Ref count vector image data objectscorrado/ref-count-vector-data

5 files changed, 68 insertions, 19 deletions

diff --git a/Xwt.Gtk/Xwt.GtkBackend/ImagePatternBackendHandler.cs b/Xwt.Gtk/Xwt.GtkBackend/ImagePatternBackendHandler.cs
index e77b857b..40f03849 100644
--- a/Xwt.Gtk/Xwt.GtkBackend/ImagePatternBackendHandler.cs
+++ b/Xwt.Gtk/Xwt.GtkBackend/ImagePatternBackendHandler.cs
@@ -51,7 +51,7 @@ namespace Xwt.GtkBackend
 		#endregion
 	}
 
-	class ImagePatternBackend
+	class ImagePatternBackend : IDisposable
 	{
 		public ImageDescription Image;
 
@@ -84,8 +84,10 @@ namespace Xwt.GtkBackend
 
 		public void Dispose ()
 		{
-			if (pattern != null)
+			if (pattern != null) {
 				pattern.Dispose ();
+				pattern = null;
+			}
 		}
 	}
 }
diff --git a/Xwt/Xwt.Backends/ResourceManager.cs b/Xwt/Xwt.Backends/ResourceManager.cs
index f954b374..b3b90818 100644
--- a/Xwt/Xwt.Backends/ResourceManager.cs
+++ b/Xwt/Xwt.Backends/ResourceManager.cs
@@ -30,16 +30,33 @@ namespace Xwt.Backends
 {
 	static class ResourceManager
 	{
+		class Ref {
+			public int RefCount;
+			public Action<object> Disposer;
+
+			public Ref (Action<object> disposer)
+			{
+				RefCount = 1;
+				Disposer = disposer;
+			}
+		}
+
 		static bool finalized;
-		static Dictionary<object,Action<object>> resources = new Dictionary<object,Action<object>> ();
+		static Dictionary<object,Ref> resources = new Dictionary<object,Ref> ();
 		static Dictionary<object,Action<object>> freedResources = new Dictionary<object,Action<object>> ();
 
 		public static void RegisterResource (object res, Action<object> disposeCallback = null)
 		{
 			if (finalized)
 				return;
-			lock (resources)
-				resources [res] = disposeCallback;
+
+			Ref reference;
+			lock (resources) {
+				if (resources.TryGetValue (res, out reference))
+					reference.RefCount++;
+				else
+					resources.Add (res, new Ref (disposeCallback));
+			}
 		}
 
 		public static bool FreeResource (object res)
@@ -48,19 +65,19 @@ namespace Xwt.Backends
 				return true;
 
 			lock (resources) {
-				Action<object> disposer;
-				if (!resources.TryGetValue (res, out disposer))
+				Ref reference;
+				if (!resources.TryGetValue (res, out reference) || --reference.RefCount > 0)
 					return false;
 
 				resources.Remove (res);
 
 				if (System.Threading.Thread.CurrentThread == Application.UIThread) {
-					DisposeResource (res, disposer);
+					DisposeResource (res, reference.Disposer);
 				} else {
 					lock (freedResources) {
 						if (freedResources.Count == 0)
 							Application.Invoke (DisposeResources);
-						freedResources [res] = disposer;
+						freedResources [res] = reference.Disposer;
 					}
 				}
 				return true;
diff --git a/Xwt/Xwt.Drawing/Image.cs b/Xwt/Xwt.Drawing/Image.cs
index 240aa497..81513515 100644
--- a/Xwt/Xwt.Drawing/Image.cs
+++ b/Xwt/Xwt.Drawing/Image.cs
@@ -87,8 +87,10 @@ namespace Xwt.Drawing
 
 		protected virtual void Dispose (bool disposing)
 		{
-			if (NativeRef != null)
+			if (NativeRef != null) {
 				NativeRef.ReleaseReference (disposing);
+				NativeRef = null;
+			}
 		}
 
 
diff --git a/Xwt/Xwt.Drawing/ImageBuilder.cs b/Xwt/Xwt.Drawing/ImageBuilder.cs
index 172677fe..0728bb9d 100644
--- a/Xwt/Xwt.Drawing/ImageBuilder.cs
+++ b/Xwt/Xwt.Drawing/ImageBuilder.cs
@@ -73,27 +73,32 @@ namespace Xwt.Drawing
 
