Window related updates

- The window state (visibility and bounds) gets preserved when created via context menu. It will not get preserved when created via the ShowUI node.
- Fixes empty crash for some plugins after minimizing (reported window size is zero which some plugins don't like)
- The classes/records EffectHost, PluginState, WindowState are now advanced to not pollute the node browser

src/EffectHost.UI.cs

@@ -1,32 +1,52 @@
 using Microsoft.Extensions.Logging;
-using System.Drawing;
 using System.Windows.Forms;
 using VST3;
 using System.Runtime.InteropServices.Marshalling;
 using System.Reactive.Linq;
 using System.Reactive.Disposables;
 using VL.Lang.PublicAPI;
-using VL.Audio.VST.Internal;
 using VST3.Hosting;
+using System.Drawing;
+using RectangleF = Stride.Core.Mathematics.RectangleF;
+using VL.Core;
 
 namespace VL.Audio.VST;
 
 partial class EffectHost
 {
-    private Form? window;
+    private Window? window;
+
+    /// <summary>
+    /// Shows the UI of the plugin (if available).
+    /// </summary>
+    /// <remarks>
+    /// In case the window was already created via the context menu, it will get re-created to ensure that its bounds are no longer saved to the pin.
+    /// </remarks>
+    /// <param name="bounds">The bounds of the window in pixel. Width and height will only get applied if the plugin allows it.</param>
+    public void ShowUI(Optional<RectangleF> bounds)
+    {
+        // Called from user code, don't track window state
+        ShowUI(bounds.ToNullable(), formWindowState: FormWindowState.Normal, trackWindowState: false);
+    }
 
-    public void ShowUI()
+    private void ShowUI(RectangleF? bounds, FormWindowState? formWindowState, bool trackWindowState)
     {
         if (controller is null)
             return;
 
+        // Ensure tracking state matches the requested state
+        if (window != null && window.IsTracking != trackWindowState)
+        {
+            HideUI();
+        }
+
         if (window is null || window.IsDisposed)
         {
             var view = controller.createView("editor");
             if (view is null || view.isPlatformTypeSupported("HWND") != 0)
                 return;
 
-            window = new Window(this, view);
+            window = new Window(this, view, trackWindowState);
 
             // High DPI support
             var scaleSupport = view as IPlugViewContentScaleSupport;
@@ -35,23 +55,14 @@ public void ShowUI()
                 scaleSupport?.setContentScaleFactor(e.DeviceDpiNew / 96f);
             };
 
-            bounds = boundsPin.Value?.Value ?? default;
-            if (!bounds.IsEmpty)
+            try
             {
-                window.StartPosition = FormStartPosition.Manual;
-                SetWindowBounds(bounds);
+                var plugViewSize = view.getSize();
+                window.ClientSize = new Size(plugViewSize.Width, plugViewSize.Height);
             }
-            else
+            catch (Exception e)
             {
-                try
-                {
-                    var plugViewSize = view.getSize();
-                    window.ClientSize = new Size(plugViewSize.Width, plugViewSize.Height);
-                }
-                catch (Exception e)
-                {
-                    logger.LogError(e, "Failed to get initial view size");
-                }
+                logger.LogError(e, "Failed to get initial view size");
             }
 
             try
@@ -68,34 +79,42 @@ public void ShowUI()
             }
         }
 
+        if (bounds.HasValue)
+        {
+            var b = bounds.Value;
+            window.StartPosition = FormStartPosition.Manual;
+            window.Location = new Point((int)b.X, (int)b.Y);
+            if (window.View.canResize() && b.Width > 0 && b.Height > 0)
+                window.Size = new Size((int)b.Width, (int)b.Height);
+        }
+
+        if (formWindowState.HasValue)
+            window.WindowState = formWindowState.Value;
+
         window.Visible = true;
-        window.Activate();
+
+        if (formWindowState != FormWindowState.Minimized)
+            window.Activate();
     }
 
+    /// <summary>
+    /// Hides the UI of the plugin.
+    /// </summary>
     public void HideUI()
     {
-        window?.Close();
         window?.Dispose();
         window = null;
     }
 
-    void SaveCurrentWindowBounds()
+    void SaveWindowState(WindowState windowState)
     {
-        if (window is null || window.IsDisposed || boundsPin.Value is null)
-            return;
+        // Save in a field to ensure that an upcoming call to ShowUI will use the previous bounds
+        this.windowState = windowState;
 
