Fixed some Visuals unit tests.

Ported some stuff from `scenegraph` that was missed in #956, which fixes
some of the failing Avalonia.Visuals.UnitTests.

src/Avalonia.Visuals/Avalonia.Visuals.csproj

@@ -2,6 +2,7 @@
   <PropertyGroup>
     <TargetFramework>netstandard1.1</TargetFramework>
     <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
+    <RootNamespace>Avalonia</RootNamespace>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)' == 'Debug' ">
     <DebugSymbols>true</DebugSymbols>

src/Avalonia.Visuals/Media/LinearGradientBrush.cs

@@ -1,6 +1,8 @@
 // Copyright (c) The Avalonia Project. All rights reserved.
 // Licensed under the MIT license. See licence.md file in the project root for full license information.
 
+using System;
+
 namespace Avalonia.Media
 {
     /// <summary>

src/Avalonia.Visuals/Media/RadialGradientBrush.cs

@@ -4,8 +4,7 @@
 namespace Avalonia.Media
 {
     /// <summary>
-    /// Paints an area with a radial gradient. A focal point defines the beginning of the gradient, 
-    /// and a circle defines the end point of the gradient.
+    /// Paints an area with a radial gradient.
     /// </summary>
     public sealed class RadialGradientBrush : GradientBrush, IRadialGradientBrush, IMutableBrush
     {
@@ -56,6 +55,7 @@ namespace Avalonia.Media
         /// Gets or sets the horizontal and vertical radius of the outermost circle of the radial
         /// gradient.
         /// </summary>
+        // TODO: This appears to always be relative so should use a RelativeSize struct or something.
         public double Radius
         {
             get { return GetValue(RadiusProperty); }

src/Avalonia.Visuals/Visual.cs

@@ -10,7 +10,6 @@ using Avalonia.Collections;
 using Avalonia.Data;
 using Avalonia.Logging;
 using Avalonia.Media;
-using Avalonia.Platform;
 using Avalonia.Rendering;
 using Avalonia.VisualTree;
 
@@ -20,10 +19,10 @@ namespace Avalonia
     /// Base class for controls that provides rendering and related visual properties.
     /// </summary>
     /// <remarks>
-    /// The <see cref="Visual"/> class acts as a node in the Avalonia scene graph and holds
-    /// all the information needed for an <see cref="IRenderTarget"/> to render the control.
-    /// To traverse the scene graph (aka Visual Tree), use the extension methods defined
-    /// in <see cref="VisualExtensions"/>.
+    /// The <see cref="Visual"/> class represents elements that have a visual on-screen
+    /// representation and stores all the information needed for an 
+    /// <see cref="IRenderer"/> to render the control. To traverse the visual tree, use the
+    /// extension methods defined in <see cref="VisualExtensions"/>.
     /// </remarks>
     public class Visual : Animatable, IVisual
     {
@@ -88,6 +87,7 @@ namespace Avalonia
             AvaloniaProperty.Register<Visual, int>(nameof(ZIndex));
 
         private Rect _bounds;
+        private IRenderRoot _visualRoot;
         private IVisual _visualParent;
 
         /// <summary>
@@ -95,7 +95,12 @@ namespace Avalonia
         /// </summary>
         static Visual()
         {
-            AffectsRender(BoundsProperty, IsVisibleProperty, OpacityProperty);
+            AffectsRender(
+                BoundsProperty,
+                ClipProperty,
+                ClipToBoundsProperty,
+                IsVisibleProperty,
+                OpacityProperty);
             RenderTransformProperty.Changed.Subscribe(RenderTransformChanged);
         }
 
@@ -122,7 +127,7 @@ namespace Avalonia
         public event EventHandler<VisualTreeAttachmentEventArgs> DetachedFromVisualTree;
 
         /// <summary>
-        /// Gets the bounds of the scene graph node relative to its parent.
+        /// Gets the bounds of the control relative to its parent.
         /// </summary>
         public Rect Bounds
         {
@@ -131,7 +136,7 @@ namespace Avalonia
         }
 
