commit 74bdde0d50f45c5848381ec207c1464b70a48ee3
author senorblanco@chromium.org <senorblanco@chromium.org@2bbb7eff-a529-9590-31e7-b0007b416f81> Tue Jan 28 17:57:26 2014 +0000
committer senorblanco@chromium.org <senorblanco@chromium.org@2bbb7eff-a529-9590-31e7-b0007b416f81> Tue Jan 28 17:57:26 2014 +0000
tree 40f2e541bc8a38385c70d95d3e2691f004c243c5
parent c1587f94a77eaafe257a6ecf504364d40362c66a

Clamp negative sigma to 0 in SkDropShadowImageFilter.

This can occur when the matrix includes a perspective transform.

BUG=skia:2094
R=bsalomon@google.com

Review URL: https://codereview.chromium.org/137833004

git-svn-id: http://skia.googlecode.com/svn/trunk@13220 2bbb7eff-a529-9590-31e7-b0007b416f81

src/effects/SkDropShadowImageFilter.cpp

diff --git a/src/effects/SkDropShadowImageFilter.cpp b/src/effects/SkDropShadowImageFilter.cpp
index 4bb42a3..be99c67 100644
--- a/src/effects/SkDropShadowImageFilter.cpp
+++ b/src/effects/SkDropShadowImageFilter.cpp
@@ -79,6 +79,8 @@
 
     SkVector sigma, localSigma = SkVector::Make(fSigmaX, fSigmaY);
     matrix.mapVectors(&sigma, &localSigma, 1);
+    sigma.fX = SkMaxScalar(0, sigma.fX);
+    sigma.fY = SkMaxScalar(0, sigma.fY);
     SkAutoTUnref<SkImageFilter> blurFilter(new SkBlurImageFilter(sigma.fX, sigma.fY));
     SkAutoTUnref<SkColorFilter> colorFilter(SkColorFilter::CreateModeFilter(fColor, SkXfermode::kSrcIn_Mode));
     SkPaint paint;