The Task returned from CompositionDrawingSurface.UpdateWithKeyedMutexAsync never complete

[martinrhan]

I am trying to use DirectX11 in my Avalonia application. I used Vortice for the API bindings. The following is my code.

public partial class MainWindow : Window {
    static IDXGIFactory7 DXGIFactory = DXGI.CreateDXGIFactory1<IDXGIFactory7>();
    static ID2D1Factory D2D1Factory = D2D1.D2D1CreateFactory<ID2D1Factory>();


    public MainWindow() {
        InitializeComponent();

        int imageWidth = 1024;
        int imageHeight = 1024;

        ID3D11Device3 device_d3d11 = D3D11.D3D11CreateDevice(DriverType.Hardware, DeviceCreationFlags.BgraSupport, Vortice.Direct3D.FeatureLevel.Level_11_1).QueryInterface<ID3D11Device3>();
        
        ID3D11Texture2D texture = device_d3d11.CreateTexture2D1(new() {
            Format = Format.R8G8B8A8_UNorm,
            Width = (uint)imageWidth,
            Height = (uint)imageHeight,
            ArraySize = 1,
            MipLevels = 1,
            SampleDescription = SampleDescription.Default,
            BindFlags = BindFlags.RenderTarget,
            Usage = ResourceUsage.Default,
            CPUAccessFlags = CpuAccessFlags.None,
            MiscFlags = ResourceOptionFlags.SharedNTHandle | ResourceOptionFlags.SharedKeyedMutex,
            TextureLayout = TextureLayout.Undefined
        });

        IDXGIDevice device_dxgi = device_d3d11.QueryInterface<IDXGIDevice>();

        ID2D1RenderTarget renderTarget = D2D1Factory.CreateDxgiSurfaceRenderTarget(
            texture.QueryInterface<IDXGISurface>(),
            new() {
                Type = RenderTargetType.Hardware,
                PixelFormat = new(Format.R8G8B8A8_UNorm, Vortice.DCommon.AlphaMode.Ignore),
                Usage = RenderTargetUsage.None,
                MinLevel = Vortice.Direct2D1.FeatureLevel.Default,
                DpiX = 0,
                DpiY = 0
            }
            );

        RawRectF rect = new(10,10,100,100);
        ID2D1Brush brush = renderTarget.CreateSolidColorBrush(new(0xFF0000FF));
        renderTarget.DrawRectangle(rect, brush);

        IDXGIResource1 dxgiResource1 = texture.QueryInterface<IDXGIResource1>();
        IDXGIKeyedMutex mutex = dxgiResource1.QueryInterface<IDXGIKeyedMutex>();
        mutex.AcquireSync(0, 100000);
        IntPtr ptr = dxgiResource1.CreateSharedHandle(null, Vortice.DXGI.SharedResourceFlags.Read, null);
        PlatformHandle platformHandle = new(ptr, null);

        Compositor? compositor = Compositor.TryGetDefaultCompositor();
        if (compositor is null) return;
        var task = compositor.TryGetCompositionGpuInterop();
        ICompositionGpuInterop? gpuInterop = task.Result;
        if (gpuInterop is null) return;
        ICompositionImportedGpuImage importedImage = gpuInterop.ImportImage(
            platformHandle,
            new() {
                Format = PlatformGraphicsExternalImageFormat.R8G8B8A8UNorm,
                Width = imageWidth,
                Height = imageHeight,
                MemoryOffset = 0,
                MemorySize = (ulong)(imageWidth * imageHeight * sizeof(uint)),
                TopLeftOrigin = true
            }
            );

        CompositionSurfaceVisual visual = compositor.CreateSurfaceVisual();
        CompositionDrawingSurface surface_conpositionDrawing = compositor.CreateDrawingSurface();
        visual.Surface = surface_conpositionDrawing;
        surface_conpositionDrawing.UpdateWithKeyedMutexAsync(importedImage, 0, 0).Wait();//The problem occurs at here

        ElementComposition.SetElementChildVisual(this, visual);//This line of code is never reached 
        this.InvalidateVisual();
    }
}

[kekekeks]

You aren't supposed to call Task.Wait() on the UI thread, that will cause a deadlock. If any Avalonia API returns you a task you need to asynchronously wait for completion.

[martinrhan]

Thank you for your comment. I removed the .Wait() and it is still now working.
The Debug console shows two red lines colored text:

Exception thrown: 'System.NotSupportedException' in Avalonia.Win32.dll
Exception thrown: 'Avalonia.Platform.PlatformGraphicsContextLostException' in Avalonia.Base.dll

However, the IDE did not break on these exceptions.

[martinrhan]

I solved it by adding the description string KnownPlatformGraphicsExternalImageHandleTypes.D3D11TextureNtHandle into the PlatformHandle.
The window showed up without any exception. However it is blank, the ID3D11Texture2D isn't showed in the window.