tree b62a5274d4b1cbcaac89ad5fb8bf86118c7caa87
parent 981deec8b2928f07e3899849bed31bfbb8c19b9b
author wutao <wutao@google.com> 1498844685 -0700
committer Skia Commit-Bot <skia-commit-bot@chromium.org> 1498846276 +0000

Added new edge handling mode (clamp and repeat) to Gaussian blur filter.

Gaussian blur filter will interpolate value by using out of bounds
coords, which is 0. This makes it appears darker near the bounds in the
blurred images. There are two issues: 1) when downsampling and
upsampling, we should use GrTextureDomainEffect kClamp_Mode to clamp
the texture coords to the bounds; 2) during Gaussian blur, we need to
clamp to texture bounds.

BUG=622128
TEST=cc_unittests, GM image test & manual. Some test results can be found at:
https://bugs.chromium.org/p/chromium/issues/detail?id=622128#c49
Change-Id: I9283da1d91efb0da94a991f2d372e9f62c288bdc
Reviewed-on: https://skia-review.googlesource.com/20465
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Stephen White <senorblanco@chromium.org>
Reviewed-by: Robert Phillips <robertphillips@google.com>
Reviewed-by: Mike Reed <reed@google.com>