Merge branch 'master' into context-menu-page-in-control-catalog

appveyor.yml

@@ -15,6 +15,7 @@ environment:
   MYGET_API_URL: https://www.myget.org/F/avalonia-ci/api/v2/package
 init:
 - ps: (New-Object Net.WebClient).DownloadFile('https://raw.githubusercontent.com/appveyor/ci/master/scripts/xamarin-vs2017-151-fixed.targets', "C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\MSBuild\15.0\Microsoft.Common.Targets\ImportAfter\Xamarin.Common.targets")
+- ps: if (Test-Path env:nuget_address) {[System.IO.File]::AppendAllText("C:\Windows\System32\drivers\etc\hosts", "`n$($env:nuget_address)`tapi.nuget.org")}
 install:
   - if not exist gtk-sharp-2.12.26.msi appveyor DownloadFile http://download.xamarin.com/GTKforWindows/Windows/gtk-sharp-2.12.26.msi
   - if not exist dotnet-1.0.1.exe appveyor DownloadFile https://go.microsoft.com/fwlink/?linkid=843448 -FileName "dotnet-1.0.1.exe"

build/Base.props

@@ -0,0 +1,5 @@
+<Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <ItemGroup>
+    <PackageReference Include="System.ValueTuple" Version="4.3.1" />
+  </ItemGroup>
+</Project>

build/SharpDX.props

@@ -3,6 +3,7 @@
     <PackageReference Include="SharpDX" Version="3.1.1" />
     <PackageReference Include="SharpDX.Direct2D1" Version="3.1.1" />
     <PackageReference Include="SharpDX.Direct3D11" Version="3.1.1" />
+    <PackageReference Include="SharpDX.Direct3D9" Version="3.1.1" Condition="'$(UseDirect3D9)' == 'true'" />
     <PackageReference Include="SharpDX.DXGI" Version="3.1.1" />
   </ItemGroup>
 </Project>

packages.cake

@@ -75,22 +75,26 @@ public class Packages
         var SplatVersion = packageVersions["Splat"].FirstOrDefault().Item1;
         var SpracheVersion = packageVersions["Sprache"].FirstOrDefault().Item1;
         var SystemReactiveVersion = packageVersions["System.Reactive"].FirstOrDefault().Item1;
+        var SystemValueTupleVersion = packageVersions["System.ValueTuple"].FirstOrDefault().Item1;
         SkiaSharpVersion = packageVersions["SkiaSharp"].FirstOrDefault().Item1;
 		SkiaSharpLinuxVersion = packageVersions["Avalonia.Skia.Linux.Natives"].FirstOrDefault().Item1;
         var SharpDXVersion = packageVersions["SharpDX"].FirstOrDefault().Item1;
         var SharpDXDirect2D1Version = packageVersions["SharpDX.Direct2D1"].FirstOrDefault().Item1;
         var SharpDXDirect3D11Version = packageVersions["SharpDX.Direct3D11"].FirstOrDefault().Item1;
+        var SharpDXDirect3D9Version = packageVersions["SharpDX.Direct3D9"].FirstOrDefault().Item1;
         var SharpDXDXGIVersion = packageVersions["SharpDX.DXGI"].FirstOrDefault().Item1;
 
         context.Information("Package: Serilog, version: {0}", SerilogVersion);
         context.Information("Package: Splat, version: {0}", SplatVersion);
         context.Information("Package: Sprache, version: {0}", SpracheVersion);
         context.Information("Package: System.Reactive, version: {0}", SystemReactiveVersion);
+        context.Information("Package: System.ValueTuple, version: {0}", SystemValueTupleVersion);
         context.Information("Package: SkiaSharp, version: {0}", SkiaSharpVersion);
         context.Information("Package: Avalonia.Skia.Linux.Natives, version: {0}", SkiaSharpLinuxVersion);
         context.Information("Package: SharpDX, version: {0}", SharpDXVersion);
         context.Information("Package: SharpDX.Direct2D1, version: {0}", SharpDXDirect2D1Version);
         context.Information("Package: SharpDX.Direct3D11, version: {0}", SharpDXDirect3D11Version);
+        context.Information("Package: SharpDX.Direct3D9, version: {0}", SharpDXDirect3D9Version);
         context.Information("Package: SharpDX.DXGI, version: {0}", SharpDXDXGIVersion);
 
