Added bindings for canvas annotations

binding/Binding/SKCanvas.cs

@@ -462,6 +462,47 @@ namespace SkiaSharp
 			SkiaApi.sk_canvas_flush (Handle);
 		}
 
+		public void DrawAnnotation (SKRect rect, string key, SKData value)
+		{
+			SkiaApi.sk_canvas_draw_annotation (Handle, ref rect, Util.GetEncodedText (key, SKTextEncoding.Utf8), value == null ? IntPtr.Zero : value.Handle);
+		}
+
+		public void DrawUrlAnnotation (SKRect rect, SKData value)
+		{
+			SkiaApi.sk_canvas_draw_url_annotation (Handle, ref rect, value == null ? IntPtr.Zero : value.Handle);
+		}
+
+		public SKData DrawUrlAnnotation (SKRect rect, string value)
+		{
+			var data = SKData.FromCString (value);
+			DrawUrlAnnotation (rect, data);
+			return data;
+		}
+
+		public void DrawNamedDestinationAnnotation (SKPoint point, SKData value)
+		{
+			SkiaApi.sk_canvas_draw_named_destination_annotation (Handle, ref point, value == null ? IntPtr.Zero : value.Handle);
+		}
+
+		public SKData DrawNamedDestinationAnnotation (SKPoint point, string value)
+		{
+			var data = SKData.FromCString (value);
+			DrawNamedDestinationAnnotation (point, data);
+			return data;
+		}
+
+		public void DrawLinkDestinationAnnotation (SKRect rect, SKData value)
+		{
+			SkiaApi.sk_canvas_draw_link_destination_annotation (Handle, ref rect, value == null ? IntPtr.Zero : value.Handle);
+		}
+
+		public SKData DrawLinkDestinationAnnotation (SKRect rect, string value)
+		{
+			var data = SKData.FromCString (value);
+			DrawLinkDestinationAnnotation (rect, data);
+			return data;
+		}
+
 		public void DrawBitmapNinePatch (SKBitmap bitmap, SKRectI center, SKRect dst, SKPaint paint = null)
 		{
 			if (bitmap == null)

binding/Binding/SKData.cs

@@ -10,6 +10,7 @@
 using System;
 using System.Runtime.InteropServices;
 using System.IO;
+using System.Text;
 
 namespace SkiaSharp
 {
@@ -52,7 +53,12 @@ namespace SkiaSharp
 		}
 
 		public SKData (byte[] bytes)
-			: this (SkiaApi.sk_data_new_with_copy (bytes, (IntPtr) bytes.Length), true)
+			: this (bytes, (ulong) bytes.Length)
+		{
+		}
+
+		public SKData (byte[] bytes, ulong length)
+			: this (SkiaApi.sk_data_new_with_copy (bytes, (IntPtr) length), true)
 		{
 			if (Handle == IntPtr.Zero) {
 				throw new InvalidOperationException ("Unable to copy the SKData instance.");
@@ -66,6 +72,12 @@ namespace SkiaSharp
 			return GetObject<SKData> (SkiaApi.sk_data_new_from_malloc (bytes, (IntPtr) length));
 		}
 
+		internal static SKData FromCString (string str)
+		{
+			var bytes = Encoding.ASCII.GetBytes (str ?? string.Empty);
+			return new SKData (bytes, (ulong)(bytes.Length + 1)); // + 1 for the terminating char
+		}
+
 		public SKData Subset (ulong offset, ulong length)
 		{
 			if (Marshal.SizeOf (typeof(IntPtr)) == 4) {

binding/Binding/SkiaApi.cs

@@ -202,6 +202,15 @@ namespace SkiaSharp
 		[DllImport(SKIA, CallingConvention = CallingConvention.Cdecl)]
 		public extern static void sk_canvas_get_total_matrix(sk_canvas_t canvas, ref SKMatrix matrix);
 
+		[DllImport(SKIA, CallingConvention = CallingConvention.Cdecl)]
+		public extern static void sk_canvas_draw_annotation(sk_canvas_t t, ref SKRect rect, byte[] key, sk_data_t value);
+		[DllImport(SKIA, CallingConvention = CallingConvention.Cdecl)]
+		public extern static void sk_canvas_draw_url_annotation(sk_canvas_t t, ref SKRect rect, sk_data_t value);
+		[DllImport(SKIA, CallingConvention = CallingConvention.Cdecl)]
+		public extern static void sk_canvas_draw_named_destination_annotation(sk_canvas_t t, ref SKPoint point, sk_data_t value);
+		[DllImport(SKIA, CallingConvention = CallingConvention.Cdecl)]
+		public extern static void sk_canvas_draw_link_destination_annotation(sk_canvas_t t, ref SKRect rect, sk_data_t value);
+
 		[DllImport(SKIA, CallingConvention = CallingConvention.Cdecl)]
 		public extern static void sk_canvas_clip_rect_with_operation(sk_canvas_t t, ref SKRect crect, SKClipOperation op, bool doAA);
 		[DllImport(SKIA, CallingConvention = CallingConvention.Cdecl)]

externals/skia

@@ -1 +1 @@
-Subproject commit 706b362df172f4c2538e9f6848f9957a4ea9dc87
+Subproject commit a100ca604629d377d0ba1acbb3c41001561483fe