add more conservative check for wayward divide

add more conservative check for wayward divide

When the parallel stroke to the curve can't be computed from
the intersection of the tangent lines, as straight line connects
the two points instead. Allow the intersection to succeed unless
the ratio isn't finite or the contribution of (1 - ratio) isn't
significant.

R=reed@google.com,fmalita@chromium.org
BUG=skia:4603
Committed: https://skia.googlesource.com/skia/+/b775e91e8760200f145a95672c29cc703b8a4f5f

[caryclark, 2015-11-30 20:37:18]

The CQ bit was checked by caryclark@google.com to run a CQ dry run

[commit-bot: I haz the power, 2015-11-30 20:37:26]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1484873003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1484873003/1

[commit-bot: I haz the power, 2015-11-30 20:56:37]

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

[commit-bot: I haz the power, 2015-11-30 20:56:38]

Dry run: This issue passed the CQ dry run.

[caryclark, 2015-11-30 21:09:16]

The CQ bit was checked by caryclark@google.com

[commit-bot: I haz the power, 2015-11-30 21:09:20]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1484873003/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1484873003/20001

[commit-bot: I haz the power, 2015-11-30 21:09:21]

Note for Reviewers:
The CQ is waiting for an approval.
If you believe that the CL is not ready yet, or if you would like to L-G-T-M
with comments then please uncheck the CQ checkbox.

Waiting for LGTM from valid reviewer(s) till 2015-12-01 03:09 UTC

[reed1, 2015-11-30 21:24:13]

lgtm

https://codereview.chromium.org/1484873003/diff/20001/src/core/SkStroke.cpp
File src/core/SkStroke.cpp (right):

https://codereview.chromium.org/1484873003/diff/20001/src/core/SkStroke.cpp#n...
src/core/SkStroke.cpp:842: bool validDivide = SkScalarIsFinite(numerA) && numerA
!= numerA - 1;
nit: is "numerA > (numerA - 1)" clearer?
I certainly had to read the comment to understand what this 2nd test was for.
not sure.

[reed1, 2015-11-30 21:24:18]

The CQ bit was unchecked by reed@google.com

[caryclark, 2015-11-30 21:25:12]

Description was changed from

==========
add more conservative check for wayward divide

When the parallel stroke to the curve can't be computed from
the intersection of the tangent lines, as straight line connects
the two points instead. Allow the intersection to succeed unless
the ratio isn't finite or the contribution of (1 - ratio) isn't
significant.

R=reed@google.com,fmalita@google.com
BUG=skia:4603
==========

to

==========
add more conservative check for wayward divide

When the parallel stroke to the curve can't be computed from
the intersection of the tangent lines, as straight line connects
the two points instead. Allow the intersection to succeed unless
the ratio isn't finite or the contribution of (1 - ratio) isn't
significant.

R=reed@google.com,fmalita@chromium.org
BUG=skia:4603
==========

[caryclark, 2015-11-30 21:25:12]

caryclark@google.com changed reviewers:
+ fmalita@chromium.org
- fmalita@google.com

[caryclark, 2015-11-30 21:29:54]

The CQ bit was checked by caryclark@google.com

[caryclark, 2015-11-30 21:29:54]

The patchset sent to the CQ was uploaded after l-g-t-m from reed@google.com
Link to the patchset: https://codereview.chromium.org/1484873003/#ps40001
(title: "greater than compare removes need for finite check")

[commit-bot: I haz the power, 2015-11-30 21:29:59]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1484873003/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1484873003/40001

[commit-bot: I haz the power, 2015-11-30 21:47:16]

Description was changed from

==========
add more conservative check for wayward divide

When the parallel stroke to the curve can't be computed from
the intersection of the tangent lines, as straight line connects
the two points instead. Allow the intersection to succeed unless
the ratio isn't finite or the contribution of (1 - ratio) isn't
significant.

R=reed@google.com,fmalita@chromium.org
BUG=skia:4603
==========

to

==========
add more conservative check for wayward divide

When the parallel stroke to the curve can't be computed from
the intersection of the tangent lines, as straight line connects
the two points instead. Allow the intersection to succeed unless
the ratio isn't finite or the contribution of (1 - ratio) isn't
significant.

R=reed@google.com,fmalita@chromium.org
BUG=skia:4603

Committed:
https://skia.googlesource.com/skia/+/b775e91e8760200f145a95672c29cc703b8a4f5f
==========

[commit-bot: I haz the power, 2015-11-30 21:47:16]

Committed patchset #3 (id:40001) as
https://skia.googlesource.com/skia/+/b775e91e8760200f145a95672c29cc703b8a4f5f