From add0fd1bac84a5b6dddf7632b4100d6b3f2ebc18 Mon Sep 17 00:00:00 2001 From: =?utf8?q?S=C3=B8ren=20Sandmann=20Pedersen?= Date: Sun, 29 Aug 2010 22:46:09 -0400 Subject: [PATCH] Clip composite region against the destination alpha map extents. Otherwise we can end up writing outside the alpha map. --- pixman/pixman.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) 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 */ -- 2.7.4