tree f31a4962f3ab6f998bdf740087e639257c542d61
parent ae325f50862ff99e37cb19baa37e5b62db441709
author Brian Salomon <bsalomon@google.com> 1667594273 -0400
committer SkCQ <skcq-be@skia-corp.google.com.iam.gserviceaccount.com> 1667931243 +0000

Make CPU nearest image sampling round down and remove matrix tweak

Manipulating the "total matrix" is incompatible with the
idea that effects might insert non-linear transformations of the
local coords.

Instead we modify the code that samples images to round down at
exact integers by subtracting one ULP before taking the floor. This makes drawing an image at 1:1 device to image pixels but with a half pixel skew continue to select each image pixel once. However -1:1 with
a half pixel skew will repeat one value and miss one value.

Put behind guard for now pending Chrome test rebaseline.

Bug: skia:13752
Change-Id: If86f6cf9821c0dd23bc7835d89a789d0d70e546a
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/585397
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>