         var nugetPackagesDir = System.Environment.GetEnvironmentVariable("NUGET_HOME")
@@ -197,6 +201,7 @@ public class Packages
                     new NuSpecDependency() { Id = "Splat", Version = SplatVersion },
                     new NuSpecDependency() { Id = "Sprache", Version = SpracheVersion },
                     new NuSpecDependency() { Id = "System.Reactive", Version = SystemReactiveVersion },
+                    new NuSpecDependency() { Id = "System.ValueTuple", Version = SystemValueTupleVersion },
                     //.NET Core
                     new NuSpecDependency() { Id = "System.Threading.ThreadPool", TargetFramework = "netcoreapp1.0", Version = "4.3.0" },
                     new NuSpecDependency() { Id = "Microsoft.Extensions.DependencyModel", TargetFramework = "netcoreapp1.0", Version = "1.1.0" },
@@ -204,7 +209,8 @@ public class Packages
                     new NuSpecDependency() { Id = "Splat", TargetFramework = "netcoreapp1.0", Version = SplatVersion },
                     new NuSpecDependency() { Id = "Serilog", TargetFramework = "netcoreapp1.0", Version = SerilogVersion },
                     new NuSpecDependency() { Id = "Sprache", TargetFramework = "netcoreapp1.0", Version = SpracheVersion },
-                    new NuSpecDependency() { Id = "System.Reactive", TargetFramework = "netcoreapp1.0", Version = SystemReactiveVersion }
+                    new NuSpecDependency() { Id = "System.Reactive", TargetFramework = "netcoreapp1.0", Version = SystemReactiveVersion },
+                    new NuSpecDependency() { Id = "System.ValueTuple", TargetFramework = "netcoreapp1.0", Version = SystemValueTupleVersion }
                 },
                 Files = coreLibrariesNuSpecContent
                     .Concat(win32CoreLibrariesNuSpecContent).Concat(net45RuntimePlatform)
@@ -472,6 +478,7 @@ public class Packages
                 {
                     new NuSpecDependency() { Id = "Avalonia.Win32", Version = parameters.Version },
                     new NuSpecDependency() { Id = "Avalonia.Direct2D1", Version = parameters.Version },
+                    new NuSpecDependency() { Id = "SharpDX.Direct3D9", Version = SharpDXDirect3D9Version },
                 },
                 Files = new []
                 {

samples/interop/WindowsInteropTest/Program.cs

@@ -15,7 +15,7 @@ namespace WindowsInteropTest
         {
             System.Windows.Forms.Application.EnableVisualStyles();
             System.Windows.Forms.Application.SetCompatibleTextRenderingDefault(false);
-            AppBuilder.Configure<App>().UseWin32().UseSkia().SetupWithoutStarting();
+            AppBuilder.Configure<App>().UseWin32().UseDirect2D1().SetupWithoutStarting();
             System.Windows.Forms.Application.Run(new SelectorForm());
         }
     }

src/Avalonia.Base/Avalonia.Base.csproj

@@ -30,6 +30,7 @@
       <Link>Properties\SharedAssemblyInfo.cs</Link>
     </Compile>
   </ItemGroup>
+  <Import Project="..\..\build\Base.props" />
   <Import Project="..\..\build\Rx.props" />
   <Import Project="..\..\build\JetBrains.Annotations.props" />
 </Project>

src/Avalonia.Controls/TextBox.cs

@@ -236,6 +236,11 @@ namespace Avalonia.Controls
         {
             _presenter = e.NameScope.Get<TextPresenter>("PART_TextPresenter");
             _presenter.Cursor = new Cursor(StandardCursorType.Ibeam);
+
+            if(IsFocused)
+            {
+                _presenter.ShowCaret();
+            }
         }
 
         protected override void OnGotFocus(GotFocusEventArgs e)
@@ -254,7 +259,7 @@ namespace Avalonia.Controls
             }
             else
             {
-                _presenter.ShowCaret();
+                _presenter?.ShowCaret();
             }
         }
 
