Merge branch 'master' into style-resources

docs/.gitignore

@@ -0,0 +1,3 @@
+#docfx
+_site
+api

docs/README.md

@@ -0,0 +1,21 @@
+# Perspex Documentation
+
+* [API Reference](http://perspex.github.io/)
+
+## Building
+
+Download and unzip `docfx.zip` into `Documentation` folder from [DocFX project site](https://github.com/dotnet/docfx/releases).
+
+**Step 1.** To create `_site` documentation folder run build script
+
+```
+build.cmd
+```
+
+**Step 2.** To browse `_site` documentation folder run serve script
+
+```
+serve.cmd
+```
+
+And you can view the generated website in your browser `http://localhost:8080`.

docs/build.cmd

@@ -0,0 +1,3 @@
+@echo off
+docfx metadata
+docfx build

docs/docfx.json

@@ -0,0 +1,55 @@
+{
+  "metadata": [
+    {
+      "src": [
+        {
+          "files": [
+            "/src/Gtk/Perspex.Cairo/Perspex.Cairo.csproj",
+            "/src/Gtk/Perspex.Gtk/Perspex.Gtk.csproj",
+            "/src/Markup/Perspex.Markup/Perspex.Markup.csproj",
+            "/src/Markup/Perspex.Markup.Xaml/Perspex.Markup.Xaml.csproj",
+            "/src/Perspex.Animation/Perspex.Animation.csproj",
+            "/src/Perspex.Application/Perspex.Application.csproj",
+            "/src/Perspex.Base/Perspex.Base.csproj",
+            "/src/Perspex.Controls/Perspex.Controls.csproj",
+            "/src/Perspex.Diagnostics/Perspex.Diagnostics.csproj",
+            "/src/Perspex.HtmlRenderer/Perspex.HtmlRenderer.csproj",
+            "/src/Perspex.Input/Perspex.Input.csproj",
+            "/src/Perspex.Interactivity/Perspex.Interactivity.csproj",
+            "/src/Perspex.Layout/Perspex.Layout.csproj",
+            "/src/Perspex.ReactiveUI/Perspex.ReactiveUI.csproj",
+            "/src/Perspex.SceneGraph/Perspex.SceneGraph.csproj",
+            "/src/Perspex.Styling/Perspex.Styling.csproj",
+            "/src/Perspex.Themes.Default/Perspex.Themes.Default.csproj",
+            "/src/Skia/Perspex.Skia.Desktop/Perspex.Skia.Desktop.csproj",
+            "/src/Windows/Perspex.Designer/Perspex.Designer.csproj",
+            "/src/Windows/Perspex.Direct2D1/Perspex.Direct2D1.csproj",
+            "/src/Windows/Perspex.Win32/Perspex.Win32.csproj",
+          ],
+          "exclude": [ "**/bin/**", "**/obj/**" ], 
+          "cwd": ".."
+        }
+      ],
+      "dest": "api"
+    },
+  ],
+  "build": {
+    "content":
+      [
+        {
+          "files": ["**/*.yml", "index.md", "tutorial/*.md", "guidelines/*.md", "spec/*.md"],
+        }
+      ],
+    "resource": [
+        {
+          "files": ["images/**", "tutorial/images/**", "guidelines/images/**", "spec/images/**"]
+        }
+    ],
+    "overwrite": "apidoc/*.md",
+    "globalMetadata": {
+      "_appTitle": "Perspex Website"
+    },
+    "dest": "_site",
+    "template": "default"
+  }
+}

docs/guidelines/toc.yml

@@ -0,0 +1,4 @@
+- name: Building Perspex 
+  href: build.md
+- name: Contributing
+  href: contributing.md

docs/index.md

@@ -0,0 +1,37 @@
+# The Perspex UI Framework
+
+Cross platform .NET UI Framework with bindings and XAML
+
+## Current status
+
+We're pleased to announce that Perspex is now in alpha!
+
+What does alpha mean? Well, it means that it's now at a stage where you can have a play and hopefully create simple applications. There's now a Visual Studio Extension containing project and item templates that will help you get started, and there's an initial complement of controls. There's still a lot missing, and you will find bugs, and the API will change, but this represents the first time where we've made it somewhat easy to have a play and experiment with the framework.
+
+## How do I try it out
+
+The easiest way to try out Perspex is to install the [Visual Studio Extension](https://visualstudiogallery.msdn.microsoft.com/a4542e8a-b56c-4295-8df1-7e220178b873).
+
+This will add a Perspex project template and a Window template to the standard Visual Studo "Add" dialog (yes, icons still to come :) ):
+
+![](images/add-dialogs.png)
+
+Creating a Perspex Project will give you a simple project with a single XAML window. We even have a simple designer:
+
+![](images/hello-world-xaml.png)
+
+You can also find the project [on GitHub](https://github.com/Perspex/Perspex/)
+
+## News
+
+You can read news about Perspex on [Groky's blog](http://grokys.github.io/)
+
+## Cross Platform
+
+Fow now we can run on Windows, Linux and Mac.
+
+![](images/cross-platform.png)
+
+## Inspection support
+
+![](images/inspection-support.png)

docs/serve.cmd

@@ -0,0 +1,2 @@
+@echo off
+docfx serve _site

docs/spec/toc.yml

@@ -0,0 +1,8 @@
+- name: Perspex Architecture
+  href: architecture.md
+- name: Styling in Perspex
+  href: styles.md
+- name: Defining Properties
+  href: defining-properties.md
+- name: Working with Properties
+  href: working-with-properties.md

docs/toc.yml

@@ -0,0 +1,10 @@
+- name: Home
+  href: index.md
+- name: Getting Started
+  href: tutorial/
+- name: Guidelines
+  href: guidelines/
+- name: Specifications
+  href: spec/
+- name: API Documentation
+  href: api/

docs/gettingstarted.md → docs/tutorial/gettingstarted.md

@@ -1,8 +1,8 @@
-# Getting Started
+# Getting Started
 
 ## Windows
 
-![](add-dialogs.png)
+![](images/add-dialogs.png)
 
 The easiest way to try out Perspex is to install the Visual Studio Extension.
 
@@ -12,4 +12,4 @@ This will add a Perspex project template and a Window template to the standard V
 
 It is a little more manual on non-Windows platforms, but using Xamarin Studio you can install the Perspex NuGet package.
 
