+    {
+        // the fungus mushroom icon
+        static Texture2D textureIcon;
+
+        //sorted list of the GO instance IDs that have flowcharts on them
+        static List<int> flowchartIDs = new List<int>();
+
+        static HierarchyIcons()
+        {
+            //please don't move the fungus icon :(
+            textureIcon = AssetDatabase.LoadAssetAtPath("Assets/Fungus/Textures/ScriptIcon.png", typeof(Texture2D)) as Texture2D;
+            
+            EditorApplication.hierarchyWindowItemOnGUI += HierarchyIconCallback;
+            EditorApplication.hierarchyWindowChanged += HierarchyChanged;
+        }
+
+        //track all gameobjectIds that have flowcharts on them
+        static void HierarchyChanged()
+        {
+            flowchartIDs.Clear();
+
+            var flowcharts = GameObject.FindObjectsOfType<Flowchart>();
+
+            flowchartIDs = flowcharts.Select(x => x.gameObject.GetInstanceID()).Distinct().ToList();
+            flowchartIDs.Sort();
+        }
+
+        //Draw icon if the isntance id is in our cached list
+        static void HierarchyIconCallback(int instanceID, Rect selectionRect)
+        {
+            // place the icon to the left of the element
+            Rect r = new Rect(selectionRect);
+            r.x = 0;
+            r.width = r.height;
+
+            //GameObject go = EditorUtility.InstanceIDToObject(instanceID) as GameObject;
+            
+            //binary search as it is much faster to cache and int bin search than GetComponent
+            //  should be less GC too
+            if (flowchartIDs.BinarySearch(instanceID) >= 0)
+                GUI.Label(r, textureIcon);
+        }
+    }
+}

Assets/Fungus/Scripts/Editor/HierarchyIcons.cs.meta

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+guid: a347e274da09aa44dbb68f1375508d11
+timeCreated: 1500115754
+licenseType: Free
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