@@ -263,7 +268,7 @@ namespace Avalonia.Controls
             base.OnLostFocus(e);
             SelectionStart = 0;
             SelectionEnd = 0;
-            _presenter.HideCaret();
+            _presenter?.HideCaret();
         }
 
         protected override void OnTextInput(TextInputEventArgs e)

src/Avalonia.Controls/ToolTip.cs

@@ -106,24 +106,28 @@ namespace Avalonia.Controls
             if (control != null && control.IsVisible && control.GetVisualRoot() != null)
             {
                 var cp = (control.GetVisualRoot() as IInputRoot)?.MouseDevice?.GetPosition(control);
-                var position = control.PointToScreen(cp ?? new Point(0, 0)) + new Vector(0, 22);
 
-                if (s_popup == null)
+                if (cp.HasValue && control.IsVisible && new Rect(control.Bounds.Size).Contains(cp.Value))
                 {
-                    s_popup = new PopupRoot();
-                    s_popup.Content = new ToolTip();
-                }
-                else
-                {
-                    ((ISetLogicalParent)s_popup).SetParent(null);
-                }
+                    var position = control.PointToScreen(cp.Value) + new Vector(0, 22);
+
+                    if (s_popup == null)
+                    {
+                        s_popup = new PopupRoot();
+                        s_popup.Content = new ToolTip();
+                    }
+                    else
+                    {
+                        ((ISetLogicalParent)s_popup).SetParent(null);
+                    }
 
                 ((ISetLogicalParent)s_popup).SetParent(control);
-                ((ToolTip)s_popup.Content).Content = GetTip(control);
-                s_popup.Position = position;
-                s_popup.Show();
+                    ((ToolTip)s_popup.Content).Content = GetTip(control);
+                    s_popup.Position = position;
+                    s_popup.Show();
 
-                s_current = control;
+                    s_current = control;
+                }
             }
         }
 

src/Avalonia.Input/Avalonia.Input.csproj

@@ -37,8 +37,5 @@
       <Link>Properties\SharedAssemblyInfo.cs</Link>
     </Compile>
   </ItemGroup>
-  <ItemGroup>
-    <PackageReference Include="System.ValueTuple" Version="4.3.1" />
-  </ItemGroup>
   <Import Project="..\..\build\Rx.props" />
 </Project>

src/Skia/Avalonia.Skia/DrawingContextImpl.cs

@@ -141,23 +141,17 @@ namespace Avalonia.Skia
             var rv = new PaintWrapper(paint);
             paint.IsStroke = false;
 
-            // TODO: SkiaSharp does not contain alpha yet!
+            
             double opacity = brush.Opacity * _currentOpacity;
-            //paint.SetAlpha(paint.GetAlpha() * opacity);
             paint.IsAntialias = true;
 
-            SKColor color = new SKColor(255, 255, 255, 255);
-
             var solid = brush as ISolidColorBrush;
-            if (solid != null)
-                color = solid.Color.ToSKColor();
-
-            paint.Color = (new SKColor(color.Red, color.Green, color.Blue, (byte)(color.Alpha * opacity)));
-
             if (solid != null)
             {
+                paint.Color = new SKColor(solid.Color.R, solid.Color.G, solid.Color.B, (byte) (solid.Color.A * opacity));
                 return rv;
             }
+            paint.Color = (new SKColor(255, 255, 255, (byte)(255 * opacity)));
 
             var gradient = brush as IGradientBrush;
             if (gradient != null)

src/Skia/Avalonia.Skia/FormattedTextImpl.cs

@@ -42,7 +42,6 @@ namespace Avalonia.Skia
             _paint.Typeface = skiaTypeface;
             _paint.TextSize = (float)(typeface?.FontSize ?? 12);
             _paint.TextAlign = textAlignment.ToSKTextAlign();
-            _paint.BlendMode = SKBlendMode.Src;
 
             _wrapping = wrapping;
             _constraint = constraint;
@@ -200,66 +199,65 @@ namespace Avalonia.Skia
                 }
                 ctx->Canvas->restore();
             */
-            SKPaint paint = _paint;
-            IDisposable currd = null;
-            var currentWrapper = foreground;
-
-            try
+            using (var paint = _paint.Clone())
             {
-                SKPaint currFGPaint = ApplyWrapperTo(ref foreground, ref currd, paint);
-                bool hasCusomFGBrushes = _foregroundBrushes.Any();
-
-                for (int c = 0; c < _skiaLines.Count; c++)
+                IDisposable currd = null;
+                var currentWrapper = foreground;
+                SKPaint currentPaint = null;
+                try
                 {
-                    AvaloniaFormattedTextLine line = _skiaLines[c];
-
-                    float x = TransformX(origin.X, 0, paint.TextAlign);
+                    ApplyWrapperTo(ref currentPaint, foreground, ref currd, paint);
+                    bool hasCusomFGBrushes = _foregroundBrushes.Any();
 