-![](add-packages.png)
+![](images/add-packages.png)

docs/tutorial/toc.yml

@@ -0,0 +1,2 @@
+- name: Getting Started
+  href: gettingstarted.md

readme.md

@@ -5,11 +5,11 @@
 
 A multi-platform .NET UI framework. It can run on Windows, Linux, Mac OS X, iOS and Android.
 
-![](docs/screen.png)
+![](docs/images/screen.png)
 
 Desktop platforms:
 
-<a href='https://www.youtube.com/watch?t=28&v=c_AB_XSILp0' target='_blank'>![](docs/perspex-video.png)<a/>
+<a href='https://www.youtube.com/watch?t=28&v=c_AB_XSILp0' target='_blank'>![](docs/images/perspex-video.png)<a/>
 
 Mobile platforms:
 
@@ -43,19 +43,19 @@ framework.
 ## Documentation
 
 As mentioned above, Perspex is still in alpha and as such there's not much documentation yet. You can
-take a look at the [getting started page](docs/gettingstarted.md) for an
+take a look at the [getting started page](docs/tutorial/gettingstarted.md) for an
 overview of how to get started but probably the best thing to do for now is to already know a little bit
 about WPF/Silverlight/UWP/XAML and ask questions in our [Gitter room](https://gitter.im/Perspex/Perspex).
 
-There's also a high-level [architecture document](docs/architecture.md) that is currently a little bit
+There's also a high-level [architecture document](docs/spec/architecture.md) that is currently a little bit
 out of date, and I've also started writing blog posts on Perspex at http://grokys.github.io/.
 
 Contributions are always welcome!
 
 ## Building and Using
 
-See the [build instructions here](https://github.com/grokys/Perspex/blob/master/docs/build.md)
+See the [build instructions here](docs/guidelines/build.md)
 
 ## Contributing ##
 
-Please read the [contribution guidelines](docs/contributing.md) before submitting a pull request.
+Please read the [contribution guidelines](docs/guidelines/contributing.md) before submitting a pull request.

src/Android/Perspex.Android/Platform/SkiaPlatform/WindowImpl.cs

@@ -85,6 +85,8 @@ namespace Perspex.Android.Platform.SkiaPlatform
 
         public Action<Size> Resized { get; set; }
 
+        public Action<double> ScalingChanged { get; set; }
+
         public View View => this;
 
         Action ITopLevelImpl.Activated { get; set; }
@@ -149,6 +151,8 @@ namespace Perspex.Android.Platform.SkiaPlatform
 
         public Point Position { get; set; }
 
+        public double Scaling => 1;
+
         public IDisposable ShowDialog()
         {
             throw new NotImplementedException();

src/Gtk/Perspex.Gtk/WindowImpl.cs

@@ -108,6 +108,8 @@ namespace Perspex.Gtk
             }
         }
 
+        public double Scaling => 1;
+
         IPlatformHandle ITopLevelImpl.Handle => this;
 
         [DllImport("libgdk-win32-2.0-0.dll", CallingConvention = CallingConvention.Cdecl)]
@@ -160,6 +162,8 @@ namespace Perspex.Gtk
 
         public Action<Size> Resized { get; set; }
 
+        public Action<double> ScalingChanged { get; set; }
+
         public IPopupImpl CreatePopup()
         {
             return new PopupImpl();

src/Markup/Perspex.Markup.Xaml/Context/PerspexMemberValuePlugin.cs

@@ -2,6 +2,7 @@
 // Licensed under the MIT license. See licence.md file in the project root for full license information.
 
 using System;
+using OmniXaml.TypeConversion;
 using OmniXaml.Typing;
 
 namespace Perspex.Markup.Xaml.Context
@@ -16,9 +17,9 @@ namespace Perspex.Markup.Xaml.Context
             _xamlMember = xamlMember;
         }
 
-        public override void SetValue(object instance, object value)
+        public override void SetValue(object instance, object value, IValueContext valueContext)
         {
-            PropertyAccessor.SetValue(instance, _xamlMember, value);
+            PropertyAccessor.SetValue(instance, _xamlMember, value, valueContext);
         }
     }
 }

src/Markup/Perspex.Markup.Xaml/Context/PerspexObjectAssembler.cs

@@ -4,19 +4,21 @@
 using System;
 using OmniXaml;
 using OmniXaml.ObjectAssembler;
-using Perspex.Controls;
+using OmniXaml.ObjectAssembler.Commands;
+using OmniXaml.TypeConversion;
 using Perspex.Markup.Xaml.Templates;
 
 namespace Perspex.Markup.Xaml.Context
 {
-    using OmniXaml.ObjectAssembler.Commands;
-
     public class PerspexObjectAssembler : IObjectAssembler
     {
         private readonly TemplateHostingObjectAssembler objectAssembler;
         private readonly ObjectAssembler assembler;
 
-        public PerspexObjectAssembler(IRuntimeTypeSource runtimeTypeSource, Settings objectAssemblerSettings = null)
+        public PerspexObjectAssembler(
+            IRuntimeTypeSource typeSource, 
+            ITopDownValueContext topDownValueContext, 
+            Settings settings = null)
         {
             var mapping = new DeferredLoaderMapping();
             mapping.Map<ControlTemplate>(x => x.Content, new TemplateLoader());
@@ -25,7 +27,8 @@ namespace Perspex.Markup.Xaml.Context
             mapping.Map<TreeDataTemplate>(x => x.Content, new TemplateLoader());
             mapping.Map<ItemsPanelTemplate>(x => x.Content, new TemplateLoader());
 
-            assembler = new ObjectAssembler(runtimeTypeSource, new TopDownValueContext(), objectAssemblerSettings);
+            var valueContext = new ValueContext(typeSource, topDownValueContext);
+            assembler = new ObjectAssembler(typeSource, valueContext, settings);
             objectAssembler = new TemplateHostingObjectAssembler(assembler, mapping);
         }
 

src/Markup/Perspex.Markup.Xaml/Context/PerspexParserFactory.cs

@@ -26,7 +26,10 @@ namespace Perspex.Markup.Xaml.Context
         {
             var xamlInstructionParser = new OrderAwareInstructionParser(new InstructionParser(runtimeTypeSource));
 
