diff --git a/test/mask.c b/test/mask.c
index a9414e046..6d0e45878 100644
--- a/test/mask.c
+++ b/test/mask.c
@@ -213,12 +213,10 @@ draw (cairo_t *cr, int width, int height)
 		int x = i * (WIDTH + PAD) + PAD;
 		int y = (ARRAY_SIZE (mask_funcs) * k + j) * (HEIGHT + PAD) + PAD;
 		
-		/* Clear area we are going to be drawing onto */
+		/* Clear intermediate surface we are going to be drawing onto */
 		cairo_save (cr2);
-		cairo_set_source_rgba (cr2, 0, 0, 0, 0); /* transparent */
-		cairo_set_operator (cr2, CAIRO_OPERATOR_SOURCE);
-		cairo_rectangle (cr2, x, y, WIDTH, HEIGHT);
-		cairo_fill (cr2);
+		cairo_set_operator (cr2, CAIRO_OPERATOR_CLEAR);
+		cairo_paint (cr2);
 		cairo_restore (cr2);
 
 		/* draw */