From: Søren Sandmann Pedersen <ssp@redhat.com>
Date: Mon, 30 Aug 2010 02:46:09 +0000 (-0400)
Subject: Clip composite region against the destination alpha map extents.
X-Git-Tag: 1.0_branch~488
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=add0fd1bac84a5b6dddf7632b4100d6b3f2ebc18;p=profile%2Fivi%2Fpixman.git

Clip composite region against the destination alpha map extents.

Otherwise we can end up writing outside the alpha map.
---

diff --git a/pixman/pixman.c b/pixman/pixman.c
index cdf4b75..285bbfc 100644
--- a/pixman/pixman.c
+++ b/pixman/pixman.c
@@ -315,14 +315,27 @@ pixman_compute_composite_region32 (pixman_region32_t * region,
 	    return FALSE;
     }
 
-    if (dst_image->common.alpha_map && dst_image->common.alpha_map->common.have_clip_region)
+    if (dst_image->common.alpha_map)
     {
-	if (!clip_general_image (region, &dst_image->common.alpha_map->common.clip_region,
-	                         -dst_image->common.alpha_origin_x,
-	                         -dst_image->common.alpha_origin_y))
+	if (!pixman_region32_intersect_rect (region, region,
+					     dst_image->common.alpha_origin_x,
+					     dst_image->common.alpha_origin_y,
+					     dst_image->common.alpha_map->width,
+					     dst_image->common.alpha_map->height))
 	{
 	    return FALSE;
 	}
+	if (!pixman_region32_not_empty (region))
+	    return FALSE;
+	if (dst_image->common.alpha_map->common.have_clip_region)
+	{
+	    if (!clip_general_image (region, &dst_image->common.alpha_map->common.clip_region,
+				     -dst_image->common.alpha_origin_x,
+				     -dst_image->common.alpha_origin_y))
+	    {
+		return FALSE;
+	    }
+	}
     }
 
     /* clip against src */