-            IObjectAssembler objectAssembler = new PerspexObjectAssembler(runtimeTypeSource, settings);
+            IObjectAssembler objectAssembler = new PerspexObjectAssembler(
+                runtimeTypeSource,
+                new TopDownValueContext(),
+                settings);
             var phaseParserKit = new PhaseParserKit(
                 new ProtoInstructionParser(runtimeTypeSource),
                 xamlInstructionParser,

src/Markup/Perspex.Markup.Xaml/Context/PropertyAccessor.cs

@@ -6,6 +6,7 @@ using System.Linq;
 using System.Reflection;
 using System.Runtime.CompilerServices;
 using OmniXaml.ObjectAssembler;
+using OmniXaml.TypeConversion;
 using OmniXaml.Typing;
 using Perspex.Data;
 using Perspex.Styling;
@@ -14,7 +15,11 @@ namespace Perspex.Markup.Xaml.Context
 {
     internal static class PropertyAccessor
     {
-        public static void SetValue(object instance, MutableMember member, object value)
+        public static void SetValue(
+            object instance, 
+            MutableMember member, 
+            object value,
+            IValueContext context)
         {
             var perspexProperty = FindPerspexProperty(instance, member);
 
@@ -31,9 +36,13 @@ namespace Perspex.Markup.Xaml.Context
                 // TODO: Make this more generic somehow.
                 var setter = (Setter)instance;
                 var targetType = setter.Property.PropertyType;
-                var valuePipeline = new ValuePipeline(member.TypeRepository, null);
                 var xamlType = member.TypeRepository.GetByType(targetType);
-                SetClrProperty(instance, member, valuePipeline.ConvertValueIfNecessary(value, xamlType));
+                var convertedValue = default(object);
+
+                if (CommonValueConversion.TryConvert(value, xamlType, context, out convertedValue))
+                {
+                    SetClrProperty(instance, member, convertedValue);
+                }
             }
             else
             {

src/Markup/Perspex.Markup.Xaml/Converters/BitmapTypeConverter.cs

@@ -11,17 +11,17 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class BitmapTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             var uri = new Uri((string)value, UriKind.RelativeOrAbsolute);
             var scheme = uri.IsAbsoluteUri ? uri.Scheme : "file";
@@ -36,7 +36,7 @@ namespace Perspex.Markup.Xaml.Converters
             }
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/BrushTypeConverter.cs

@@ -10,22 +10,22 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class BrushTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             return Brush.Parse((string)value);
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/ClassesTypeConverter.cs

@@ -11,22 +11,22 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class ClassesTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             return new Classes(((string)value).Split(' '));
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/ColorTypeConverter.cs

@@ -10,22 +10,22 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class ColorTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             return Color.Parse((string)value);
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/ColumnDefinitionsTypeConverter.cs

@@ -10,22 +10,22 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class ColumnDefinitionsTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             return new ColumnDefinitions((string)value);
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/CursorTypeConverter.cs

@@ -12,23 +12,23 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class CursorTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             var cursor = (StandardCursorType)Enum.Parse(typeof (StandardCursorType), ((string) value).Trim(), true);
             return new Cursor(cursor);
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/GeometryTypeConverter.cs

@@ -7,22 +7,22 @@ namespace Perspex.Markup.Xaml.Converters
 
     public class GeometryTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             return StreamGeometry.Parse((string)value);
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/GridLengthTypeConverter.cs

@@ -10,22 +10,22 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class GridLengthTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             return GridLength.Parse((string)value, culture);
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/KeyGestureConverter.cs

@@ -7,22 +7,22 @@ namespace Perspex.Markup.Xaml.Converters
 {
     class KeyGestureConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             return KeyGesture.Parse((string)value);
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/MemberSelectorTypeConverter.cs

@@ -10,17 +10,17 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class MemberSelectorTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             return new MemberSelector
             {
@@ -28,7 +28,7 @@ namespace Perspex.Markup.Xaml.Converters
             };
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/PerspexListTypeConverter.cs

@@ -12,17 +12,17 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class PerspexListTypeConverter<T> : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             var result = new PerspexList<T>();
             var values = ((string)value).Split(',');
@@ -44,7 +44,7 @@ namespace Perspex.Markup.Xaml.Converters
             return result;
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/PerspexPropertyTypeConverter.cs

@@ -12,17 +12,17 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class PerspexPropertyTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             var s = (string)value;
 
@@ -68,7 +68,7 @@ namespace Perspex.Markup.Xaml.Converters
             return property;
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/PointTypeConverter.cs

@@ -9,22 +9,22 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class PointTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             return Point.Parse((string)value, culture);
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/PointsListTypeConverter.cs

@@ -10,17 +10,17 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class PointsListTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             string strValue = (string)value;
             string[] pointStrs = strValue.Split(new[] { ' ', '\t', '\r', '\n' }, StringSplitOptions.RemoveEmptyEntries);
@@ -32,7 +32,7 @@ namespace Perspex.Markup.Xaml.Converters
             return result;
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/RelativePointTypeConverter.cs

@@ -9,22 +9,22 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class RelativePointTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             return RelativePoint.Parse((string)value, culture);
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/RelativeRectTypeConverter.cs

@@ -9,22 +9,22 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class RelativeRectTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             return RelativeRect.Parse((string)value, culture);
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/RowDefinitionsTypeConverter.cs

@@ -10,22 +10,22 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class RowDefinitionsTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             return new RowDefinitions((string)value);
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/SelectorTypeConverter.cs

@@ -10,23 +10,23 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class SelectorTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             var parser = new SelectorParser((t, ns) => context.TypeRepository.GetByPrefix(ns ?? "", t).UnderlyingType);
             return parser.Parse((string)value);
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/ThicknessTypeConverter.cs

@@ -9,22 +9,22 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class ThicknessTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             return Thickness.Parse((string)value, culture);
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/TimeSpanTypeConverter.cs

@@ -10,17 +10,17 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class TimeSpanTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             var valueStr = (string)value;
             if (!valueStr.Contains(":"))
@@ -33,7 +33,7 @@ namespace Perspex.Markup.Xaml.Converters
             return TimeSpan.Parse(valueStr);
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/Converters/UriTypeConverter.cs

