@@ -42,10 +42,25 @@ class TestDotWidget(DotWidget):

             import cairo

+            # Scale to give 96 dpi instead of 72 dpi

             dpi = 96.0

-            zoom_ratio = dpi/72.0

-            w = int(self.graph.width*zoom_ratio)

-            h = int(self.graph.height*zoom_ratio)

+            scale = dpi/72.0

+            w = int(self.graph.width*scale)

+            h = int(self.graph.height*scale)

+

+            CAIRO_XMAX = 32767

+            CAIRO_YMAX = 32767

+            if w >= CAIRO_XMAX:

+                w = CAIRO_XMAX

+                scale = w/self.graph.width

+                h = int(self.graph.height*scale)

+            if h >= CAIRO_YMAX:

+                h = CAIRO_YMAX

+                scale = h/self.graph.height

+                w = int(self.graph.width*scale)

+

+            assert w <= CAIRO_XMAX

+            assert h <= CAIRO_YMAX

             surface = cairo.ImageSurface(cairo.FORMAT_ARGB32, w, h)

@@ -54,7 +69,7 @@ class TestDotWidget(DotWidget):

             cr.set_source_rgba(1.0, 1.0, 1.0, 1.0)

             cr.paint()

-            cr.scale(zoom_ratio, zoom_ratio)

+            cr.scale(scale, scale)

             self.graph.draw(cr, highlight_items=self.highlight)

@@ -89,9 +104,12 @@ def main():

         except:

             exc_info = sys.exc_info()

             traceback.print_exception(*exc_info)

-        window.show()

-        Gtk.main()

-        window.destroy()

+            continue

+        try:

+            window.show()

+            Gtk.main()

+        finally:

+            window.destroy()

 if __name__ == '__main__':