-                    if (!hasCusomFGBrushes)
-                    {
-                        var subString = Text.Substring(line.Start, line.Length);
-                        canvas.DrawText(subString, x, origin.Y + line.Top + _lineOffset, paint);
-                    }
-                    else
+                    for (int c = 0; c < _skiaLines.Count; c++)
                     {
-                        float currX = x;
-                        string subStr;
-                        int len;
+                        AvaloniaFormattedTextLine line = _skiaLines[c];
 
-                        for (int i = line.Start; i < line.Start + line.Length;)
-                        {
-                            var fb = GetNextForegroundBrush(ref line, i, out len);
-
-                            if (fb != null)
-                            {
-                                //TODO: figure out how to get the brush size
-                                currentWrapper = context.CreatePaint(fb, new Size());
-                            }
-                            else
-                            {
-                                if (!currentWrapper.Equals(foreground)) currentWrapper.Dispose();
-                                currentWrapper = foreground;
-                            }
+                        float x = TransformX(origin.X, 0, paint.TextAlign);
 
-                            subStr = Text.Substring(i, len);
+                        if (!hasCusomFGBrushes)
+                        {
+                            var subString = Text.Substring(line.Start, line.Length);
+                            canvas.DrawText(subString, x, origin.Y + line.Top + _lineOffset, paint);
+                        }
+                        else
+                        {
+                            float currX = x;
+                            string subStr;
+                            int len;
 
-                            if (currFGPaint != currentWrapper.Paint)
+                            for (int i = line.Start; i < line.Start + line.Length;)
                             {
-                                currFGPaint = ApplyWrapperTo(ref currentWrapper, ref currd, paint);
+                                var fb = GetNextForegroundBrush(ref line, i, out len);
+
+                                if (fb != null)
+                                {
+                                    //TODO: figure out how to get the brush size
+                                    currentWrapper = context.CreatePaint(fb, new Size());
+                                }
+                                else
+                                {
+                                    if (!currentWrapper.Equals(foreground)) currentWrapper.Dispose();
+                                    currentWrapper = foreground;
+                                }
+
+                                subStr = Text.Substring(i, len);
+
+                                ApplyWrapperTo(ref currentPaint, currentWrapper, ref currd, paint);
+                                
+                                canvas.DrawText(subStr, currX, origin.Y + line.Top + _lineOffset, paint);
+
+                                i += len;
+                                currX += paint.MeasureText(subStr);
                             }
-
-                            canvas.DrawText(subStr, currX, origin.Y + line.Top + _lineOffset, paint);
-
-                            i += len;
-                            currX += paint.MeasureText(subStr);
                         }
                     }
                 }
-            }
-            finally
-            {
-                if (!currentWrapper.Equals(foreground)) currentWrapper.Dispose();
-                currd?.Dispose();
+                finally
+                {
+                    if (!currentWrapper.Equals(foreground)) currentWrapper.Dispose();
+                    currd?.Dispose();
+                }
             }
         }
 
@@ -278,12 +276,13 @@ namespace Avalonia.Skia
         private Size _size;
         private List<AvaloniaFormattedTextLine> _skiaLines;
 
-        private static SKPaint ApplyWrapperTo(ref DrawingContextImpl.PaintWrapper wrapper,
+        private static void ApplyWrapperTo(ref SKPaint current, DrawingContextImpl.PaintWrapper wrapper,
                                                 ref IDisposable curr, SKPaint paint)
         {
+            if (current == wrapper.Paint)
+                return;
             curr?.Dispose();
             curr = wrapper.ApplyTo(paint);
-            return wrapper.Paint;
         }
 
         private static bool IsBreakChar(char c)

src/Windows/Avalonia.Direct2D1/ExternalRenderTarget.cs

@@ -15,7 +15,6 @@ namespace Avalonia.Direct2D1
     {
         private readonly IExternalDirect2DRenderTargetSurface _externalRenderTargetProvider;
         private readonly DirectWriteFactory _dwFactory;
-        private SharpDX.Direct2D1.RenderTarget _target;
         public ExternalRenderTarget(IExternalDirect2DRenderTargetSurface externalRenderTargetProvider,
             DirectWriteFactory dwFactory)
         {
@@ -25,15 +24,14 @@ namespace Avalonia.Direct2D1
 
