commit 8b9a725823fb195f24a85b5004b988e42fa82ef8
author Yuqian Li <liyuqian@google.com> Fri Nov 11 09:40:34 2016 -0500
committer Skia Commit-Bot <skia-commit-bot@chromium.org> Fri Nov 11 16:15:08 2016 +0000
tree 1667320b1e70aa09470a42db89c65d463e08d724
parent c4f66af20e3a58a09554eb3db2bf45c6291fe3a8

Skip left/right if alpha = 0 in SkRectClipCheckBlitter::blitAntiRect

BUG=skia:

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=4684

Change-Id: I8c5e5f460dba76f9d74718f7ea104cb1f3cea993
Reviewed-on: https://skia-review.googlesource.com/4684
Commit-Queue: Yuqian Li <liyuqian@google.com>
Reviewed-by: Cary Clark <caryclark@google.com>

src/core/SkBlitter.cpp

diff --git a/src/core/SkBlitter.cpp b/src/core/SkBlitter.cpp
index e5c935b..b814325 100644
--- a/src/core/SkBlitter.cpp
+++ b/src/core/SkBlitter.cpp
@@ -1052,7 +1052,10 @@
 
 void SkRectClipCheckBlitter::blitAntiRect(int x, int y, int width, int height,
                                      SkAlpha leftAlpha, SkAlpha rightAlpha) {
-    SkASSERT(fClipRect.contains(SkIRect::MakeXYWH(x, y, width + 2, height)));
+    bool skipLeft = !leftAlpha;
+    bool skipRight = !rightAlpha;
+    SkASSERT(fClipRect.contains(SkIRect::MakeXYWH(x + skipLeft, y,
+            width + 2 - skipRight - skipLeft, height)));
     fBlitter->blitAntiRect(x, y, width, height, leftAlpha, rightAlpha);
 }