Go back to rect blur profile textures.
It's faster than analytic.
This version of profile texture has better binning and simpler shader
logic than the original. I believe it also avoids some integralization
that led to artifacts in the previous texture implementation.
We oversize the profile for the blur, bin by pow 2 with a 32 texel min
and then rescale the texture coordinates over a 6 sigma range in the
shader. We pre-inset the rect uniform so the texture is always placed
with one end at the rect edge, extending outward.
Bug: chromium:995308
Change-Id: I739db98d4df69de0f5b2f5dda079cf034ba32035
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/239119
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
3 files changed