         /// <summary>
-        /// Gets a value indicating whether the scene graph node should be clipped to its bounds.
+        /// Gets a value indicating whether the control should be clipped to its bounds.
         /// </summary>
         public bool ClipToBounds
         {
@@ -149,7 +154,7 @@ namespace Avalonia
         }
 
         /// <summary>
-        /// Gets a value indicating whether this scene graph node and all its parents are visible.
+        /// Gets a value indicating whether this control and all its parents are visible.
         /// </summary>
         public bool IsEffectivelyVisible
         {
@@ -157,7 +162,7 @@ namespace Avalonia
         }
 
         /// <summary>
-        /// Gets a value indicating whether this scene graph node is visible.
+        /// Gets a value indicating whether this control is visible.
         /// </summary>
         public bool IsVisible
         {
@@ -166,7 +171,7 @@ namespace Avalonia
         }
 
         /// <summary>
-        /// Gets the opacity of the scene graph node.
+        /// Gets the opacity of the control.
         /// </summary>
         public double Opacity
         {
@@ -174,9 +179,8 @@ namespace Avalonia
             set { SetValue(OpacityProperty, value); }
         }
 
-
         /// <summary>
-        /// Gets the opacity mask of the scene graph node.
+        /// Gets the opacity mask of the control.
         /// </summary>
         public IBrush OpacityMask
         {
@@ -185,7 +189,7 @@ namespace Avalonia
         }
 
         /// <summary>
-        /// Gets the render transform of the scene graph node.
+        /// Gets the render transform of the control.
         /// </summary>
         public Transform RenderTransform
         {
@@ -194,7 +198,7 @@ namespace Avalonia
         }
 
         /// <summary>
-        /// Gets the transform origin of the scene graph node.
+        /// Gets the transform origin of the control.
         /// </summary>
         public RelativePoint RenderTransformOrigin
         {
@@ -203,7 +207,7 @@ namespace Avalonia
         }
 
         /// <summary>
-        /// Gets the Z index of the node.
+        /// Gets the Z index of the control.
         /// </summary>
         /// <remarks>
         /// Controls with a higher <see cref="ZIndex"/> will appear in front of controls with
@@ -217,7 +221,7 @@ namespace Avalonia
         }
 
         /// <summary>
-        /// Gets the control's visual children.
+        /// Gets the control's child visuals.
         /// </summary>
         protected IAvaloniaList<IVisual> VisualChildren
         {
@@ -228,24 +232,20 @@ namespace Avalonia
         /// <summary>
         /// Gets the root of the visual tree, if the control is attached to a visual tree.
         /// </summary>
-        protected IRenderRoot VisualRoot
-        {
-            get;
-            private set;
-        }
+        protected IRenderRoot VisualRoot => _visualRoot ?? (this as IRenderRoot);
 
         /// <summary>
-        /// Gets a value indicating whether this scene graph node is attached to a visual root.
+        /// Gets a value indicating whether this control is attached to a visual root.
         /// </summary>
         bool IVisual.IsAttachedToVisualTree => VisualRoot != null;
 
         /// <summary>
-        /// Gets the scene graph node's child nodes.
+        /// Gets the control's child controls.
         /// </summary>
         IAvaloniaReadOnlyList<IVisual> IVisual.VisualChildren => VisualChildren;
 
         /// <summary>
-        /// Gets the scene graph node's parent node.
+        /// Gets the control's parent visual.
         /// </summary>
         IVisual IVisual.VisualParent => _visualParent;
 
@@ -321,7 +321,7 @@ namespace Avalonia
         {
             Logger.Verbose(LogArea.Visual, this, "Attached to visual tree");
 
-            VisualRoot = e.Root;
+            _visualRoot = e.Root;
 
             if (RenderTransform != null)
             {
@@ -329,6 +329,7 @@ namespace Avalonia
             }
 
             OnAttachedToVisualTree(e);
+            InvalidateVisual();
 
             if (VisualChildren != null)
             {
@@ -348,7 +349,7 @@ namespace Avalonia
         {
             Logger.Verbose(LogArea.Visual, this, "Detached from visual tree");
 
