Implemented DashStyle

src/Gtk/Perspex.Cairo/Media/DrawingContext.cs

@@ -2,13 +2,14 @@
 // Licensed under the MIT license. See licence.md file in the project root for full license information.
 
 using System;
+using System.Linq;
 using System.Reactive.Disposables;
 using Perspex.Cairo.Media.Imaging;
 using Perspex.Media;
-using IBitmap = Perspex.Media.Imaging.IBitmap;
 
 namespace Perspex.Cairo.Media
 {
+    using Perspex.Media.Imaging;
     using Cairo = global::Cairo;
 
     /// <summary>
@@ -77,9 +78,9 @@ namespace Perspex.Cairo.Media
         public void DrawLine(Pen pen, Point p1, Point p2)
         {
             var size = new Rect(p1, p2).Size;
+            
+            SetPen(pen, size);
 
-            SetBrush(pen.Brush, size);
-            _context.LineWidth = pen.Thickness;
             _context.MoveTo(p1.ToCairo());
             _context.LineTo(p2.ToCairo());
             _context.Stroke();
@@ -139,9 +140,9 @@ namespace Perspex.Cairo.Media
         public void DrawText(Brush foreground, Point origin, FormattedText text)
         {
             var layout = ((FormattedTextImpl)text.PlatformImpl).Layout;
-            SetBrush(foreground, new Size(0, 0));
-
             _context.MoveTo(origin.X, origin.Y);
+
+            SetBrush(foreground, new Size(0, 0));
             Pango.CairoHelper.ShowLayout(_context, layout);
         }
 
@@ -195,7 +196,7 @@ namespace Perspex.Cairo.Media
                 _context.Transform(matrix.Invert().ToCairo());
             });
         }
-
+        
         private void SetBrush(Brush brush, Size destinationSize)
         {
             var solid = brush as SolidColorBrush;
@@ -225,7 +226,23 @@ namespace Perspex.Cairo.Media
         private void SetPen(Pen pen, Size destinationSize)
         {
             SetBrush(pen.Brush, destinationSize);
+            if (pen.DashStyle != null)
+            {
+                if (pen.DashStyle.Dashes != null && pen.DashStyle.Dashes.Count > 0)
+                {
+                    var cray = pen.DashStyle.Dashes.ToArray();
+                    _context.SetDash(cray, pen.DashStyle.Offset);
+                }
+            }
+
             _context.LineWidth = pen.Thickness;
+            _context.MiterLimit = pen.MiterLimit;
+
+            // Line caps and joins are currently broken on Cairo. I've defaulted them to sensible defaults for now.
+            // Cairo does not have StartLineCap, EndLineCap, and DashCap properties, whereas Direct2D does. 
+            // TODO: Figure out a solution for this.
+            _context.LineJoin = Cairo.LineJoin.Miter;
+            _context.LineCap = Cairo.LineCap.Butt;
         }
     }
 }

src/Perspex.Controls/Shapes/Shape.cs

@@ -96,7 +96,7 @@ namespace Perspex.Controls.Shapes
 
             if (geometry != null)
             {
-                var pen = new Pen(Stroke, StrokeThickness, StrokeDashArray);
+                var pen = new Pen(Stroke, StrokeThickness, new DashStyle(StrokeDashArray));
                 context.DrawGeometry(Fill, pen, geometry);
             }
         }

