[longomatch] Clip the drawing area in the Cairo context

[Andoni Morales Alastruey <amorales src gnome org>]

commit 45a22db9669478ec605efe4cc7eb89dcf4dc81d7
Author: Andoni Morales Alastruey <ylatuya gmail com>
Date:   Tue Sep 2 15:38:42 2014 +0200

    Clip the drawing area in the Cairo context

 LongoMatch.Drawing.Cairo/WidgetWrapper.cs |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)
---
diff --git a/LongoMatch.Drawing.Cairo/WidgetWrapper.cs b/LongoMatch.Drawing.Cairo/WidgetWrapper.cs
index 6b0838f..2b41a5f 100644
--- a/LongoMatch.Drawing.Cairo/WidgetWrapper.cs
+++ b/LongoMatch.Drawing.Cairo/WidgetWrapper.cs
@@ -204,9 +204,13 @@ namespace LongoMatch.Drawing.Cairo
                {
                        if (DrawEvent != null) {
                                using (CairoContext c = new CairoContext (widget.GdkWindow)) {
+                                       global::Cairo.Context cc = c.Value as global::Cairo.Context;
                                        if (area == null) {
-                                               area = new Area (new Point (0, 0), Width, Height);
+                                               Rectangle r = widget.GdkWindow.ClipRegion.Clipbox;
+                                               area = new Area (new Point (r.X, r.Y), r.Width, r.Height);
                                        }
+                                       cc.Rectangle (area.Start.X, area.Start.Y, area.Width, area.Height);
+                                       cc.Clip ();
                                        DrawEvent (c, area);
                                }
                        }