-            VisualRoot = null;
+            _visualRoot = null;
 
             if (RenderTransform != null)
             {
@@ -356,6 +357,7 @@ namespace Avalonia
             }
 
             OnDetachedFromVisualTree(e);
+            e.Root?.Renderer?.AddDirty(this);
 
             if (VisualChildren != null)
             {
@@ -492,11 +494,11 @@ namespace Avalonia
             {
                 return;
             }
-            
+
             var old = _visualParent;
             _visualParent = value;
 
-            if (VisualRoot != null)
+            if (_visualRoot != null)
             {
                 var e = new VisualTreeAttachmentEventArgs(old, VisualRoot);
                 OnDetachedFromVisualTreeCore(e);

src/Avalonia.Visuals/VisualTree/IVisual.cs

@@ -9,13 +9,13 @@ using Avalonia.Rendering;
 namespace Avalonia.VisualTree
 {
     /// <summary>
-    /// Represents a node in the visual scene graph.
+    /// Represents control that has a visual on-screen representation.
     /// </summary>
     /// <remarks>
     /// The <see cref="IVisual"/> interface defines the interface required for a renderer to
-    /// render a scene graph. You should not usually need to reference this interface unless
+    /// render a control. You should not usually need to reference this interface unless
     /// you are writing a renderer; instead use the extension methods defined in
-    /// <see cref="VisualExtensions"/> to traverse the scene graph. This interface is
+    /// <see cref="VisualExtensions"/> to traverse the visual tree. This interface is
     /// implemented by <see cref="Visual"/>. It should not be necessary to implement it
     /// anywhere else.
     /// </remarks>
@@ -32,12 +32,12 @@ namespace Avalonia.VisualTree
         event EventHandler<VisualTreeAttachmentEventArgs> DetachedFromVisualTree;
 
         /// <summary>
-        /// Gets the bounds of the scene graph node relative to its parent.
+        /// Gets the bounds of the control relative to its parent.
         /// </summary>
         Rect Bounds { get; }
 
         /// <summary>
-        /// Gets a value indicating whether the scene graph node should be clipped to its bounds.
+        /// Gets a value indicating whether the control should be clipped to its bounds.
         /// </summary>
         bool ClipToBounds { get; set; }
 
@@ -47,47 +47,47 @@ namespace Avalonia.VisualTree
         Geometry Clip { get; set; }
 
         /// <summary>
-        /// Gets a value indicating whether this scene graph node is attached to a visual root.
+        /// Gets a value indicating whether this control is attached to a visual root.
         /// </summary>
         bool IsAttachedToVisualTree { get; }
 
         /// <summary>
-        /// Gets a value indicating whether this scene graph node and all its parents are visible.
+        /// Gets a value indicating whether this control and all its parents are visible.
         /// </summary>
         bool IsEffectivelyVisible { get; }
 
         /// <summary>
-        /// Gets or sets a value indicating whether this scene graph node is visible.
+        /// Gets or sets a value indicating whether this control is visible.
         /// </summary>
         bool IsVisible { get; set; }
 
         /// <summary>
-        /// Gets or sets the opacity of the scene graph node.
+        /// Gets or sets the opacity of the control.
         /// </summary>
         double Opacity { get; set; }
 
         /// <summary>
-        /// Gets or sets the opacity mask of the scene graph node.
+        /// Gets or sets the opacity mask for the control.
         /// </summary>
         IBrush OpacityMask { get; set; }
 
         /// <summary>
-        /// Gets or sets the render transform of the scene graph node.
+        /// Gets or sets the render transform of the control.
         /// </summary>
         Transform RenderTransform { get; set; }
 
         /// <summary>
-        /// Gets or sets the render transform origin of the scene graph node.
+        /// Gets or sets the render transform origin of the control.
         /// </summary>
         RelativePoint RenderTransformOrigin { get; set; }
 
         /// <summary>
-        /// Gets the scene graph node's child nodes.
+        /// Gets the control's child visuals.
         /// </summary>
         IAvaloniaReadOnlyList<IVisual> VisualChildren { get; }
 