-        var position = window.DesktopLocation;
-        var bounds = new Stride.Core.Mathematics.RectangleF(position.X, position.Y, window.ClientSize.Width, window.ClientSize.Height);
-        SaveToChannelOrPin(boundsPin.Value, IDevSession.Current?.CurrentSolution, BoundsInputPinName, bounds)?.Confirm(JustWriteToThePin);
-    }
-
-    private void SetWindowBounds(Stride.Core.Mathematics.RectangleF bounds)
-    {
-        if (window is null || window.IsDisposed)
+        if (windowStatePin.Value is null)
             return;
 
-        window.Location = new Point((int)bounds.X, (int)bounds.Y);
-        window.ClientSize = new Size((int)bounds.Width, (int)bounds.Height);
+        SaveToChannelOrPin(windowStatePin.Value, IDevSession.Current?.CurrentSolution, WindowStatePinName, windowState)?.Confirm(JustWriteToThePin);
     }
 
     [GeneratedComClass]
@@ -105,26 +124,44 @@ sealed partial class Window : Form, IPlugFrame
         private readonly IPlugView view;
         private readonly IPlugViewContentScaleSupport? scaleSupport;
         private readonly SingleAssignmentDisposable boundsSubscription = new();
+        private readonly bool trackWindowState;
 
-        public Window(EffectHost effectHost, IPlugView view)
+        public Window(EffectHost effectHost, IPlugView view, bool trackWindowState)
         {
             this.effectHost = effectHost;
             this.view = view;
+            this.trackWindowState = trackWindowState;
             this.scaleSupport = view as IPlugViewContentScaleSupport;
         }
 
+        public IPlugView View => view;
+
+        public bool IsTracking => trackWindowState;
+
+        public WindowState GetWindowState()
+        {
+            var r = WindowState == FormWindowState.Normal ? new Rectangle(Location, Size) : RestoreBounds;
+            return new WindowState(WindowState.ToWindowVisibility(), new RectangleF(r.X, r.Y, r.Width, r.Height));
+        }
+
         protected override void OnHandleCreated(EventArgs e)
         {
             view.setFrame(this);
             view.attached(Handle, "HWND");
             scaleSupport?.setContentScaleFactor(DeviceDpi / 96f);
 
-            boundsSubscription.Disposable = Observable.Merge(
-                Observable.FromEventPattern(this, nameof(ClientSizeChanged)),
-                Observable.FromEventPattern(this, nameof(LocationChanged)))
-                .Throttle(TimeSpan.FromSeconds(0.25))
-                .ObserveOn(SynchronizationContext.Current!)
-                .Subscribe(_ => effectHost.SaveCurrentWindowBounds());
+            if (trackWindowState)
+            {
+                var windowState = GetWindowState();
+                effectHost.SaveWindowState(windowState);
+
+                boundsSubscription.Disposable = Observable.Merge(
+                    Observable.FromEventPattern(this, nameof(ClientSizeChanged)),
+                    Observable.FromEventPattern(this, nameof(LocationChanged)))
+                    .Throttle(TimeSpan.FromSeconds(0.25))
+                    .ObserveOn(SynchronizationContext.Current!)
+                    .Subscribe(_ => effectHost.SaveWindowState(GetWindowState()));
+            }
 
             base.OnHandleCreated(e);
         }
@@ -138,6 +175,17 @@ protected override void OnHandleDestroyed(EventArgs e)
             base.OnHandleDestroyed(e);
         }
 
+        protected override void OnClosed(EventArgs e)
+        {
+            if (trackWindowState)
+            {
+                var windowState = GetWindowState();
+                effectHost.SaveWindowState(windowState with { Visibility = WindowVisibility.Hidden });
+            }
+
+            base.OnClosed(e);
+        }
+
         protected override void OnDpiChanged(DpiChangedEventArgs e)
         {
             scaleSupport?.setContentScaleFactor(e.DeviceDpiNew / 96f);
@@ -147,8 +195,10 @@ protected override void OnDpiChanged(DpiChangedEventArgs e)
 
         protected override void OnClientSizeChanged(EventArgs e)
         {
-            var r = ClientRectangle;
-            view.onSize(new ViewRect() { Left = r.Left, Right = r.Right, Top = r.Top, Bottom = r.Bottom });
+            // Client size is empty when the window is minimized. Don't send that to the view, as it breaks some.
+            var clientSize = ClientSize;
+            if (!clientSize.IsEmpty)
+                view.onSize(new ViewRect() { Left = 0, Right = clientSize.Width, Top = 0, Bottom = clientSize.Height });
 
             base.OnClientSizeChanged(e);
         }

src/EffectHost.cs

@@ -12,6 +12,7 @@
 using VL.Audio.VST.Internal;
 using VL.Core;
 using VL.Core.Commands;
+using VL.Core.CompilerServices;
 using VL.Core.Reactive;
 using VL.Lang.PublicAPI;
 using VL.Lib.Collections;
@@ -21,15 +22,14 @@
 
 namespace VL.Audio.VST;
 
