Refactor SetMainViewport stuff

pkdawson · May 5, 2024 · 1e29a4e · 1e29a4e
1 parent 6fd8549
commit 1e29a4e
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Showing 5 changed files with 42 additions and 39 deletions.
diff --git a/addons/imgui-godot/ImGuiGodot/ImGuiController.cs b/addons/imgui-godot/ImGuiGodot/ImGuiController.cs
@@ -24,8 +24,7 @@ public override void _Ready()
 
         public override void _Process(double delta)
         {
-            Vector2I vpSize = ImGuiLayer.Instance!.ViewportSize;
-            State.Instance.Update(delta, vpSize.ToImVec2());
+            State.Instance.Update(delta, State.Instance.ViewportSize.ToImVec2());
         }
     }
 
@@ -48,7 +47,7 @@ public override void _EnterTree()
         AddChild(_helper);
 
         Signaler = GetParent();
-        AddChild(new ImGuiLayer());
+        SetMainViewport(_window);
     }
 
     public override void _Ready()
@@ -63,7 +62,7 @@ public override void _ExitTree()
 
     public override void _Process(double delta)
     {
-        ImGuiLayer.Instance!.UpdateViewport();
+        State.Instance.Layer.UpdateViewport();
         Signaler.EmitSignal("imgui_layout");
         State.Instance.Render();
     }
@@ -73,31 +72,48 @@ public override void _Notification(int what)
         Internal.Input.ProcessNotification(what);
     }
 
+    public void OnLayerExiting()
+    {
+        // an ImGuiLayer is being destroyed without calling SetMainViewport
+        if (State.Instance.Layer.GetViewport() != _window)
+        {
+            // revert to main window
+            SetMainViewport(_window);
+        }
+    }
+
     public void SetMainViewport(Viewport vp)
     {
-        ImGuiLayer? oldLayer = ImGuiLayer.Instance;
-        ImGuiLayer.Instance = null;
-        oldLayer?.Free();
+        ImGuiLayer? oldLayer = State.Instance.Layer;
+        if (oldLayer != null)
+        {
+            oldLayer.TreeExiting -= OnLayerExiting;
+            oldLayer.QueueFree();
+        }
+
+        var newLayer = new ImGuiLayer();
+        newLayer.TreeExiting += OnLayerExiting;
 
         if (vp is Window window)
         {
             State.Instance.Input = new Internal.Input();
             if (window == _window)
-                AddChild(new ImGuiLayer());
+                AddChild(newLayer);
             else
-                window.AddChild(new ImGuiLayer());
+                window.AddChild(newLayer);
             ImGui.GetIO().BackendFlags |= ImGuiBackendFlags.PlatformHasViewports;
         }
         else if (vp is SubViewport svp)
         {
             State.Instance.Input = new InputLocal();
-            svp.AddChild(new ImGuiLayer());
+            svp.AddChild(newLayer);
             ImGui.GetIO().BackendFlags &= ~ImGuiBackendFlags.PlatformHasViewports;
         }
         else
         {
             throw new System.ArgumentException("secret third kind of viewport??", nameof(vp));
         }
+        State.Instance.Layer = newLayer;
     }
 
     private void CheckContentScale()

diff --git a/addons/imgui-godot/ImGuiGodot/ImGuiLayer.cs b/addons/imgui-godot/ImGuiGodot/ImGuiLayer.cs
@@ -7,8 +7,6 @@ namespace ImGuiGodot;
 
 public partial class ImGuiLayer : CanvasLayer
 {
-    public static ImGuiLayer? Instance { get; set; }
-
     private Rid _subViewportRid;
     private Vector2I _subViewportSize = Vector2I.Zero;
     private Rid _canvasItem;
@@ -19,12 +17,8 @@ public partial class ImGuiLayer : CanvasLayer
 
     public override void _EnterTree()
     {
-        if (Instance != null)
-            throw new System.InvalidOperationException();
-        Instance = this;
-
         Name = "ImGuiLayer";
-        Layer = State.Instance.Layer;
+        Layer = State.Instance.LayerNum;
 