src/Perspex.SceneGraph/Media/DashStyle.cs

@@ -0,0 +1,84 @@
+namespace Perspex.Media
+{
+    using Perspex.Animation;
+    using System;
+    using System.Collections.Generic;
+    using System.Linq;
+    using System.Text;
+    using System.Threading.Tasks;
+
+    public class DashStyle : Animatable
+    {
+        private static DashStyle dash;
+        public static DashStyle Dash
+        {
+            get
+            {
+                if (dashDotDot == null)
+                {
+                    dash = new DashStyle(new double[] { 2, 2 }, 1);
+                }
+
+                return dash;
+            }
+        }
+
+
+
+        private static DashStyle dot;
+        public static DashStyle Dot
+        {
+            get
+            {
+                if (dot == null)
+                {
+                    dot = new DashStyle(new double[] { 0, 2 }, 0);
+                }
+
+                return dot;
+            }
+        }
+
+        private static DashStyle dashDot;
+        public static DashStyle DashDot
+        {
+            get
+            {
+                if (dashDot == null)
+                {
+                    dashDot = new DashStyle(new double[] { 2, 2, 0, 2 }, 1);
+                }
+
+                return dashDot;
+            }
+        }
+
+        private static DashStyle dashDotDot;
+        public static DashStyle DashDotDot
+        {
+            get
+            {
+                if (dashDotDot == null)
+                {
+                    dashDotDot = new DashStyle(new double[] { 2, 2, 0, 2, 0, 2 }, 1);
+                }
+
+                return dashDotDot;
+            }
+        }
+
+
+        public DashStyle(IReadOnlyList<double> dashes = null, double offset = 0.0)
+        {
+            this.Dashes = dashes;
+            this.Offset = offset;
+        }
+
+        /// <summary>
+        /// Gets and sets the length of alternating dashes and gaps.
+        /// </summary>
+        public IReadOnlyList<double> Dashes { get; }
+
+        public double Offset { get; }
+    }
+}

src/Perspex.SceneGraph/Media/Pen.cs

@@ -15,12 +15,20 @@ namespace Perspex.Media
         /// </summary>
         /// <param name="brush">The brush used to draw.</param>
         /// <param name="thickness">The stroke thickness.</param>
-        /// <param name="dashArray">The length of alternating dashes and gaps.</param>
-        public Pen(Brush brush, double thickness, IReadOnlyList<double> dashArray = null)
+        public Pen(
+            Brush brush, 
+            double thickness = 1.0,
+            DashStyle dashStyle = null, PenLineCap dashCap = PenLineCap.Flat, PenLineCap startLineCap = PenLineCap.Flat, 
+            PenLineCap endLineCap = PenLineCap.Flat, PenLineJoin lineJoin = PenLineJoin.Miter, double miterLimit = 10.0)
         {
             Brush = brush;
             Thickness = thickness;
-            DashArray = dashArray;
+            StartLineCap = startLineCap;
+            EndLineCap = endLineCap;
+            LineJoin = lineJoin;
+            MiterLimit = miterLimit;
+            DashStyle = dashStyle;
+            DashCap = dashCap;
         }
 
         /// <summary>
@@ -28,12 +36,20 @@ namespace Perspex.Media
         /// </summary>
         /// <param name="color">The stroke color.</param>
         /// <param name="thickness">The stroke thickness.</param>
-        /// <param name="dashArray">The length of alternating dashes and gaps.</param>
-        public Pen(uint color, double thickness, IReadOnlyList<double> dashArray = null)
+        public Pen(
+            uint color, 
+            double thickness = 1.0,
+            DashStyle dashStyle = null, PenLineCap dashCap = PenLineCap.Flat, PenLineCap startLineCap = PenLineCap.Flat,
+            PenLineCap endLineCap = PenLineCap.Flat, PenLineJoin lineJoin = PenLineJoin.Miter, double miterLimit = 10.0)
         {
             Brush = new SolidColorBrush(color);
             Thickness = thickness;
-            DashArray = dashArray;
+            StartLineCap = startLineCap;
+            EndLineCap = endLineCap;
+            LineJoin = lineJoin;
+            MiterLimit = miterLimit;
+            DashStyle = dashStyle;
+            DashCap = dashCap;
         }
 
         /// <summary>
@@ -41,14 +57,21 @@ namespace Perspex.Media
         /// </summary>
         public Brush Brush { get; }
 
-        /// <summary>
-        /// Gets the length of alternating dashes and gaps.
-        /// </summary>
-        public IReadOnlyList<double> DashArray { get; }
-
         /// <summary>
         /// Gets the stroke thickness.
         /// </summary>
-        public double Thickness { get; }
+        public double Thickness { get; } = 1.0;
+
+        public DashStyle DashStyle { get; }
+
+        public PenLineCap DashCap { get; }
+
+        public PenLineCap StartLineCap { get; } = PenLineCap.Flat;
+
+        public PenLineCap EndLineCap { get; } = PenLineCap.Flat;
+
+        public PenLineJoin LineJoin { get; } = PenLineJoin.Miter;
+
+        public double MiterLimit { get; } = 10.0;
     }
 }