-using StatePin = Pin<IChannel<PluginState>>;
-using AudioPin = Pin<IReadOnlyList<AudioSignal>>;
 using IComponent = VST3.IComponent;
 
 [GeneratedComClass]
+[Smell(SymbolSmell.Advanced)]
 public partial class EffectHost : FactoryBasedVLNode, IVLNode, IHasCommands, IHasLearnMode, IComponentHandler, IComponentHandler2, IDisposable
 {
     internal const string StateInputPinName = "State";
-    internal const string BoundsInputPinName = "Bounds";
+    internal const string WindowStatePinName = "Window State";
     private const Model.SolutionUpdateKind JustWriteToThePin = Model.SolutionUpdateKind.Default & ~Model.SolutionUpdateKind.AffectCompilation & ~Model.SolutionUpdateKind.AddToHistory;
 
     private static readonly ParameterChanges s_noChanges = new();
@@ -58,16 +58,16 @@ public partial class EffectHost : FactoryBasedVLNode, IVLNode, IHasCommands, IHa
     private readonly Subject<Event> outputEvents = new();
 
     private readonly IVLPin[] inputs, outputs;
-    private readonly Pin<IChannel<RectangleF>> boundsPin;
+    private readonly Pin<IChannel<WindowState>> windowStatePin;
     private readonly Pin<IObservable<IMidiMessage>> midiInputPin, midiOutputPin;
     private readonly Pin<Dictionary<string, object>> parametersPin;
     private readonly Pin<bool> applyPin;
     private readonly IChannel<bool> learnMode = Channel.Create(false);
 
     private PluginState? state;
     private bool stateIsBeingSet;
-    private RectangleF bounds;
-    private AudioPin audioInputPin, audioOutputPin;
+    private WindowState? windowState;
+    private Pin<IReadOnlyList<AudioSignal>> audioInputPin, audioOutputPin;
     private IObservable<IMidiMessage>? midiInput;
     private readonly Dictionary<string, object> inputValues = new();
     private bool apply;
@@ -86,7 +86,7 @@ public partial class EffectHost : FactoryBasedVLNode, IVLNode, IHasCommands, IHa
     private ImmutableArray<BusInfo> audioInputBusses, audioOutputBusses, eventInputBusses, eventOutputBusses;
     private readonly ProcessSetup processSetup;
     private readonly AudioOutput audioOutput;
-    private readonly StatePin statePin;
+    private readonly Pin<IChannel<PluginState>> statePin;
 
     internal EffectHost(NodeContext nodeContext, EffectNodeInfo info) : base(nodeContext)
     {
@@ -137,16 +137,15 @@ internal EffectHost(NodeContext nodeContext, EffectNodeInfo info) : base(nodeCon
 
         var i = 0; var o = 0;
 
-        inputs[i] = statePin = new StatePin();
-        i++;
-        inputs[i++] = boundsPin = new Pin<IChannel<RectangleF>>();
-        inputs[i++] = audioInputPin = new AudioPin();
+        inputs[i++] = statePin = new Pin<IChannel<PluginState>>();
+        inputs[i++] = windowStatePin = new Pin<IChannel<WindowState>>();
+        inputs[i++] = audioInputPin = new Pin<IReadOnlyList<AudioSignal>>();
         inputs[i++] = midiInputPin = new Pin<IObservable<IMidiMessage>>();
         inputs[i++] = parametersPin = new Pin<Dictionary<string, object>>();
         inputs[i++] = applyPin = new Pin<bool>();
 
         outputs[o++] = new Pin<EffectHost>() { Value = this };
-        outputs[o++] = audioOutputPin = new AudioPin();
+        outputs[o++] = audioOutputPin = new Pin<IReadOnlyList<AudioSignal>>();
         outputs[o++] = midiOutputPin = new Pin<IObservable<IMidiMessage>>() 
         { 
             Value = outputEvents.ObserveOn(Scheduler.Default).SelectMany(e => TryTranslateToMidi(in e, out var m) ? new[] { m } : [])
@@ -279,10 +278,12 @@ void IVLNode.Update()
             }
         }
 
