1 files changed, 59 insertions, 0 deletions
diff --git a/src/cached-image.vala b/src/cached-image.vala
new file mode 100644
index 0000000..56157a3
--- /dev/null
+++ b/src/cached-image.vala
@@ -0,0 +1,59 @@
+/* -*- Mode: Vala; indent-tabs-mode: nil; tab-width: 4 -*-
+ *
+ * Copyright (C) 2012 Canonical Ltd
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Michael Terry <michael.terry@canonical.com>
+ */
+
+public class CachedImage : Gtk.Image
+{
+    private static HashTable<Gdk.Pixbuf, Cairo.Surface> surface_table;
+
+    public static Cairo.Surface? get_cached_surface (Cairo.Context c, Gdk.Pixbuf pixbuf)
+    {
+        if (surface_table == null)
+            surface_table = new HashTable<Gdk.Pixbuf, Cairo.Surface> (direct_hash, direct_equal);
+
+        var surface = surface_table.lookup (pixbuf);
+        if (surface == null)
+        {
+            surface = new Cairo.Surface.similar (c.get_target (), Cairo.Content.COLOR_ALPHA, pixbuf.width, pixbuf.height);
+            var new_c = new Cairo.Context (surface);
+            Gdk.cairo_set_source_pixbuf (new_c, pixbuf, 0, 0);
+            new_c.paint ();
+            surface_table.insert (pixbuf, surface);
+        }
+        return surface;
+    }
+
+    public CachedImage (Gdk.Pixbuf? pixbuf)
+    {
+        Object (pixbuf: pixbuf);
+    }
+
+    public override bool draw (Cairo.Context c)
+    {
+        if (pixbuf != null)
+        {
+            var cached_surface = get_cached_surface (c, pixbuf);
+            if (cached_surface != null)
+            {
+                c.set_source_surface (cached_surface, 0, 0);
+                c.paint ();
+            }
+        }
+        return false;
+    }
+}