Add scene switcher for controlled scene switches

project.godot

@@ -11,7 +11,7 @@ config_version=5
 [application]
 
 config/name="gmtk24"
-run/main_scene="res://scenes/demo/demo.tscn"
+run/main_scene="res://scenes/entrypoint_scene.tscn"
 config/features=PackedStringArray("4.3", "C#", "Forward Plus")
 config/icon="res://misc/icon.svg"
 

scenes/entrypoint_scene.tscn

@@ -0,0 +1,27 @@
+[gd_scene load_steps=4 format=3 uid="uid://c5ksyousvxx7x"]
+
+[ext_resource type="PackedScene" uid="uid://dv81sy34l8ice" path="res://scenes/stairs/stairs.tscn" id="1_00r22"]
+[ext_resource type="Script" path="res://scripts/SceneSwitcher.cs" id="1_ps0jf"]
+[ext_resource type="PackedScene" uid="uid://8po7ftboqq4k" path="res://scenes/demo/demo.tscn" id="2_rf0rf"]
+
+[node name="EntrypointScene" type="Node" node_paths=PackedStringArray("LoadingScreen")]
+process_mode = 3
+script = ExtResource("1_ps0jf")
+AddedLoadingScreenSeconds = 0.3
+LoadingScreen = NodePath("LoadingScreen")
+DemoScene = ExtResource("2_rf0rf")
+StairsScene = ExtResource("1_00r22")
+
+[node name="LoadingScreen" type="CenterContainer" parent="."]
+anchors_preset = 15
+anchor_right = 1.0
+anchor_bottom = 1.0
+offset_left = 4.0
+offset_right = 4.0
+grow_horizontal = 2
+grow_vertical = 2
+
+[node name="Label" type="Label" parent="LoadingScreen"]
+layout_mode = 2
+theme_override_font_sizes/font_size = 36
+text = "Loading..."

scenes/interface/pause_menu.tscn

@@ -73,10 +73,9 @@ text = "Continue"
 custom_minimum_size = Vector2(340, 200)
 layout_mode = 2
 theme_override_font_sizes/font_size = 11
-current_tab = 3
+current_tab = 0
 
 [node name="General settings" type="MarginContainer" parent="CenterContainer/HBoxContainer/OptionsAndButtonsContainer/MarginContainer/Options and buttons/TabContainer"]
-visible = false
 layout_mode = 2
 theme_override_constants/margin_left = 10
 theme_override_constants/margin_top = 10
@@ -213,6 +212,7 @@ size_flags_horizontal = 3
 action_mode = 0
 
 [node name="Graphics" type="MarginContainer" parent="CenterContainer/HBoxContainer/OptionsAndButtonsContainer/MarginContainer/Options and buttons/TabContainer"]
+visible = false
 layout_mode = 2
 theme_override_constants/margin_left = 10
 theme_override_constants/margin_top = 10

scripts/SceneSwitcher.cs

@@ -0,0 +1,103 @@
+using System.Threading;
+using Godot;
+
+namespace Gmtk24 {
+    public partial class SceneSwitcher : Node {
+        public enum Scene {
+            Demo,
+            Stairs,
+        }
+
+        /// <summary>This is the entrypoint of the godot project, and never gets
+        /// unloaded. Set when the entrypoint scene is loaded.</summary>
+        public static SceneSwitcher Singleton { get; private set; }
+
+        [Export]
+        public float AddedLoadingScreenSeconds = 0.5f;
+        [Export]
+        public Control LoadingScreen;
+        [Export]
+        public PackedScene DemoScene;
+        [Export]
+        public PackedScene StairsScene;
+
+        private PackedScene NextScene = null;
+        private Node InstantiatedScene = null;
+        private bool SceneLoaded = false;
+        /// <summary>The instantiation is deferred a bit to let the loading
+        /// screen actually render in case the loading takes more than a few
+        /// milliseconds.</summary>
+        private float SceneLoadCooldown = 0;
+
+        public override void _Ready() {
+            Singleton = this;
+            SwitchToScene(Scene.Demo);
+        }
+
+        public override void _UnhandledInput(InputEvent @event) {
+            if (@event is InputEventKey keyEv && keyEv.Pressed && keyEv.CtrlPressed) {
+                if (keyEv.Keycode == Key.F1) {
+                    SwitchToScene(Scene.Demo);
+                    GetViewport().SetInputAsHandled();
+                }
+                if (keyEv.Keycode == Key.F2) {
+                    SwitchToScene(Scene.Stairs);
+                    GetViewport().SetInputAsHandled();
+                }
+            }
+        }
+
+        public override void _Process(double delta) {
+            if (!SceneLoaded) {
+                SceneLoadCooldown -= (float)delta;
+                if (SceneLoadCooldown <= 0 && NextScene != null) {
+                    LoadNextScene();
+                    NextScene = null;
+                    SceneLoaded = true;
+                    LoadingScreen.Visible = false;
+                }
+            }
+        }
+
+        public void SwitchToScene(Scene newScene) {
+            PackedScene sceneToInstantiate = null;
+            switch (newScene) {
+                case Scene.Demo:
+                    sceneToInstantiate = DemoScene;
+                    break;
+                case Scene.Stairs:
+                    sceneToInstantiate = StairsScene;
+                    break;
+            }
+            if (sceneToInstantiate == null) {
+                GD.PrintErr("Tried to switch scenes to Scene." + newScene + " but it hasn't been set up in the entrypoint scene!");
+                return;
+            }
+
+            NextScene = sceneToInstantiate;
+
+            if (IsInstanceValid(InstantiatedScene)) {
+                RemoveChild(InstantiatedScene);
+                InstantiatedScene.QueueFree();
+            }
+
+            LoadingScreen.Visible = true;
+            SceneLoadCooldown = AddedLoadingScreenSeconds;
+            SceneLoaded = false;
+        }
+
+        private void LoadNextScene() {
+            if (NextScene == null) {
+                return;
+            }
+
+            InstantiatedScene = NextScene.Instantiate();
+
+            if (InstantiatedScene.ProcessMode == ProcessModeEnum.Inherit) {
+                InstantiatedScene.ProcessMode = ProcessModeEnum.Pausable;
+            }
+            AddChild(InstantiatedScene);
+            MoveChild(InstantiatedScene, 0);
+        }
+    }
+}