tree ddc5eddf771019decfe6a3401ea9b2da79dbc68a
parent e36f3baa78cbf4a7bab6e5f14702d6a4d259abde
author bsalomon@google.com <bsalomon@google.com@2bbb7eff-a529-9590-31e7-b0007b416f81> 1364584956 +0000
committer bsalomon@google.com <bsalomon@google.com@2bbb7eff-a529-9590-31e7-b0007b416f81> 1364584956 +0000

Add support for reading the dst pixel value in an effect. Use in a new effect for the kDarken xfer mode.

The current implementation is to always make a copy of the entire dst before the draw.
It will only succeed if the RT is also a texture.
Obviously, there is lots of room for improvement.
Review URL: https://codereview.chromium.org/13314002

git-svn-id: http://skia.googlecode.com/svn/trunk@8449 2bbb7eff-a529-9590-31e7-b0007b416f81