-        if (Acknowledge(ref bounds, boundsPin.Value?.Value ?? RectangleF.Empty))
+        if (Acknowledge(ref windowState, windowStatePin.Value?.Value))
         {
-            if (!bounds.IsEmpty)
-                SetWindowBounds(bounds);
+            if (windowState is null || windowState.IsVisible)
+                ShowUI(windowState?.Bounds, windowState?.Visibility.ToFormWindowState(), trackWindowState: true);
+            else
+                HideUI();
         }
 
         if (Acknowledge(ref apply, applyPin.Value))
@@ -460,7 +461,15 @@ void IComponentHandler2.finishGroupEdit()
     {
         get
         {
-            yield return ("Show UI", Command.Create(ShowUI).ExecuteOn(AppHost.SynchronizationContext));
+            yield return ("Show UI", Command.Create(
+                () =>
+                {
+                    var formWindowState = System.Windows.Forms.FormWindowState.Normal;
+                    if (windowState != null && windowState.Visibility >= WindowVisibility.Normal)
+                        formWindowState = windowState.Visibility.ToFormWindowState();
+                    ShowUI(windowState?.Bounds, formWindowState, trackWindowState: true);
+                })
+                .ExecuteOn(AppHost.SynchronizationContext));
         }
     }
 

src/Internal/Startup.cs

@@ -96,7 +96,7 @@ IVLNodeDescription GetNodeDescription(IVLNodeDescriptionFactory nodeDescriptionF
             var inputs = new List<IVLPinDescription>()
             {
                 new PinDescription(EffectHost.StateInputPinName, typeof(IChannel<PluginState>)) { IsVisible = false },
-                new PinDescription(EffectHost.BoundsInputPinName, typeof(IChannel<RectangleF>)) { IsVisible = false },
+                new PinDescription(EffectHost.WindowStatePinName, typeof(IChannel<WindowState>)) { IsVisible = false },
                 new PinDescription("Audio In", typeof(IEnumerable<AudioSignal>)),
                 new PinDescription("Midi In", typeof(IObservable<IMidiMessage>)),
                 new PinDescription("Parameters", typeof(Dictionary<string, object>)) { PinGroupKind = PinGroupKind.Dictionary },

src/PluginState.cs

@@ -1,11 +1,13 @@
 using System.Collections.Immutable;
 using System.Runtime.CompilerServices;
 using VL.Core;
+using VL.Core.CompilerServices;
 using VST3;
 using VST3.Hosting;
 
 namespace VL.Audio.VST;
 
+[Smell(SymbolSmell.Advanced)]
 public sealed record PluginState(Guid Id, ImmutableArray<byte> Component, ImmutableArray<byte> Controller)
 {
     public static readonly PluginState Default = new PluginState(default, ImmutableArray<byte>.Empty, ImmutableArray<byte>.Empty);

src/VL.Audio.VST.csproj

@@ -9,6 +9,9 @@
     <OutputPath>..\lib</OutputPath>
     <PackageRepositories>$([System.IO.Path]::GetFullPath($(MsBuildThisFileDirectory)..\..));$([System.IO.Path]::GetFullPath($(MsBuildThisFileDirectory)..\..\VL.Audio))</PackageRepositories>
     <RestoreAdditionalProjectSources>https://teamcity.vvvv.org/guestAuth/app/nuget/feed/_Root/default/v3/index.json</RestoreAdditionalProjectSources>
+
+    <GenerateDocumentationFile>true</GenerateDocumentationFile>
+    <NoWarn>CS1591</NoWarn>
   </PropertyGroup>
 
   <ItemGroup>
@@ -23,6 +26,8 @@
     <PackageReference Include="VL.Audio" Version="1.9.3" />
     <PackageReference Include="VL.Core.Commands" Version="2024.6.7-0282-gb45ecfaff4" />
     <PackageReference Include="VL.CoreLib" Version="2024.6.7-0282-gb45ecfaff4" />
+    <!-- TODO: Needed to place symbols in Advanced category - should be moved to core -->
+    <PackageReference Include="VL.AppServices" Version="2024.6.7-0282-gb45ecfaff4" />
     <PackageReference Include="VL.IO.Midi" Version="1.1.1" />
   </ItemGroup>