Allow GradientBrushes in XAML.

samples/XamlTestApplication/Views/MainWindow.xaml

@@ -2,6 +2,7 @@
         xmlns="https://github.com/perspex"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
         Title="Perspex Test Application" Height="350" Width="525">
+   
     <Grid RowDefinitions="Auto,*">
         <TabControl Grid.Row="1">
             <TabItem Header="Buttons">
@@ -101,7 +102,13 @@
                         <RowDefinition />
                         <RowDefinition Height="Auto" />
                     </Grid.RowDefinitions>
-                    <Border Width="100" Height="100" Background="Crimson">
+                    <Border Width="100" Height="100">
+                        <Border.Background>
+                            <LinearGradientBrush StartPoint="0,0" EndPoint="1,1">
+                                <GradientStop Color="Red" Offset="0"/>
+                                <GradientStop Color="Green" Offset="1"/>
+                            </LinearGradientBrush>
+                        </Border.Background>
                         <TextBox HorizontalAlignment="Center" VerticalAlignment="Center" Text="hello!"></TextBox>
                     </Border>
                     <Border Grid.Row="0" Grid.Column="1" Background="Coral" HorizontalAlignment="Center"

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

@@ -77,9 +77,11 @@ namespace Perspex.Markup.Xaml.Context
             {
                 new TypeConverterRegistration(typeof(Bitmap), new BitmapTypeConverter()),
                 new TypeConverterRegistration(typeof(Brush), new BrushTypeConverter()),
+                new TypeConverterRegistration(typeof(Color), new ColorTypeConverter()),
                 new TypeConverterRegistration(typeof(Classes), new ClassesTypeConverter()),
                 new TypeConverterRegistration(typeof(ColumnDefinitions), new ColumnDefinitionsTypeConverter()),
                 new TypeConverterRegistration(typeof(GridLength), new GridLengthTypeConverter()),
+                new TypeConverterRegistration(typeof(Point), new PointTypeConverter()),
                 new TypeConverterRegistration(typeof(PerspexProperty), new PerspexPropertyTypeConverter()),
                 new TypeConverterRegistration(typeof(RowDefinitions), new RowDefinitionsTypeConverter()),
                 new TypeConverterRegistration(typeof(Thickness), new ThicknessTypeConverter()),
@@ -98,6 +100,7 @@ namespace Perspex.Markup.Xaml.Context
                 new ContentPropertyDefinition(typeof(ContentControl), "Content"),
                 new ContentPropertyDefinition(typeof(Decorator), "Child"),
                 new ContentPropertyDefinition(typeof(ItemsControl), "Items"),
+                new ContentPropertyDefinition(typeof(GradientBrush), "GradientStops"),
                 new ContentPropertyDefinition(typeof(Panel), "Children"),
                 new ContentPropertyDefinition(typeof(Style), "Setters"),
                 new ContentPropertyDefinition(typeof(TextBlock), "Text"),

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

@@ -0,0 +1,33 @@
+// Copyright (c) The Perspex Project. All rights reserved.
+// Licensed under the MIT license. See licence.md file in the project root for full license information.
+
+using System;
+using System.Globalization;
+using OmniXaml.TypeConversion;
+using Perspex.Media;
+
+namespace Perspex.Markup.Xaml.Converters
+{
+    public class ColorTypeConverter : ITypeConverter
+    {
+        public bool CanConvertFrom(IXamlTypeConverterContext context, Type sourceType)
+        {
+            return sourceType == typeof(string);
+        }
+
+        public bool CanConvertTo(IXamlTypeConverterContext context, Type destinationType)
+        {
+            return false;
+        }
+
+        public object ConvertFrom(IXamlTypeConverterContext context, CultureInfo culture, object value)
+        {
+            return Color.Parse((string)value);
+        }
+
+        public object ConvertTo(IXamlTypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        {
+            throw new NotImplementedException();
+        }
+    }
+}

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

@@ -0,0 +1,32 @@
+// Copyright (c) The Perspex Project. All rights reserved.
+// Licensed under the MIT license. See licence.md file in the project root for full license information.
+
+using System;
+using System.Globalization;
+using OmniXaml.TypeConversion;
+
+namespace Perspex.Markup.Xaml.Converters
+{
+    public class PointTypeConverter : ITypeConverter
+    {
+        public bool CanConvertFrom(IXamlTypeConverterContext context, Type sourceType)
+        {
+            return sourceType == typeof(string);
+        }
+
+        public bool CanConvertTo(IXamlTypeConverterContext context, Type destinationType)
+        {
+            return false;
+        }
+
+        public object ConvertFrom(IXamlTypeConverterContext context, CultureInfo culture, object value)
+        {
+            return Point.Parse((string)value, culture);
+        }
+
+        public object ConvertTo(IXamlTypeConverterContext context, CultureInfo culture, object value, Type destinationType)
+        {
+            throw new NotImplementedException();
+        }
+    }
+}

