[Reland] Repeating SkBitmapProcState rounding bias

[Reland] Repeating SkBitmapProcState rounding bias

1) observe the bias in repeat matrix procs also.
2) add utility for device space -> bitmap space mapping.
3) remove unneeded filter bias

This is a reland of https://codereview.chromium.org/1529833003/. The
main difference (and the fix) vs. the prev version is increased
precision: the mapper now operates with SkFractionalInts.

R=reed@google.com
BUG=skia:4680, skia:4649
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1539083002

Committed: https://skia.googlesource.com/skia/+/b3a835891cf221bdf4c6eeb4cf404b374955015f

[f(malita), 2015-12-19 17:54:45]

Description was changed from

==========
[Reland] Repeating SkBitmapProcState rounding bias

1) observe the bias in repeat matrix procs also.
2) add utility for device space -> bitmap space mapping.
3) remove unneeded filter bias

This is a reland of https://codereview.chromium.org/1529833003/. The
main difference (and the fix) vs. the prev version is increased
precision: the mapper now operates with SkFractionalInts.

BUG=skia:4680, skia:4649
==========

to

==========
[Reland] Repeating SkBitmapProcState rounding bias

1) observe the bias in repeat matrix procs also.
2) add utility for device space -> bitmap space mapping.
3) remove unneeded filter bias

This is a reland of https://codereview.chromium.org/1529833003/. The
main difference (and the fix) vs. the prev version is increased
precision: the mapper now operates with SkFractionalInts.

BUG=skia:4680, skia:4649
GOLD_TRYBOT_URL=
https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&is...
==========

[f(malita), 2015-12-19 17:57:50]

Description was changed from

==========
[Reland] Repeating SkBitmapProcState rounding bias

1) observe the bias in repeat matrix procs also.
2) add utility for device space -> bitmap space mapping.
3) remove unneeded filter bias

This is a reland of https://codereview.chromium.org/1529833003/. The
main difference (and the fix) vs. the prev version is increased
precision: the mapper now operates with SkFractionalInts.

BUG=skia:4680, skia:4649
GOLD_TRYBOT_URL=
https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&is...
==========

to

==========
[Reland] Repeating SkBitmapProcState rounding bias

1) observe the bias in repeat matrix procs also.
2) add utility for device space -> bitmap space mapping.
3) remove unneeded filter bias

This is a reland of https://codereview.chromium.org/1529833003/. The
main difference (and the fix) vs. the prev version is increased
precision: the mapper now operates with SkFractionalInts.

R=reed@google.com
BUG=skia:4680, skia:4649
GOLD_TRYBOT_URL=
https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&is...
==========

[f(malita), 2015-12-19 17:57:50]

fmalita@chromium.org changed reviewers:
+ reed@google.com

[f(malita), 2015-12-19 17:57:58]

PTAL

[f(malita), 2015-12-19 17:58:13]

The CQ bit was checked by fmalita@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2015-12-19 17:58:21]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1539083002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1539083002/20001

[commit-bot: I haz the power, 2015-12-19 18:13:48]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-12-19 18:13:49]

Dry run: This issue passed the CQ dry run.

[f(malita), 2015-12-21 16:16:07]

On 2015/12/19 18:13:49, commit-bot: I haz the power wrote:
> Dry run: This issue passed the CQ dry run.

PTAL

[f(malita), 2016-01-04 15:30:45]

On 2015/12/21 16:16:07, f(malita) wrote:
> On 2015/12/19 18:13:49, commit-bot: I haz the power wrote:
> > Dry run: This issue passed the CQ dry run.
> 
> PTAL

Bump.