         /// <summary>
-        /// Gets the scene graph node's parent node.
+        /// Gets the control's parent visual.
         /// </summary>
         IVisual VisualParent { get; }
 
@@ -107,7 +107,7 @@ namespace Avalonia.VisualTree
         void InvalidateVisual();
 
         /// <summary>
-        /// Renders the scene graph node to a <see cref="DrawingContext"/>.
+        /// Renders the control to a <see cref="DrawingContext"/>.
         /// </summary>
         /// <param name="context">The context.</param>
         void Render(DrawingContext context);

src/Avalonia.Visuals/VisualTree/VisualExtensions.cs

@@ -4,6 +4,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using Avalonia.Rendering;
 
 namespace Avalonia.VisualTree
 {
@@ -20,6 +21,8 @@ namespace Avalonia.VisualTree
         /// <returns>The common ancestor, or null if not found.</returns>
         public static IVisual FindCommonVisualAncestor(this IVisual visual, IVisual target)
         {
+            Contract.Requires<ArgumentNullException>(visual != null);
+
             return visual.GetSelfAndVisualAncestors().Intersect(target.GetSelfAndVisualAncestors())
                 .FirstOrDefault();
         }
@@ -49,6 +52,8 @@ namespace Avalonia.VisualTree
         /// <returns>The visual and its ancestors.</returns>
         public static IEnumerable<IVisual> GetSelfAndVisualAncestors(this IVisual visual)
         {
+            Contract.Requires<ArgumentNullException>(visual != null);
+
             yield return visual;
 
             foreach (var ancestor in visual.GetVisualAncestors())
@@ -102,26 +107,9 @@ namespace Avalonia.VisualTree
         {
             Contract.Requires<ArgumentNullException>(visual != null);
 
-            if (filter?.Invoke(visual) != false)
-            {
-                bool containsPoint = BoundsTracker.GetTransformedBounds((Visual)visual)?.Contains(p) == true;
-
-                if ((containsPoint || !visual.ClipToBounds) && visual.VisualChildren.Any())
-                {
-                    foreach (var child in visual.VisualChildren.SortByZIndex())
-                    {
-                        foreach (var result in child.GetVisualsAt(p, filter))
-                        {
-                            yield return result;
-                        }
-                    }
-                }
-
-                if (containsPoint)
-                {
-                    yield return visual;
-                }
-            }
+            var root = visual.GetVisualRoot();
+            p = visual.TranslatePoint(p, root);
+            return root.Renderer.HitTest(p, filter);
         }
 
         /// <summary>
@@ -197,11 +185,11 @@ namespace Avalonia.VisualTree
         /// <returns>
         /// The root visual or null if the visual is not rooted.
         /// </returns>
-        public static IVisual GetVisualRoot(this IVisual visual)
+        public static IRenderRoot GetVisualRoot(this IVisual visual)
         {
             Contract.Requires<ArgumentNullException>(visual != null);
 
-            return visual.VisualRoot as IVisual;
+            return visual.VisualRoot as IRenderRoot ?? visual.VisualRoot;
         }
 
         /// <summary>

tests/Avalonia.Controls.UnitTests/WindowBaseTests.cs

@@ -198,7 +198,7 @@ namespace Avalonia.Controls.UnitTests
             public bool IsClosed { get; private set; }
 
             public TestWindowBase()
-                : base(Mock.Of<IWindowBaseImpl>())
+                : base(Mock.Of<IWindowBaseImpl>(x => x.Scaling == 1))
             {
             }
 

tests/Avalonia.LeakTests/ControlTests.cs

@@ -4,18 +4,15 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
-using JetBrains.dotMemoryUnit;
-using Avalonia.Collections;
 using Avalonia.Controls;
-using Avalonia.Controls.Primitives;
 using Avalonia.Controls.Templates;
 using Avalonia.Diagnostics;
 using Avalonia.Layout;
 using Avalonia.Platform;
 using Avalonia.Rendering;
-using Avalonia.Styling;
 using Avalonia.UnitTests;
 using Avalonia.VisualTree;
+using JetBrains.dotMemoryUnit;
 using Moq;
 using Xunit;
 using Xunit.Abstractions;
@@ -57,7 +54,6 @@ namespace Avalonia.LeakTests
                 };
 
