Use Analytic AA in SkAAClip

Use Analytic AA in SkAAClip.

This will fix some Chrome ref tests.

The main issue here is that the SkAAClip requires: (1) we blit in order, and (2) we must forceRLE.

Note that this still depends on the global gSkUseAnalyticAA to turn on the Analytic AA.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2430343003

Committed: https://skia.googlesource.com/skia/+/2add0ffdaab4c33ca6702c81533c88c7b5ca7294

[liyuqian, 2016-10-19 17:08:59]

Description was changed from

==========
Use Analytic AA in SkAAClip

BUG=skia:
==========

to

==========
Use Analytic AA in SkAAClip

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2430343003
==========

[liyuqian, 2016-10-20 15:29:08]

Description was changed from

==========
Use Analytic AA in SkAAClip

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2430343003
==========

to

==========
Use Analytic AA in SkAAClip.

Note that this still depends on the global gSkUseAnalyticAA to turn on the
Analytic AA.

I've also CC'ed those who expressed some interests in the Analytic AA and asked
me to CC them maybe back in the July. Please let me know if you no longer want
me to CC you about the future change.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2430343003
==========

[liyuqian, 2016-10-20 15:29:08]

liyuqian@google.com changed reviewers:
+ caryclark@google.com, reed@google.com

[liyuqian, 2016-10-20 15:29:32]

Description was changed from

==========
Use Analytic AA in SkAAClip.

Note that this still depends on the global gSkUseAnalyticAA to turn on the
Analytic AA.

I've also CC'ed those who expressed some interests in the Analytic AA and asked
me to CC them maybe back in the July. Please let me know if you no longer want
me to CC you about the future change.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2430343003
==========

to

==========
Use Analytic AA in SkAAClip.

Note that this still depends on the global gSkUseAnalyticAA to turn on the
Analytic AA.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2430343003
==========

[liyuqian, 2016-10-20 15:31:12]

Description was changed from

==========
Use Analytic AA in SkAAClip.

Note that this still depends on the global gSkUseAnalyticAA to turn on the
Analytic AA.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2430343003
==========

to

==========
Use Analytic AA in SkAAClip.

The main issue here is that the SkAAClip requires: (1) we blit in order, and (2)
we must forceRLE.

Note that this still depends on the global gSkUseAnalyticAA to turn on the
Analytic AA.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2430343003
==========

[liyuqian, 2016-10-20 15:31:25]

I've also CC'ed those who expressed some interests in the Analytic AA and asked
me to CC them maybe back in the July. Please let me know if you no longer want
me to CC you about the future change.

[liyuqian, 2016-10-20 15:32:05]

Description was changed from

==========
Use Analytic AA in SkAAClip.

The main issue here is that the SkAAClip requires: (1) we blit in order, and (2)
we must forceRLE.

Note that this still depends on the global gSkUseAnalyticAA to turn on the
Analytic AA.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2430343003
==========

to

==========
Use Analytic AA in SkAAClip.

This will fix some Chrome ref tests.

The main issue here is that the SkAAClip requires: (1) we blit in order, and (2)
we must forceRLE.

Note that this still depends on the global gSkUseAnalyticAA to turn on the
Analytic AA.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2430343003
==========

[caryclark, 2016-10-20 16:58:14]

lgtm (with nits)

https://codereview.chromium.org/2430343003/diff/60001/src/core/SkAAClip.cpp
File src/core/SkAAClip.cpp (right):

https://codereview.chromium.org/2430343003/diff/60001/src/core/SkAAClip.cpp#n...
src/core/SkAAClip.cpp:1044: 1 + (rightAlpha > 0 ? 1 : 0),
could this be

SkASSERT(fBounds.contains(x + width + (rightAlpha > 0), y + height - 1));

https://codereview.chromium.org/2430343003/diff/60001/src/core/SkAnalyticEdge.h
File src/core/SkAnalyticEdge.h (right):

https://codereview.chromium.org/2430343003/diff/60001/src/core/SkAnalyticEdge...
src/core/SkAnalyticEdge.h:46: return (y + (SK_Fixed1 >> (accuracy + 1))) >> (16
- accuracy) << (16 - accuracy);
As I overheard mtklein say, this looks like a job for SkLeftShift

https://codereview.chromium.org/2430343003/diff/60001/src/core/SkScan_AAAPath...
File src/core/SkScan_AAAPath.cpp (right):

https://codereview.chromium.org/2430343003/diff/60001/src/core/SkScan_AAAPath...
src/core/SkScan_AAAPath.cpp:284: if ((y >> 16) != (nextY >> 16)) {
maybe overly wordy, but a macro like SkFixedFloorToInt(y) instead of y >> 16
will help the reader know where the >> 16 comes from, here and below

[liyuqian, 2016-10-20 17:19:50]

Thanks for the comments! Nit fixed.

https://codereview.chromium.org/2430343003/diff/60001/src/core/SkAAClip.cpp
File src/core/SkAAClip.cpp (right):

https://codereview.chromium.org/2430343003/diff/60001/src/core/SkAAClip.cpp#n...
src/core/SkAAClip.cpp:1044: 1 + (rightAlpha > 0 ? 1 : 0),
On 2016/10/20 16:58:14, caryclark wrote:
> could this be
> 
> SkASSERT(fBounds.contains(x + width + (rightAlpha > 0), y + height - 1));

Sure, done. I was just preserving the old format for comparison.

https://codereview.chromium.org/2430343003/diff/60001/src/core/SkScan_AAAPath...
File src/core/SkScan_AAAPath.cpp (right):

https://codereview.chromium.org/2430343003/diff/60001/src/core/SkScan_AAAPath...
src/core/SkScan_AAAPath.cpp:284: if ((y >> 16) != (nextY >> 16)) {
On 2016/10/20 16:58:14, caryclark wrote:
> maybe overly wordy, but a macro like SkFixedFloorToInt(y) instead of y >> 16
> will help the reader know where the >> 16 comes from, here and below

Thanks, done.

[liyuqian, 2016-10-20 17:33:32]

The CQ bit was checked by liyuqian@google.com

[liyuqian, 2016-10-20 17:33:32]

The patchset sent to the CQ was uploaded after l-g-t-m from caryclark@google.com
Link to the patchset: https://codereview.chromium.org/2430343003/#ps80001
(title: "Nit fixes")

[commit-bot: I haz the power, 2016-10-20 17:33:43]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-10-20 18:04:41]

Description was changed from

==========
Use Analytic AA in SkAAClip.

This will fix some Chrome ref tests.

The main issue here is that the SkAAClip requires: (1) we blit in order, and (2)
we must forceRLE.

Note that this still depends on the global gSkUseAnalyticAA to turn on the
Analytic AA.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2430343003
==========

to

==========
Use Analytic AA in SkAAClip.

This will fix some Chrome ref tests.

The main issue here is that the SkAAClip requires: (1) we blit in order, and (2)
we must forceRLE.

Note that this still depends on the global gSkUseAnalyticAA to turn on the
Analytic AA.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2430343003

Committed:
https://skia.googlesource.com/skia/+/2add0ffdaab4c33ca6702c81533c88c7b5ca7294
==========

[commit-bot: I haz the power, 2016-10-20 18:04:43]

Committed patchset #5 (id:80001) as
https://skia.googlesource.com/skia/+/2add0ffdaab4c33ca6702c81533c88c7b5ca7294