@@ -9,22 +9,22 @@ namespace Perspex.Markup.Xaml.Converters
 {
     public class UriTypeConverter : ITypeConverter
     {
-        public bool CanConvertFrom(ITypeConverterContext context, Type sourceType)
+        public bool CanConvertFrom(IValueContext context, Type sourceType)
         {
             return sourceType == typeof(string);
         }
 
-        public bool CanConvertTo(ITypeConverterContext context, Type destinationType)
+        public bool CanConvertTo(IValueContext context, Type destinationType)
         {
             return false;
         }
 
-        public object ConvertFrom(ITypeConverterContext context, CultureInfo culture, object value)
+        public object ConvertFrom(IValueContext context, CultureInfo culture, object value)
         {
             return new Uri((string)value);
         }
 
-        public object ConvertTo(ITypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        public object ConvertTo(IValueContext context, CultureInfo culture, object value, Type destinationType)
         {
             throw new NotImplementedException();
         }

src/Markup/Perspex.Markup.Xaml/OmniXAML

@@ -1 +1 @@
-Subproject commit 5209a3f26268fc55b82fbf8a05fbedce160e230f
+Subproject commit 307361d65a187d404da1d4e15a553d918c3ed79c

src/Markup/Perspex.Markup.Xaml/Perspex.Markup.Xaml.csproj

@@ -169,9 +169,9 @@
     <Compile Include="OmniXAML\Source\OmniXaml\ObjectAssembler\PreviousLevelWrapper.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\ObjectAssembler\Settings.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\ObjectAssembler\StateCommuter.cs" />
+    <Compile Include="OmniXAML\Source\OmniXaml\ObjectAssembler\StoredInstance.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\ObjectAssembler\TopDownValueContext.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\ObjectAssembler\TypeOperations.cs" />
-    <Compile Include="OmniXAML\Source\OmniXaml\ObjectAssembler\ValuePipeline.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\ObjectAssembler\ValueProcessingMode.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\ObjectAssembler\XamlSetValueEventArgs.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\ParseException.cs" />
@@ -215,17 +215,18 @@
     <Compile Include="OmniXAML\Source\OmniXaml\TypeConversion\BuiltInConverters\StringTypeConverter.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\TypeConversion\BuiltInConverters\TypeTypeConverter.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\TypeConversion\ITypeConverter.cs" />
-    <Compile Include="OmniXAML\Source\OmniXaml\TypeConversion\ITypeConverterContext.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\TypeConversion\ITypeConverterProvider.cs" />
+    <Compile Include="OmniXAML\Source\OmniXaml\TypeConversion\IValueContext.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\TypeConversion\TypeConverterAttribute.cs" />
-    <Compile Include="OmniXAML\Source\OmniXaml\TypeConversion\TypeConverterContext.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\TypeConversion\TypeConverterProvider.cs" />
+    <Compile Include="OmniXAML\Source\OmniXaml\TypeConversion\ValueContext.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\TypeFactory.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\TypeFactoryMixin.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\TypeFeatureProvider.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\TypeNotFoundException.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\Typing\AttachableMember.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\Typing\ClrNamespace.cs" />
+    <Compile Include="OmniXAML\Source\OmniXaml\Typing\CommonValueConversion.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\Typing\CoreTypes.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\Typing\DependencyRegistration.cs" />
     <Compile Include="OmniXAML\Source\OmniXaml\Typing\DependencyRegistrations.cs" />

src/Markup/Perspex.Markup.Xaml/Templates/TemplateContent.cs

@@ -3,6 +3,7 @@
 
 using System.Collections.Generic;
 using OmniXaml;
+using OmniXaml.ObjectAssembler;
 using Perspex.Controls;
 using Perspex.Markup.Xaml.Context;
 
@@ -21,7 +22,9 @@ namespace Perspex.Markup.Xaml.Templates
 
         public Control Load()
         {
-            var assembler = new PerspexObjectAssembler(runtimeTypeSource);
+            var assembler = new PerspexObjectAssembler(
+                runtimeTypeSource,
+                new TopDownValueContext());
 
             foreach (var xamlNode in nodes)
             {

src/Perspex.Controls/Platform/ITopLevelImpl.cs

@@ -22,6 +22,11 @@ namespace Perspex.Platform
         /// </summary>
         Size ClientSize { get; set; }
 
+        /// <summary>
+        /// Gets the scaling factor for the window.
+        /// </summary>
+        double Scaling { get; }
+
         /// <summary>
         /// Gets the platform window handle.
         /// </summary>
@@ -57,6 +62,11 @@ namespace Perspex.Platform
         /// </summary>
         Action<Size> Resized { get; set; }
 
+        /// <summary>
+        /// Gets or sets a method called when the window's scaling changes.
+        /// </summary>
+        Action<double> ScalingChanged { get; set; }
+
         /// <summary>
         /// Activates the window.
         /// </summary>

src/Perspex.Controls/Platform/PlatformManager.cs

@@ -39,9 +39,6 @@ namespace Perspex.Controls.Platform
             _designerScalingFactor = factor;
         }
 
-        static double RenderScalingFactor => (GetSettings()?.RenderScalingFactor ?? 1)*_designerScalingFactor;
-        static double LayoutScalingFactor => (GetSettings()?.LayoutScalingFactor ?? 1) * _designerScalingFactor;
-
         class RenderTargetDecorator : IRenderTarget
         {
             private readonly IRenderTarget _target;
@@ -62,7 +59,7 @@ namespace Perspex.Controls.Platform
             {
                 var cs = _window.ClientSize;
                 var ctx = _target.CreateDrawingContext();
-                var factor = RenderScalingFactor;
+                var factor = _window.Scaling;
                 if (factor != 1)
                 {
                     ctx.PushPostTransform(Matrix.CreateScale(factor, factor));
@@ -79,7 +76,6 @@ namespace Perspex.Controls.Platform
             private readonly IPopupImpl _popup;
 
             public ITopLevelImpl TopLevel => _tl;
-            double ScalingFactor => LayoutScalingFactor;
 
             public WindowDecorator(ITopLevelImpl tl)
             {
@@ -93,12 +89,12 @@ namespace Perspex.Controls.Platform
 
             private void OnResized(Size size)
             {
-                Resized?.Invoke(size/ScalingFactor);
+                Resized?.Invoke(size/Scaling);
             }
 
             private void OnPaint(Rect rc)
             {
-                var f = ScalingFactor;
+                var f = Scaling;
                 Paint?.Invoke(new Rect(rc.X/f, rc.Y/f, rc.Width/f, rc.Height/f));
             }
 
