Added FPS counter to test app.

Cairo/Perspex.Cairo/Renderer.cs

@@ -28,6 +28,15 @@ namespace Perspex.Cairo
         {
         }
 
+        /// <summary>
+        /// Gets the number of times <see cref="Render"/> has been called.
+        /// </summary>
+        public int RenderCount
+        {
+            get;
+            private set;
+        }
+
         /// <summary>
         /// Renders the specified visual.
         /// </summary>
@@ -39,6 +48,8 @@ namespace Perspex.Cairo
             {
                 this.Render(visual, context);
             }
+
+            ++this.RenderCount;
         }
 
         /// <summary>

Perspex.Controls.UnitTests/ControlTests.cs

@@ -12,6 +12,7 @@ namespace Perspex.Controls.UnitTests
     using Moq;
     using Perspex.Controls;
     using Perspex.Layout;
+    using Perspex.Platform;
     using Perspex.Rendering;
     using Perspex.Styling;
     using Splat;
@@ -82,6 +83,11 @@ namespace Perspex.Controls.UnitTests
                 get { throw new System.NotImplementedException(); }
             }
 
+            public IRenderer Renderer
+            {
+                get { throw new NotImplementedException(); }
+            }
+
             public IRenderManager RenderManager
             {
                 get { throw new NotImplementedException(); }

Perspex.Controls.UnitTests/TestRoot.cs

@@ -9,6 +9,7 @@ namespace Perspex.Controls.UnitTests
     using System;
     using Moq;
     using Perspex.Layout;
+    using Perspex.Platform;
     using Perspex.Rendering;
 
     internal class TestRoot : Decorator, ILayoutRoot, IRenderRoot
@@ -23,6 +24,11 @@ namespace Perspex.Controls.UnitTests
             get { return new Mock<ILayoutManager>().Object; }
         }
 
+        public IRenderer Renderer
+        {
+            get { throw new NotImplementedException(); }
+        }
+
         public IRenderManager RenderManager
         {
             get { throw new NotImplementedException(); }

Perspex.Controls/Window.cs

@@ -30,6 +30,8 @@ namespace Perspex.Controls
 
         private Dispatcher dispatcher;
 
+        private IRenderManager renderManager;
+
         private IRenderer renderer;
 
         private IInputManager inputManager;
@@ -47,7 +49,7 @@ namespace Perspex.Controls
             this.impl = Locator.Current.GetService<IWindowImpl>();
             this.inputManager = Locator.Current.GetService<IInputManager>();
             this.LayoutManager = Locator.Current.GetService<ILayoutManager>();
-            this.RenderManager = Locator.Current.GetService<IRenderManager>();
+            this.renderManager = Locator.Current.GetService<IRenderManager>();
 
             if (renderInterface == null)
             {
@@ -73,7 +75,7 @@ namespace Perspex.Controls
                     "Could not create layout manager: maybe Application.RegisterServices() wasn't called?");
             }
 
-            if (this.RenderManager == null)
+            if (this.renderManager == null)
             {
                 throw new InvalidOperationException(
                     "Could not create render manager: maybe Application.RegisterServices() wasn't called?");
@@ -92,7 +94,7 @@ namespace Perspex.Controls
 
             this.LayoutManager.Root = this;
             this.LayoutManager.LayoutNeeded.Subscribe(_ => this.HandleLayoutNeeded());
-            this.RenderManager.RenderNeeded.Subscribe(_ => this.HandleRenderNeeded());
+            this.renderManager.RenderNeeded.Subscribe(_ => this.HandleRenderNeeded());
 
             this.GetObservable(TitleProperty).Subscribe(s => this.impl.SetTitle(s));
 
@@ -122,10 +124,14 @@ namespace Perspex.Controls
             private set;
         }
 
-        public IRenderManager RenderManager
+        IRenderer IRenderRoot.Renderer
         {
-            get;
-            private set;
+            get { return this.renderer; }
+        }
+
+        IRenderManager IRenderRoot.RenderManager
+        {
+            get { return this.renderManager; }
         }
 
         public void Show()
@@ -172,7 +178,7 @@ namespace Perspex.Controls
         private void HandlePaint(Rect rect, IPlatformHandle handle)
         {
             this.renderer.Render(this, handle);
-            this.RenderManager.RenderFinished();
+            this.renderManager.RenderFinished();
         }
 
         private void HandleResized(Size size)

