Works & tested on the platforms Windows, Linux and MacOS. Minimal Resolution 1600 x 900.

Author: Kersoph

Lessons/.gdignore

@@ -3,13 +3,47 @@ namespace Osls.Environment
     public static class EnvironmentPaths
     {
         /// <summary>
-        /// Gets the globalized lesson folder path
+        /// Gets the forced globalized lesson folder path.
+        /// ProjectSettings.GlobalizePath will not return the system path for res:// in export
+        /// Currently there seems to be no way to get the execution folder directly,
+        /// but we can use the exe path but only in export mode.
         /// </summary>
         public static string LessonsFolderPath
         {
             get
             {
-                return Godot.ProjectSettings.GlobalizePath("res://lessons/");
+                string path = Godot.ProjectSettings.GlobalizePath(InternalLessonsFolderPath);
+                if (path.Contains(":"))
+                {
+                    return path;
+                }
+                path = Godot.OS.GetExecutablePath();
+                int lastIndex = path.LastIndexOf("/");
+                path = path.Substring(0, lastIndex + 1);
+                return path + "lessons/";
+            }
+        }
+        
+        /// <summary>
+        /// Gets the globalized alternative lesson folder path if the regular does not work.
+        /// Especially used for MacOS as the res path is not writeable.
+        /// </summary>
+        public static string LessonsFolderPathAlternative
+        {
+            get
+            {
+                return Godot.ProjectSettings.GlobalizePath("user://lessons/");
+            }
+        }
+        
+        /// <summary>
+        /// Gets the internal packed lesson folder path. Read only.
+        /// </summary>
+        public static string InternalLessonsFolderPath
+        {
+            get
+            {
+                return "res://lessons/";
             }
         }
     }

data/core/environment/EnvironmentPaths.cs

@@ -1,10 +1,11 @@
-[gd_scene load_steps=6 format=2]
+[gd_scene load_steps=7 format=2]
 
 [ext_resource path="res://data/core/landing_page/LandingPageNode.cs" type="Script" id=1]
 [ext_resource path="res://data/core/landing_page/LessonsNode.cs" type="Script" id=2]
 [ext_resource path="res://data/core/landing_page/LessonSelectionGridNode.cs" type="Script" id=3]
 [ext_resource path="res://data/core/lesson/viewer/LessonView.tscn" type="PackedScene" id=4]
 [ext_resource path="res://data/core/landing_page/lesson_source_controller/images/DiagramScreenshot.png" type="Texture" id=5]
+[ext_resource path="res://data/core/landing_page/lesson_source_controller/LessonController.tscn" type="PackedScene" id=6]
 
 [node name="LandingPage" type="Node"]
 script = ExtResource( 1 )
@@ -19,6 +20,9 @@ margin_left = 80.0
 margin_top = 1.0
 margin_right = -513.0
 rect_clip_content = true
+__meta__ = {
+"_edit_use_anchors_": false
+}
 
 [node name="Background" type="TextureRect" parent="LessonsNode/LessonSelectorContainer"]
 modulate = Color( 0.956863, 0.94902, 0.917647, 1 )
@@ -53,6 +57,7 @@ custom_constants/vseparation = 50
 custom_constants/hseparation = 50
 columns = 4
 script = ExtResource( 3 )
+_lessonControllerScene = ExtResource( 6 )
 
 [node name="LessonPreviewBackground" type="ColorRect" parent="LessonsNode"]
 anchor_left = 1.0

data/core/landing_page/LandingPage.tscn

@@ -1,5 +1,4 @@
 using Godot;
-using Osls.Environment;
 
 
 namespace Osls.LandingPage
@@ -11,7 +10,7 @@ namespace Osls.LandingPage
     public class LessonSelectionGridNode : GridContainer
     {
         #region ==================== Fields ====================
-        private const string LessonControllerScene = "res://data/core/landing_page/lesson_source_controller/LessonController.tscn";
+        [Export] private PackedScene _lessonControllerScene;
         private LessonControllerNode[] _lessonNodes;
         #endregion
 