@@ -106,35 +102,35 @@ namespace Perspex.Controls.Platform
             {
                 var mouseEvent = obj as RawMouseEventArgs;
                 if (mouseEvent != null)
-                    mouseEvent.Position /= ScalingFactor;
+                    mouseEvent.Position /= Scaling;
                 //TODO: Transform event coordinates
                 Input?.Invoke(obj);
             }
 
             public Point PointToClient(Point point)
             {
-                return _tl.PointToClient(point / ScalingFactor) * ScalingFactor;
+                return _tl.PointToClient(point / Scaling) * Scaling;
             }
 
             public Point PointToScreen(Point point)
             {
-                return _tl.PointToScreen(point * ScalingFactor) / ScalingFactor;
+                return _tl.PointToScreen(point * Scaling) / Scaling;
             }
 
             public void Invalidate(Rect rc)
             {
-                var f = ScalingFactor;
+                var f = Scaling;
                 _tl.Invalidate(new Rect(rc.X*f, rc.Y*f, (rc.Width + 1)*f, (rc.Height + 1)*f));
             } 
 
             public Size ClientSize
             {
-                get { return _tl.ClientSize/ScalingFactor; }
-                set { _tl.ClientSize = value*ScalingFactor; }
+                get { return _tl.ClientSize/Scaling; }
+                set { _tl.ClientSize = value*Scaling; }
             }
 
-            public Size MaxClientSize => _window.MaxClientSize/ScalingFactor;
-
+            public Size MaxClientSize => _window.MaxClientSize/Scaling;
+            public double Scaling => _tl.Scaling;
             public Action<RawInputEventArgs> Input { get; set; }
             public Action<Rect> Paint { get; set; }
             public Action<Size> Resized { get; set; }
@@ -163,6 +159,12 @@ namespace Perspex.Controls.Platform
                 set { _window.WindowState = value; }
             }
 
+            public Action<double> ScalingChanged
+            {
+                get { return _tl.ScalingChanged; }
+                set { _tl.ScalingChanged = value; }
+            }
+
             public void Dispose() => _tl.Dispose();
 
             public IPlatformHandle Handle => _tl.Handle;

src/Perspex.Controls/TopLevel.cs

@@ -12,6 +12,7 @@ using Perspex.Layout;
 using Perspex.Platform;
 using Perspex.Rendering;
 using Perspex.Styling;
+using Perspex.VisualTree;
 
 namespace Perspex.Controls
 {
@@ -99,6 +100,7 @@ namespace Perspex.Controls
             PlatformImpl.Closed = HandleClosed;
             PlatformImpl.Input = HandleInput;
             PlatformImpl.Resized = HandleResized;
+            PlatformImpl.ScalingChanged = HandleScalingChanged;
 
             _keyboardNavigationHandler?.SetOwner(this);
             _accessKeyHandler?.SetOwner(this);
@@ -198,6 +200,9 @@ namespace Perspex.Controls
         /// <inheritdoc/>
         Size ILayoutRoot.MaxClientSize => Size.Infinity;
 
+        /// <inheritdoc/>
+        double ILayoutRoot.LayoutScaling => PlatformImpl.Scaling;
+
         IStyleHost IStyleHost.StylingParent
         {
             get { return PerspexLocator.Current.GetService<IGlobalStyles>(); }
@@ -279,6 +284,19 @@ namespace Perspex.Controls
             PlatformImpl.Invalidate(new Rect(clientSize));
         }
 
+        /// <summary>
+        /// Handles a window scaling change notification from 
+        /// <see cref="ITopLevelImpl.ScalingChanged"/>.
+        /// </summary>
+        /// <param name="scaling">The window scaling.</param>
+        protected virtual void HandleScalingChanged(double scaling)
+        {
+            foreach (ILayoutable control in this.GetSelfAndVisualDescendents())
+            {
+                control.InvalidateMeasure();
+            }
+        }
+
         /// <inheritdoc/>
         protected override void OnAttachedToVisualTree(VisualTreeAttachmentEventArgs e)
         {

src/Perspex.Input/Perspex.Input.csproj

@@ -102,7 +102,6 @@
     <Compile Include="Navigation\FocusExtensions.cs" />
     <Compile Include="Navigation\DirectionalNavigation.cs" />
     <Compile Include="Navigation\TabNavigation.cs" />
-    <Compile Include="Platform\IPlatformSettings.cs" />
     <Compile Include="PointerWheelEventArgs.cs" />
     <Compile Include="Raw\RawMouseWheelEventArgs.cs" />
     <Compile Include="Raw\RawSizeEventArgs.cs" />

src/Perspex.Layout/ILayoutRoot.cs

@@ -17,5 +17,10 @@ namespace Perspex.Layout
         /// The maximum client size available.
         /// </summary>
         Size MaxClientSize { get; }
+
+        /// <summary>
+        /// The scaling factor to use in layout.
+        /// </summary>
+        double LayoutScaling { get; }
     }
 }

src/Perspex.Layout/Layoutable.cs

@@ -3,6 +3,7 @@
 
 using System;
 using System.Linq;
+using Perspex.Platform;
 using Perspex.VisualTree;
 using Serilog;
 using Serilog.Core.Enrichers;
@@ -386,6 +387,7 @@ namespace Perspex.Layout
                 IsMeasureValid = false;
                 IsArrangeValid = false;
                 LayoutManager.Instance?.InvalidateMeasure(this);
+                InvalidateVisual();
             }
         }
 
@@ -400,6 +402,7 @@ namespace Perspex.Layout
 
                 IsArrangeValid = false;
                 LayoutManager.Instance?.InvalidateArrange(this);
+                InvalidateVisual();
             }
         }
 
@@ -466,6 +469,7 @@ namespace Perspex.Layout
                     .Deflate(margin);
 
                 var measured = MeasureOverride(constrained);
+
                 var width = measured.Width;
                 var height = measured.Height;
 
@@ -485,6 +489,13 @@ namespace Perspex.Layout
                 height = Math.Min(height, MaxHeight);
                 height = Math.Max(height, MinHeight);
 