Perspex.SceneGraph.UnitTests/TestRoot.cs

@@ -6,12 +6,16 @@
 namespace Perspex.SceneGraph.UnitTests
 {
     using System;
-    using System.Collections.Generic;
-    using System.Linq;
+    using Perspex.Platform;
     using Perspex.Rendering;
 
     public class TestRoot : TestVisual, IRenderRoot
     {
+        public IRenderer Renderer
+        {
+            get { throw new NotImplementedException(); }
+        }
+
         public IRenderManager RenderManager
         {
             get { throw new NotImplementedException(); }

Perspex.SceneGraph/Platform/IRenderer.cs

@@ -10,6 +10,11 @@ namespace Perspex.Platform
 
     public interface IRenderer
     {
+        /// <summary>
+        /// Gets the number of times <see cref="Render"/> has been called.
+        /// </summary>
+        int RenderCount { get; }
+
         /// <summary>
         /// Renders the specified visual.
         /// </summary>

Perspex.SceneGraph/Rendering/IRenderRoot.cs

@@ -6,8 +6,12 @@
 
 namespace Perspex.Rendering
 {
+    using Perspex.Platform;
+
     public interface IRenderRoot
     {
+        IRenderer Renderer { get; }
+
         IRenderManager RenderManager { get; }
     }
 }

TestApplication/Program.cs

@@ -9,6 +9,7 @@ using Perspex.Diagnostics;
 using Perspex.Layout;
 using Perspex.Media;
 using Perspex.Media.Imaging;
+using Perspex.Rendering;
 using Perspex.Styling;
 using Perspex.Threading;
 #if PERSPEX_GTK
@@ -115,11 +116,18 @@ namespace TestApplication
                 },
             };
 
+            TextBlock fps;
+
             Window window = new Window
             {
                 Title = "Perspex Test Application",
                 Content = new Grid
                 {
+                    ColumnDefinitions = new ColumnDefinitions
+                    {
+                        new ColumnDefinition(1, GridUnitType.Star),
+                        new ColumnDefinition(1, GridUnitType.Star),
+                    },
                     RowDefinitions = new RowDefinitions
                     {
                         new RowDefinition(1, GridUnitType.Star),
@@ -138,21 +146,38 @@ namespace TestApplication
                                 SlidersTab(),
                                 LayoutTab(),
                                 AnimationsTab(),
-                            }
+                            },
+                            [Grid.ColumnSpanProperty] = 2,
                         },
+                        (fps = new TextBlock
+                        {
+                            HorizontalAlignment = HorizontalAlignment.Left,
+                            Margin = new Thickness(2),
+                            [Grid.RowProperty] = 1,
+                        }),
                         new TextBlock
                         {
                             Text = "Press F12 for Dev Tools",
                             HorizontalAlignment = HorizontalAlignment.Right,
                             Margin = new Thickness(2),
+                            [Grid.ColumnProperty] = 1,
                             [Grid.RowProperty] = 1,
-                        }
+                        },
                     }
                 },
             };
 
             DevTools.Attach(window);
 
+            var renderer = ((IRenderRoot)window).Renderer;
+            var last = renderer.RenderCount;
+            DispatcherTimer.Run(() =>
+            {
+                fps.Text = "FPS: " + (renderer.RenderCount - last);
+                last = renderer.RenderCount;
+                return true;
+            }, TimeSpan.FromSeconds(1));
+
             window.Show();
             Application.Current.Run(window);
         }
@@ -508,11 +533,11 @@ namespace TestApplication
             };
 
             Animate.Property(
-                (PerspexObject)rect1.RenderTransform, 
-                RotateTransform.AngleProperty, 
-                0.0, 
-                360.0, 
-                new LinearDoubleEasing(), 
+                (PerspexObject)rect1.RenderTransform,
+                RotateTransform.AngleProperty,
+                0.0,
+                360.0,
+                new LinearDoubleEasing(),
                 TimeSpan.FromSeconds(4),
                 double.PositiveInfinity);
 

Windows/Perspex.Direct2D1/Renderer.cs

@@ -81,6 +81,15 @@ namespace Perspex.Direct2D1
             private set;
         }
 
+        /// <summary>
+        /// Gets the number of times <see cref="Render"/> has been called.
+        /// </summary>
+        public int RenderCount
+        {
+            get;
+            private set;
+        }
+
         /// <summary>
         /// Renders the specified visual.
         /// </summary>
@@ -92,6 +101,8 @@ namespace Perspex.Direct2D1
             {
                 this.Render(visual, context);
             }
+
+            ++this.RenderCount;
         }
 
         /// <summary>