Fully check basis vectors for extent degeneracy.

Fully check basis vectors for extent degeneracy.

The test for 'nearly singular matrix' in SkScalerContext::computeMatrices
is actually a check to see if anything will draw. Unfortunately, the
current test only checks when the a skew causes nothing to draw. This
adds the check for when the scale causes nothing to draw.

BUG=skia:4998
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1735613002

Committed: https://skia.googlesource.com/skia/+/e37514d0b540a25471fe12ba6412dc4c8b9f9c88

[bungeman-skia, 2016-02-24 18:39:46]

Description was changed from

==========
Fully check basis vectors for extent degeneracy.

The test for 'nearly singular matrix' in SkScalerContext::computeMatrices
is actually a check to see if anything will draw. Unfortunately, the
current test only checks when the a skew causes nothing to draw. This
adds the check for when the scale causes nothing to draw.

BUG=skia:4998
==========

to

==========
Fully check basis vectors for extent degeneracy.

The test for 'nearly singular matrix' in SkScalerContext::computeMatrices
is actually a check to see if anything will draw. Unfortunately, the
current test only checks when the a skew causes nothing to draw. This
adds the check for when the scale causes nothing to draw.

BUG=skia:4998
GOLD_TRYBOT_URL=
https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&is...
==========

[bungeman-skia, 2016-02-24 18:40:05]

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

[commit-bot: I haz the power, 2016-02-24 18:40:07]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1735613002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1735613002/1

[commit-bot: I haz the power, 2016-02-24 19:07:04]

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

[commit-bot: I haz the power, 2016-02-24 19:07:05]

Dry run: This issue passed the CQ dry run.

[bungeman-skia, 2016-02-24 19:27:21]

bungeman@google.com changed reviewers:
+ mtklein@google.com, reed@google.com

[reed1, 2016-02-24 19:40:01]

reed@google.com changed reviewers:
+ jvanverth@google.com

[jvanverth1, 2016-02-25 19:00:33]

https://codereview.chromium.org/1735613002/diff/1/src/core/SkScalerContext.cpp
File src/core/SkScalerContext.cpp (right):

https://codereview.chromium.org/1735613002/diff/1/src/core/SkScalerContext.cp...
src/core/SkScalerContext.cpp:730: SkVector diag[4] = { { A.getScaleX()          
    ,                 A.getSkewY() },
I think you're multiplying these as row vectors, but it shouldn't matter for the
calculation. LGTM

[bungeman-skia, 2016-02-25 19:18:28]

The CQ bit was checked by bungeman@google.com

[commit-bot: I haz the power, 2016-02-25 19:18:38]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1735613002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1735613002/1

[commit-bot: I haz the power, 2016-02-25 19:34:14]

Description was changed from

==========
Fully check basis vectors for extent degeneracy.

The test for 'nearly singular matrix' in SkScalerContext::computeMatrices
is actually a check to see if anything will draw. Unfortunately, the
current test only checks when the a skew causes nothing to draw. This
adds the check for when the scale causes nothing to draw.

BUG=skia:4998
GOLD_TRYBOT_URL=
https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&is...
==========

to

==========
Fully check basis vectors for extent degeneracy.

The test for 'nearly singular matrix' in SkScalerContext::computeMatrices
is actually a check to see if anything will draw. Unfortunately, the
current test only checks when the a skew causes nothing to draw. This
adds the check for when the scale causes nothing to draw.

BUG=skia:4998
GOLD_TRYBOT_URL=
https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&is...

Committed:
https://skia.googlesource.com/skia/+/e37514d0b540a25471fe12ba6412dc4c8b9f9c88
==========

[commit-bot: I haz the power, 2016-02-25 19:34:15]

Committed patchset #1 (id:1) as
https://skia.googlesource.com/skia/+/e37514d0b540a25471fe12ba6412dc4c8b9f9c88