         public void Dispose()
         {
-            _target?.Dispose();
-            _target = null;
+            _externalRenderTargetProvider.DestroyRenderTarget();
         }
 
         public IDrawingContextImpl CreateDrawingContext(IVisualBrushRenderer visualBrushRenderer)
         {
-            _target = _target ?? _externalRenderTargetProvider.CreateRenderTarget();
+            var target =  _externalRenderTargetProvider.GetOrCreateRenderTarget();
             _externalRenderTargetProvider.BeforeDrawing();
-            return new DrawingContextImpl(visualBrushRenderer, _target, _dwFactory, null, () =>
+            return new DrawingContextImpl(visualBrushRenderer, target, _dwFactory, null, () =>
             {
                 try
                 {
@@ -41,8 +39,7 @@ namespace Avalonia.Direct2D1
                 }
                 catch (SharpDXException ex) when ((uint) ex.HResult == 0x8899000C) // D2DERR_RECREATE_TARGET
                 {
-                    _target?.Dispose();
-                    _target = null;
+                    _externalRenderTargetProvider.DestroyRenderTarget();
                 }
             });
         }

src/Windows/Avalonia.Direct2D1/IExternalDirect2DRenderTargetSurface.cs

@@ -8,7 +8,8 @@ namespace Avalonia.Direct2D1
 {
     public interface IExternalDirect2DRenderTargetSurface
     {
-        SharpDX.Direct2D1.RenderTarget CreateRenderTarget();
+        SharpDX.Direct2D1.RenderTarget GetOrCreateRenderTarget();
+        void DestroyRenderTarget();
         void BeforeDrawing();
         void AfterDrawing();
     }

src/Windows/Avalonia.Win32.Interop/Avalonia.Win32.Interop.csproj

@@ -49,6 +49,8 @@
     </Compile>
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="Wpf\CursorShim.cs" />
+    <Compile Include="Wpf\Direct2DImageSurface.cs" />
+    <Compile Include="Wpf\IntSize.cs" />
     <Compile Include="Wpf\WpfInteropExtensions.cs" />
     <Compile Include="Wpf\WpfAvaloniaHost.cs" />
     <Compile Include="Wpf\WpfMouseDevice.cs" />
@@ -104,10 +106,18 @@
       <Project>{6417e941-21bc-467b-a771-0de389353ce6}</Project>
       <Name>Avalonia.Markup</Name>
     </ProjectReference>
+    <ProjectReference Include="..\Avalonia.Direct2D1\Avalonia.Direct2D1.csproj">
+      <Project>{3e908f67-5543-4879-a1dc-08eace79b3cd}</Project>
+      <Name>Avalonia.Direct2D1</Name>
+    </ProjectReference>
     <ProjectReference Include="..\Avalonia.Win32\Avalonia.Win32.csproj">
       <Project>{811a76cf-1cf6-440f-963b-bbe31bd72a82}</Project>
       <Name>Avalonia.Win32</Name>
     </ProjectReference>
   </ItemGroup>
+  <PropertyGroup>
+    <UseDirect3D9>true</UseDirect3D9>
+  </PropertyGroup>
+  <Import Project="..\..\..\build\SharpDX.props" />
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
 </Project>