@@ -21,7 +20,7 @@ public override void _Ready()
         {
             try
             {
-                LessonEntity[] lessons = LoadLessons();
+                LessonEntity[] lessons = LessonCollector.LoadLessons();
                 CreateButtons(lessons);
             }
             catch (System.Exception e)
@@ -57,28 +56,13 @@ public void StartSelectedLesson(LessonControllerNode node)
         #endregion
 
 
-        #region ==================== Private Methods ====================
-        private LessonEntity[] LoadLessons()
-        {
-            string[] LessonPaths = System.IO.Directory.GetDirectories(EnvironmentPaths.LessonsFolderPath);
-            System.Array.Sort<string>(LessonPaths);
-            LessonEntity[] lessonEntities = new LessonEntity[LessonPaths.Length];
-            for (int i = 0; i < LessonPaths.Length; i++)
-            {
-                LessonEntity lessonData = new LessonEntity(LessonPaths[i]);
-                lessonData.LoadFolderContent();
-                lessonEntities[i] = lessonData;
-            }
-            return lessonEntities;
-        }
-        
+        #region ==================== Helpers ====================
         private void CreateButtons(LessonEntity[] lessons)
         {
-            PackedScene packedControllerNode = (PackedScene)GD.Load(LessonControllerScene);
             _lessonNodes = new LessonControllerNode[lessons.Length];
             for (int i = 0; i < lessons.Length; i++)
             {
-                LessonControllerNode controllerNode = (LessonControllerNode)packedControllerNode.Instance();
+                LessonControllerNode controllerNode = (LessonControllerNode)_lessonControllerScene.Instance();
                 controllerNode.SetLessonInfo(lessons[i], this);
                 AddChild(controllerNode);
                 _lessonNodes[i] = controllerNode;

