cairo version of sprite library

1 files changed, 15 insertions, 1 deletions

diff --git a/abacus_window.py b/abacus_window.py
index 9be9b89..b340a8f 100644
--- a/abacus_window.py
+++ b/abacus_window.py
@@ -857,9 +857,23 @@ class Abacus():
 
     def _expose_cb(self, win, event):
         ''' Callback to handle window expose events '''
-        self.sprites.redraw_sprites(event.area)
+        self.do_expose_event(event)
         return True
 
+    # Handle the expose-event by drawing
+    def do_expose_event(self, event):
+
+        # Create the cairo context
+        cr = self.canvas.window.cairo_create()
+
+        # Restrict Cairo to the exposed area; avoid extra work
+        cr.rectangle(event.area.x, event.area.y,
+                event.area.width, event.area.height)
+        cr.clip()
+
+        # Refresh sprite list
+        self.sprites.redraw_sprites(cr=cr)
+
     def _destroy_cb(self, win, event):
         ''' Callback to handle quit '''
         gtk.main_quit()