src/Windows/Avalonia.Win32.Interop/Wpf/Direct2DImageSurface.cs

@@ -0,0 +1,208 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Runtime.InteropServices;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows;
+using System.Windows.Interop;
+using Avalonia.Direct2D1;
+using SharpDX;
+using SharpDX.Direct2D1;
+using SharpDX.Direct3D11;
+using SharpDX.Direct3D9;
+using SharpDX.DXGI;
+using AlphaMode = SharpDX.Direct2D1.AlphaMode;
+using Device = SharpDX.Direct3D11.Device;
+using Format = SharpDX.DXGI.Format;
+using MapFlags = SharpDX.Direct3D11.MapFlags;
+using PresentParameters = SharpDX.DXGI.PresentParameters;
+using Query = SharpDX.Direct3D11.Query;
+using QueryType = SharpDX.Direct3D11.QueryType;
+using RenderTarget = SharpDX.Direct2D1.RenderTarget;
+using Surface = SharpDX.DXGI.Surface;
+using SwapEffect = SharpDX.DXGI.SwapEffect;
+using Usage = SharpDX.Direct3D9.Usage;
+
+namespace Avalonia.Win32.Interop.Wpf
+{
+    class Direct2DImageSurface : IExternalDirect2DRenderTargetSurface, IDisposable
+    {
+        class SwapBuffer: IDisposable
+        {
+            private readonly Query _event;
+            private readonly SharpDX.Direct3D11.Resource _resource;
+            private readonly SharpDX.Direct3D11.Resource _sharedResource;
+            public SharpDX.Direct3D9.Surface Texture { get; }
+            public RenderTarget Target { get;}
+            public IntSize Size { get; }
+
+            public SwapBuffer(IntSize size, Vector dpi)
+            {
+                int width = (int) size.Width;
+                int height = (int) size.Height;
+                _event = new Query(s_dxDevice, new QueryDescription {Type = QueryType.Event});
+                using (var texture = new Texture2D(s_dxDevice, new Texture2DDescription
+                {
+                    Width = width,
+                    Height = height,
+                    ArraySize = 1,
+                    MipLevels = 1,
+                    Format = Format.B8G8R8A8_UNorm,
+                    Usage = ResourceUsage.Default,
+                    SampleDescription = new SampleDescription(2, 0),
+                    BindFlags = BindFlags.RenderTarget,
+                }))
+                using (var surface = texture.QueryInterface<Surface>())
+                
+                {
+                    _resource = texture.QueryInterface<SharpDX.Direct3D11.Resource>();
+                    
+                    Target = new RenderTarget(AvaloniaLocator.Current.GetService<SharpDX.Direct2D1.Factory>(), surface,
+                        new RenderTargetProperties
+                        {
+                            DpiX = (float) dpi.X,
+                            DpiY = (float) dpi.Y,
+                            MinLevel = FeatureLevel.Level_10,
+                            PixelFormat = new PixelFormat(Format.B8G8R8A8_UNorm, AlphaMode.Premultiplied),
+
+                        });
+                }
+                using (var texture = new Texture2D(s_dxDevice, new Texture2DDescription
+                {
+                    Width = width,
+                    Height = height,
+                    ArraySize = 1,
+                    MipLevels = 1,
+                    Format = Format.B8G8R8A8_UNorm,
+                    Usage = ResourceUsage.Default,
+                    SampleDescription = new SampleDescription(1, 0),
+                    BindFlags = BindFlags.RenderTarget|BindFlags.ShaderResource,
+                    OptionFlags = ResourceOptionFlags.Shared,
+                }))
+                using (var resource = texture.QueryInterface<SharpDX.DXGI.Resource>())
+                {
+                    _sharedResource = texture.QueryInterface<SharpDX.Direct3D11.Resource>();
+                    var handle = resource.SharedHandle;
+                    using (var texture9 = new Texture(s_d3DDevice, texture.Description.Width,
+                        texture.Description.Height, 1,
+                        Usage.RenderTarget, SharpDX.Direct3D9.Format.A8R8G8B8, Pool.Default, ref handle))
+                        Texture = texture9.GetSurfaceLevel(0);
+                }
+                Size = size;
+            }
+
+            public void Dispose()
+            {
+                Texture?.Dispose();
+                Target?.Dispose();
+                _resource?.Dispose();
+                _sharedResource?.Dispose();
+                _event?.Dispose();
+            }
+
+            public void Flush()
+            {
+                s_dxDevice.ImmediateContext.ResolveSubresource(_resource, 0, _sharedResource, 0, Format.B8G8R8A8_UNorm);
+                s_dxDevice.ImmediateContext.Flush();
+                s_dxDevice.ImmediateContext.End(_event);
+                s_dxDevice.ImmediateContext.GetData(_event).Dispose();
+            }
+        }
+
+        private D3DImage _image;
+        private SwapBuffer _backBuffer;
+        private readonly WpfTopLevelImpl _impl;
+        private static Device s_dxDevice;
+        private static Direct3DEx s_d3DContext;
+        private static DeviceEx s_d3DDevice;
+        private Vector _oldDpi;
+
+
+        [DllImport("user32.dll", SetLastError = false)]
+        private static extern IntPtr GetDesktopWindow();
+        void EnsureDirectX()
+        {
+            if(s_d3DDevice != null)
+                return;
+            s_d3DContext = new Direct3DEx();
+
+            SharpDX.Direct3D9.PresentParameters presentparams = new SharpDX.Direct3D9.PresentParameters
+            {
+                Windowed = true,
+                SwapEffect = SharpDX.Direct3D9.SwapEffect.Discard,
+                DeviceWindowHandle = GetDesktopWindow(),
+                PresentationInterval = PresentInterval.Default
+            };
+            s_dxDevice = s_dxDevice ?? AvaloniaLocator.Current.GetService<SharpDX.DXGI.Device>()
+                             .QueryInterface<SharpDX.Direct3D11.Device>();
+            s_d3DDevice = new DeviceEx(s_d3DContext, 0, DeviceType.Hardware, IntPtr.Zero, CreateFlags.HardwareVertexProcessing | CreateFlags.Multithreaded | CreateFlags.FpuPreserve, presentparams);
+
+        }
+
+        public Direct2DImageSurface(WpfTopLevelImpl impl)
+        {
+            _impl = impl;
+        }
+
+        public RenderTarget GetOrCreateRenderTarget()
+        {
+            EnsureDirectX();
+            var scale = _impl.GetScaling();
+            var size = new IntSize(_impl.ActualWidth * scale.X, _impl.ActualHeight * scale.Y);
+            var dpi = scale * 96;
+
+            if (_backBuffer!=null && _backBuffer.Size == size)
+                return _backBuffer.Target;
+
+            if (_image == null || _oldDpi.X != dpi.X || _oldDpi.Y != dpi.Y)
+            {
+                _image = new D3DImage(dpi.X, dpi.Y);
+            }
+            _impl.ImageSource = _image;
+            
+            RemoveAndDispose(ref _backBuffer);
+            if (size == default(IntSize))
+            {
+                _image.Lock();
+                _image.SetBackBuffer(D3DResourceType.IDirect3DSurface9, IntPtr.Zero);
+                _image.Unlock();
+                return null;
+            }
+            _backBuffer = new SwapBuffer(size, dpi);
+
+            return _backBuffer.Target;
+        }
+
+        void RemoveAndDispose<T>(ref T d) where T : IDisposable
+        {
+            d?.Dispose();
+            d = default(T);
+        }
+
+        void Swap()
+        {
+            _backBuffer.Flush();
+            _image.Lock();
+            _image.SetBackBuffer(D3DResourceType.IDirect3DSurface9, _backBuffer?.Texture?.NativePointer ?? IntPtr.Zero, true);
+            _image.AddDirtyRect(new Int32Rect(0, 0, _image.PixelWidth, _image.PixelHeight));
+            _image.Unlock();
+        }
+
+        public void DestroyRenderTarget()
+        {
+            RemoveAndDispose(ref _backBuffer);
+        }
+
+        public void BeforeDrawing()
+        {
+            
+        }
+
+        public void AfterDrawing() => Swap();
+        public void Dispose()
+        {
+            RemoveAndDispose(ref _backBuffer);
+        }
+    }
+}