data/core/landing_page/LessonSelectionGridNode.cs

@@ -0,0 +1,107 @@
+using Godot;
+using Osls.Environment;
+
+
+namespace Osls
+{
+    public static class LessonCollector
+    {
+        #region ==================== Public Methods ====================
+        /// <summary>
+        /// Loads all aviable lessons at the locations:
+        /// res://lessons/ and as an alternative user://lesons
+        /// If it does not exist we try to create a default directory at
+        /// res://lessons/ and as an alternative user://lesons
+        /// </summary>
+        public static LessonEntity[] LoadLessons()
+        {
+            string[] LessonPaths = GetLessonPaths();
+            System.Array.Sort<string>(LessonPaths);
+            LessonEntity[] lessonEntities = new LessonEntity[LessonPaths.Length];
+            for (int i = 0; i < LessonPaths.Length; i++)
+            {
+                LessonEntity lessonData = new LessonEntity(LessonPaths[i]);
+                lessonData.LoadFolderContent();
+                lessonEntities[i] = lessonData;
+            }
+            return lessonEntities;
+        }
+        #endregion
+        
+        
+        #region ==================== Helpers ====================
+        /// <summary>
+        /// Gets the base directories for the lesson folders.
+        /// It first looks under the res folder and then in the user path.
+        /// If none could be found we create a new dir and copy the default data in it.
+        /// </summary>
+        private static string[] GetLessonPaths()
+        {
+            string[] LessonPaths = TryLoad(EnvironmentPaths.LessonsFolderPath);
+            if (LessonPaths != null && LessonPaths.Length > 0) return LessonPaths;
+            LessonPaths = TryLoad(EnvironmentPaths.LessonsFolderPathAlternative);
+            if (LessonPaths != null && LessonPaths.Length > 0) return LessonPaths;
+            if (CreateDefault(EnvironmentPaths.LessonsFolderPath))
+            {
+                return TryLoad(EnvironmentPaths.LessonsFolderPath);
+            }
+            if (CreateDefault(EnvironmentPaths.LessonsFolderPathAlternative))
+            {
+                return TryLoad(EnvironmentPaths.LessonsFolderPathAlternative);
+            }
+            GD.PushWarning("Could not find any lessons at: " + EnvironmentPaths.LessonsFolderPath + " and " + EnvironmentPaths.LessonsFolderPathAlternative);
+            return new string[0];
+        }
+        
+        private static string[] TryLoad(string path)
+        {
+            if (!System.IO.Directory.Exists(path)) return new string[0];
+            return System.IO.Directory.GetDirectories(path);
+        }
+        
+        /// <summary>
+        /// Returns true if the default files could be copied to the base path
+        /// </summary>
+        private static bool CreateDefault(string basePath)
+        {
+            GD.Print("Try to copy " + EnvironmentPaths.InternalLessonsFolderPath + " to " + basePath);
+            Directory targetDir = new Directory();
+            Directory internalDir = new Directory();
+            Error result = targetDir.MakeDirRecursive(basePath);
+            Error internalresult = internalDir.Open(EnvironmentPaths.InternalLessonsFolderPath);
+            if (result != Error.Ok || internalresult != Error.Ok) return false;
+            ProcessDirectory(EnvironmentPaths.InternalLessonsFolderPath, basePath);
+            return true;
+        }
+        
+        /// <summary>
+        /// Copies all files from the given internal directory to the given path.
+        /// As the internal data is packed we need to use godots directory system.
+        /// </summary>
+        private static void ProcessDirectory(string internalPath, string externalPath)
+        {
+            Directory internalDir = new Directory();
+            Error result = internalDir.Open(internalPath);
+            if (result != Error.Ok) return;
+            internalDir.ListDirBegin(true, true);
+            while (true)
+            {
+                string item = internalDir.GetNext();
+                if (string.IsNullOrEmpty(item)) return;
+                if (internalDir.CurrentIsDir())
+                {
+                    Directory targetDir = new Directory();
+                    GD.Print("create " + externalPath + item + "/");
+                    targetDir.MakeDir(externalPath + item + "/");
+                    ProcessDirectory(internalPath + item + "/", externalPath + item + "/");
+                }
+                else
+                {
+                    GD.Print("copy " + internalPath + item + " to " + externalPath + item);
+                    internalDir.Copy(internalPath + item, externalPath + item);
+                }
+            }
+        }
+        #endregion
+    }
+}

data/core/lesson/LessonCollector.cs

@@ -118,7 +118,7 @@ public void SetAndSaveStars(int stars)
         #region ==================== Helpers ====================
         /// <summary>
         /// Loads the description json as a godot dictionary.
-        /// It is different than the System.Runtime.Serialization json attribute deserilisation.
+        /// It is different than the System.Runtime.Serialization json attribute deserialization.
         /// But it is sufficient for our needs.
         /// </summary>
         private void LoadDescriptionDictionary()

data/core/lesson/LessonEntity.cs

@@ -5,7 +5,7 @@ platform="Windows Desktop"
 runnable=true
 custom_features=""
 export_filter="all_resources"
-include_filter=""
+include_filter="lessons/*"
 exclude_filter=""
 export_path="../Export/Windows/Open Sequential Logic Simulation.exe"
 script_export_mode=1
@@ -47,7 +47,7 @@ platform="Linux/X11"
 runnable=true
 custom_features=""
 export_filter="all_resources"
-include_filter=""
+include_filter="lessons/*"
 exclude_filter=""
 export_path="../Export/Linux/Open Sequential Logic Simulation.x86_64"
 script_export_mode=1
@@ -72,7 +72,7 @@ platform="Mac OSX"
 runnable=true
 custom_features=""
 export_filter="all_resources"
-include_filter=""
+include_filter="lessons/*"
 exclude_filter=""
 export_path="../Export/MacOS/Open Sequential Logic Simulation.zip"
 script_export_mode=1