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

@@ -38,6 +38,8 @@
     <Compile Include="..\..\Shared\SharedAssemblyInfo.cs">
       <Link>Properties\SharedAssemblyInfo.cs</Link>
     </Compile>
+    <Compile Include="Converters\ColorTypeConverter.cs" />
+    <Compile Include="Converters\PointTypeConverter.cs" />
     <Compile Include="Converters\ClassesTypeConverter.cs" />
     <Compile Include="Converters\RowDefinitionsTypeConverter.cs" />
     <Compile Include="Converters\ColumnDefinitionsTypeConverter.cs" />

src/Perspex.SceneGraph/Point.cs

@@ -1,7 +1,9 @@
 // Copyright (c) The Perspex Project. All rights reserved.
 // Licensed under the MIT license. See licence.md file in the project root for full license information.
 
+using System;
 using System.Globalization;
+using System.Linq;
 
 namespace Perspex
 {
@@ -139,6 +141,28 @@ namespace Perspex
                 (point.X * matrix.M12) + (point.Y * matrix.M22) + matrix.M32);
         }
 
+        /// <summary>
+        /// Parses a <see cref="Point"/> string.
+        /// </summary>
+        /// <param name="s">The string.</param>
+        /// <param name="culture">The current culture.</param>
+        /// <returns>The <see cref="Thickness"/>.</returns>
+        public static Point Parse(string s, CultureInfo culture)
+        {
+            var parts = s.Split(new[] { ',', ' ' }, StringSplitOptions.RemoveEmptyEntries)
+                .Select(x => x.Trim())
+                .ToList();
+
+            if (parts.Count == 2)
+            {
+                return new Point(double.Parse(parts[0], culture), double.Parse(parts[1], culture));
+            }
+            else
+            {
+                throw new FormatException("Invalid Thickness.");
+            }
+        }
+
         /// <summary>
         /// Checks for equality between a point and an object.
         /// </summary>

src/Perspex.SceneGraph/Properties/AssemblyInfo.cs

@@ -2,5 +2,7 @@
 // Licensed under the MIT license. See licence.md file in the project root for full license information.
 
 using System.Reflection;
+using Perspex.Metadata;
 
 [assembly: AssemblyTitle("Perspex.SceneGraph")]
+[assembly: XmlnsDefinition("https://github.com/perspex", "Perspex.Media")]

src/Perspex.SceneGraph/Thickness.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 System.Globalization;
 using System.Linq;
 
 namespace Perspex
@@ -168,8 +169,9 @@ namespace Perspex
         /// Parses a <see cref="Thickness"/> string.
         /// </summary>
         /// <param name="s">The string.</param>
+        /// <param name="culture">The current culture.</param>
         /// <returns>The <see cref="Thickness"/>.</returns>
-        public static Thickness Parse(string s)
+        public static Thickness Parse(string s, CultureInfo culture)
         {
             var parts = s.Split(new[] { ',', ' ' }, StringSplitOptions.RemoveEmptyEntries)
                 .Select(x => x.Trim())
@@ -178,17 +180,17 @@ namespace Perspex
             switch (parts.Count)
             {
                 case 1:
-                    var uniform = double.Parse(parts[0]);
+                    var uniform = double.Parse(parts[0], culture);
                     return new Thickness(uniform);
                 case 2:
-                    var horizontal = double.Parse(parts[0]);
-                    var vertical = double.Parse(parts[1]);
+                    var horizontal = double.Parse(parts[0], culture);
+                    var vertical = double.Parse(parts[1], culture);
                     return new Thickness(horizontal, vertical);
                 case 4:
-                    var left = double.Parse(parts[0]);
-                    var top = double.Parse(parts[1]);
-                    var right = double.Parse(parts[2]);
-                    var bottom = double.Parse(parts[3]);
+                    var left = double.Parse(parts[0], culture);
+                    var top = double.Parse(parts[1], culture);
+                    var right = double.Parse(parts[2], culture);
+                    var bottom = double.Parse(parts[3], culture);
                     return new Thickness(left, top, right, bottom);
             }