src/Windows/Avalonia.Win32.Interop/Wpf/IntSize.cs

@@ -0,0 +1,59 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Avalonia.Win32.Interop.Wpf
+{
+    struct IntSize : IEquatable<IntSize>
+    {
+        public bool Equals(IntSize other)
+        {
+            return Width == other.Width && Height == other.Height;
+        }
+
+        public IntSize(int width, int height)
+        {
+            Width = width;
+            Height = height;
+        }
+
+        public IntSize(double width, double height) : this((int) width, (int) height)
+        {
+            
+        }
+
+        public static implicit  operator IntSize(System.Windows.Size size)
+        {
+            return new IntSize {Width = (int) size.Width, Height = (int) size.Height};
+        }
+
+        public override bool Equals(object obj)
+        {
+            if (ReferenceEquals(null, obj)) return false;
+            return obj is IntSize && Equals((IntSize) obj);
+        }
+
+        public override int GetHashCode()
+        {
+            unchecked
+            {
+                return (Width * 397) ^ Height;
+            }
+        }
+
+        public static bool operator ==(IntSize left, IntSize right)
+        {
+            return left.Equals(right);
+        }
+
+        public static bool operator !=(IntSize left, IntSize right)
+        {
+            return !left.Equals(right);
+        }
+
+        public int Width { get; set; }
+        public int Height { get; set; }
+    }
+}