 		public BitmapImage ToBitmap (ImageFormat format = ImageFormat.ARGB32)
 		{
-			return ToVectorImage ().ToBitmap (format);
+			using (var vector = ToVectorImage ())
+				return vector.ToBitmap (format);
 		}
 
 		public BitmapImage ToBitmap (Widget renderTarget, ImageFormat format = ImageFormat.ARGB32)
 		{
-			return ToVectorImage ().ToBitmap (renderTarget, format);
+			using (var vector = ToVectorImage ())
+				return vector.ToBitmap (renderTarget, format);
 		}
 
 		public BitmapImage ToBitmap (Window renderTarget, ImageFormat format = ImageFormat.ARGB32)
 		{
-			return ToVectorImage ().ToBitmap (renderTarget, format);
+			using (var vector = ToVectorImage ())
+				return vector.ToBitmap (renderTarget, format);
 		}
 
 		public BitmapImage ToBitmap (Screen renderTarget, ImageFormat format = ImageFormat.ARGB32)
 		{
-			return ToVectorImage ().ToBitmap (renderTarget, format);
+			using (var vector = ToVectorImage ())
+				return vector.ToBitmap (renderTarget, format);
 		}
 
 		public BitmapImage ToBitmap (double scaleFactor, ImageFormat format = ImageFormat.ARGB32)
 		{
-			return ToVectorImage ().ToBitmap (scaleFactor, format);
+			using (var vector = ToVectorImage ())
+				return vector.ToBitmap (scaleFactor, format);
 		}
 	}
 }
diff --git a/Xwt/Xwt.Drawing/VectorImage.cs b/Xwt/Xwt.Drawing/VectorImage.cs
index 0644ca69..eaa53c44 100644
--- a/Xwt/Xwt.Drawing/VectorImage.cs
+++ b/Xwt/Xwt.Drawing/VectorImage.cs
@@ -48,9 +48,15 @@ namespace Xwt.Drawing
 			ToolkitEngine.VectorImageRecorderContextHandler.Draw (ctx.Handler, Toolkit.GetBackend (ctx), data);
 			ctx.Restore ();
 		}
+
+		protected override void Dispose (bool disposing)
+		{
+			base.Dispose (disposing);
+			data.Dispose ();
+		}
 	}
 
-	class VectorImageData
+	class VectorImageData : IDisposable
 	{
 		public DrawingCommand[] Commands;
 		public double[] Doubles;
@@ -60,6 +66,12 @@ namespace Xwt.Drawing
 		public object[] Objects;
 		public ImageDescription[] Images;
 		public TextLayoutData[] TextLayouts;
+
+		public void Dispose ()
+		{
+			foreach (var obj in Objects)
+				ResourceManager.FreeResource (obj);
+		}
 	}
 
 	enum DrawingCommand
@@ -204,22 +216,32 @@ namespace Xwt.Drawing
 
 		public VectorImageData ToVectorImageData ()
 		{
-			return new VectorImageData () {
+			var data = new VectorImageData () {
 				Commands = Commands.ToArray (),
 				Doubles = Doubles.ToArray (),
 				Colors = Colors.ToArray (),
 				Images = Images.ToArray (),
 				Ints = Ints.ToArray (),
 				Rectangles = Rectangles.ToArray (),
-				Objects = Objects.ToArray (),
 				TextLayouts = TextLayouts.ToArray (),
 			};
+			data.Objects = new object [Objects.Count];
+			for (var i = 0; i < Objects.Count; i++) {
+				var obj = Objects [i];
+				data.Objects [i] = obj;
+				ResourceManager.RegisterResource (obj);
+			}
+			return data;
 		}
 
 		public virtual void Dispose ()
 		{
-			if (NativeBackend != null)
+			if (NativeBackend != null) {
 				NativePathHandler.Dispose (NativeBackend);
+				NativeBackend = null;
+			}
+			foreach (var obj in Objects)
+				ResourceManager.FreeResource (obj);
 		}
 	}
 
@@ -486,6 +508,7 @@ namespace Xwt.Drawing
 			var ctx = (VectorBackend)backend;
 			ctx.Commands.Add (DrawingCommand.SetPattern);
 			ctx.Objects.Add (p);
+			ResourceManager.RegisterResource (p);
 		}
 
 		public override void DrawTextLayout (object backend, TextLayout layout, double x, double y)