src/Perspex.SceneGraph/Media/PenLineCap.cs

@@ -0,0 +1,16 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Perspex.Media
+{
+    public enum PenLineCap
+    {
+        Flat,
+        Round,
+        Square,
+        Triangle
+    }
+}

src/Perspex.SceneGraph/Media/PenLineJoin.cs

@@ -0,0 +1,15 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Perspex.Media
+{
+    public enum PenLineJoin
+    {
+        Bevel,
+        Miter,
+        Round
+    }
+}

src/Perspex.SceneGraph/Perspex.SceneGraph.csproj

@@ -63,11 +63,14 @@
     <Compile Include="Media\BrushMappingMode.cs" />
     <Compile Include="Media\Color.cs" />
     <Compile Include="Media\Colors.cs" />
+    <Compile Include="Media\DashStyle.cs" />
     <Compile Include="Media\MediaExtensions.cs" />
     <Compile Include="Media\GradientBrush.cs" />
     <Compile Include="Media\GradientSpreadMethod.cs" />
     <Compile Include="Media\GradientStop.cs" />
     <Compile Include="Media\LinearGradientBrush.cs" />
+    <Compile Include="Media\PenLineCap.cs" />
+    <Compile Include="Media\PenLineJoin.cs" />
     <Compile Include="Media\TextAlignment.cs" />
     <Compile Include="Media\FontWeight.cs" />
     <Compile Include="Media\FontStyle.cs" />

src/Windows/Perspex.Direct2D1/PrimitiveExtensions.cs

@@ -40,6 +40,29 @@ namespace Perspex.Direct2D1
             else
                 return ExtendMode.Wrap;
         }
+
+        public static SharpDX.Direct2D1.LineJoin ToDirect2D(this Perspex.Media.PenLineJoin lineJoin)
+        {
+            if (lineJoin == Perspex.Media.PenLineJoin.Round)
+                return LineJoin.Round;
+            else if (lineJoin == Perspex.Media.PenLineJoin.Miter)
+                return LineJoin.Miter;
+            else
+                return LineJoin.Bevel;
+        }
+        
+        public static SharpDX.Direct2D1.CapStyle ToDirect2D(this Perspex.Media.PenLineCap lineCap)
+        {
+            if (lineCap == Perspex.Media.PenLineCap.Flat)
+                return CapStyle.Flat;
+            else if (lineCap == Perspex.Media.PenLineCap.Round)
+                return CapStyle.Round;
+            else if (lineCap == Perspex.Media.PenLineCap.Square)
+                return CapStyle.Square;
+            else
+                return CapStyle.Triangle;
+        }
+
         /// <summary>
         /// Converts a pen to a Direct2D stroke style.
         /// </summary>
@@ -48,19 +71,26 @@ namespace Perspex.Direct2D1
         /// <returns>The Direct2D brush.</returns>
         public static StrokeStyle ToDirect2DStrokeStyle(this Perspex.Media.Pen pen, RenderTarget target)
         {
-            if (pen.DashArray != null && pen.DashArray.Count > 0)
+            if (pen.DashStyle != null)
             {
-                var properties = new StrokeStyleProperties
+                if (pen.DashStyle.Dashes != null && pen.DashStyle.Dashes.Count > 0)
                 {
-                    DashStyle = DashStyle.Custom,
-                };
+                    var properties = new StrokeStyleProperties
+                    {
+                        DashStyle = DashStyle.Custom,
+                        DashOffset = (float)pen.DashStyle.Offset,
+                        MiterLimit = (float)pen.MiterLimit,
+                        LineJoin = pen.LineJoin.ToDirect2D(),
+                        StartCap = pen.StartLineCap.ToDirect2D(),
+                        EndCap = pen.EndLineCap.ToDirect2D(),
+                        DashCap = pen.DashCap.ToDirect2D()
+                    };
 
-                return new StrokeStyle(target.Factory, properties, pen.DashArray.Select(x => (float)x).ToArray());
-            }
-            else
-            {
-                return null;
+                    return new StrokeStyle(target.Factory, properties, pen.DashStyle?.Dashes.Select(x => (float)x).ToArray());
+                }
             }
+
+            return null;
         }
 
         /// <summary>