+                if (UseLayoutRounding)
+                {
+                    var scale = GetLayoutScale();
+                    width = Math.Ceiling(width * scale) / scale;
+                    height = Math.Ceiling(height * scale) / scale;
+                }
+
                 return NonNegative(new Size(width, height).Inflate(margin));
             }
             else
@@ -510,12 +521,6 @@ namespace Perspex.Layout
                 height = Math.Max(height, child.DesiredSize.Height);
             }
 
-            if (UseLayoutRounding)
-            {
-                width = Math.Ceiling(width);
-                height = Math.Ceiling(height);
-            }
-
             return new Size(width, height);
         }
 
@@ -537,6 +542,7 @@ namespace Perspex.Layout
                     Math.Max(0, finalRect.Width - Margin.Left - Margin.Right),
                     Math.Max(0, finalRect.Height - Margin.Top - Margin.Bottom));
                 var size = sizeMinusMargins;
+                var scale = GetLayoutScale();
 
                 if (HorizontalAlignment != HorizontalAlignment.Stretch)
                 {
@@ -553,11 +559,11 @@ namespace Perspex.Layout
                 if (UseLayoutRounding)
                 {
                     size = new Size(
-                        Math.Ceiling(size.Width), 
-                        Math.Ceiling(size.Height));
+                        Math.Ceiling(size.Width * scale) / scale, 
+                        Math.Ceiling(size.Height * scale) / scale);
                     sizeMinusMargins = new Size(
-                        Math.Ceiling(sizeMinusMargins.Width), 
-                        Math.Ceiling(sizeMinusMargins.Height));
+                        Math.Ceiling(sizeMinusMargins.Width * scale) / scale, 
+                        Math.Ceiling(sizeMinusMargins.Height * scale) / scale);
                 }
 
                 size = ArrangeOverride(size).Constrain(size);
@@ -586,8 +592,8 @@ namespace Perspex.Layout
 
                 if (UseLayoutRounding)
                 {
-                    originX = Math.Floor(originX);
-                    originY = Math.Floor(originY);
+                    originX = Math.Floor(originX * scale) / scale;
+                    originY = Math.Floor(originY * scale) / scale;
                 }
 
                 Bounds = new Rect(originX, originY, size.Width, size.Height);
@@ -666,5 +672,17 @@ namespace Perspex.Layout
         {
             return new Size(Math.Max(size.Width, 0), Math.Max(size.Height, 0));
         }
+
+        private double GetLayoutScale()
+        {
+            var result =  (VisualRoot as ILayoutRoot)?.LayoutScaling ?? 1.0;
+
+            if (result == 0 || double.IsNaN(result) || double.IsInfinity(result))
+            {
+                throw new Exception($"Invalid LayoutScaling returned from {VisualRoot.GetType()}");
+            }
+
+            return result;
+        }
     }
 }

src/Perspex.SceneGraph/Perspex.SceneGraph.csproj

@@ -108,6 +108,7 @@
     <Compile Include="Media\TileBrush.cs" />
     <Compile Include="Media\ImageBush.cs" />
     <Compile Include="Media\VisualBrush.cs" />
+    <Compile Include="Platform\IPlatformSettings.cs" />
     <Compile Include="RelativePoint.cs" />
     <Compile Include="Platform\IFormattedTextImpl.cs" />
     <Compile Include="Platform\IBitmapImpl.cs" />

src/Perspex.Input/Platform/IPlatformSettings.cs → src/Perspex.SceneGraph/Platform/IPlatformSettings.cs

@@ -10,9 +10,5 @@ namespace Perspex.Platform
         Size DoubleClickSize { get; }
 
         TimeSpan DoubleClickTime { get; }
-
-        double RenderScalingFactor { get; }
-
-        double LayoutScalingFactor { get; }
     }
 }

src/Windows/Perspex.Direct2D1/RenderTarget.cs

@@ -76,14 +76,16 @@ namespace Perspex.Direct2D1
         /// </summary>
         public Factory Direct2DFactory
         {
-            get; }
+            get;
+        }
 
         /// <summary>
         /// Gets the DirectWrite factory.
         /// </summary>
         public DwFactory DirectWriteFactory
         {
-            get; }
+            get;
+        }
 
         /// <summary>
         /// Creates a drawing context for a rendering session.

src/Windows/Perspex.Win32/Interop/UnmanagedMethods.cs

@@ -490,6 +490,7 @@ namespace Perspex.Win32.Interop
             WM_WTSSESSION_CHANGE = 0x02B1,
             WM_TABLET_FIRST = 0x02c0,
             WM_TABLET_LAST = 0x02df,
+            WM_DPICHANGED = 0x02E0,
             WM_CUT = 0x0300,
             WM_COPY = 0x0301,
             WM_PASTE = 0x0302,
@@ -621,6 +622,9 @@ namespace Perspex.Win32.Interop
         [DllImport("user32.dll")]
         public static extern bool IsWindowUnicode(IntPtr hWnd);
 
+        [DllImport("user32.dll")]
+        public static extern bool IsWindowVisible(IntPtr hWnd);
+
         [DllImport("user32.dll")]
         public static extern bool KillTimer(IntPtr hWnd, IntPtr uIDEvent);
 
@@ -729,7 +733,6 @@ namespace Perspex.Win32.Interop
         [DllImport("kernel32.dll", CharSet = CharSet.Auto, ExactSpelling = true)]
         public static extern IntPtr GlobalLock(IntPtr handle);
 
-
         [DllImport("kernel32.dll", CharSet = CharSet.Auto, ExactSpelling = true)]
         public static extern bool GlobalUnlock(IntPtr handle);
 
@@ -748,6 +751,43 @@ namespace Perspex.Win32.Interop
         [DllImport("comdlg32.dll")]
         public static extern int CommDlgExtendedError();
 
