Reland "Use over-sampling to avoid branches in 2D blur effect"
This reverts commit 6ff22cb04a14e373fc9780bc955775fbe85b4ca0.
Reason for revert: updated Graphite's uniform setting
Original change's description:
> Revert "Use over-sampling to avoid branches in 2D blur effect"
>
> This reverts commit 4bc8ea0d75426f3fd3b3d6870159701ac3f3191d.
>
> Reason for revert: Need to update Graphite's TextureUtils to match updated 2D shader.
>
> Original change's description:
> > Use over-sampling to avoid branches in 2D blur effect
> >
> > It refactors the bucketing and static variables into a template
> > function. Now that both 1D and 2D are defined in terms of an already
> > calculated kernel size, the bucketing on multiples of 4 and 8 is the
> > same.
> >
> > Since the 2D effect packs 4 weights into a single half4, the 4-wise
> > bucketing fits fairly well. This reworks the effect to take another
> > half4 array of packed offsets that hold the 2D kernel offsets that
> > had been calculated based on the loop index and with branches.
> >
> > Given the apparent cost of branches on these GPUs, I think this space
> > tradeoff will probably be worth it. To compensate for this extra
> > complex uniform, a new utility function is calculated to fill out the
> > 2D array, carrying the last true offset to the over-sampled offsets
> > like I'd done in the 1D case previously
> >
> > Bug: b/297590025
> > Change-Id: I42ac74280772492915c65cbc40aca31516045cbb
> > Reviewed-on: https://skia-review.googlesource.com/c/skia/+/750343
> > Reviewed-by: Brian Osman <brianosman@google.com>
> > Commit-Queue: Michael Ludwig <michaelludwig@google.com>
>
> Bug: b/297590025
> Change-Id: I16212313a99184ebd8fb4f073f4c0c3e33d95193
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/754897
> Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
> Auto-Submit: Michael Ludwig <michaelludwig@google.com>
> Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bug: b/297590025
Change-Id: Ic5c252b9ee4fd3dea6d0f1e6bf3fb53fa878b044
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/755039
Reviewed-by: Brian Osman <brianosman@google.com>
Auto-Submit: Michael Ludwig <michaelludwig@google.com>
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
4 files changed