                 var result = run();
-                PurgeMoqReferences();
 
                 dotMemory.Check(memory =>
                     Assert.Equal(0, memory.GetObjects(where => where.Type.Is<Canvas>()).ObjectsCount));
@@ -95,7 +91,6 @@ namespace Avalonia.LeakTests
                 };
 
                 var result = run();
-                PurgeMoqReferences();
 
                 dotMemory.Check(memory =>
                     Assert.Equal(0, memory.GetObjects(where => where.Type.Is<Canvas>()).ObjectsCount));
@@ -134,7 +129,6 @@ namespace Avalonia.LeakTests
                 };
 
                 var result = run();
-                PurgeMoqReferences();
 
                 dotMemory.Check(memory =>
                     Assert.Equal(0, memory.GetObjects(where => where.Type.Is<TextBox>()).ObjectsCount));
@@ -172,7 +166,6 @@ namespace Avalonia.LeakTests
                 };
 
                 var result = run();
-                PurgeMoqReferences();
 
                 dotMemory.Check(memory =>
                     Assert.Equal(0, memory.GetObjects(where => where.Type.Is<TextBox>()).ObjectsCount));
@@ -218,7 +211,6 @@ namespace Avalonia.LeakTests
                 };
 
                 var result = run();
-                PurgeMoqReferences();
 
                 dotMemory.Check(memory =>
                     Assert.Equal(0, memory.GetObjects(where => where.Type.Is<TextBox>()).ObjectsCount));
@@ -309,7 +301,6 @@ namespace Avalonia.LeakTests
                 };
 
                 var result = run();
-                PurgeMoqReferences();
 
                 dotMemory.Check(memory =>
                     Assert.Equal(0, memory.GetObjects(where => where.Type.Is<TreeView>()).ObjectsCount));
@@ -343,14 +334,6 @@ namespace Avalonia.LeakTests
             }
         }
 
-        private static void PurgeMoqReferences()
-        {
-            // Moq holds onto references in its mock of IRenderer in case we want to check if a method has been called;
-            // clear these.
-            var renderer = Mock.Get(AvaloniaLocator.Current.GetService<IRenderer>());
-            renderer.ResetCalls();
-        }
-
         private class Node
         {
             public string Name { get; set; }

tests/Avalonia.UnitTests/TestRoot.cs

@@ -8,12 +8,22 @@ using Avalonia.Layout;
 using Avalonia.Platform;
 using Avalonia.Rendering;
 using Avalonia.Styling;
+using Moq;
 
 namespace Avalonia.UnitTests
 {
     public class TestRoot : Decorator, IFocusScope, ILayoutRoot, INameScope, IRenderRoot, IStyleRoot
     {
         private readonly NameScope _nameScope = new NameScope();
+        private readonly IRenderTarget _renderTarget = Mock.Of<IRenderTarget>(
+            x => x.CreateDrawingContext(It.IsAny<IVisualBrushRenderer>()) == Mock.Of<IDrawingContextImpl>());
+
+        public TestRoot()
+        {
+            var rendererFactory = AvaloniaLocator.Current.GetService<IRendererFactory>();
+            var renderLoop = AvaloniaLocator.Current.GetService<IRenderLoop>();
+            Renderer = rendererFactory?.CreateRenderer(this, renderLoop);
+        }
 
         event EventHandler<NameScopeEventArgs> INameScope.Registered
         {
@@ -41,16 +51,12 @@ namespace Avalonia.UnitTests
 
         public IRenderTarget RenderTarget => null;
 
-        public IRenderer Renderer => null;
+        public IRenderer Renderer { get; set; }
 
-        public IRenderTarget CreateRenderTarget()
-        {
-            throw new NotImplementedException();
-        }
+        public IRenderTarget CreateRenderTarget() => _renderTarget;
 
         public void Invalidate(Rect rect)
         {
-            throw new NotImplementedException();
         }
 
         public Point PointToClient(Point p) => p;