+        [DllImport("shcore.dll")]
+        public static extern void SetProcessDpiAwareness(PROCESS_DPI_AWARENESS value);
+
+        [DllImport("shcore.dll")]
+        public static extern long GetDpiForMonitor(IntPtr hmonitor, MONITOR_DPI_TYPE dpiType, out uint dpiX, out uint dpiY);
+
+        [DllImport("shcore.dll")]
+        public static extern void GetScaleFactorForMonitor(IntPtr hMon, out uint pScale);
+
+        [DllImport("user32.dll")]
+        public static extern IntPtr MonitorFromPoint(POINT pt, MONITOR dwFlags);
+
+        [DllImport("user32.dll")]
+        public static extern IntPtr MonitorFromWindow(IntPtr hwnd, MONITOR dwFlags);
+
+        public enum MONITOR
+        {
+            MONITOR_DEFAULTTONULL = 0x00000000,
+            MONITOR_DEFAULTTOPRIMARY = 0x00000001,
+            MONITOR_DEFAULTTONEAREST = 0x00000002,
+        }
+
+        public enum PROCESS_DPI_AWARENESS
+        {
+            PROCESS_DPI_UNAWARE = 0,
+            PROCESS_SYSTEM_DPI_AWARE = 1,
+            PROCESS_PER_MONITOR_DPI_AWARE = 2
+        }
+
+        public enum MONITOR_DPI_TYPE
+        {
+            MDT_EFFECTIVE_DPI = 0,
+            MDT_ANGULAR_DPI = 1,
+            MDT_RAW_DPI = 2,
+            MDT_DEFAULT = MDT_EFFECTIVE_DPI
+        } 
+
         public enum ClipboardFormat
         {
             CF_TEXT = 1,

src/Windows/Perspex.Win32/Win32Platform.cs

@@ -22,15 +22,15 @@ namespace Perspex.Win32
     {
         private static readonly Win32Platform s_instance = new Win32Platform();
         private static Thread _uiThread;
-
         private UnmanagedMethods.WndProc _wndProcDelegate;
-
         private IntPtr _hwnd;
-
         private readonly List<Delegate> _delegates = new List<Delegate>();
 
         public Win32Platform()
         {
+            // Declare that this process is aware of per monitor DPI 
+            UnmanagedMethods.SetProcessDpiAwareness(UnmanagedMethods.PROCESS_DPI_AWARENESS.PROCESS_PER_MONITOR_DPI_AWARE);
+
             CreateMessageWindow();
         }
 
@@ -39,8 +39,6 @@ namespace Perspex.Win32
             UnmanagedMethods.GetSystemMetrics(UnmanagedMethods.SystemMetric.SM_CYDOUBLECLK));
 
         public TimeSpan DoubleClickTime => TimeSpan.FromMilliseconds(UnmanagedMethods.GetDoubleClickTime());
-        public double RenderScalingFactor { get; } = 1;
-        public double LayoutScalingFactor { get; } = 1;
 
         public static void Initialize()
         {

src/Windows/Perspex.Win32/WindowImpl.cs

@@ -26,18 +26,14 @@ namespace Perspex.Win32
             IntPtr.Zero, new IntPtr((int)UnmanagedMethods.Cursor.IDC_ARROW));
 
         private UnmanagedMethods.WndProc _wndProcDelegate;
-
         private string _className;
-
         private IntPtr _hwnd;
-
         private IInputRoot _owner;
-
         private bool _trackingMouse;
-
         private bool _isActive;
-
         private bool _decorated = true;
+        private double _scaling = 1;
+        private WindowState _showWindowState;
 
         public WindowImpl()
         {
@@ -57,6 +53,8 @@ namespace Perspex.Win32
 
         public Action<Size> Resized { get; set; }
 
+        public Action<double> ScalingChanged { get; set; }
+
         public Thickness BorderThickness
         {
             get
@@ -103,6 +101,8 @@ namespace Perspex.Win32
             }
         }
 
+        public double Scaling => _scaling;
+
         public IPlatformHandle Handle
         {
             get;
@@ -146,24 +146,14 @@ namespace Perspex.Win32
 
             set
             {
-                UnmanagedMethods.ShowWindowCommand command;
-
-                switch (value)
+                if (UnmanagedMethods.IsWindowVisible(_hwnd))
                 {
-                    case WindowState.Minimized:
-                        command = UnmanagedMethods.ShowWindowCommand.Minimize;
-                        break;
-                    case WindowState.Maximized:
-                        command = UnmanagedMethods.ShowWindowCommand.Maximize;
-                        break;
-                    case WindowState.Normal:
-                        command = UnmanagedMethods.ShowWindowCommand.Restore;
-                        break;
-                    default:
-                        throw new ArgumentException("Invalid WindowState.");
+                    ShowWindow(value);
+                }
+                else
+                {
+                    _showWindowState = value;
                 }
-
-                UnmanagedMethods.ShowWindow(_hwnd, command);
             }
         }
 
@@ -268,7 +258,7 @@ namespace Perspex.Win32
 
         public virtual void Show()
         {
-            UnmanagedMethods.ShowWindow(_hwnd, UnmanagedMethods.ShowWindowCommand.Normal);
+            ShowWindow(_showWindowState);
         }
 
         public void BeginMoveDrag()
@@ -410,6 +400,12 @@ namespace Perspex.Win32
 
                     return IntPtr.Zero;
 
+                case UnmanagedMethods.WindowsMessage.WM_DPICHANGED:
+                    var dpi = (int)wParam & 0xffff;
+                    _scaling = dpi / 96.0;
+                    ScalingChanged?.Invoke(_scaling);
+                    break;
+
                 case UnmanagedMethods.WindowsMessage.WM_KEYDOWN:
                 case UnmanagedMethods.WindowsMessage.WM_SYSKEYDOWN:
                     e = new RawKeyEventArgs(
@@ -608,6 +604,20 @@ namespace Perspex.Win32
             }
 