         _parentViewport = GetViewport();
         _subViewportRid = AddLayerSubViewport(this);
@@ -45,14 +39,6 @@ public override void _ExitTree()
     {
         RenderingServer.FreeRid(_canvasItem);
         RenderingServer.FreeRid(_subViewportRid);
-
-        if (Instance == this)
-        {
-            Instance = null;
-            Window mainWindow = ImGuiController.Instance.GetWindow();
-            if (_parentViewport != mainWindow)
-                ImGuiController.Instance.SetMainViewport(mainWindow);
-        }
     }
 
     private void OnChangeVisibility()
@@ -83,20 +69,22 @@ public void UpdateViewport()
     {
         if (_visible)
         {
+            Vector2I vpSize;
 #pragma warning disable IDE0045 // Convert to conditional expression
             if (_parentViewport is Window w)
-                ViewportSize = w.Size;
+                vpSize = w.Size;
             else if (_parentViewport is SubViewport svp)
-                ViewportSize = svp.Size;
+                vpSize = svp.Size;
             else
                 throw new System.InvalidOperationException();
 #pragma warning restore IDE0045 // Convert to conditional expression
+            State.Instance.ViewportSize = vpSize;
 
             var ft = _parentViewport.GetFinalTransform();
-            if (_subViewportSize != ViewportSize || _finalTransform != ft)
+            if (_subViewportSize != vpSize || _finalTransform != ft)
             {
                 // this is more or less how SubViewportContainer works
-                _subViewportSize = ViewportSize;
+                _subViewportSize = vpSize;
                 _finalTransform = ft;
                 RenderingServer.ViewportSetSize(
                     _subViewportRid,

diff --git a/addons/imgui-godot/ImGuiGodot/Internal/BackendNet.cs b/addons/imgui-godot/ImGuiGodot/Internal/BackendNet.cs
@@ -23,12 +23,8 @@ public float Scale
 
     public bool Visible
     {
-        get => ImGuiLayer.Instance?.Visible ?? false;
-        set
-        {
-            if (ImGuiLayer.Instance != null)
-                ImGuiLayer.Instance!.Visible = value;
-        }
+        get => State.Instance.Layer.Visible;
+        set => State.Instance.Layer.Visible = value;
     }
 
     public void AddFont(FontFile fontData, int fontSize, bool merge, ushort[]? glyphRanges)

diff --git a/addons/imgui-godot/ImGuiGodot/Internal/Input.cs b/addons/imgui-godot/ImGuiGodot/Internal/Input.cs
@@ -49,7 +49,7 @@ protected virtual void UpdateMousePos(ImGuiIOPtr io)
             }
             else
             {
-                var winPos = ImGuiLayer.Instance!.GetWindow().Position;
+                var winPos = State.Instance.Layer.GetWindow().Position;
                 io.AddMousePosEvent(mousePos.X - winPos.X, mousePos.Y - winPos.Y);
             }
         }
@@ -104,7 +104,7 @@ protected void ProcessSubViewportWidget(InputEvent evt)
                 var mousePos = DisplayServer.MouseGetPosition();
                 var windowPos = Vector2I.Zero;
                 if (!io.ConfigFlags.HasFlag(ImGuiConfigFlags.ViewportsEnable))
-                    windowPos = ImGuiLayer.Instance!.GetWindow().Position;
+                    windowPos = State.Instance.Layer.GetWindow().Position;
 
                 mouseEvent.Position = new Vector2(
                     mousePos.X - windowPos.X - CurrentSubViewportPos.X,

diff --git a/addons/imgui-godot/ImGuiGodot/Internal/State.cs b/addons/imgui-godot/ImGuiGodot/Internal/State.cs
@@ -23,9 +23,12 @@ private enum RendererType
     internal Fonts Fonts { get; }
     internal Input Input { get; set; }
     internal IRenderer Renderer { get; }
+
     internal float Scale { get; set; } = 1.0f;
     internal float JoyAxisDeadZone { get; set; } = 0.15f;
-    internal int Layer { get; private set; } = 128;
+    internal int LayerNum { get; private set; } = 128;
+    internal Vector2I ViewportSize { get; set; }
+    internal ImGuiLayer Layer { get; set; } = null!;
 
     internal static State Instance { get; set; } = null!;
 
@@ -122,7 +125,7 @@ public static void Init(Resource cfg)
         Instance = new(renderer)
         {
             Scale = (float)cfg.Get("Scale"),
-            Layer = (int)cfg.Get("Layer")
+            LayerNum = (int)cfg.Get("Layer")
         };
 
         ImGui.GetIO().SetIniFilename((string)cfg.Get("IniFilename"));