[reed1, 2016-01-04 17:55:57]

https://codereview.chromium.org/1539083002/diff/20001/src/core/SkBitmapProcSt...
File src/core/SkBitmapProcState.h (right):

https://codereview.chromium.org/1539083002/diff/20001/src/core/SkBitmapProcSt...
src/core/SkBitmapProcState.h:219: fX = SkScalarToFractionalInt(pt.x()) -
SkFixedToFractionalInt(s.fInvMatrix.getScaleX() > 0);
Now that is a tricky expression: SkFixedToFractionalInt(s.fInvMatrix.getScaleX()
> 0)

I presume its the same as:

bias = 0;
if (s.fInvMatrix.getScaleX() > 0) {
    bias = 1 << 16;
}

[reed1, 2016-01-04 17:56:02]

lgtm

[f(malita), 2016-01-04 18:04:27]

https://codereview.chromium.org/1539083002/diff/20001/src/core/SkBitmapProcSt...
File src/core/SkBitmapProcState.h (right):

https://codereview.chromium.org/1539083002/diff/20001/src/core/SkBitmapProcSt...
src/core/SkBitmapProcState.h:219: fX = SkScalarToFractionalInt(pt.x()) -
SkFixedToFractionalInt(s.fInvMatrix.getScaleX() > 0);
On 2016/01/04 17:55:57, reed1 wrote:
> Now that is a tricky expression:
SkFixedToFractionalInt(s.fInvMatrix.getScaleX()
> > 0)
> 
> I presume its the same as:
> 
> bias = 0;
> if (s.fInvMatrix.getScaleX() > 0) {
>     bias = 1 << 16;
> }

Right.  Maybe something like this would look more straightforward?

SkFixed biasX = (s.fInvMatrix.getScaleX() > 0);
fX = SkScalarToFractionalInt(pt.x()) - SkFixedToFractionalInt(biasX);

[f(malita), 2016-01-04 18:09:15]

On 2016/01/04 18:04:27, f(malita) wrote:
>
https://codereview.chromium.org/1539083002/diff/20001/src/core/SkBitmapProcSt...
> File src/core/SkBitmapProcState.h (right):
> 
>
https://codereview.chromium.org/1539083002/diff/20001/src/core/SkBitmapProcSt...
> src/core/SkBitmapProcState.h:219: fX = SkScalarToFractionalInt(pt.x()) -
> SkFixedToFractionalInt(s.fInvMatrix.getScaleX() > 0);
> On 2016/01/04 17:55:57, reed1 wrote:
> > Now that is a tricky expression:
> SkFixedToFractionalInt(s.fInvMatrix.getScaleX()
> > > 0)
> > 
> > I presume its the same as:
> > 
> > bias = 0;
> > if (s.fInvMatrix.getScaleX() > 0) {
> >     bias = 1 << 16;
> > }
> 
> Right.  Maybe something like this would look more straightforward?
> 
> SkFixed biasX = (s.fInvMatrix.getScaleX() > 0);
> fX = SkScalarToFractionalInt(pt.x()) - SkFixedToFractionalInt(biasX);

(i'll land as-is to get the Blink deps going, we can talk & tweak the expression
later)

[f(malita), 2016-01-04 18:09:24]

The CQ bit was checked by fmalita@chromium.org

[commit-bot: I haz the power, 2016-01-04 18:09:30]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1539083002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1539083002/20001

[commit-bot: I haz the power, 2016-01-04 18:28:13]

Description was changed from

==========
[Reland] Repeating SkBitmapProcState rounding bias

1) observe the bias in repeat matrix procs also.
2) add utility for device space -> bitmap space mapping.
3) remove unneeded filter bias

This is a reland of https://codereview.chromium.org/1529833003/. The
main difference (and the fix) vs. the prev version is increased
precision: the mapper now operates with SkFractionalInts.

R=reed@google.com
BUG=skia:4680, skia:4649
GOLD_TRYBOT_URL=
https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&is...
==========

to

==========
[Reland] Repeating SkBitmapProcState rounding bias

1) observe the bias in repeat matrix procs also.
2) add utility for device space -> bitmap space mapping.
3) remove unneeded filter bias

This is a reland of https://codereview.chromium.org/1529833003/. The
main difference (and the fix) vs. the prev version is increased
precision: the mapper now operates with SkFractionalInts.

R=reed@google.com
BUG=skia:4680, skia:4649
GOLD_TRYBOT_URL=
https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&is...

Committed:
https://skia.googlesource.com/skia/+/b3a835891cf221bdf4c6eeb4cf404b374955015f
==========

[commit-bot: I haz the power, 2016-01-04 18:28:13]

Committed patchset #2 (id:20001) as
https://skia.googlesource.com/skia/+/b3a835891cf221bdf4c6eeb4cf404b374955015f