reftests: Make diff pixels always opaque

We had pixels that did not differ in alpha and we then set 0 alpha
difference hich made the pixel invisible. Oops.

diff --git a/testsuite/reftests/reftest-compare.c b/testsuite/reftests/reftest-compare.c
index 5bccb697b8aaefd7efdc04555d69f55fb4dc1a25..a24ab337a6744a91c2afa9c459b14fd93e8c5cb6 100644 (file)
--- a/testsuite/reftests/reftest-compare.c
+++ b/testsuite/reftests/reftest-compare.c
@@ -143,6 +143,8 @@ buffer_diff_core (const guchar *buf_a,
               guint8 alpha = diff_pixel >> 24;
               diff_pixel = alpha * 0x010101;
             }
+          /* make the pixel fully opaque */
+          diff_pixel |= 0xff000000;
           
           row[x] = diff_pixel;
       }