src/Windows/Avalonia.Win32.Interop/Wpf/WpfAvaloniaHost.cs

@@ -21,15 +21,32 @@ namespace Avalonia.Win32.Interop.Wpf
     {
         private WpfTopLevelImpl _impl;
         private readonly SynchronizationContext _sync;
+        private bool _hasChildren;
         public WpfAvaloniaHost()
         {
             _sync = SynchronizationContext.Current;
             _impl = new WpfTopLevelImpl();
             _impl.ControlRoot.Prepare();
             _impl.Visibility = Visibility.Visible;
-            AddLogicalChild(_impl);
-            AddVisualChild(_impl);
             SnapsToDevicePixels = true;
+            UseLayoutRounding = true;
+            PresentationSource.AddSourceChangedHandler(this, OnSourceChanged);
+        }
+
+        private void OnSourceChanged(object sender, SourceChangedEventArgs e)
+        {
+            if (e.NewSource != null && !_hasChildren)
+            {
+                AddLogicalChild(_impl);
+                AddVisualChild(_impl);
+                _hasChildren = true;
+            }
+            else
+            {
+                RemoveVisualChild(_impl);
+                RemoveLogicalChild(_impl);
+                _hasChildren = false;
+            }
         }
 
         public object Content

src/Windows/Avalonia.Win32.Interop/Wpf/WpfTopLevelImpl.cs

@@ -60,7 +60,7 @@ namespace Avalonia.Win32.Interop.Wpf
             PresentationSource.AddSourceChangedHandler(this, OnSourceChanged);
             _hook = WndProc;
             _ttl = this;
-            _surfaces = new object[] {new WritableBitmapSurface(this)};
+            _surfaces = new object[] {new WritableBitmapSurface(this), new Direct2DImageSurface(this)};
             _mouse = new WpfMouseDevice(this);
             _keyboard = AvaloniaLocator.Current.GetService<IKeyboardDevice>();
 
@@ -88,7 +88,12 @@ namespace Avalonia.Win32.Interop.Wpf
             _ttl.ScalingChanged?.Invoke(_ttl.Scaling);
         }
 
-        public void Dispose() => _ttl.Closed?.Invoke();
+        public void Dispose()
+        {
+            _ttl.Closed?.Invoke();
+            foreach(var d in _surfaces.OfType<IDisposable>())
+                d.Dispose();
+        }
 
         Size ITopLevelImpl.ClientSize => _finalSize;
         IMouseDevice ITopLevelImpl.MouseDevice => _mouse;
@@ -224,6 +229,13 @@ namespace Avalonia.Win32.Interop.Wpf
         Action<double> ITopLevelImpl.ScalingChanged { get; set; }
         Action ITopLevelImpl.Closed { get; set; }
         public new event Action LostFocus;
-        
+
+        internal Vector GetScaling()
+        {
+            var src = PresentationSource.FromVisual(this)?.CompositionTarget;
+            if (src == null)
+                return new Vector(1, 1);
+            return new Vector(src.TransformToDevice.M11, src.TransformToDevice.M22);
+        }
     }
 }

src/Windows/Avalonia.Win32.Interop/Wpf/WritableBitmapSurface.cs

@@ -24,7 +24,7 @@ namespace Avalonia.Win32.Interop.Wpf
 
         public ILockedFramebuffer Lock()
         {
-            var scale = GetScaling();
+            var scale = _impl.GetScaling();
             var size = new Size(_impl.ActualWidth * scale.X, _impl.ActualHeight * scale.Y);
             var dpi = scale * 96;
             if (_bitmap == null || _bitmap.PixelWidth != (int) size.Width || _bitmap.PixelHeight != (int) size.Height)
@@ -69,13 +69,5 @@ namespace Avalonia.Win32.Interop.Wpf
             public Vector Dpi { get; }
             public PixelFormat Format => PixelFormat.Bgra8888;
         }
-
-        Vector GetScaling()
-        {
-            var src = PresentationSource.FromVisual(_impl)?.CompositionTarget;
-            if (src == null)
-                return new Vector(1, 1);
-            return new Vector(src.TransformToDevice.M11, src.TransformToDevice.M22);
-        }
     }
 }