             Handle = new PlatformHandle(_hwnd, PlatformConstants.WindowHandleType);
+
+            var monitor = UnmanagedMethods.MonitorFromWindow(
+                _hwnd, 
+                UnmanagedMethods.MONITOR.MONITOR_DEFAULTTONEAREST);
+
+            uint dpix, dpiy;
+            if (UnmanagedMethods.GetDpiForMonitor(
+                    monitor, 
+                    UnmanagedMethods.MONITOR_DPI_TYPE.MDT_EFFECTIVE_DPI, 
+                    out dpix, 
+                    out dpiy) == 0)
+            {
+                _scaling = dpix / 96.0;
+            }
         }
 
         private Point PointFromLParam(IntPtr lParam)
@@ -621,5 +631,28 @@ namespace Perspex.Win32
             UnmanagedMethods.ScreenToClient(_hwnd, ref p);
             return new Point(p.X, p.Y);
         }
+
+        private void ShowWindow(WindowState state)
+        {
+            UnmanagedMethods.ShowWindowCommand command;
+
+            switch (state)
+            {
+                case WindowState.Minimized:
+                    command = UnmanagedMethods.ShowWindowCommand.Minimize;
+                    break;
+                case WindowState.Maximized:
+                    command = UnmanagedMethods.ShowWindowCommand.Maximize;
+                    break;
+                case WindowState.Normal:
+                    command = UnmanagedMethods.ShowWindowCommand.Restore;
+                    break;
+                default:
+                    throw new ArgumentException("Invalid WindowState.");
+            }
+
+            UnmanagedMethods.ShowWindow(_hwnd, command);
+        }
+
     }
 }

src/iOS/Perspex.iOS/PerspexView.cs

@@ -70,10 +70,12 @@ namespace Perspex.iOS
         public Action<RawInputEventArgs> Input { get; set; }
         public Action<Rect> Paint { get; set; }
         public Action<Size> Resized { get; set; }
-
+        public Action<double> ScalingChanged { get; set; }
 
         public IPlatformHandle Handle => PerspexPlatformHandle;
 
+        public double Scaling => 1;
+
         public WindowState WindowState
         {
             get { return WindowState.Normal; }

tests/Perspex.Controls.UnitTests/TopLevelTests.cs

@@ -88,6 +88,7 @@ namespace Perspex.Controls.UnitTests
                 var impl = new Mock<ITopLevelImpl>();
                 impl.SetupProperty(x => x.ClientSize);
                 impl.SetupProperty(x => x.Resized);
+                impl.SetupGet(x => x.Scaling).Returns(1);
 
                 var target = new TestTopLevel(impl.Object)
                 {
@@ -110,9 +111,9 @@ namespace Perspex.Controls.UnitTests
         {
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
-                var impl = new Mock<ITopLevelImpl>();
+                var impl = Mock.Of<ITopLevelImpl>(x => x.Scaling == 1);
 
-                var target = new TestTopLevel(impl.Object)
+                var target = new TestTopLevel(impl)
                 {
                     Template = CreateTemplate(),
                     Content = new TextBlock
@@ -124,7 +125,7 @@ namespace Perspex.Controls.UnitTests
 
                 LayoutManager.Instance.ExecuteInitialLayoutPass(target);
 
-                impl.VerifySet(x => x.ClientSize = new Size(321, 432));
+                Mock.Get(impl).VerifySet(x => x.ClientSize = new Size(321, 432));
             }
         }
 

tests/Perspex.Controls.UnitTests/WindowingPlatformMock.cs

@@ -17,7 +17,7 @@ namespace Perspex.Controls.UnitTests
 
         public IWindowImpl CreateWindow()
         {
-            return _windowImpl?.Invoke() ?? new Mock<IWindowImpl>().Object;
+            return _windowImpl?.Invoke() ?? Mock.Of<IWindowImpl>(x => x.Scaling == 1);
         }
 
         public IWindowImpl CreateEmbeddableWindow()
@@ -25,6 +25,6 @@ namespace Perspex.Controls.UnitTests
             throw new NotImplementedException();
         }
 
-        public IPopupImpl CreatePopup() => _popupImpl?.Invoke() ?? new Mock<IPopupImpl>().Object;
+        public IPopupImpl CreatePopup() => _popupImpl?.Invoke() ?? Mock.Of<IPopupImpl>(x => x.Scaling == 1);
     }
 }

tests/Perspex.Layout.UnitTests/FullLayoutTests.cs

@@ -142,6 +142,7 @@ namespace Perspex.Layout.UnitTests
 
             windowImpl.SetupProperty(x => x.ClientSize);
             windowImpl.Setup(x => x.MaxClientSize).Returns(new Size(1024, 1024));
+            windowImpl.SetupGet(x => x.Scaling).Returns(1);
 
             PerspexLocator.CurrentMutable
                 .Bind<IAssetLoader>().ToConstant(new AssetLoader())

tests/Perspex.Layout.UnitTests/TestLayoutRoot.cs

@@ -19,5 +19,6 @@ namespace Perspex.Layout.UnitTests
         }
 
         public Size MaxClientSize => Size.Infinity;
+        public double LayoutScaling => 1;
     }
 }

tests/Perspex.Markup.Xaml.UnitTests/Converters/PerspexPropertyConverterTest.cs

@@ -56,9 +56,9 @@ namespace Perspex.Markup.Xaml.UnitTests.Converters
             Assert.Equal(AttachedOwner.AttachedProperty, result);
         }
 
-        private ITypeConverterContext CreateContext(Style style = null)
+        private IValueContext CreateContext(Style style = null)
         {
-            var context = new Mock<ITypeConverterContext>();
+            var context = new Mock<IValueContext>();
             var topDownValueContext = new Mock<ITopDownValueContext>();
             var typeRepository = new Mock<ITypeRepository>();
             var featureProvider = new Mock<ITypeFeatureProvider>();

tests/Perspex.UnitTests/MockWindowingPlatform.cs

@@ -17,7 +17,7 @@ namespace Perspex.UnitTests
 
         public IWindowImpl CreateWindow()
         {
-            return _windowImpl?.Invoke() ?? Mock.Of<IWindowImpl>();
+            return _windowImpl?.Invoke() ?? Mock.Of<IWindowImpl>(x => x.Scaling == 1);
         }
 
         public IWindowImpl CreateEmbeddableWindow()

tests/Perspex.UnitTests/TestRoot.cs

@@ -34,6 +34,8 @@ namespace Perspex.UnitTests
 
         public Size MaxClientSize => Size.Infinity;
 
+        public double LayoutScaling => 1;
+
         public ILayoutManager LayoutManager => PerspexLocator.Current.GetService<ILayoutManager>();
 
         public IRenderTarget RenderTarget => null;

tests/Perspex.UnitTests/TestTemplatedRoot.cs

@@ -37,6 +37,8 @@ namespace Perspex.UnitTests
 
         public Size MaxClientSize => Size.Infinity;
 
+        public double LayoutScaling => 1;
+
         public ILayoutManager LayoutManager => PerspexLocator.Current.GetService<ILayoutManager>();
 
         public IRenderTarget RenderTarget => null;