Base Commit

Editor/NewSceneWindow.meta

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Editor/NewSceneWindow/NewSceneWindow.cs

+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+using UnityEditor;
+using UnityEditor.SceneManagement;
+
+namespace GameplayIngredients.Editor
+{
+    public class NewSceneWindow : EditorWindow
+    {
+        const int WindowWidth = 640;
+        const int WindowHeight = 380;
+
+        [MenuItem("File/New Scene From Template... &%N", priority = 1)]
+        static void ShowNewSceneWindow()
+        {
+            GetWindow<NewSceneWindow>(true);
+        }
+
+        private void OnEnable()
+        {
+            titleContent = new GUIContent("New Scene From Template");
+            this.position = new Rect((Screen.width / 2.0f) - WindowWidth / 2, (Screen.height / 2.0f) - WindowHeight / 2, WindowWidth, WindowHeight);
+            this.minSize = new Vector2(WindowWidth, WindowHeight);
+            this.maxSize = new Vector2(WindowWidth, WindowHeight);
+            ReloadList();
+        }
+
+        private void OnGUI()
+        {
+            GUILayout.Label("Available Templates");
+            using (new GUILayout.HorizontalScope(GUILayout.ExpandHeight(true)))
+            {
+                using (new GUILayout.VerticalScope(Styles.helpBox, GUILayout.Width(180)))
+                {
+                    DrawTemplateList();
+                }
+                GUILayout.Space(8);
+                using (new GUILayout.VerticalScope(Styles.helpBox))
+                {
+                    DrawTemplateDetails();
+                }
+            }
+            using (new GUILayout.HorizontalScope())
+            {
+                GUILayout.FlexibleSpace();
+                if(GUILayout.Button("Create"))
+                {
+                    // Do Something
+                    this.Close();
+                }
+            }
+        }
+
+        public static void ReloadList()
+        {
+            if (templateLists == null)
+                templateLists = new List<SceneTemplateList>();
+            else
+                templateLists.Clear();
+
+            string[] all = AssetDatabase.FindAssets("t:" + typeof(SceneTemplateList).Name);
+            foreach(var guid in all)
+            {
+                templateLists.Add(AssetDatabase.LoadAssetAtPath<SceneTemplateList>(AssetDatabase.GUIDToAssetPath(guid)));
+            }
+        }
+
+        static List<SceneTemplateList> templateLists;
+
+        Vector2 scrollList = Vector2.zero;
+
+        void DrawTemplateList()
+        {
+            GUILayout.BeginScrollView(scrollList);
+
+            GUILayout.FlexibleSpace();
+            GUILayout.EndScrollView();
+        }
+
+        void DrawTemplateDetails()
+        {
+            GUILayout.FlexibleSpace();
+        }
+
+        static class Styles
+        {
+            public static GUIStyle buttonLeft;
+            public static GUIStyle buttonMid;
+            public static GUIStyle buttonRight;
+
+            public static GUIStyle helpBox;
+
+            static Styles()
+            {
+                buttonLeft = new GUIStyle(EditorStyles.miniButtonLeft);
+                buttonMid = new GUIStyle(EditorStyles.miniButtonMid);
+                buttonRight = new GUIStyle(EditorStyles.miniButtonRight);
+                buttonLeft.fontSize = 12;
+                buttonMid.fontSize = 12;
+                buttonRight.fontSize = 12;
+
+                helpBox = new GUIStyle(EditorStyles.helpBox);
+                helpBox.padding = new RectOffset(12, 12, 12, 12);
+            }
+        }
+    }
+}

Editor/NewSceneWindow/NewSceneWindow.cs.meta

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Editor/NewSceneWindow/SceneTemplateList.cs

+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+using UnityEditor;
+
+namespace GameplayIngredients.Editor
+{
+    public class SceneTemplateList : ScriptableObject
+    {
+        [MenuItem("Assets/Create/Scene Template List", priority = 201)]
+        static void CreateSceneTemplateListAsset()
+        {
+            AssetFactory.CreateAssetInProjectWindow<SceneTemplateList>("", "New SceneTemplateList.asset");
+        }
+
+        public string ListName = "New Template List";
+        public SceneWindowTemplate[] Templates;
+    }
+
+    [System.Serializable]
+    public struct SceneWindowTemplate
+    {
+        public string Name;
+        [Multiline]
+        public string Description;
+        [NonNullCheck]
+        public SceneAsset Scene;
+    }
+}

Editor/NewSceneWindow/SceneTemplateList.cs.meta

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